Weltmann coagulation reaction in rheumatoid arthritis.

Oskar Weltmann (1930) showed that human blood serum diluted in distilled water in the proportion of 1 :50 does not become turbid at the temperature of boiling water. In the Weltmann reaction the degree of flocculation depends on the addition of electrolytes through heat. Thus, varying with the pathological process, the diluted serum needs different quantities of bivalent electrolytes for the hot flocculation to take place. Bonilla and Lagrotta explained that if, instead of using distilled water, we proceed to the dilution of serum in ordinary water or in normal saline, we will succeed in promoting flocculation in normal serum, provided that adequate concentrations of an electrolyte are present-as, for example, calcium, barium, or magnesium chloride, ammonium sulphate, etc. Weltmann, taking this fact as a basis, developed a technique for the determination of the " electrolytic threshold " of the sera and the alterations which it may suffer in various pathological conditions. In order to produce a flocculation, it is, therefore, necessary to add larger calcium chloride concentrations to the serum of exudative processes than to normal serum. In the presence of hepatic cirrhosis and chronic proliferative diseases, a smaller amount of electrolyte is necessary. The mechanical working of this reaction seems to depend not on a close relationship with the total proteins of the serum, nor on the serum albumin-globulin ratio, but on the qualitative modifications of the serum proteins caused by the tissue alterations originating from exudative or fibrotic processes. There are in the literature only two papers on the employment of the Weltmann test in rheumatoid arthritis. They are those of Milles and Salt, and of Kling, both published in 1941. Milles and Salt, in 150 cases of rheumatoid arthritis, investigated the erythrocyte sedimentation rate, the formol-gel test, and the Weltmann and Takata-Ara reactions, and concluded that the sedimentation rate and the Weltmann reaction are extremely sensitive indices of the severity of the complaint, although the results of the two tests are not always parallel. In some patients with a serious form of rheumatoid arthritis the shift of the flocculation band toward the left was moderate. Kling, after investigating 98 cases of rheumatoid arthritis, also concluded that the Weltmann reaction does not possess the same sensitiveness as the sedimentation rate, which appeared to him to be a more exact index of the clinical progress of the disease, and of the therapeutic results. In his cases a marked narrowing of the flocculation band occurred only in 53%, while the sedimentation rate showed an increase in 82%. It appears that the meaning of the serum flocculation band in rheumatic diseases has not yet been investigated sufficiently. Severe rheumatoid arthritis seems to be characterized by a moderate shift to the left of the serum flocculation band. This shift to the left should be much more marked in the acute stage of rheumatic fever. A shift to the right has also been recorded in a few cases of rheumatoid arthritis, and when this is so the prognosis would appear to be good.