True molecular phylogenetic position of the cockroach gut commensal Lophomonas blattarum (Lophomonadida, Parabasalia).

Lophomonas blattarum is a facultative commensal gut dweller of common pest cockroaches. Its cells are roughly spherical in shape with an apical tuft of ~50 flagella. Controversially, it has been implicated in human respiratory infections based on light microscopic observations of similarly shaped cells in sputum or bronchoalveolar lavage fluid. Here, we have sequenced the 18S rRNA gene of L. blattarum and its sole congener, Lophomonas striata, isolated from cockroaches. Both species branch in a fully supported clade with Trichonymphida, consistent with a previous study of L. striata, but not consistent with sequences from human samples attributed to L. blattarum.

Molecular phylogeny of Spirotrichonymphea (Parabasalia) with emphasis on Spironympha, Spirotrichonympha, and three new genera Pseudospironympha, Nanospironympha, and Brugerollina.

Spirotrichonymphea, one of the six classes of phylum Parabasalia, are characterized by bearing many flagella in spiral rows, and they occur exclusively in the guts of termites. Phylogenetic relationships among the 13 described genera are not well understood due to complex morphological evolution and a paucity of molecular data. One such understudied genus is Spironympha. It has been variously considered a valid genus, a subgenus of Spirotrichonympha, or an "immature" life cycle stage of Spirotrichonympha. To clarify this, we sequenced the small subunit rRNA gene sequences of Spironympha and Spirotrichonympha cells isolated from the hindguts of Reticulitermes species and Hodotermopsis sjostedti and confirmed the molecular identity of H. sjostedti symbionts using fluorescence in situ hybridization. Spironympha as currently circumscribed is polyphyletic, with both H. sjostedti symbiont species branching separately from the "true" Spironympha from Reticulitermes. Similarly, the Spirotrichonympha symbiont of H. sjostedti branches separately from the "true" Spirotrichonympha found in Reticulitermes. Our data support Spironympha from Reticulitermes as a valid genus most closely related to Spirotrichonympha, though its monophyly and interspecific relationships are not resolved in our molecular phylogenetic analysis. We propose three new genera to accommodate the H. sjostedti symbionts and two new species of Spirotrichonympha from Reticulitermes.

Morphological and Molecular Identification of Emerged Lophomonas blattarum Infection in Mazandaran Province, Northern Iran: First Registry-Based Study.

BACKGROUND: In the last decade, several cases of bronchopulmonary lophomoniasis (BPL) have been recorded. Little information is available about epidemiological aspects on Lophomonas infection among BPL patients. The present study was aimed to investigate the prevalence of Lophomonas spp. infection in patients who were referred to the Iranian National Registry Center for Lophomoniasis (INRCL), using morphological and molecular tests. SUBJECTS AND METHODS: We examined patients enrolled in the INRCL from 2017 to 2019 at the Mazandaran University of Medical Sciences, northern Iran. All bronchoalveolar lavage fluid (BALF) and two nasal discharges of the patients were examined by both microscopic and small-subunit ribosomal RNA (SSU rRNA) PCR methods. To confirm the species of Lophomonas, two positive samples were sequenced. RESULTS: In this study, 321 specimens (including 319 BALF and 2 nasal discharges) were microscopically examined. Lophomonas spp. was found in 45(14%) (n = 44 BAL; n = 1 nasal discharge). The mean age of infected patients was 54.9 ± 17.1 years. The following morphological characteristics were observed in both fresh and Papanicolaou-stained smears to identify Lophomonas spp. All microscopically positive specimens were confirmed with genus-specific PCR technique. The obtained sequences were deposited in Gen Bank under the accession numbers (MN243135-36). The BLAST analysis of our two sequences with the only available sequence in the Gen Bank of the Thailand strain of L. blattarum, showed identity of 99-100% and 98.51%, respectively. CONCLUSION: To the best of our knowledge, this is the first registry-based study regarding lophomoniasis worldwide. According to our study, the conventional PCR test is an available and reliable tool for confirming the Lophomonas parasite in clinical samples. Moreover, the results confirmed that L. blattarum is circulating at least in our region.

Characterization of new cristamonad species from kalotermitid termites including a novel genus, Runanympha.

Cristamonadea is a large class of parabasalian protists that reside in the hindguts of wood-feeding insects, where they play an essential role in the digestion of lignocellulose. This group of symbionts boasts an impressive array of complex morphological characteristics, many of which have evolved multiple times independently. However, their diversity is understudied and molecular data remain scarce. Here we describe seven new species of cristamonad symbionts from Comatermes, Calcaritermes, and Rugitermes termites from Peru and Ecuador. To classify these new species, we examined cells by light and scanning electron microscopy, sequenced the symbiont small subunit ribosomal RNA (rRNA) genes, and carried out barcoding of the mitochondrial large subunit rRNA gene of the hosts to confirm host identification. Based on these data, five of the symbionts characterized here represent new species within described genera: Devescovina sapara n. sp., Devescovina aymara n. sp., Macrotrichomonas ashaninka n. sp., Macrotrichomonas secoya n. sp., and Macrotrichomonas yanesha n. sp. Additionally, two symbionts with overall morphological characteristics similar to the poorly-studied and probably polyphyletic 'joeniid' Parabasalia are classified in a new genus Runanympha n. gen.: Runanympha illapa n. sp., and Runanympha pacha n. sp.

Protozoan Cysts in Faecal Pellets of German Cockroaches (Blattella germanica), with Particular Emphasis on Lophomonas blattarum.

PURPOSE: The aim of this study was to investigate protozoan cysts and oocyts in the faecal pellets of the German cockroach (Blattella germanica), with emphasis on the prevalence of Lophomonas blattarum. METHODS: Thirty adult Blattella germanica (12 males; 18 females) were trapped near Madrid, Spain. Expelled faecal pellets were collected in the laboratory over 5 days in two plastic containers. Protozoan cysts from one container were weighted and those in the other used for morphologically identification. RESULTS: Protozoan cysts/oocysts per gram of faecal pellet were: Nyctotherus sp. (0.0019/g), Entamoeba (0.0007/g), Balantidium coli (0.0001/g), Lophomonas blattarum (0.00038/g). Observation of 189 protozoan cysts/oocysts indicated the following prevalence: Nyctotherus sp. 65 (34.4%); Gregarina spp. 34 (18%); Entamoeba sp. 24 (12.7%); Cryptosporidium sp. 17 (9%); Coccidia 16 (8.4%); Lophomonas blattarum 13 (6.8%); Balantidium coli 4 (2.1%); and unclassified 16 (8.4%). CONCLUSION: Lophomonas blattarum has previously been demonstrated in the gut of cockroaches, but this is the first assessment of the prevalence in Blattella germanica in faecal pellets. The presence of protozoa in faecal pellets provides some evidence for one step in a hypothesised route of respiratory infection whereby protozoa from household insects enter the respiratory tract.

Molecular characterization of Histomonas meleagridis exoproteome with emphasis on protease secretion and parasite-bacteria interaction.

The exoproteome of parasitic protists constitutes extracellular proteins that play a fundamental role in host-parasite interactions. Lytic factors, especially secreted proteases, are capable of modulating tissue invasion, thereby aggravating host susceptibility. Despite the important role of exoproteins during infection, the exoproteomic data on Histomonas meleagridis are non-existent. The present study employed traditional 1D-in-gel-zymography (1D-IGZ) and micro-LC-ESI-MS/MS (shotgun proteomics), to investigate H. meleagridis exoproteomes, obtained from a clonal virulent and an attenuated strain. Both strains were maintained as mono-eukaryotic monoxenic cultures with Escherichia coli. We demonstrated active in vitro secretion kinetics of proteases by both parasite strains, with a widespread proteolytic activity ranging from 17 kDa to 120 kDa. Based on protease inhibitor susceptibility assay, the majority of proteases present in both exoproteomes belonged to the family of cysteine proteases and showed stronger activity in the exoproteome of a virulent H. meleagridis. Shotgun proteomics, aided by customized database search, identified 176 proteins including actin, potential moonlighting glycolytic enzymes, lytic molecules such as pore-forming proteins (PFPs) and proteases like cathepsin-L like cysteine protease. To quantify the exoproteomic differences between the virulent and the attenuated H. meleagridis cultures, a sequential window acquisition of all theoretical spectra mass spectrometric (SWATH-MS) approach was applied. Surprisingly, results showed most of the exoproteomic differences to be of bacterial origin, especially targeting metabolism and locomotion. By deciphering such molecular signatures, novel insights into a complex in vitro protozoan- bacteria relationship were elucidated.

[Lung infection by lophomonas spp. in a female patient with acute myeloid leukemia]. / Infección pulmonar por Lophomonas sp en una paciente con leucemia mieloide aguda.

Protozoic infections are prevalent worldwide, particularly in immunosuppressed patients. We reported the case of a patient from the city of Viña del Mar, Chile, a carrier of acute myeloid leukemia in whom an infection by Lophomonas sp. was confirmed by bronchoalveolar lavage. She was treated with antibiotics but died of complications of the underlying disease. There is little literature available on this microorganism. We conclude that Lophomonas sp. should be considered as a diagnostic possibility if protozoa are found in bronchoalveolar lavage of immunosuppressed patients.

Las infecciones por protozoos son prevalentes a nivel mundial, en particular en pacientes inmunosuprimidos. Comunicamos el caso de una paciente procedente de la ciudad de Viña del Mar, Chile, portadora de leucemia mieloide aguda en quiense confirmó una infección por Lophomonas sp. en lavado bronquioalveolar. Se manejó con antibióticos, pero falleció decomplicaciones de su enfermedad de base. Existe poca literatura disponible respecto a este microorganismo. Concluimos que debe considerarse a Lophomonas sp. como posibilidad diagnóstica si se encuentran protozoos en lavados bronquioalveolares de pacientes inmunosuprimidos.

Infección pulmonar por Lophomonas sp en una paciente con leucemia mieloide aguda / Lung infection by lophomonas spp. in a female patient with acute myeloid leukemia

RESUMEN Las infecciones por protozoos son prevalentes a nivel mundial, en particular en pacientes inmunosuprimidos. Comunicamos el caso de una paciente procedente de la ciudad de Viña del Mar, Chile, portadora de leucemia mieloide aguda en quiense confirmó una infección por Lophomonas sp. en lavado bronquioalveolar. Se manejó con antibióticos, pero falleció decomplicaciones de su enfermedad de base. Existe poca literatura disponible respecto a este microorganismo. Concluimos que debe considerarse a Lophomonas sp. como posibilidad diagnóstica si se encuentran protozoos en lavados bronquioalveolares de pacientes inmunosuprimidos.

ABSTRACT Protozoic infections are prevalent worldwide, particularly in immunosuppressed patients. We reported the case of a patient from the city of Viña del Mar, Chile, a carrier of acute myeloid leukemia in whom an infection by Lophomonas sp. was confirmed by bronchoalveolar lavage. She was treated with antibiotics but died of complications of the underlying disease. There is little literature available on this microorganism. We conclude that Lophomonas sp. should be considered as a diagnostic possibility if protozoa are found in bronchoalveolar lavage of immunosuppressed patients.

Parasitic profiling of Japanese quails (Coturnix japonica) on two farms with conventional production system in the Amazon region / Perfil parasitário de codornas (Coturnix japonica) em duas granjas com sistema convencional de produção na Amazônia

The health monitoring and management systems of coturniculture can be deemed to be in a developmental phase when compared to the poultry industry. Studies regarding taxonomy and parasitic biology in quails (Coturnix japonica) has not been well conducted in Brazil. Most of the information is available from the autopsy case reports, in many ways the parasitic fauna of quails is still unknown. The aim of this study was to conduct a parasitological research in quails in order to contribute to ameliorate this situation. 31 quails, which were 12 months old, were used for the study. Their carcasses and viscera were sent to the Laboratory of Entomology and Tropical Diseases, INPA, Manaus/AM. The circulatory, nervous, respiratory, digestive and reproductive systems of these were studied separately. No blood parasites were found, however, nine species of endoparasites were registered which were distributed among the classes Cestoda, Nematoda and Protozoa. The helminths were distributed in the duodenum, jejunum, ileum, cecum and oviduct. The cecum was found to be the most parasitized organ and contained a wide range of parasites having three species of protozoa and three species of nematodes. Six morphotypes of Eutrichomastix globosus were recorded, and some morphotypes were hyperparasitized with sporangia Sphaerita sp. in the cytoplasm. A large number of parasites were recorded in this study, as well as the protozoan Blastocystis hominis was first being observed for quail.(AU)

A coturnicultura conta com um monitoramento sanitário e sistemas de manejo ainda em desenvolvimento quando comparado à avicultura industrial. Pesquisas de taxonomia e biologia parasitárias em codornas (Coturnix japonica) são pouco realizadas no Brasil, sendo a maioria das informações disponíveis referentes a relatos de caso em achados de necropsia, portanto, em muitos aspectos a fauna parasitária de codornas é ainda desconhecida. Este trabalho teve por objetivo realizar uma pesquisa parasitológica em codornas em fim de postura. Para pesquisa foram disponibilizadas 31 codornas com idades de 12 meses. As carcaças e suas vísceras foram encaminhadas ao Laboratório de Entomologia e Doenças Tropicais INPA, Manaus/AM. Foram estudados separadamente os sistemas circulatórios, nervoso, respiratório, digestivo e reprodutivo. Das 31 codornas examinadas nenhuma apresentou hemoparasitos, contudo, foram registradas nove espécies de endoparasitos distribuídas entre as classes Cestoda, Nematoda e protozoários. Os helmintos distribuíam-se pelo duodeno, jejuno, íleo, cecos e oviduto. O ceco foi o órgão mais parasitado e com maior diversidade de parasitas, sendo três espécies de protozoários e três de nematóides. Foram registrados seis morfotipos de Eutrichomastix globosus, sendo que, alguns morfótipos estavam hiperparasitados com esporângio Sphaerita sp. no citoplasma. Uma grande variedade de parasitos foi registrada nesta pesquisa, bem como, o protozoário Blastocystis hominis pela primeira vez sendo descrito para codornas.(AU)

The prevalence of protozoa in the gut of German cockroaches (Blattella germanica) with special reference to Lophomonas blattarum.

The German cockroach (Blattella germanica) is a common domestic pest, which produces allergens that have been associated with broncho-pulmonary disease. Various protozoan species have been identified in the intestine of this cockroach and it has been hypothesised that these protozoa, or their proteases, may contribute to the burden of cockroach-associated allergens and adjuvants present in domestic dust. The aim of this study was therefore to determine the prevalence of protozoan species in the intestine of Blattella germanica. German cockroaches were anesthetised and dissected and gut contents are used to produce wet slides for microscopy. Both, Giemsa and Papanicolaou stains were used to confirm correct identification of Lophomonas blattarum. Representatives of four genera of protozoa were identified in 110 cockroaches: Nyctoterus sp. was observed in 91.8% of cases, Gregarina sp. in 64.5%, Amoeba sp. in 25.4% and Lophomonas blattarum in 13.6%. Nyctoterus and Gregarina were statistically significantly more likely to be found in diseased cockroaches compared to Amoeba or Lophomonas. The prevalence of Lophomonas blattarum was similar to that in published studies of a different species of cockroach, Periplaneta americana. Further work is needed to assess the interplay between protozoa, cockroaches and broncho-pulmonary diseases.

Genome Evolution and Nitrogen Fixation in Bacterial Ectosymbionts of a Protist Inhabiting Wood-Feeding Cockroaches.

UNLABELLED: By combining genomics and isotope imaging analysis using high-resolution secondary ion mass spectrometry (NanoSIMS), we examined the function and evolution of Bacteroidales ectosymbionts of the protist Barbulanympha from the hindguts of the wood-eating cockroach Cryptocercus punctulatus In particular, we investigated the structure of ectosymbiont genomes, which, in contrast to those of endosymbionts, has been little studied to date, and tested the hypothesis that these ectosymbionts fix nitrogen. Unlike with most obligate endosymbionts, genome reduction has not played a major role in the evolution of the Barbulanympha ectosymbionts. Instead, interaction with the external environment has remained important for this symbiont as genes for synthesis of transporters, outer membrane proteins, lipopolysaccharides, and lipoproteins have been retained. The ectosymbiont genome carried two complete operons for nitrogen fixation, a urea transporter, and a urease, indicating the availability of nitrogen as a driving force behind the symbiosis. NanoSIMS analysis of C. punctulatus hindgut symbionts exposed in vivo to (15)N2 supports the hypothesis that Barbulanympha ectosymbionts are capable of nitrogen fixation. This genomic and in vivo functional investigation of protist ectosymbionts highlights the diversity of evolutionary forces and trajectories that shape symbiotic interactions. IMPORTANCE: The ecological and evolutionary importance of symbioses is increasingly clear, but the overall diversity of symbiotic interactions remains poorly explored. In this study, we investigated the evolution and nitrogen fixation capabilities of ectosymbionts attached to the protist Barbulanympha from the hindgut of the wood-eating cockroach Cryptocercus punctulatus In addressing genome evolution of protist ectosymbionts, our data suggest that the ecological pressures influencing the evolution of extracellular symbionts clearly differ from intracellular symbionts and organelles. Using NanoSIMS analysis, we also obtained direct imaging evidence of a specific hindgut microbe playing a role in nitrogen fixation. These results demonstrate the power of combining NanoSIMS and genomics tools for investigating the biology of uncultivable microbes. This investigation paves the way for a more precise understanding of microbial interactions in the hindguts of wood-eating insects and further exploration of the diversity and ecological significance of symbiosis between microbes.

Identification criteria of the rare multi-flagellate Lophomonas blattarum: comparison of different staining techniques.

Bronchopulmonary lophomoniasis (BPL) is an emerging disease of potential importance. BPL is presented by non-specific clinical picture and is usually accompanied by immunosuppression. Culture of Lophomonas blattarum is difficult and its molecular diagnosis has not yet been developed. Therefore, microscopic examination of respiratory samples, e.g., bronchoalveolar lavage (BAL) or sputum, is the mainstay of BPL diagnosis. Creola bodies and ciliocytophthoria are two forms of bronchial cells which occur in chest diseases with non-specific clinical picture like that of BPL. Both forms could be misrecognized as multi-flagellates because of their motile cilia in the wet mounts and due to shape variability of L. blattarum in stained smears. The aim of the study is to compare different staining techniques for visualizing L. blattarum to improve the recognition and diagnosis of BPL, to distinguish respiratory epithelial cells from L. blattarum and to decide which stain is recommended in suspected cases of BPL. BAL samples from patients which contain L. blattarum, creola bodies, and ciliocytophthoria were collected then wet mounts were examined. The BAL samples were also stained by Papanicolaou (PAP), Giemsa, hematoxylin and eosin (H & E), trichrome, Gram, and Diff-Quik (DQ) stains. The different staining techniques were compared regarding the stain quality. In wet mounts, the ciliary movement was coordinate and synchronous while the flagellar movement was wavy and leaded to active swimming of L. blattarum. In stained slides, bronchial cells were characterized by the presence of basal nucleus and the terminal bar from which the cilia arise. Trichrome was the best stain in demonstration of cellular details of L. blattarum. H & E, PAP, and Giemsa stains showed good quality of stains. Gram and DQ stains showed only pale hues of L. blattarum. We recommended adding Wheatley's trichrome staining to the differential diagnosis workup of cases of non-specific chest infections, especially when BPL is suspected, to avoid overdiagnosis or underdiagnosis of it.

Molecular Evidence for the Polyphyly of Macrotrichomonas (Parabasalia: Cristamonadea) and a Proposal for Macrotrichomonoides n. gen.

Macrotrichomonas (Cristamonadea: Parabasalia) is an anaerobic, amitochondriate flagellate symbiont of termite hindguts. It is noteworthy for being large but not structurally complex compared with other large parabasalians, and for retaining a structure similar in appearance to the undulating membrane (UM) of small flagellates closely related to cristamonads, e.g. Tritrichomonas. Here, we have characterised the SSU rDNA from two species described as Macrotrichomonas: M. restis Kirby 1942 from Neotermes jouteli and M. lighti Connell 1932 from Paraneotermes simplicicornis. These species do not form a clade: M. lighti branches with previously characterised Macrotrichomonas sequences from Glyptotermes, while M. restis branches with the genus Metadevescovina. We examined the M. restis UM by light microscopy, scanning electron microscopy, and transmission electron microscopy, and we find common characteristics with the proximal portion of the robust recurrent flagellum of devescovinids. Altogether, we show the genus Macrotrichomonas to be polyphyletic and propose transferring M. restis to a new genus, Macrotrichomonoides. We also hypothesise that the macrotrichomonad body plan represents the ancestral state of cristamonads, from which other major forms evolved.

The role of host phylogeny varies in shaping microbial diversity in the hindguts of lower termites.

The hindguts of lower termites and Cryptocercus cockroaches are home to a distinct community of archaea, bacteria, and protists (primarily parabasalids and some oxymonads). Within a host species, the composition of these hindgut communities appears relatively stable, but the evolutionary and ecological factors structuring community composition and stability are poorly understood, as are differential impacts of these factors on protists, bacteria, and archaea. We analyzed the microbial composition of parabasalids and bacteria in the hindguts of Cryptocercus punctulatus and 23 species spanning 4 families of lower termites by pyrosequencing variable regions of the small-subunit rRNA gene. Especially for the parabasalids, these data revealed undiscovered taxa and provided a phylogenetic basis for a more accurate understanding of diversity, diversification, and community composition. The composition of the parabasalid communities was found to be strongly structured by the phylogeny of their hosts, indicating the importance of historical effects, although exceptions were also identified. Particularly, spirotrichonymphids and trichonymphids likely were transferred between host lineages. In contrast, host phylogeny was not sufficient to explain the majority of bacterial community composition, but the compositions of the Bacteroidetes, Elusimicrobia, Tenericutes, Spirochaetes, and Synergistes were structured by host phylogeny perhaps due to their symbiotic associations with protists. All together, historical effects probably resulting from vertical inheritance have had a prominent role in structuring the hindgut communities, especially of the parabasalids, but dispersal and environmental acquisition have played a larger role in community composition than previously expected.

The phylogenetic position of Kofoidia loriculata (Parabasalia) and its implications for the evolution of the Cristamonadea.

Kofoidia loriculata is a parabasalid symbiont inhabiting the hindgut of the lower termite Paraneotermes simplicicornis. It was initially described as a lophomonad due to its apical tuft of multiple flagella that disintegrate during cell division, but its phylogenetic relationships have not been investigated using molecular evidence. From single cell isolations, we sequenced the small subunit rRNA gene and determined that K. loriculata falls within the Cristamonadea, but is unrelated to other lophomonads. This analysis further demonstrates the polyphyly of the lophomonads and the necessity to re-assess the morphological and cellular evolution of the Cristamonadea.

Lophomonas blattarum and bronchopulmonary disease.

The natural habitat of the multiflagellate protozoon Lophomonas blattarum is as an endocommensal in the hindgut of insects such as cockroaches. However, it also causes bronchopulmonary disease in humans. The aim of this paper was to review the literature on this organism in the context of respiratory disease. The biology epidemiology, route of transmission, pathogenic mechanisms and diagnosis methods are also described. A total of 61 cases were identified in the literature. The majority of these reports were from China, with some cases from Peru and Spain. Most cases were adult males, although paediatric cases were reported in Peru. Clinical presentation was non-specific, including symptoms such as fever, cough and breathless. Antiprotozoal therapy was generally effective.

[A study on the differential diagnosis of ciliated epithelial cells from Lophomonas blattarum in bronchoalveolar lavage fluid].

OBJECTIVE: To validate the authenticity of the cases diagnosed as pulmonary Lophomonas blattarum infection in literatures and Lophomonas blattarum as a kind of pathogen resulting in pulmonary infection. METHODS: From June 2012 to May 2013, mobile cells with cilia at the anterior end of the cells were observed in BALF from 6 patients with pulmonary disease in our hospital. Morphological feature and ultrastructure of the cells were further investigated by optical microscope and electron microscope to determine the type of the cells referring to literature-published photos of Lophomonas blattarum. Literatures about Lophomonas blattarum infection were searched with keyword Lophomonas blattarum from Wanfang Data, China National Knowledge Infrastructure (CNKI) and PubMed. Diagnostic methods and figures provided by the literature were carefully reviewed, and the accuracy of diagnosis of pulmonary Lophomonas blattarum was identified. RESULTS: Mobile cells found in BALF from the 6 patients in our hospital had the morphological features of bronchial ciliate epithelial cells. A nucleus far from the cilia was observed in the middle or at the bottom of the cytoplasm, and these cells did not display the characteristic cytological structures of Lophomonas blattarum: calyx, perinuclear tubules and axial filament. Diagnosis of pulmonary Lophomonas blattarum reported in literatures so far were all based on the morphological features of mobile cells with a cluster of flagellate at anterior end of the cell by optical microscopy. None of the authors did further exploration on the ultrastructure of such a kind of cells and compared with features of Lophomonas blattarum described in the literature. All the active cells reported in literatures had the identical morphological features to those found in our investigation. CONCLUSION: In the past 20 years, all the diagnosed cases as pulmonary Lophomonas blattarum infection reported in our country were misdiagnosed. Currently, there is no evidence to show Lophomonas blattarum as a pathogen resulting in pulmonary infection.