The Syndrome of Inappropriate Secretion of Antidiuretic Hormone in Infectious Pulmonary Disease

Three cases of infectious pulmonary disease associated with hyponatremia resulting from the inappropriate secretion of antidiuretic hormone are described. The pathogenesis of this syndrome as it is seen in chest disease is discussed. A case of this syndrome occurring with allergic bronchopulmonary aspergillosis is reported. The rarity of symptomatic hyponatræmia in pulmonary tuberculosis and the usual response to chemotherapy are described. The danger of fluid restriction in patients with airways obstruction is emphasized, and a conservative approach to the management of the syndrome recommended.