Are Pediatric Infections with Lophomonas blattarum Being Missed?

Pulmonary infection by Lophomonas spp. and Aspergillus spp. in a B-cell acute lymphocytic leukemia patient from Chile

The flagellated protozoan Lophomonas spp. is a commensal microorganism found in the intestinal tracts of cockroaches, termites, mites, and certain birds. It is the causative agent of a rare infection in humans called lophomoniasis, primarily affecting the lungs and mainly immunocompromised individuals. This parasitosis is transmitted to humans by air or through ingestion of the cystic forms of the parasite. We describe the case of a 50-year-old patient treated at a tertiary hospital in southern Chile with a history of B-cell acute lymphocytic leukemia. Radiological findings, along with increased levels of inflammatory parameters and galactomannan antigen in serum and Bronchoaveolar Lavage (BAL) raised the suspicion of a pulmonary infection. Microscopic study of BAL revealed oval to pyriform cells with mobile flagella at the anterior end, which were identified as Lophomonas spp. trophozoites, which based on EORTC/MSG criteria were associated with diagnosis of a probable pulmonary aspergillosis. Lophomoniasis was treated with metronidazole (500 mg IV every 8 h) for 14 days and pulmonary aspergillosis required a combination of fluconazole, voriconazole, anidulafungin, liposomal amphotericin B and isavuconazole. The patient responded favorably and was discharged after 95 days of hospitalization. This case highlights the importance of recognizing lophomoniasis as a parasitic infection in respiratory samples from immunocompromised patients who present pulmonary symptoms, especially those who do not respond satisfactorily to conventional antimicrobial treatments. Further research is needed to understand the various sources of Lophomonas spp. infection and develop infection prevention strategies particularly for high-risk patients.

Fiberoptic Bronchoscopic Findings in Patients Suffering from Emerging Pulmonary Lophomoniasis: A First Registry-Based Clinical Study

Background

Lophomonas blattarum is an emerging protozoan agent that mainly infects the lower respiratory system, causing pulmonary lophomoniasis. The bronchoscopic findings in patients with pulmonary lophomoniasis have not been investigated yet. Accordingly, we assess the bronchoscopic findings of lophomoniasis in patients suffering from pulmonary lophomoniasis through a registry-based clinical study.

Methods

In this retrospective study, of 480 patient candidates for bronchoscopy, 50 Lophomonas-positive patients were enrolled. Demographic data, relevant characteristics, and bronchoscopy findings of the patients were recorded and analyzed.

Results

Overall, 50 (male = 32, female = 18) patients with an average age of 61.8 ± 13.3 years were examined. Nineteen patients (38%) had normal bronchoscopic findings, and 31 patients (62%) had abnormal bronchoscopic findings. According to the severity index, most (52%) of patients had mild severity, followed by moderate (30%) and severe (18%) cases. The highest involvement was in the right lung bronchus (46%), and the lowest was in the carina (8%). Furthermore, purulent and mucosal secretions in the right and left lung bronchus were the most abnormalities found in different anatomical locations.

Conclusion

For the first time, the current study demonstrated that pulmonary lophomoniasis does not have pathognomonic bronchoscopic findings. However, each suspected patient must be checked for lophomoniasis, even with normal bronchoscopic findings, particularly in endemic areas.