Kapronczay Károly szerk.: Orvostörténeti Közlemények 190-193. (Budapest, 2005)

KÖZLEMÉNYEK - COMMUNICATIONS - Paskalev, Dobrin - Kircheva, Anna B.: Bulgarian contributions to the development of medicine - Bolgár hozzájárulások az orvostudomány fejlődéséhez

In the very beginning, Chilov noted from methodological point of view: "... we usually detect chlorides in the organism mostly in the form of NaCl.

.. and thus, speaking about chlorides we shall understand common salt" (p. 10). These lines reflect on the laboratory capacity of his time, when direct sodium (Na) measurement was not possible. Regardless of the existing methodological difficulties, Chilov pointed out: "... sodium and chloride are not always bound, and in some instances it is of importance to know the quantity of chloride and sodium separately..."(p. 10). The importance of salt and its constituent parts were postulated as follows: "NaCl is necessary for life, necessary moreover both with the cation and anion separately, put together or bound in certain proportion to other anions and cations" (p.29)(9). In the chapter entitled "Pathology of the common salt" a matter of interest are Chilov's own results proving hypochloremia (i.e. hyponatremia) in patients suffering from pneumonia and pulmonary tuberculosis. The clinical improvement observed in these cases has been related to disappearance of the biochemical disturbance. Now, 70 years later, the event described by Chilov could be explained with the so-called syndrome of inappropriate vasopressin secretion (SIADH), leading to decreased sodium level in the blood. It is known that some of the most common causes for the development of SIADH are the pulmonary infections (13, 14). The pathogenesis remains unclear, but one possible explanation is that increased pulmonary vascular resistance leads to decreased left atrial baroreceptors. On the other hand, the cytokines, released in the inflammatory response during the infection, could cause a downward resetting of the osmostat (15). The final result is increased vasopressin secretion leading to hyponatremia. Chilov described also hypochloremia (i.e. hyponatremia) in cases of typhus abdominalis, a condition aggravating the course of the disease. Together with the Prof. V. Alexiev (physician and pharmacologist), he proposed as therapeutical manoeuvre the additional intake of salt and hydrochloric acid in the form of the so-called "lemonade hydrochlorica" (P.73-74X9). Common salt as poison This chapter revealed the negative consequences in the organism if it is loaded with salt. The author concluded: "... common salt taken by means of food can be also poison but the compounds, which are antagonists to this poison, neutralize its effect in a healthy organism. However, when sodium antagonists such as calcium, potassium and magnesium are exhausted in the cells, the organism becomes diseased" (p.94)(9). Chilov's view that salt abuse and electrolyte disturbances can lead to disease has been well illustrated with the contemporary knowledge on hypertension. Several epidemiological studies have demonstrated that prevalence of hypertension is greater in population on a higher salt diet. Indeed, the INTERSALT study shows the positive correlation of the incidence of hypertension to the amount of salt intake among people in 34 different countries. On the other hand, it has been demonstrated that potassium (K) can ameliorate a salt-induced rise in blood pressure and salt-induced cardiovascular damages by inhibiting the sympathetic