Pernicious anemia is characterized by the presence of an unusually small number of red blood-cells. In average cases they count approximately 1,000,000 to the cubic millimeter. Simply a great reduction in the red corpuscles is not enough, however, to establish a diagnosis of the malady. A large number of megaloblasts is particularly pathognomonic. Usually as many as one-third or more of the red cells are of this large variety. The red corpuscles vary much in shape and are frequently unusually small as well as large. Nucleated cells are commonly seen. Many do not stain evenly, and in others the hemoglobin is not uniformly distributed. Evidences of degeneration are common. The white cells are reduced in number.

Hemoglobin, although less abundant than in normal blood, occurs in larger proportion than do the red corpuscles, or at least falls little below what would be expected because of the reduction in corpuscles. The amount of hemoglobin is usually high in proportion as megaloblasts are numerous. So great a degree of anemia is naturally accompanied with pallor, feebleness, palpitation on exertion, shortness of breath, and often dizziness or faintness.

Digestion is frequently impaired. Nausea and vomiting occur from time to time in most cases. Constipation is the rule. The kidneys act normally, but the urine commonly contains an unusually large amount of indican and other ingredients indicative of putrefaction of the contents of the intestine. Sometimes the sternum and long bones are tender. Frequently the heart is dilated; anemic murmurs are audible over it and the large vessels. Ocular and cerebral hemorrhages are occasional complications. Spinal degeneration irregularly distributed causes paresthesia and sometimes exaggerated reflexes and unsteadiness in walking or inability to do so. The hands may be similarly effected though usually they are less frequently and less severely involved than the legs and feet. These spinal symptoms develop sooner or later in almost every case.

Causes

The pathogenesis of the disease is unknown. There are two groups of cases; one in which the anemia is secondary, and another in which it is apparently primary. As the syndrome does not develop in every case in which, so far as our knowledge goes, it might be expected to, it seems probable that a predisposition to the malady may exist. Prolonged mental harassment, physical exertion which is prolonged and excessive, and too little or improper food are conditions which apparently dispose one to it.

Such intestinal parasites as bothriocephalus, ankylostoma, and, rarely, ascarides, cause the disease. It is also known to be due to malarial and syphilitic infection. Atrophy of the gastric glands, either with or without carcinoma of the stomach, is frequently associated with pernicious anemia and is suspected to be causative of it. In most cases an unusual amount of putrefaction in the contents of the intestine is demonstrable, and Hunter regards toxins thus generated as the cause of the disease. From the fact that iron is deposited in large amounts in the periphery of the liver lobules, as happens when corpuscles are experimentally destroyed in large numbers in the portal vessels, this theory seems plausible.

Anemia of this kind develops not infrequently during or immediately after pregnancy, and it occasionally follows repeated hemorrhages.

Treatment

So far as it is possible the conditions that predispose to pernicious anemia and the infections that cause it must be removed or counteracted.

Ferruginous preparations are of little value; this is also true of bone-marrow, which was widely used a few years ago. Transfusion of blood has given negative results in almost every case. The drugs which produce positive effects and possess real value in the treatment of the ailment are arsenical preparations and intestinal antiseptics.

Those foods should be chiefly used which are least liable to putrefy in the intestine. Milk is the best. It should form the basis of all food for these patients. As the disease is chronic, the diet must be varied somewhat. During the periods of greatest severity a milk diet may be maintained for a week or ten days. It may, as improvement begins, be supplemented by eggs and by meat from which fat and most of the connective-tissue fibers have been removed, or in which they are least abundant, as in squab, young chicken, fish, and oysters. Stale bread, oranges, stewed fruits, and fruit-juices are also permissible. From time to time, and especially in the mildest cases and when improvement is progressing, the diet can be varied much more than this.

Patients should be urged to drink water freely in order to dilute toxins and eliminate them rapidly. The bowels must be made to move regularly and copiously. The mouth and teeth must be kept scrupulously clean.

Now and again, anorexia or nausea and vomiting interfere with the administration of as much food as is needed. It is sometimes best to give the stomach a rest for a few days and to feed by the rectum. Lavage helps in many cases, especially when there are structural lesions in the stomach. A disinclination for food is best overcome by administering a little, often. Milk is then the best food. It should be given every two hours in portions of from one glass to half a glass or less. In these cases the administration of a sufficient amount of food is very difficult. Recourse must often be had to the employment of aids to digestion such as pepsin, hydrochloric acid and diastase, or predigested foods must be used.

Patients should be kept quiet upon the bed or couch. If it is necessary to move them, in all severe cases this should be done by the nurse. Active exertion on their part not only exhausts them, but, because of the feebleness of the heart, is often dangerous.

They should be kept in large, well-ventilated rooms, or, if the weather permits, out-of-doors. Sponging, an alcohol bath, and gentle rubbing are grateful and useful. Patients must be wrapped in warm clothing, for they feel the cold keenly, and are especially liable to those maladies which are caused by exposure to cold and dampness.