Pulmonary function in tropical eosinophilia before and after treatment with diethylcarbamazine

Spirometric and lung volume measurements were carried out before and after treatment with diethylcarbamazine in 19 patients with tropical eosinophilia. The total lung capacity and vital capacity returned to or nearly to normal while the FEV1 and PEFR, though improved, tended to remain below normal, indicating some residual airways obstruction especially in patients whose treatment began more than one month from the onset of symptoms. The time taken for the pulmonary function to return to normal with treatment was found to be much longer than for the clinical and haematological response.