Bronchopulmonary lophomoniasis in a prisoner: A case report

Background: Bronchopulmonary lophomoniasis, an emerging yet frequently overlooked respiratory infection, is caused by the flagellated protozoan Lophomonas blattarum (L. blattarum). Although predominantly observed in immunocompromised individuals, its occurrence in immunocompetent hosts, particularly within high-risk settings like correctional facilities, is uncommon. Case Presentation: This report details the case of a 47-year-old male prisoner from Golestan Province, Iran, who presented with a four-month history of chronic cough, dyspnea, and purulent sputum. The initial diagnostic workup, including blood and sputum cultures, yielded no evidence of bacterial or fungal infection. However, microscopic examination of bronchoalveolar lavage (BAL) fluid revealed L. blattarum trophozoites, leading to a definitive diagnosis of lophomoniasis. Of particular interest was the elevated serum immunoglobulin E (IgE) level (387 kU/L; normal range <160 kU/L), which may indicate an underlying allergic predisposition or a concurrent parasitic infection. The patient's symptoms resolved completely after a four-week regimen of metronidazole. Conclusion: This case highlights the importance of considering lophomoniasis in the differential diagnosis of chronic respiratory symptoms, especially in settings with poor hygiene. For accurate diagnosis in similar patient populations, a heightened clinical suspicion combined with BAL microscopy are essential.