Definition And Description

Purpura is an affection due to localized effusions of blood into the skin, and is characterized by the sudden appearance of small macules from one-twelfth to one-half inch in diameter on various parts of the surface. A comparatively small number only may be present, or, on the other hand, so many that it would prove tedious to count them. The spots, at the moment of their first appearance, are rod, hut soon assume a purplish hue. The color is not removable by pressure. After a few days they undergo the changes of color that we are all familiar with in connection with ecchymoses from contusion.

The eruption may be thickly sprinkled over the whole surface, except the face and scalp, which are usually spared. The macules may all appear in a single day, or additions may occur for several successive da\ The spots go through their changes and disappear in from one to two weeks. After a variable period a fresh crop may appear, and this may be repeated a number of times.

In some cases hemorrhage from the mucous surfaces takes place, and may be so profuse as to seriously endanger the life of the patient.

In simple Purpura there is, as a rule, a total absence of constitutional symptoms - that is, there is no febrile action either before or after the eruption. There is also absence of pain and itching. The eruption may attack those in a debilitated condition, or those who appear to be in perfect health.

Purpura hemorrhagica, on the other hand, may be preceded by a vague feeling of illness, but without well-defined symptoms. As the disease advances, however, hemorrhages from the nose, mouth, bowels, or bladder may produce serious debility and even prove fatal.

Diagnosis

The diagnosis of purpura is easy, the only affection with which the inexperienced would be likely to confound it being Scurvy. In Scurvy the gums are swollen and may be ulcerated, and the purple spots are not mere macules but patches of considerable size. In Scurvy there is also swelling of the lower limbs, not a soft oedema, such as occurs in Bright's disease, but a hard, boardy feeling that is hardly met with in any other affection. In Scurvy it is usual also to have more or less debility. The history of the case will also throw light on the diagnosis. Purpura usually comes on without assignable cause, while Scurvy is always the result of improper diet, such as exclusive confinement to salt food, absence of vegetables, etc.

Prognosis

In simple purpura the prognosis is usually good, but in the hemorrhagic form there is danger of exhaustion and collapse fro loss of blood. The effusions may also invade the tissues of the internal organs, and in this way interfere with the performance of vital functions.

Etiology

We may frankly say that we do not know the causes that bring about this affection. The disease consists essentiallyin an effusion of blood from ruptured cutaneous capillaries, or possibly to diapedesis of the red corpuscles, without rupture of the vessel. As immediate causes of this condition some have asserted that the blood was thinner than usual, others that the blood was normal, but that the capillaries were weakened. Both of these assigned causes are theoretical and not based on known facts. Various remote causes have also been suggested, as liepatic congestion (Cauty), internal obstruction (Bateman), enlarged spleen (Fuchs), debility of the nervous powers (Wilson), deficient or suppressed menstruation (Care nave), etc. The last-mentioned cause we have seen exemplified in a case in which the purpura partook of the nature of various menstruation, coming on for several months, at the time of, and instead of the natural flow.

Treatment

The most varied treatment has been recommended for this affection - for instance, iron in large doses, in order to repair the supposed deficiencies in the blood: tannin, gallic acid, the mineral acids, etc., under the idea that they would act as astringents, and many other methods equally irrational and useless.

More recently, however, it has been discovered that Ergot possesses the most undoubted influence over this affection, and if given sufficiently early and in full doses is capable of bringing it to an early termination. It may be administered by the mouth or hypodermically.

The following drugs may also be referred to: Acidum Salicylicum. 10; Ferri Arsenias, 54; Krameria, 72; Potassii Nitras, 95; Rumea Acetosa, 101; Terebinthina, 110.