[Inappropriate antidiuretic hormone secretion syndrome associated with a pleuropulmonary infection].

A case of pleuropulmonary infection without a demonstrable causal agent associated to inappropriate secretion of antidiuretic hormone is reported. Although antidiuretic hormone levels were not measured, unequivocal indirect proof of elevated levels was present as evidenced by characteristic serum and urinary electrolyte abnormalities, other possible causes having been carefully ruled out. The hyposmolar clinical picture was refractory to conservative measures, and it was corrected only when a loculated empyema was surgically drained by way of thoracotomy. The literature on inappropriate secretion of antidiuretic hormone related to pleuropulmonary pathology is briefly reviewed. Particular emphasis is made on the pleural encapsulation in the present case as the factor responsible for perpetuation of pulmonary infection and origin of the hormonal disturbance.