Different Staining Methods in Diagnosing Lophomonas blattarum in Bronchoalveolar Lavage Samples

Introduction:lophomonas blattarum is a multi-flagellate protozoan that causes bronchopulmonary infection in humans. as the culture and molecular diagnosis of lophomonas blattarum have not yet been developed, direct slide examination from nasopharyngeal secretions and bronchoalveolar lavage (bal) is the best method for the detection of lophomonas with morphological features. in the present study, to achieve quick and easy identification of lophomonas, the sensitivity of different staining techniques was compared with the direct wet slide as the gold standard. giemsa, trichrome, and papanicolaou stained slides have been examined in patients who had lophomoniasis. materials and methods:the bal samples of patients suspected of lophomoniasis were collected. after confirmation of lophomonas blattarum by observation in the direct test, the slides were prepared using giemsa, trichrome, and papanicolaou staining for each patient.results:among the 158 bal specimens sent to the laboratory of imam reza hospital, mashhad university of medical sciences, mashhad, iran, 50 samples were positive by direct microscopic examination that were stained by giemsa, trichrome, and papanicolaou techniques. the highest sensitivity was seen for papanicolaou staining with 16%, followed by giemsa and trichrome staining with 12% and 8%, respectively. conclusion:the findings of the present study indicated that the papanicolaou staining technique had the best sensitivity, compared to giemsa and trichrome stained slides for differential diagnosis of this protozoan from epithelial cells.