It seems hardly necessary to describe in detail the treatment demanded for the relief of the varied disturbances of the nervous system. The use of coca in the form of a good preparation of the wine or fluid extract in appropriate doses, to which may be added tincture of cannabis indica, exerts a favorable influence. The administration of cocaine by the mouth and hypodermically has in some instances seemed to me to be followed by favorable results. It is not, however, to be adopted as a routine practice, by reason of its occasional depressing effect and the possible danger of replacing the opium habit by a craving for cocaine. Lupulin, and in particular an ethereal extract of lupulin, exerts a favorable but not very powerful influence in tranquillizing the nervous system. With the view of controlling to some extent the insomnia, the hypodermic injections should, during the early part of the treatment, be so timed that the period of sleep or drowsiness which they produce should occur during the night. As soon as the number of injections is reduced to one daily, that one should be administered at the latest convenient hour before midnight. For twenty-four or forty-eight hours after the final discontinuance of morphine but little effect may be expected from ordinary doses of other sleep-inducing drugs. Chloral in single large doses (grs. xx to xxx), either alone or associated with a corresponding large dose (grs. xl to lx) of one of the bromides, administered on the second or third night after total suppression, is very often followed by prolonged, tranquil, and refreshing sleep. Caution must be observed, however, in administering chloral so long as the indications of feeble circulation persist. Paraldehyde, although less certain, is a less dangerous hypnotic under such circumstances. Massage, hot baths, and the cold pack are all useful adjuvants to the treatment. The sweating when copious and distressing is favorably influenced by sponging with hot alcohol.
The abject mental state of the patient calls for much firmness, gentleness, and tact on the part of the physician and attendants. Every effort should be made to inspire courage and hope. Neither the importance of the symptoms nor the intensity of the sufferings of the patient should be underrated; nevertheless, the ordeal is a limited one. In the majority of instances, to get rid of the opium means to get well, because opium, unlike alcohol, does not leave permanent structural lesions of any organ. The expectation of a radical cure must therefore be confidently presented to the patient as a consolation in his sufferings.
With the return of convalescence sexual power is restored and menstruation is re-established. Insomnia and muscular weakness usually persist into the convalescence for some weeks, and only gradually yield to careful regulation of the daily life of the patient, with abundant nutritious food, open-air exercise, and change of scene. The insomnia of this period constitutes a serious symptom, for the reason that it constantly subjects the patient to the temptation to return to the use of hypnotics. In the course of time, however, the normal physical and mental condition is regained, and the patient may be permitted to return to his former pursuits and associations.
The Treatment of the Chloral Habit.—That which has been said in the foregoing pages concerning the prophylaxis against the opium habit applies with equal force to chloral and other narcotics. The curative treatment of habitual addiction to chloral is attended neither by thedifficulties nor the dangers which are encountered in the management of the opium habit. The symptoms attending the discontinuance of chloral are less severe and less persistent; in fact, individuals accustomed to the taking of large doses of chloral not infrequently voluntarily discontinue its use for considerable periods of time. As a rule, the treatment may be carried out at home, the patient, however, being isolated and cared for by a watchful attendant. The drug should be stopped at once. For the first few days alcoholic stimulants should be freely given. Systematic feeding, pepsin, full doses of quinine, followed after a time by strychnia, and, as soon as the condition of the digestive system will permit of it, by iron, fulfil the general indications. Cod-liver oil and malt extracts may be given with advantage. Cardiac failure, collapse, and delirium tremens are to be treated in the same manner as similar complications occurring in the treatment of the opium habit. Vomiting is much less likely to occur, and when present is less persistent and less difficult of management. Diarrhœa does not usually prove troublesome, the bowels, on the contrary, being constipated. The latter condition yields to mild laxatives or to simple enemata. Hemorrhages from the various mucous tracts may be controlled by fluid extract of ergot, the hypodermic injection of solution of ergotin, minute doses of wine of ipecac, or fluid extract of hamamelis. The conjunctivitis which is occasionally present usually subsides spontaneously upon the discontinuance of chloral. It may be treated by instillations of a 2 per cent. solution of cocaine and mild borax lotions (grs. v to fluidounce j). The after-treatment must be carefully carried out. Relapses are less frequent than after the opium habit.
The Treatment of Habitual Addiction to Paraldehyde, Cannabis indica, Ether, Chloroform, etc. must be based upon the general principles indicated in the foregoing pages. Cases of the habitual abuse of these drugs are comparatively infrequent on the one hand, and on the other do not often present the serious and progressive symptoms produced by excesses in opium and chloral; hence they come but rarely under the care of the physician, except in those unhappy individuals in whom the propensity to vicious narcotism is such that any drug capable of producing excitement and oblivion is made the means of gratification, and all are used by turns as the opportunity occurs.
BYJAMES C. WILSON, M.D.
BYJAMES C. WILSON, M.D.
DEFINITION.—The term chronic lead-poisoning is used to designate the morbid phenomena induced by the gradual accumulation of lead in the organism.
SYNONYMS.—Plumbism, Saturnism, Morbus plumbeus, Molybdosis, Molybdonosus, Intoxication saturnine, Bleivergiftung.
CLASSIFICATION.—Chronic lead-poisoning manifests itself in serious disorders of nutrition which are widespread and implicate all the tissues of the body; but for the reason that its more striking and characteristic symptoms relate to the nervous system, it has been classed among disorders of that system as a toxic neurosis.
Acute poisoning by lead is an entirely different affection. It depends upon the power of the salts of lead to coagulate albumen. Its symptoms are those of acute corrosive gastritis; derangements of the nervous system are secondary. It does not fall within the scope of the present article.
HISTORY.—Chronic lead-poisoning must have existed from the infancy of the arts in which the metal is employed. It does not, however, appear to have been recognized until after the time of Hippocrates. Celsus was aware of the danger attending the administration of lead. Nicander, Dioscorides, Aretæus, and Paul of Ægina recognized lead colic and the paralysis resulting from its long-continued introduction into the stomach. Among Arabian physicians, Rhazes and Avicenna accurately describe the effects of the preparations of lead. No considerable addition to the knowledge of the subject was made until the seventeenth century. In 1616 was printed at Poitou the famous work of Citois,De novo et populari apud Pictones dolore Colico bilioso Diatriba. The epidemic colic described by this author was caused, although he little suspected it, by the common use of wine which had been treated by lead to remove its acidity. This practice, which is of very ancient date, and is described in the writings of Cato, Pliny, and Columella, was at one period very general in Europe, and had been forbidden by imperial ordinances as early as 1437.1It remained for Stockhausen, in a treatise published at Goslar in 1656, and entitledDe Lythargyrii Fumo, noxio, morbifico ejusque metallico frequentiori morbo vulgo dicto Hutten-Katze, to demonstrate that Poitou colic was produced by lead in particles inemanations, and for Wepfer in 1671 to first clearly point out the fact that the epidemic colic so often described was usually caused by lead in wine. During the eighteenth century the epidemic colic attracted much attention among medical men, and its etiology was made clear. Henkel called the affection founder's colic, and showed how it was produced in those engaged in casting lead; Huxham, in his work onFevers(1745), described the disease as it prevailed in Devonshire, and several English observers conclusively proved that the epidemics of colic frequently appearing in certain districts were caused by the presence of lead in cider, and that it was due to the action of the apple-juice upon lead used in the construction of the presses and implements employed in the manufacture of that popular beverage.
1Vide Tanquerel des Planches,Lead Diseases, translation by S. L. Dana, M.D., LL.D., Lowell, 1848.
During the current century the closer study of the etiological relations of disease has revealed many unsuspected sources of lead-poisoning in the arts, and of lead contamination, both accidental and intentional, in articles of food, drink, and luxury. Hence the literature of the subject has assumed very extensive proportions. The French physicians have devoted much attention to this subject. The great work of Tanquerel des Planches, to which reference has already been made, remains to this day the most complete and comprehensive authority. Quite recently valuable additions to existing knowledge have appeared in some of the Paris theses.2
2Vide Capelle,De l'Intoxication saturnine, Paris, 1883; Séguin, Ch.,De l'Albuminurie transitoire des Saturnins, Paris, 1883; Goudot,Étude sur la Goutte saturnine, Paris, 1883; Verdugo,Contribution à l'Étude de la Goutte saturnine, Paris, 1883; and Coutard,La Colique du Poitou considérée comme Intoxication saturnine, Paris, 1884.
ETIOLOGY.—A. Predisposing Influences.—Individuals exposed to lead and its compounds are not all equally prone to its effects. The degree of liability is to some extent dependent upon individual susceptibility, and to a much greater extent upon circumstances which are determined by the season, climate, age, sex, diet, and mode of life of different persons. It will be convenient to consider the predispositions which arise from occupation under the head of the Exciting Cause.
Variations in the degree of susceptibility to chronic lead-poisoning appear to be explicable in a majority of the cases solely upon the theory of idiosyncrasy. While a large proportion of the cases are in well-developed, strong, and previously healthy adults, individuals of feeble constitutions do not escape. Those occupations which involve the greatest exposure to the danger of contracting this affection at the same time demand the powers of a robust frame. Habitual recognition of these dangers, such as begets the habitual exercise of reasonable precautions against them, diminishes to some degree the liability of a few workmen.
Season.—Due allowance being made for the difference in the number of workmen employed in manufactures which involve exposure to lead, and especially in the making of white lead, at different seasons of the year, it has been found that attacks of lead colic and of lead palsy are more common in warm than in cold weather. Heat predisposes to the attack, either by favoring the dissemination of the lead compounds or by facilitating their absorption by various channels, especially by the skin, which is more freely exposed in summer, and at the same time more or less bathed in sweat in which the dust of lead salts may be dissolved.
Climate.—In the absence of definite statistics upon the subject, it appears probable that the dangers of chronic lead-poisoning would be greater in warm than in cold climates. The clinical features of the affection are alike in all parts of the globe.
Age.—The majority of individuals attacked are adults. Nevertheless, children employed in occupations involving exposure to lead are attacked with great frequency—so much so that it may be concluded that their liability is in fact greater than that of adults.
Sex exerts a decided influence, women being, under nearly similar circumstances, less frequently attacked than the men employed in the same factories—a fact to be explained only by their greater willingness to exercise the recognized precautions.
Diet does not constitute a predisposing influence. It is nevertheless probable that a deficient diet favors the development of the affection. Excesses in food, and especially excesses in drink, predispose to lead colic.
The mode of life is important. Those who lead sober, regular, and, above all, cleanly lives are less liable to the affection than the intemperate, irregular, and careless. Particularly are the dangers in factories increased by neglect of ventilation. Persons suffering from affections of the digestive tract are not, among lead-workers, more prone to lead colic than their comrades who are free from such diseases.
B. The Exciting Cause.—Metallic lead is probably inert, but, owing to the ease and rapidity with which it oxidizes and forms salts, lead in any form, if introduced into the body continuously for a length of time, produces characteristic toxic effects. The oxides, acetates, and carbonate of lead, being soluble in the gastric juice, act more surely.3But the sulphate, the least soluble of the lead compounds, may also have this effect (Gasserow).
3Naunyn,Ziemssen's Encyclopædia, vol. xvii.
The channels by which lead is introduced into the body are the alimentary canal, the respiratory tract, and the cutaneous surface. Hence the modes of introduction are of almost endless variety. The conveyance of lead into the stomach constitutes the most common as well as the most important means of access to the organism. This may be in the form of medicine, as the acetate, the unduly prolonged use of which, even in moderate doses, sometimes produces chronic poisoning. Articles of diet are not infrequently contaminated by lead derived from different sources, of which the most common is the lead glaze of earthenware vessels, which is soluble in acid fluids. According to Naunyn, beer drawn through lead pipes may cause chronic lead-poisoning, which has also been frequently ascribed to the use of shot in cleaning bottles used for wine and malt liquors. Drinking-water is occasionally contaminated with lead derived from pipes made of this metal and cisterns painted with lead colors. Pure water, freed from gases, does not act upon lead when the air is excluded. In the presence of air, however, an oxide of lead is formed which is partially soluble in water. If nitrates, nitrites, and chlorides, such as constitute ingredients of sewage, are also present, they form soluble compounds with lead and increase the proportion of lead salts soluble in the water. For this reason water contaminated by sewage is rendered decidedly more dangerous if carried in leaden pipes. On theother hand, the purer the water the greater the danger. Hence rain-water and pure spring-water cannot safely be stored in cisterns painted with lead colors nor conveyed in leaden pipes, nor can lead covers be used for cisterns, because of the condensation of the vapor of water, which drops back, holding lead salts in solution. The sulphates, phosphates, and carbonates usually found in river-waters form insoluble lead compounds, which, being deposited upon the interior of the pipes, act as protectives and prevent further chemical changes.
Still more common is the accidental conveyance of lead dust and lead compounds to the mouth in consequence of their adhering to the hands or settling from the atmosphere upon articles of food and drink, in the case of workmen engaged in the various arts in which lead is freely used. As a rule, to which the exceptions are rare, the more severe cases of chronic lead-poisoning occur only among workers in lead, as miners, those employed in white-lead factories, painters, typesetters, plumbers, and lapidaries.
Potters engaged in the glazing of common pottery and tiles, workmen in file-factories, workers on colored papers and in enamels, especially in glass enamels, brushmakers for the reason that the bristles are sometimes colored by lead preparations, and those engaged in sewing coarse goods because the thread is sometimes treated with a preparation of lead in order to add to its weight, are likewise liable to chronic lead-poisoning. The introduction of lead into the body through the respiratory tract is a subject of the greatest importance in the trades. Inadequate ventilation of working-rooms, living or sleeping in apartments connected with or contiguous to factories in which lead is largely used, and particularly in lead-factories, is attended with serious dangers, as is also the habit of eating food in such apartments or drinking water that has been standing in them. The possibility of lead-poisoning by way of the respiratory tract has been questioned. In view of existing knowledge as to the readiness with which carbon in minute states of subdivision finds its way into the connective lymph-channels of the lung, there can be no doubt that the habitual respiration of an atmosphere loaded with the dust of lead or its preparations in a minute state of subdivision may give rise to chronic lead-poisoning. At the same time, the experiments of Hassel4render it probable that less absorption takes place directly by means of the pulmonary mucous membrane than by way of the mucous membrane of the mouth and throat. It must be borne in mind that none of the preparations of lead are volatile. This affection is also occasionally observed in clowns and others upon the stage or elsewhere, who habitually use cosmetics containing lead. The use of cheap tinfoil, into the composition of which lead enters largely, as a wrapper for tobacco and snuff is said to occasionally produce chronic lead-poisoning. It is stated by Naunyn that mattresses filled with horse-hair died black by lead compounds have occasioned this affection. The same authority states that a proof-reader was poisoned by reading printed proof for many years. Chronic lead-poisoning is pre-eminently a disease of the industrial arts. The means of obviating or diminishing the dangers of those exposed by their occupation to the preparations of lead will be considered under the head of Prophylaxis.The quantity of lead absorbed is of less importance than is its continuous introduction. As stated in the definition, the phenomena of chronic lead-poisoning are those brought about by the gradual accumulation of lead in the system, the amount absorbed into the blood in any given cases being comparatively small, even where large quantities are ingested. Hence prolonged exposure to small amounts of lead is attended with greater danger than a comparatively brief exposure to larger quantities. It is stated that the members of the household of Louis Philippe at Claremont manifested the symptoms of chronic lead-poisoning after the lapse of seven months in consequence of drinking water which contained a mere trace of lead. On the other hand, several grains of acetate of lead may often be administered medicinally to patients for a week at a time without inducing the phenomena of this affection, although, in view of the idiosyncrasy of many individuals, the exhibition of lead preparations for prolonged periods is not advisable.
4The Inhalation Treatment of the Diseases of the Organs of Respiration, including Consumption, London, 1885.
According to Heubel,5the blood and internal organs contain but very small amounts of lead—.02 per cent. in the maximum. It is probable, therefore, that the more insoluble of the lead compounds may yield a sufficient amount of absorbable lead to produce the characteristic constitutional effects.
5Pathogenese und Symptome der Chronic Bleivergiftung, Berlin, 1871.
So long as the urine remains free from albumen, it serves for the elimination of a mere trace of lead. In albuminous urine the amount is larger. Lead is found in the bile and feces in small quantities.
SYMPTOMATOLOGY.—The general description of chronic lead-poisoning must include a great number of symptoms that do not always occur in regular order or sequence. According to the prominence of certain of these symptoms in particular cases the specific effects of lead may be grouped under the following five heads: (1) disturbances of nutrition; (2) the colic; (3) the arthralgia; (4) the paralysis; and (5) lead encephalopathy.
1. Disturbances of Nutrition—After the long-continued introduction of lead into the system the signs of impaired nutrition manifest themselves in almost all cases. The appearance of the patient is changed; he becomes thin, anæmic, and of a somewhat peculiar yellowish complexion. This hue of the skin, to which the term icterus saturninus has been applied, is not due to the deposition of bile-pigments. The wasting of the tissues of the body seems to implicate the muscular to a much greater extent than the adipose tissues. In the majority of cases a dark or bluish-black line is observed at the border of the gums. This line is more strongly marked in the upper than in the lower jaw. It is, as a rule, more plainly developed in persons of careless habits, whose teeth are the seat of deposits of tartar, but the teeth in such individuals are often discolored and appear to be elongated in consequence of the retraction of the edge of the gums. This bluish or violet-black gingival line is due to the deposit of particles of sulphide of lead in the substance of the gum, in consequence of the reaction between the sulphuretted hydrogen formed by the decomposition of particles of food and the lead particles present in the mouth. According to Tanquerel, this color may extend over the greater part of the gum or even to the mucous membrane of other portions of the mouth. If due care be exercised, there is little dangerof confounding the lead-line with the livid border of the gums frequently seen in people whose teeth are in bad condition. The occasional absence of this line in otherwise well-characterized cases of chronic lead-poisoning is to be noted. It does not occur when the teeth have been lost, and is slight if they are kept clean.
Patients complain of habitual dryness of the mouth and of an insipid, mildly astringent, sweetish, or faintly metallic taste; the tongue is coated, the breath fetid. There are nausea and occasional vomiting. Constipation is common. The patient is now liable to attacks of lead colic, joint trouble, and the specific palsy, or to cerebral disturbances of grave character. Of these affections, colic is the most frequent; the joint affection is next in order; the paralysis far less common, and the cerebral disturbances comparatively rare. Continued exposure results after a time in an intensification of the malnutrition, either with repeated attacks of colic or the other specific disturbances, or occasionally in their absence, although at length the positive lead dyscrasia is established, characterized by obstinate dyspepsia, constipation, and intensification of the curious earthy or yellowish color of the skin, which is succeeded by the pallor of profound anæmia. Loss of muscular power with transient œdema now shows itself. The patient becomes apathetic, irritable, and morose. As the condition of cachexia deepens muscular tremor occasionally shows itself. After a prolonged period of profound ill-health the patient succumbs to some complication, among the more frequent of which are tuberculosis, pneumonia, and chronic interstitial nephritis. Gout is a very common complication of chronic lead-poisoning.
2. Lead Colic; Colica saturnina; Colique de plomb; Bleikolik.—This affection is also known as painter's colic, Devonshire colic, colica pictonum, the last term being derived from Poitou. It occasionally develops abruptly without previous symptoms. In the majority of cases, however, the earlier disturbances of nutrition before pointed out precede the attacks, often by a period of weeks or months. An increased tendency to constipation with transient recurrent abdominal pains, occurring sometimes immediately after food, more frequently at irregular intervals, often characterizes the prodromic period. There is, moreover, an intensification of the other symptoms of chronic lead-poisoning. The appetite is decidedly impaired, so also are the powers of digestion; the foul condition of the mouth becomes more annoying, and the peculiar taste alluded to more persistent and more marked. Constipation occasionally alternates with diarrhœa. The colicky pains which constitute the attack are of variable intensity, but usually severe. They are of the nature of true colic. Pressure over the seat of pain almost invariably gives relief, particularly in severe attacks. During the remission pressure is grateful to the patient. The position of the pain varies. Its most common seat is in the region of the umbilicus. It may occupy the epigastric and hypochondriac regions or the lower part of the abdomen, extending from side to side above the level of the pubic bone. These colics are of some minutes' duration, recurring after short intervals, which are characterized by a certain amount of continuous cramp. Tenesmus is frequent. It may be accompanied by strangury or retention of urine, with pain in the course of the ureters, the spermatic cord, or in the penis. Shooting pains in the breast also occur. The abdomenis retracted, and scaphoid to such an extent in some instances that the prominence caused by the bodies of the vertebræ is apparent in the median line of the abdomen. It occasionally happens, however, that retraction does not occur, the belly, on the other hand, remaining prominent. As a rule, to which there are few exceptions, the bowels are constipated. This condition is often stubborn. In rare cases, however, the colic is accompanied by diarrhœa. Nausea is of common occurrence. Vomiting is sometimes violent and distressing, being ushered in by repeated attacks of retching. The vomited matters are usually discolored by bile, and icterus of slight degree usually occurs. The pulse is invariably diminished in frequency, sometimes as low as 40 or even 30, per minute. It is at the same time full and tense. The pulse-frequency is occasionally variable within comparatively brief periods of time. Respiration is increased in frequency during the attack. The urine is small in quantity and of high specific gravity, and frequently contains small amounts of albumen. It is sometimes entirely suppressed. Fever is absent, and the slight increase of temperature occasionally observed is attributable to the restlessness of the patient. The intellectual condition usually remains clear, but in violent cases it is characterized by excitement. The paroxysms of pain are more severe in the latter part of the day and during the night. The course of the attack is irregular. Relapses, which may occur in the course of some days or even weeks, are frequent. The duration of the attack does not, as a rule, exceed a week, but the illness is often protracted by repeated relapses, and in continued exposure to the cause the tendency to colic may become chronic. The termination of the attack is in most instances as abrupt as its onset, and with the cessation of the colic the associated symptoms, such as retraction of the abdomen, constipation, vomiting, and diminished frequency of the pulse, rapidly subside. Lead colic is not unfrequently associated with the other affections of chronic lead-poisoning. The prognosis is favorable, the mortality being about 2 per cent.
3. The Arthralgia; Arthralgia saturnina.—The tissues entering into the formation of the joints and the muscular masses contiguous to them are frequently the seat of intense paroxysmal pains, which appear more or less suddenly, either with or without prodromes, and run a course similar to that of lead colic, exhibiting violent exacerbations and occasional more or less complete remissions. These pains are accompanied by painful contractions of the muscles. They are somewhat relieved by pressure and friction and aggravated by exercise and exposure to cold. Swelling and redness over the affected joints, ligaments, and tendons are absent. These pains do not follow the course and distribution of the nerve-trunks, and lack the tender pressure-points of true neuralgias. They are more common in the lower extremities, the knee being especially apt to be affected. When they affect the upper extremity the elbow and shoulder suffer more frequently than the other joints. The flexor muscles are much more frequently attacked than the extensors. The muscles of the back, especially the great masses of long muscles in the lumbar region, whose function is to sustain the equilibrium of the body, are frequently implicated. The intercostal muscles and the muscles of the neck are also frequently affected. The small joints and the muscles of the hands and feet as a rule escape. The pain is tearing and burning incharacter, and very often severe. It is occasionally associated with tremor. The derangement of the alimentary canal, especially constipation, which is so characteristic of lead colic, is often absent. Fever does not occur.
A careful study of these cases establishes the fact that in a considerable proportion of them the morbid condition is myalgic. Whether it be due to simple muscular malnutrition or to some specific action of lead upon the muscle-substance is not determined. The analogy between these muscular pains and lead colic renders it probable that in a large majority of the cases the latter view is correct. These pains are frequently associated with the attack of lead colic; sometimes, however, they precede the colic, while at other times they follow it. After a series of remissions and exacerbations the pain often ceases as suddenly as it began. As in other lead affections, relapses are frequent. The prognosis is favorable.
The English physicians, and especially Garrod,6Todd,7and Bence Jones,8have insisted upon the frequency of gout in chronic lead-poisoning. Murchison,9Wilks,10and others regard this association as causative. This view has not found general acceptance in France. Lancereaux11in particular, after a comparative study of the lesions of the kidney and of the joints in saturnine cachexia and the corresponding lesion of gout, concludes that the gouty kidney and the kidney of lead-poisoning have the same appearance, and are simply varieties of interstitial nephritis, and that the articular and arterial lesions in both affections are identical. So-called saturnine gout differs in no respect, either in its clinical or anatomical characters, from ordinary gout. It would therefore appear superfluous to describe saturnine gout. At the same time, it must be insisted upon that chronic lead-poisoning exercises an important influence in the production of gout—a causal relation due to the fact that lead diminishes the excretion of uric acid.
6Medico-Chirurg. Transactions, 1854, vol. lvi.
7Clinical Lectures, London, 1856.
8Transactions of the Pathological Society, London, 1856.
9Lancet, 1868.
10British Medical Journal, 1875.
11“Nephritis et Arthrites saturnines: coincidence de ces Affections paralleles avec la Nephrite et l'Arthrite goutteuse,”Arch. gén. de méd., Decembre, 1881.
4. Lead Palsy; Lead Paralysis; Paralysie Saturnine; Bleilähmung.—This condition is fourth among the affections due to chronic lead-poisoning, both in frequency and in the order of succession. Nevertheless, like each of the others, it may be the first in the order of appearance after disturbances of nutrition which are in some rare cases of very slight degree. As a rule, however, the paralysis has been preceded by colic or by joint affection, or by both. Tanquerel12found that in 88 cases of lead palsy 25 had been preceded by an attack of colic, 15 by two attacks, 3 by ten attacks, 1 by fifteen attacks, and that in single cases as many as twenty, and even thirty, attacks of lead colic had occurred before the appearance of paralysis.
12Loc. cit.
The length of time over which habitual exposure to lead without the development of palsy may extend was found by the same observer to vary from eight days to ten, twenty, or even twenty-five years. One individual first suffered from paralysis after fifty-two years of exposure.
Without dwelling upon the sources of error in statistics of this kind,it must be conceded that they establish in a general way the extraordinary differences in the susceptibility of individuals. There are persons who every time they are attacked with colic, of whatever degree of severity, suffer also from paralysis. Others, on the contrary, suffer from repeated attacks of violent colic without the development of paralysis.
Lead palsy is an affection of adult life. Of 102 cases, 2 only occurred in individuals below twenty years of age.
Like the other specific lead affections except the encephalopathy, palsy is more common in the summer than at any other season.
Those who have once suffered are very liable to successive attacks. Tanquerel and Maréchal have observed many returns of paralysis, presenting the characters of the original attack, many years after the patient had withdrawn from exposure to lead.
Perverted sensations of the parts about to be affected, such as coldness, numbness, and hyperæsthenia, may precede the attack. Impairment of motor-power, manifested by feebleness, stiffness, or awkwardness and tremor, also appears in the prodromic period. This trembling consists in slight agitation of the muscles, rather than in well-marked rhythmical contractions. These precursors may indeed constitute the attack, which occasionally, and especially under treatment, terminates at this point. The prodromic symptoms are less severe during the day, while the patient is at work; at night they are aggravated. After some days they end in the characteristic paralysis. Colic is a common precursor. After the attack some stiffness of the muscles is experienced, which terminates by rapid loss of power or abruptly in actual palsy. Occasionally encephalopathy precedes the paralysis. It is rare that prodromes are wholly absent.
In the great majority of the cases the upper extremities and the extensor muscles are first attacked. If the paralysis be slight other muscles may escape. The characteristic form of lead paralysis consists in loss of power in the extensors of the hands and fingers, especially of the extensor communis, without implication of the supinator longus. The muscles affected are in the region of distribution of the musculo-spinal nerve. The deformity is known as wrist-drop. Next in order, the triceps and deltoid are most frequently attacked. The lower extremities commonly escape for a considerable time. When attacked, the extensor muscles of the feet and toes are the first to suffer.
Paralysis of the dorsal muscles occurs in rare instances. It gives rise to a peculiar stooping, uncertain, and tottering gait. Paralysis of the intercostal and laryngeal muscles was observed by Tanquerel. Paralysis of the muscles of the face or of those of the eye has never been observed in consequence of lead-poisoning. The loss of power never corresponds strictly to the distribution of the branches of a single nerve-track.
The paralysis, as a rule, affects both sides, and frequently the corresponding muscles of the two extremities. Sometimes, however, the affected muscles of the two sides are not the same, and it occasionally happens that the affection is limited to one side. In very rare cases, the arm and leg on the same side being paralyzed, the affection resembles hemiplegia.
Local paralysis may be limited to the extensor muscle of a single fingeror may involve all the muscles of a limb. There may be slight impairment of power in the flexor muscles. The enfeeblement of certain flexor muscles, especially of those of the fingers, may, Naunyn suggests, be only apparent, the position of the hands being in pure extensor paralysis unfavorable to the exercise of the flexors and limiting their function.
Sensation is not, as a rule, affected in lead paralysis. Pains in the paralyzed muscles, in neighboring muscular masses, and in the structures about the joints often precede the attack of paralysis. Anæsthesia of the skin is rare. When present, it is usually of slight degree, and corresponds to the region of the paralysis. Deep anæsthesia has also been observed.
Atrophy of the paralyzed muscles is constant and rapid. It frequently reaches a high degree, causing characteristic deformities, which are rendered more marked by the fact that the adjacent non-paralyzed muscles preserve to a great extent their original state of nutrition. As the neuro-muscular lesion progresses other deformities arise, in consequence of derangements of the balance of force between opposing muscles and from other causes. Among these deformities are partial or complete dislocations of the more movable joints, as the shoulder and phalanges, with the formation of tumors, which, when they occupy the dorsum of the hand, might be carelessly mistaken for the nodosities of gout. It is to be noted that the latter are occasionally present as complications.
There is rapid diminution, and finally complete loss, of the reaction to the faradic current. With the galvanic current the reaction of degeneration is usually well marked. The reaction of degeneration may be demonstrated in the extensors of the limbs in lead-poisoning before wrist-drop has occurred.
The course of lead palsy is very variable. In a few cases it is progressive. When local emaciation or atrophy arrives at the last degree of marasmus, the skin seems glued to the bones, to such an extent are the paralyzed parts wasted; the muscles especially are so thinned that the contour of the bones is easily distinguished. If the paralysis attack the whole of the limb, then this organ, abandoned to its own weight, stretches the ligaments and permits the head of the bone to leave its cavity. In other rare instances the paralysis remains stationary for long periods of time, only to grow worse after each new attack of lead disease. Much more frequently lead paralysis disappears spontaneously or under treatment in the course of some days or weeks. The convalescence is gradual, and usually rapid, when the gravity of the lesion is considered; occasionally it is complete in the lapse of a few days.
The prognosis depends upon the degree of lead cachexia present, the possibility of withdrawing the patient from the exposure, and finally upon the degree and extent of the paralysis and of the atrophy. It is rendered unfavorable by the necessity of the prolonged exposure of the patient to lead, by a high degree of disturbance of the general nutrition of the patient; and by the fact of his having presented for a considerable period the evidences of lead disease, with occasional attacks of colic or arthralgia; by the complete loss of power and electrical reactions in the affected muscles; and, finally, by absolute wasting of the muscular masses. The prognosis is less favorable in relapses than in the primary attack.
Progressive muscular atrophy has been frequently observed in patients suffering from lead disease (Naunyn).
5. The Encephalopathy; Encephalopathia Saturnina.—This term was suggested by Tanquerel to designate collectively the various morbid cerebral phenomena produced by chronic lead-poisoning. It embraces, therefore, those affections due to the action of lead upon the central nervous system, and occasionally described as lead insanity, delirium, convulsions, epilepsy, coma, etc. It is, of all the disorders produced by lead, the most rare. Tanquerel met with seventy cases only. It occurs only in those individuals who are exposed to large quantities of lead, and in such a manner as to favor the absorption of the metal and its compounds by the digestive and respiratory tract. Hence house-painters and the workers in lead-factories supply the greater number of cases. The time of exposure elapsing before the manifestations of the special morbid action of the poison upon the nervous system show themselves varies from a few days to many years. In a large proportion of the cases the time has been less than one year.
Women are much less liable than men—a fact clearly due to the nature of their occupations even when involving exposure to lead.
The majority of the cases have occurred between the ages of twenty and fifty. Alcoholic habits, insufficient and unwholesome diet, privations, exposure, and an irregular life especially predispose those working in lead to the affection. Lead encephalopathy has developed with nearly equal frequency in warm and in cold weather. Relapses are frequent.
Among the prodromes are headache, vertigo, agitated and interrupted sleep marred by distressing dreams, and troublesome insomnia; derangements of the special senses, dimness of vision, alterations of the pupils, tinnitus aurium; dysphagia and a sense of constriction of the pharynx have also preceded the attack of cerebral disorder. It is usually preceded likewise, and often by a considerable lapse of time, by the other lead affections above described—namely, colic, arthralgia, and palsy. Psychical derangements—stupor, apathy, or excitement—also precede the attack. In a small number of cases lead encephalopathy has occurred abruptly without prodromes.
The symptomatology is exceedingly variable and irregular. Three forms, the delirious, the comatose, and the convulsive, have been described. These conditions may succeed each other in the same attack. The delirium is variable in kind. It is apt to be at first tranquil; after some time it becomes paroxysmal and furious. It is broken by intervals of somnolence. At length true sleep supervenes, and the patient awakes restored almost completely to his reason.
Coma may develop suddenly, even instantaneously. In a very few cases the comatose form has developed itself alone during the course of chronic lead-poisoning. As a rule, however, it is preceded by delirium or convulsions.
The convulsive form is the most common. The convulsions may be partial, involving the face or the one side of it, a single limb, or one side of the body. They may be general, without loss of consciousness. These incomplete attacks are apt to be followed, after a period of dulness or unconsciousness, by acute eclampsia. Epileptiform attacks may now follow each other in rapid succession, ending in more orless profound coma. The attacks are sometimes separated by intervals of uneasiness, restlessness, or delirium. These attacks continue several days. If they are very violent and frequent death may rapidly supervene. In favorable cases consciousness is gradually restored, or the patient may awaken suddenly from his drowsiness after some hours or a day.
These attacks are not preceded by an aura.
Amaurosis is among the more important of the symptoms produced by the action of lead upon the nervous system. It is usually accompanied by dilatation of the pupils. The amaurosis gradually disappears as the other symptoms subside, and with the improvement in sight the pupils contract. Recovery is frequently complete. Occasionally vision does not return with the improved general condition. Norris13saw, in two cases of lead-poisoning due to the use of white lead as a cosmetic, marked choking of the discs in connection with severe cerebral symptoms. The terminal condition, when recovery does not take place, is that of nerve-atrophy.
13See thisSystem of Medicine, Vol. IV.
Albuminuria is common in this as in other lead affections. It may be of moderate amount and due to the rapid breaking-down of the blood-corpuscles which marks the exacerbation of the general condition. Albuminuria may be a direct consequence of the eclampsia. Finally, it may be due to coexisting nephritis.
The prognosis is in a high degree unfavorable.
MORBIDANATOMY ANDPATHOLOGY.—There are no well-characterized anatomical lesions in chronic lead-poisoning. Lead has been found in almost every organ and tissue in the body. It exists in combination with the albumen of the tissues. The changes in the nervous system that have thus far been described are neither constant nor characteristic. The same is true of the lesions of the intestines. The paralyzed muscles are found to have undergone atrophy, with loss of the striæ and increase of connective tissue. The nerve-trunks are also the seat of atrophic degeneration.
The mode of action of lead is not yet determined. The view of Henle, that lead acts chiefly upon the unstriped muscular fibre, was at one time generally accepted, and served to explain many of the characteristic phenomena of the disease. On the other hand, there is much in the clinical history to support the opinion of Heubel, that its primary action is upon the nervous system. Whether the peripheral degeneration by which the paralysis is to be explained is primary or secondary to central degeneration in the anterior cornua of the gray matter of the spinal cord, is yet in dispute. Some of the forms of encephalopathy are doubtless due to the nephritis which is found in many cases of chronic lead disease, and are, in fact, symptoms of uræmia. In the great majority of the cases this is not the case. The morbid condition must be explained by the direct toxic action of lead upon the central nervous system. No theory adequate to account for all the cerebral manifestations has yet been suggested. Naunyn has pointed out the resemblance between the nervous and psychical derangements in lead encephalopathy and those which characterize chronic alcoholism, and suggests that lead, like alcohol, produces these effects not as a direct poison, but indirectly in consequence of abnormal nutrition of the whole system, brought aboutby the continued circulation of a foreign poisonous material in the blood.
Chronic Lead-Poisoning in Animals.—Animals exposed to lead under conditions favorable to the development of the lead affections in man suffer in like manner. Instances of this kind are of frequent occurrence in and about large lead-factories. The drinking of water containing lead also gives rise to these affections in animals. Horses, dogs, cats, and fowls have frequently suffered from lead colic. Horses used in lead-factories suffer from a form of laryngeal obstruction due to lead paralysis of the muscles of the larynx. Relief has followed tracheotomy and the introduction of a canula, and removal to an atmosphere free from lead has resulted in recovery. Cats who spend some time in red-lead workshops frequently are paralyzed. Even the rats in lead-factories become paralytic (Tanquerel).
DIAGNOSIS.—The diagnosis of the affections due to chronic lead-poisoning is, as a rule, unattended with difficulty. The malnutrition, anæmia, poor digestion, foul mouth, stubborn constipation, and the gingival line, considered in connection with the history of prolonged or habitual exposure to lead, would warrant the assumption that the relation between this poison and the symptoms is a causal one. When there is added colic, arthropathies, and paralysis, or the cerebral states having the characters above described, the assumption becomes a certainty. The absence of any one of the ordinary phenomena, such as the blue line or constipation, would still leave the clinical picture sufficiently full to justify the diagnosis. The reaction of degeneration, which is usually marked in saturnine wrist-drop, with the escape of the supinators, distinguishes it from pressure paralysis of the musculo-spiral.
TREATMENT.—A. Prophylaxis.—Free ventilation and scrupulous cleanliness constitute, in general terms, the most efficient safeguards for those whose occupations involve prolonged exposure to lead. Workmen employed in lead-factories and those otherwise exposed to lead should be compelled to wash their hands and change their outer clothing before eating; they should also bathe regularly every day on leaving work; under no circumstances should they be suffered to eat or sleep in or near the workshops. As all kinds of work in the manufacturing of lead preparations are not attended with equal risk, the workers should from time to time be transferred from one department to another or from in-door to out-door work. In order to prevent the constant rising of dust, the floors are to be kept constantly sprinkled or covered with moist sawdust. It is unnecessary to go into further details in regard to the hygiene of the subject. It is probable that towels and sponges worn over the mouth, or other forms of respirators, because of the inconvenience which they occasion and the false sense of security which attends their use, are of less value than has been generally supposed.
It appears scarcely needful to here insist upon the avoidance of cosmetics and hair-dyes containing lead, or upon the exercise of reasonable prudence in the matter of the manufacture, sale, and use of articles of food or drink which are liable either by accident or design to become adulterated with lead compounds.
The use of sulphuric-acid lemonade is a measure of prophylaxis of less real value than was at one time supposed, seeing that the sulphate of leadis in itself capable of producing the disease. Occasional doses of magnesia sulphate are of use where a tendency to constipation exists. Workmen who begins to show signs of chronic lead-poisoning should without delay abandon their work and seek some occupation free from its peculiar dangers.
The precautions against the use of water contaminated with lead have been pointed out under the heading Etiology.
B. Curative Treatment.—When the disease shows itself, no matter in what form, the primary indication is the discontinuance of exposure to lead. Chronic cases of malnutrition, constipation, functional nervous disorder, will occasionally be found upon careful search to depend upon long exposure to lead in some unsuspected way. The cause being removed, such cases often promptly recover.
Measures aimed first at the separation of the lead from the tissues, and then at its elimination from the body, constitute a rational treatment. Sulphur baths and the internal administration of sulphur may be employed with a view of converting the lead eliminated by the skin and mucous membranes into an insoluble sulphide, and thus preventing its resorption. Repeated laxative doses of castor oil will remove unabsorbed lead from the intestinal canal. The plan of treatment at present in general favor consists in the combined use of potassium iodide and magnesium sulphate. From five to twenty grains of the iodide are to be given in not less than six or eight fluidounces of water three times daily, the stomach being empty: two hours after each dose one or two drachms of the magnesium sulphate are to be taken; after this dose an ordinary meal.
This treatment is designed to dissolve the lead deposited in the tissues, and cause its elimination by the mucus of the alimentary canal in part, and to a slight extent also by the urine. The magnesium sulphate tends to remove such lead as finds its way into the alimentary canal thence with all possible rapidity. These measures, together with the removal of the patient from further exposure, exert of themselves a favorable influence upon the malnutrition and anæmia. Quinine, strychnine, iron, cod-liver oil may be advantageously administered as the toxic effects of the lead pass away.
The colic demands the administration of opium or its derivatives to relieve the pain, which is commonly excruciating. For this purpose the hypodermic injection of morphia is our most efficient remedy. Alum in doses of twenty to thirty grains every four or six hours is useful in lead colic.
For the relief of the local paralytic affections local as well as general treatment is necessary. Massage is of great use, especially when combined with passive movements. Galvanism, one large electrode being applied to the cervical vertebræ, the other to the extensor surface of the affected limbs, is followed by excellent results. Labile currents of fifteen or twenty cells should be thus applied, the poles being changed several times at each sitting. As the nutrition of the muscles improves faradic currents may be occasionally substituted. Persevering treatment is necessary to obtain the best results.
For the present relief of the arthralgia gentle frictions with or without anodyne liniments must be employed. The hypodermic use of morphinemay become necessary in cases in which the pain is urgent. It is, however, here as elsewhere, to be if possible avoided. The tendency to recurrent joint-pains rapidly disappears as the poison is eliminated from the organism.
For the relief of the severe cerebral symptoms which are described under the term Encephalopathy special treatment is of little avail. All observers agree in recommending an expectant plan. The measures of treatment directed against the general condition, as above described, must be steadily continued. The influence of chronic lead-poisoning upon pregnancy is very deleterious. Constantine Paul14and others have shown that the early death of the fœtus very constantly occurs. The prompt removal of women who have become pregnant, from all exposure to lead, and energetic medicinal treatment, are needed to obviate the danger of abortion.
14Arch. gén. de Méd., vol. xv., 1860.