PURPURA.
BY I. E. ATKINSON, M.D.
It has been customary with authors to describe under the general heading Purpura a number of affections presenting as a common symptom the extravasation of blood into the tissues, more especially of the skin and mucous membranes, quite irrespective of etiological or pathological considerations. Thus, the tiny ecchymoses caused by the bites of fleas have been denominated purpura pulicosa; the larger bruises resulting from external violence, purpura traumatica; the extravasations occurring in the course of scurvy, purpura scorbutica; those encountered in malignant small-pox, purpura variolosa; and so on. These affections, differing widely in nature, possess as a common symptom the escape of blood from the vessels into the tissues. It is evident, therefore, that in the sense often employed the term purpura is used to describe a symptom or symptoms common to a variety of non-related maladies.
If there be a peculiar morbid process having for its constant and characteristic symptom the spontaneous escape of the blood from the blood-vessels, it is plain that interstitial hemorrhage from external violence or from the action of a definite poison circulating in the blood and disorganizing it and its containing vessels, as in phosphorus-poisoning, or from the influence of certain zymotic diseases, should not be designated by the title properly belonging to a substantive malady. The question, therefore, is: Are there groups of symptoms indicating morbid action of definite character, but of varying intensity, to which the name purpura may with propriety be applied?
In the present light of pathological science it is impossible to answer this question in the affirmative without considerable qualification. It must be confessed that we do not possess a knowledge of any definite chain of morbid processes constituting a distinct disease that may be designated as purpura. And yet we are able to recognize a set of symptoms varying greatly in intensity, from the most trivial petechial eruption to profuse and fatal hemorrhages, accompanied by a train of manifestations which we are unable to connect with any of the causes already spoken of, and which, indeed, depend upon no fixed exciting cause with which we are acquainted. It may be eventually proven that purpura, even as we understand it, is merely a set of phenomena due to widely-differing influences acting upon the blood and blood-vessels, and that the term will disappear from our nomenclature as indicating a disease, but will be preserved as denoting a symptom. For the present, purpura is understood to be a group of symptoms characterized by the effusion of blood into the tissues of the body, or upon its free surfaces, or into its serous cavities, which seem to arise spontaneously, and for which we are unable to assign a definite cause. With this view of the nature of purpura it becomes necessary to exclude from present consideration blood-extravasations from internal or external violence, the action of the specific principles of contagious or infectious fevers, the dyscrasia of scurvy, the influence of poisonous substances, and, in a word, any of those affections of which the escape of blood from the vessels constitutes an epi-phenomenon.
Purpura may be conveniently considered as presenting three varieties: 1, purpura simplex; 2, purpura hæmorrhagica; 3, purpura rheumatica.
These three forms of the disease are not distinguished by sharply-outlined differences, but merge the one into the other, now one, now another set of symptoms predominating. To these may be added, likewise for convenience, three sub-varieties—purpura urticans, purpura papulosa, and purpura nervosa. The difference between these forms of purpura should not be considered as of more than clinical import. Whatever variations present themselves may with probable propriety be ascribed to complicating influences.
PURPURA SIMPLEX.—This is the mildest form of purpura, and may in many cases readily escape observation. It may begin abruptly, in the midst of health, without the slightest subjective symptom, or the extravasations may be preceded for several days by some discomfort, aching of limbs, sluggishness, anorexia, even a small amount of fever. The eruption usually appears first upon the lower extremities, preferably the flexor surfaces of the thighs (Duhring), but frequently upon the legs. It extends from these points to the upper extremities and trunk, usually sparing the face. The lesions vary in size from that of a pin-head to that of a fingernail (petechiæ), or they may be linear (vibices). They remain discrete, and do not increase in size throughout their course. Each spot of hemorrhage will endure for from one to two weeks. At first the lesions are of a livid red color, and declare their extra-vascular nature by remaining unaltered when subjected to pressure. The color of these spots changes, as in ordinary ecchymosis, in consequence of the metamorphoses of the hæmatin preparatory to its final absorption, from crimson to purple, to blue, to green, to yellow, and finally fades away. When recent, the spots appear sharply outlined, with sometimes a faint encircling zone of hyperæmia, but as they become older their margins grow indistinct. While the early lesions slowly disappear, others continue to develop, and the affection may thus be protracted for weeks. At times the petechiæ appear in crops, recurring every few days, the patient at one time apparently nearly well, at another time worse than ever. Finally, the symptoms definitely disappear, to return no more, or they pass into those of other forms of purpura. During the course of purpura simplex the blood-vessels of the skin alone are affected, the deeper tissues and mucous membranes probably remaining unchanged.
Throughout the attack the general health may—usually does—remain good. As an occasional symptom there will be observed a few vesicles or blebs, containing blood, upon the skin. The extent of the general eruption may vary from a few scattered petechiæ to a copious and startling number of purpuric spots. The maintenance of the upright position tends to perpetuate the evolution of the lesions.
In elderly persons purpura simplex is sometimes observed, and has been described by many writers as purpura senilis. Hillier, following Bateman, describes it as occurring in old women "upon the outside of the forearms in successive dark, purple blotches of an irregular form and various magnitude."1 Aged men as well as women are liable to the affection, which may quite as well appear upon the lower extremities of either sex. It is altogether likely, however, that in such cases degenerations of the vascular walls alone may cause the extravasations.
1 Reynolds's System of Medicine, vol. i. p. 792.
PURPURA HÆMORRHAGICA (MORBUS MACULOSUS WERLHOFII).—In this form of purpura there are added to the symptoms of purpura simplex hemorrhages into and from the various mucous tracts, the nasal, faucial, pharyngeal, gastric, intestinal, renal, uterine, rarely the pulmonary mucous membranes, and exceptionally into the various serous membranes and cavities. It may begin abruptly, in the midst of apparently vigorous health, or after premonitory symptoms extending over several days, vague sensations of discomfort—headache, pains, anorexia, indisposition to exertion, and the like—or it may occur as a transition from other forms of purpura. Usually there is no fever.
The hemorrhagic spots upon the skin appear much as in purpura simplex, though the lesions are larger, acquiring the size of coins or even of the palm of the hand. Spots soon appear upon the visible mucous membranes, and free hemorrhages occur; indeed, the latter may be the first symptom observed. Epistaxis is of most common occurrence, but bleeding from the mouth, stomach, and intestines almost as frequently results. The gums are almost constantly affected, and upon inspection these may be found covered with blackish scabs, upon removal of which the mucous membrane will be found pale and not swollen—an important point in diagnosticating this affection from scurvy. Vesicles and blebs filled with blood form both on the skin and mucous membranes. They quickly rupture and discharge their contents. Bleeding from the stomach and intestines is revealed—in the former case by the vomiting of a brownish material resembling coffee-grounds; in the latter case by the passage of black, tar-like evacuations. Pulmonary hemorrhage is to be distinguished from hæmatemesis by the frothy and arterial character of the blood. Hæmaturia may proceed from any part of the urinary tract. Bleeding from several parts may occur at the same time, and may be very copious.
In the mucous membranes extravasations of greater or less extent may occur, as in the derma. Into the serous membranes they may take place with or without effusion into serous cavities. It is only, however, in cases that will almost certainly end fatally that the effusions into these cavities are encountered. Hemorrhages into the substance of the lungs, into the brain and other viscera, as well as into the tissues generally, are occasionally observed.
At the outset of these bleedings the general health of the patient may appear unimpaired, and if they be few in number and moderate in extent but slight evidences of debility may be shown throughout the attack; but it is often the case that the loss of blood is excessive and long continued, and symptoms of profound anæmia supervene. The patient becomes greatly exhausted; intense pallor is developed, shortly followed by general oedema. Attacks of syncope appear, and in fatal cases—which are not common—death results from asthenia. This result may occur after a few days from the profuseness of the hemorrhage; usually, however, only after several weeks. Throughout the attack the cutaneous lesions continue to develop, either irregularly or in successive outbreaks, scattered over the general surface, involving the face less frequently than other parts. These spots undergo the color-changes peculiar to extravasated blood, and may be seen in all the stages of involution in the same patient. Fever, usually absent throughout the attack, may appear at the height of the affection, but does not run high. Local inflammations are exceedingly rare. In favorable cases recovery follows the gradual mitigation and disappearance of the symptoms, but relapses frequently occur, and convalescence may be retarded for months.
PURPURA RHEUMATICA (PELIOSIS RHEUMATICA).—Schoenlein in 1829 described as peliosis rheumatica an affection in which the symptoms of purpura simplex were associated with pain and often with effusion into the joints, especially those of the knee and ankle. He considered it as an independent malady. This opinion has been shared by Fuchs, Hebra, Kaposi, Neumann, and many others. Kaposi2 regards it as related to erythema nodosum, with which affection, indeed, it possesses some features in common. It probably, however, constitutes a complication of ordinary purpura. That it is not primarily rheumatic is shown by the almost invariable absence of many of the symptoms characteristic of rheumatism; that it cannot be an independent affection appears from its intimate relations with other forms of purpura.
2 Hautkrankheiten, 1880, p. 277.
Purpura rheumatica commonly begins with malaise, anorexia, debility, sometimes with mild fever. The patient is soon attacked with pains, of a more or less acute character, in the joints, especially the knees and ankles. There may be some effusion into the joint and cutaneous oedema. After a few days the nature of the complaint will be revealed by an eruption of petechiæ, first near the painful joints, but soon extending, involving in many cases even the head and trunk. The eruption may be at first slightly elevated and surrounded by a fine halo of hyperæmic injection.
The pains usually subside upon the appearance of the eruption, and the malady may be completed after a single outbreak. More commonly new joint-pains are experienced, fresh crops of petechiæ appear, and the trouble may be prolonged for weeks, even months, the patient meanwhile suffering not very greatly in general health. The lesions may be cutaneous only; rarely bleeding from mucous surfaces will occur (Scheby-Buch). Albuminuria may be present (Kaposi). An annual type is said by Kaposi, Neumann, and others to be sometimes observed, the spring and autumn being the usual seasons for the outbreaks. This is supposed to indicate a relationship with erythema nodosum and multiforme. Cardiac murmurs have been detected in the course of purpura rheumatica,3 but these were probably anæmic or antedated the purpuric symptoms. Purpura rheumatica never seems to result in endo- or pericarditis.
3 Kinnicutt, Archives of Dermatology, i. p. 193; Mollière, Ann. de Dermatol., v. p. 44.
SUB-VARIETIES.—Henoch4 and Couty5 have described a form of purpura mostly observed in children, in whom rheumatoid pains occur along with colic and vomiting of greenish or bilious matter, tenesmus, and sometimes with loss of blood from the bowels. The disease may be protracted throughout months by relapses. Cutaneous oedema frequently occurs. Couty regards it as a form whose peculiarities justify its assignment to a position of its own. The cause of the associated train of symptoms is supposed (Couty) to reside in the sympathetic system, and the name purpura nervosa is proposed for it. So many features of ordinary purpura are manifested in these cases that it seems better to consider them as examples of ordinary purpura complicated with gastro-intestinal derangement. It has been suggested that the nausea, vomiting, and abdominal pains may result from extravasation of blood into the peritoneal tissue.6
4 Berl. Klin. Wochenschr., 51, 1874.
5 Gaz. Hebd., 36 et seq., 1876.
6 Immermann, Ziemssen's Cyclopæd., vol. xvii. p. 265.
In the course of purpura there is frequently observed, more especially in purpura simplex, a wheal-like arrangement of the eruption—such, indeed, as occurs in urticaria. The term purpura urticans has been given to this sub-variety, which may or may not be accompanied by itching. Scheby-Buch has suggested that the urticaria may, with more propriety, be attributed to the gastric disturbances that so often accompany the forms of purpura presenting it.7 The wheals are usually seen upon the lower extremities, but may appear elsewhere. A considerable degree of oedema may be present, particularly in lax tissue, such as that of the scrotum, eyelids, etc.
7 Deutsche Arch. f. Klin. Med., B. xiv. p. 490.
Purpura papulosa (lichen lividus, Willan) is a form of purpura where, in the midst of ecchymoses, livid papules appear. These probably depend upon a large amount of hemorrhage occurring within a limited space, most often surrounding the orifices of hair-follicles, because these are supplied with a capillary network that comes directly from the deeper layer.8 They are formed most abundantly on the legs of scrofulous, cachectic persons who have purpura. Care must be taken to distinguish this form of purpura from erythema multiforme and erythema nodosum, where blood is usually extravasated secondarily into the tissues. Those cases only where the purpura is primary should be recognized as purpura papulosa.
8 Hebra, Skin Diseases, New Syd. Soc. Transact., ii. p. 425.
The purpuric effusion appears to act as an irritant upon the tissues, and to excite inflammation. Gangrene of the mucous coat of the intestines has resulted from extensive hemorrhagic extravasations, and from a similar cause cutaneous gangrene has been known. These complications, however, are rare.
ETIOLOGY.—The immediate causes of purpura are quite unknown. Both sexes and persons of every age are affected by it. While it is most often seen in debilitated subjects, those in vigorous health possess no immunity. It has often been observed during convalescence from other maladies. It cannot be said that those who are miserably clothed, fed, and lodged are especially predisposed to attacks of purpura. Between purpura and hæmophilia, etiologically, there are many points of difference. Purpura is not hereditary, nor is there a purpuric diathesis in the strict sense of the term. Some persons, indeed, seem to possess a predisposition to the disease, and some authors claim for purpura rheumatica a distinct annual type. This, however, is not at all certain.
Recently it has been claimed that purpura hæmorrhagica depends upon the presence of a minute organism in the blood. Petrone9 injected blood drawn from patients with this disease under the skin of rabbits, producing widely-distributed hemorrhages. In the blood of these individuals and of the injected rabbits micrococci and bacilli were detected. Watson Cheyne10 also describes a plugging of the capillaries with bacilli. These were 1/7700 of an inch in length and 1/20000 of an inch in diameter, and were arranged in colonies. In another case there were found micrococci arranged in chains. These swarmed in the capillaries and some larger vessels, and sometimes completely blocked them. Although an origin in infection has thus been claimed for purpura hæmorrhagica, the fact that more than one variety of micro-organism was observed cannot fail to excite suspicion of, possibly, erroneous observation.
9 Lo Sperimentale, 51, 1883.
10 Lancet, i., 1884, 344.
PATHOLOGY.—In the foregoing description those extravasations of blood due to simple mechanical violence, as from flea-bite, and sudden increase of blood-pressure, as in the effort of coughing in whooping cough, also from the deleterious influence exerted upon the blood-vessels and blood by certain drugs, the specific fevers, Bright's disease, and the like, have been excluded. Only those have been considered where the effusion of blood seemed to occur spontaneously, and the symptoms to result from some peculiar but not understood morbid process. The hemorrhage is but a symptom; the process by which it is brought about depends upon some change in the blood or blood-vessels. We do not know what these subtle changes are. The blood of purpuric patients has been carefully examined, but, with the exception above mentioned, no definite changes have been discovered. Immermann11 found during the first stage of the disease the blood-corpuscles perfectly normal in appearance, the white corpuscles subsequently slightly exceeding the red in number—a simple result of copious hemorrhage. No stated chemical changes in the blood are known in purpura, nor is it known how the blood escapes from the vessels. It undoubtedly escapes through alterations in the vascular wall, but it is also true that red blood-corpuscles, as well as the pale ones, may find their way in considerable numbers through the unruptured wall of the vessels, per diapedesin, as was first suggested by Velpeau, but definitely determined by Stricker. The causes of this migration are obscure. Immermann12 asserts that a fatty degeneration of the vascular tissues and of the muscles takes place. This, however, is manifestly a result of the loss of blood, and not its cause. Dr. Wilson Fox13 found extensive albuminoid disease of the muscles and capillaries of the skin; but the albuminoid degeneration involved several organs of a patient with syphilis, and the purpura was certainly secondary to the morbid conditions. Rigal and Cornil14 think that the hemorrhages are a result either of sympathetic irritation or of diminished action of the vaso-motor centre. It is indeed altogether likely that the cause will ultimately be found to reside in the vaso-motor system.
11 Ziemssen's Cyclop., xvii. p. 258.
12 Loc. cit.
13 Brit. and Foreign Med.-Chir. Review, Oct., 1865.
14 L'Union Méd., 5, 6, 7, 1880.
DIAGNOSIS.—The affection bearing the closest resemblance to spontaneous purpura is scurvy; indeed, its supposed relationship to this disease has given purpura one of its synonyms, land scurvy. The two affections, however, are probably without the slightest relationship. They possess in common the hemorrhagic symptoms, both in the tissues and from free surfaces, but the resemblance does not extend much beyond this. Scurvy depends upon deprivation of fresh vegetable food and the use of unsuitable and insufficient food generally, and upon bad hygienic surroundings. Purpura may—frequently does—appear in broken-down constitutions, but it equally attacks the strong and vigorous, while the character of food exerts no special influence on its production. Scurvy only follows long-continued privations and as a culmination of a train of distressing symptoms. Purpura appears in the midst of health, or after brief premonition, or during convalescence from totally unrelated diseases. In scurvy there is a decided tendency toward ulceration, which is absent in purpura. In scurvy the mouth and gums inflame and ulcerate, the latter becoming swollen, spongy, and of a bluish-red color. In purpura, ulceration of the buccal mucous membrane does not occur, and the gums are pale and intact. The curative influence of fresh vegetables, lime-juice, etc. in the treatment of scurvy is not observed in purpura. It has been claimed that purpura is but a mild degree of scurvy: this cannot be so, for we may have a mild scurvy or a severe, even fatal, purpura.
The hemorrhagic diathesis, or hæmophilia, presents points of analogy with purpura. Here, however, is found the almost constant history of heredity and the implication only of persons of the male sex. The disposition to bleed at all times upon the receipt of the smallest injury is quite unlike the suddenly-developed and transitory hemorrhages of purpura, which are also more generally distributed.
With the secondary hemorrhagic effusions and ecchymoses that occur in conditions of profound alterations of the blood and blood-vessels in cases of malignant small-pox, scarlatina, typhus fever, etc., and in some cases of poisoning, as from phosphorus, spontaneous purpura presents identities, but the history of the complaint and the condition of the patient will prevent error. A knowledge of the circumstances will serve to distinguish purpura simplex from the petechiæ and small ecchymoses produced by fleas, by diminished atmospheric pressure, by coughing, in the course of Bright's disease, etc.
Purpura rheumatica presents, as has been shown, many points of resemblance to erythema multiforme and erythema nodosum. The mild fever, the joint-pains, the extravasations of the latter affections, are much like the symptoms of this form of purpura. The nodular, inflamed, tender condition of the lesions, their location—frequently upon the extensor surfaces of the extremities—their course and duration, usually serve to identify erythema nodosum, while with erythema multiforme it is usually not difficult to observe its essentially inflammatory character. Scheby-Buch has shown the difficulties often opposed to the differentiation of purpuric lesions and ecchymoses due to violence.15 Where the petechial eruption of purpura simplex is well marked, where the internal hemorrhages of purpura hæmorrhagica are copious, the inquiries of the observer will usually lead him to correct conclusions. Where the ecchymoses are larger and upon exposed parts of the body, the diagnosis from the lesions alone becomes impossible, and due consideration of all concomitant circumstances is essential. It should be remembered that in purpura very slight violence may call forth extensive ecchymosis. This circumstance has important medico-legal bearings.
15 Viertelj. f. Dermatol. und Syph., 1879, p. 99.
PROGNOSIS.—Purpura usually terminates favorably. Its course runs from two to six weeks, rarely longer. Relapses and remissions are frequent. Purpura simplex is of very little gravity, and need excite little apprehension. Purpura rheumatica almost always ends in recovery; fatal terminations, however, have been known. Purpura hæmorrhagica is of much more serious import. Even here, however, though the patient may fall into profound debility from loss of blood, recovery is the rule, the symptoms gradually diminishing in severity until health becomes re-established. In fatal cases death ensues after prolonged and profuse losses of blood. Purpura may subside after a single outbreak or many relapses, and recrudescences may occur extending through months. Anæmia may persist long after the disappearance of purpuric symptoms. A tendency to purpura may be shown at irregular intervals for years, and even throughout life.
TREATMENT.—Very mild cases of purpura simplex require no treatment, not even confinement within doors. The patient is often first made aware of his disease by accident; doubtless it frequently escapes detection altogether. It has been observed that purpura often appears upon the lower limbs of convalescents from other diseases when they first essay the upright position. Relapses of purpura also frequently appear as the patient leaves his bed. We have here an important indication for treatment—viz. the maintenance of the recumbent posture in cases of any degree of severity. Fresh vegetables and vegetable acids do not have the same happy influence as in scurvy. It is manifestly important that appropriate food should be administered in sufficient quantity, both to improve the general health and to repair the exhausting losses of blood. Milk is an exceedingly valuable article of diet in these cases, being but little apt to irritate the mucous membrane of the alimentary canal.
The patient should be guarded against violence. Injuries that may be of no consequence to healthy persons may excite in the purpuric profuse hemorrhage, free or interstitial. Violent emotions and physical efforts should be avoided, as in stimulating the heart's action a condition of increased blood-pressure ensues that may readily result in extravasation.
There are no remedies that exert a specific influence over purpura, and yet quite a number have enjoyed, and still enjoy, high reputation in controlling the symptoms. Probably the most frequently employed remedy against purpura is sulphuric acid, preferably the aromatic sulphuric acid, in doses of from 15 to 20 drops, diluted well with water and administered every third or fourth hour. It is certainly an agent of value, though some authors maintain that it has no efficacy (Immermann). Acetate of lead undoubtedly exercises an influence over the course of the disease. More recently, ergot has been employed. Its use has been highly extolled by Buckley and others. Very large doses may be given. The hypodermic use of ergotin has been followed by results most gratifying to those employing it. Oil of turpentine has enjoyed considerable reputation. A remedy that undoubtedly has a good effect is iron, both as exercising a controlling action over the bleeding and as assisting to repair the resulting anæmia. The tincture of the chloride is the most suitable preparation, and may be given in large doses (from minim xx to fluidrachm ss), well diluted, every fourth hour. Care must be exercised to avoid irritating the digestive organs with it. Formerly, venesection was employed to prevent the occurrence of hemorrhage, but its efficacy in this direction is at least doubtful, and cannot but help to intensify the disastrous consequences of severe and protracted attacks.
The various complications that may arise, as well as the general results of purpura, must be treated symptomatically. For the mucous membranes astringent washes should be used, and in favorable situations the tampon may sometimes be employed with profit. In purpura rheumatica the arthritic pains will be alleviated by anodyne liniments and plasters, and the often accompanying abdominal pains and colic by anodynes internally administered. Hæmatemesis, hæmaturia, etc. must be treated upon general principles. The results of profuse hemorrhage must be combated with stimulants. Transfusion of blood has been proposed and practised for the extreme anæmia that sometimes occurs, but without encouraging results. If necessary, the bowels may be kept free by mild aperients. In severe cases rest in bed should be rigidly enforced until after the establishment of convalescence. Quinia, iron, and nux vomica are indicated above all other remedies for the anæmia resulting from an attack of purpura.