Blood Examinations in Hay Fever Patients During Acute Allergic Shock

Abstract

Allergic shock in tnan comes unexpectedly in most cases, or at any rate under conditions prohibiting exact examination of the composition of the blood while the shock lasts; as a result, our knowledge of any changes there may be in the state of the blood during allergic shock rests upon a relatively slender foundation.In animals, anaphylactic shock is generally considered to be analogous to allergic shock in man; the pathogenesis is assumed to be the same in both reactions: an antigen-antibody reaction liberates a histamine-like substance which thereupon induces the local and general symptoms (4, 6). It should be observed, however, that in anaphylactic shock the symptoms may vary considerably from one kind of animal to another, just as in man the allergic shock has no uniform symptomatology. Finally, the liberation of histamine (or H-substance) will not suffice as an explanation of all symptoms, and it is assumed that other humoral intermediaries (heparine, acetylcholine) are also active.In anaphylactic shock (in animals) there occurs a sudden change in the permeability of the capillaries and in the tone of the smooth muscles in various organs; this rapidly involves changes in the blood pressure, respiration and the chemical and cytological composition of the blood.For example, there may be a greater or smaller fall in the blood pressure (7), haemoconcentration, together with a decrease in the number of leucocytes and thrombocytes (5,6,8,9, 12,20, 21,22,28,29), and the coagulation time is prolonged (up to