Ascaris-induced eosinophilic pneumonitis in an HIV-infected patient

A case of Ascaris-induced eosinophilic pneumonitis in an HIV-infected patient is described. Owing to his HIV status and the absence of peripheral blood eosinophilia on admission, the initial diagnosis was incorrect until the passage of two worms in his stool. The patient developed eosinophilia subsequently, and examination of his sputum also showed increased eosinophils. The patient gradually improved with inhaled bronchodilators, steroid and mebendazole. As peripheral blood eosinophilia may be transient and the larval migration phase occurs before eggs are present in stool, a high index of suspicion is required in making the diagnosis of Ascaris pneumonitis. Examination of sputum for larvae or increased eosinophils should be performed in patients suspected of having pulmonary infiltrates from endemic areas irrespective of peripheral blood eosinophil counts.