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

Case series of complicated bronchopulmonary lophomoniasis. Differential diagnosis of tuberculosis?

Pulmonary lophomoniasis is a rare and life-threatening disease, most commonly reported across Asian and Latin American countries. Here, we have reported two cases of pulmonary lophomoniasis presenting with atypical manifestations. Case #1 represents a 19-year-old male patient with clinical characteristics suggestive of tuberculosis, presenting with hemoptysis and receiving antituberculosis treatment. Case #2 represents a 69-year-old man with post-tuberculosis pulmonary disease with cystic bronchiectasis presenting with polymicrobial co-infection. Based on our case experience, lophomoniasis should be considered in patients with pneumonia who do not respond to antibiotic treatment, and the corresponding epidemiological factors should be carefully considered in addition to bronchoscopy for precise diagnosis.

Characterization of Lophomonas spp. Infection in a Population of Critical Care Patients

Lophomonas are flagellated protozoa that have been increasingly associated with upper and lower airway infection in humans. The prevalence and characterization of this disease in the critically ill remains poorly understood. We present a series of eleven ICU patients with confirmed Lophomonas spp. identification in respiratory samples.

Geospatial Analysis and Molecular Epidemiologic Study of Emerging Pulmonary Lophomoniasis in Iran: A National Registry-Based Study

Introduction

Bronchopulmonary lophomoniasis (BPL) is a protozoan pulmonary disease that has been reported sporadically, but its incidence has been increasing. However, the epidemiology and risk factors of the disease have not been clearly identified. The current study aims to identify BPL cases molecularly and assess the demographic and some environmental factors for the first time on the prevalence of BPL as a national registry-based study in Iran. Methodology. The study tested 960 patients with lower respiratory tract symptoms whose bronchoalveolar lavage samples were submitted from seven provinces of Iran to the Iranian National Registry Center for Lophomoniasis. They were tested for BPL by a newly developed polymerase chain reaction test. The study assessed the association of Normalized difference vegetation index (NDVI), digital elevation model (DEM), and geographic latitude as environmental factors and sex and age as demographic factors on the prevalence of BPL. Geospatial information systems methods and chi-squared and Pearson's correlation tests were used for the assessment of geographical and environmental factor effects and statistical analysis, respectively.

Results

Of the 960 patients, 218 (22.7%) tested positive for BPL; the highest and lowest prevalence rates were reported from the south and northeast of Iran, respectively. The study found a correlation between geographic latitude and age with BPL prevalence, but no association was found for gender, NDVI, or DEM. Most patients were over 40 years old, and the rate of disease was higher in southern latitudes.

Conclusion

Age and geographical latitude were found to be risk factors for BPL. More exposure to dust and/or chronic pulmonary problems may explain the higher prevalence of the disease in older adults. Higher rates of BPL in lower latitudes may be due to warmer weather and longer days, which can confine individual activities indoors and result in more contact with domestic insects and infected dust.

Lophomonas blattarum-like organism in bronchoalveolar lavage from a pneumonia patient: current diagnostic scheme and polymerase chain reaction can lead to false-positive results

Lophomonas blattarum is an anaerobic protozoan living in the intestine of cockroaches and house dust mites, with ultramicroscopic characteristics such as the presence of a parabasal body, axial filament, and absence of mitochondria. More than 200 cases of Lophomonas infection of the respiratory tract have been reported worldwide. However, the current diagnosis of such infection depends only on light microscopic morphological findings from respiratory secretions. In this study, we attempted to provide more robust evidence of protozoal infection in an immunocompromised patient with atypical pneumonia, positive for Lophomonas-like protozoal cell forms. A direct search of bronchoalveolar lavage fluid via polymerase chain reaction (PCR), transmission electron microscopy (TEM), and metagenomic next-generation sequencing did not prove the presence of protozoal infection. PCR results were not validated with sufficient rigor, while de novo assembly and taxonomic classification results did not confirm the presence of an unidentified pathogen. The TEM results implied that such protozoal forms in light microscopy are actually non-detached ciliated epithelial cells. After ruling out infectious causes, the patient's final diagnosis was drug-induced pneumonitis. These findings underscore the lack of validation in the previously utilized diagnostic methods, and more evidence in the presence of L. blattarum is required to further prove its pathogenicity.

Effective Treatment of Chronic Cough with Tinidazole as the Newest Antiprotozoa against Lophomonas blattarum

Background

Chronic cough is a common problem in the setting of family physicians. Recently, Lophomonas blattarum was considered a cause of respiratory symptoms in children and adults.

Objective

This study is aimed at determining the effect of antiprotozoal treatment of Lophomonas in patients with a chronic cough in Mashhad during 2020-2021.

Materials and Methods

This study was a randomized clinical trial. In this study, 60 patients with chronic cough and unremarkable imaging findings, who were unresponsive to three steps of standard treatment, were randomly assigned to the treatment, with 2 weeks of tinidazole and placebo. The tinidazole and placebo were prepared in a completely identical shape, and a random assignment was performed by a third party. The primary outcome was a complete resolution of cough. A follow-up of treatment was performed. Data were analyzed using the SPSS software version 25.

Results

The basic demographic results showed no significant differences of sex and age between two groups. The results of this study showed a complete resolution of all respiratory symptoms in 40% (12), a complete improvement of cough in 40% (12), and a complete resolution of dyspnea in 50% (10) of the tinidazole group. The remaining showed significant improvement in the severity of cough and dyspnea. Postnasal drip, sputum, body temperature, and airway hyperresponsiveness were improved significantly. After tinidazole treatment, laboratory assessment of bronchial lavage and sputum revealed that 86 percent of smears were converted to negative.

Conclusion

Tinidazole effectively resolved the chronic cough and most of the respiratory symptoms. Lophomonas blattarum is a potential mechanism for chronic cough.

Detection of a Lophomonas, a rare pathogen in Bronchoalveolar lavage

Lophomonas infection is an emerging parasitic disease-causing respiratory infection. Although common in immunocompromised patient, it has been observed also in some immunocompetent cases. We report the case of a 45-year-old male who presented with productive cough, fever, and chest pain, with marked eosinophilia and cavitary lesion in the X-ray chest. KOH preparation and acid-fast bacilli microscopy of bronchoalveolar lavage (BAL) were negative. Direct microscopic examination of BAL accidentally showed a large number of living Lophomonas species with the movement of flagella. Methylene blue and Giemsa staining showed the plume of flagella and the nucleus. The patient was managed conservatively with metronidazole and get cured. It was concluded that the patient presented with signs and symptoms of pneumonia must be evaluated for rare events also if the patient was not responding with typical management of pneumonia. We reported the first case of this rare entity in Chhattisgarh state in an immunocompetent young Indian male.

Global Status of Emerging Lophomonas Infection: A Systematic Review of Reported Cases (1993—2020)

Purpose. Lophomonas spp., is an emerging protozoan parasite that belongs to the Parabasalids (Parabasalia, lophomonadida) which infects the respiratory tracts of humans. Despite the presence of a few reports of human lophomoniasis, the true burden of Lophomonas infection is unknown. This systematic review aimed to elucidate the latest global status of publications reporting human cases of lophomoniasis as a new emerging protozoal disease. Methods. A comprehensive and systematic search was performed in 10 (five English and five Persian) databases for studies reporting cases of lophomoniasis between 1993 and March 2020 (27 years). Then, the selected articles were carefully reviewed and screened based on the inclusion and exclusion criteria. Results. Overall, 32 eligible publications reporting 307 lophomoniasis cases from around the world are included in this review. The patients were aged between 1 month and 84 (mean age = 23.7 years). The highest number of cases (n = 171; 55.7%, $P<0.04$ ) significantly belonged to the juvenile age group (aged ≤18 years). The male to female ratio of the cases was almost equal, and no statistically significant difference between them was observed. The maximum number of cases (n = 237) was reported from Iran. Most cases (n = 196; 63.85%) had no history of underlying diseases/organ transplantation $\left(P<0.001\right)$ . Moreover, the BAL specimen was the most commonly used clinical sample to diagnose lophomoniasis $\left(P<0.001\right)$ . Conclusion. Our findings reveal that the prevalence of lophomoniasis is likely to be markedly underestimated when evaluated based on published case reports. Additionally, our data, at least for the time being, supports the idea that Lophomonas spp. should not be considered as an opportunistic infection. Thus, current work sheds light on some controversial issues regarding the epidemiological aspects of lophomoniasis.

Molecular evidence of upper and lower respiratory infection due to Lophomonas in a post‐kidney transplantation patient

We report a case of lophomoniasis in a kidney post‐transplantation patient. The patient, 46‐year‐old man, had pneumonia, acute sinusitis, and tonsillitis on admission. We recommend that lophomoniasis should be essentially ruled out in all patients suffering from post‐transplantation infection, particularly in those who do not respond to routine antibiotic regimens.

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.

First report of Lophomonas spp. in German cockroaches (Blattella germanica) trapped in hospitals, northern Iran

Cockroaches are considered to be important reservoirs for protozoan and helminth parasites,particularly an emerging Lophomonas spp., protozoan parasite. German cockroaches, Blattella germanica (B. germanica), are domestic pest distributed worldwide. However, little information is available regarding the burden of Lophomonas spp. infestation among domestic cockroach population worldwide. The present study investigated parasitic agents, emphasizing Lophomonas spp. infestation among B. germanica in northern Iran. During spring and summer 2018, a total of 496 adults B. germanica (265 males and 231 females) were trapped by hand and glass traps from the teaching hospitals in Mazandaran, Sari, northern Iran. All cockroaches were identified using taxonomic keys. Each cockroaches was anesthetized with chloroform and the alimentary tract removed. Each section was smeared onto a glass slide. All the smears were examined under light microscopy to determine the presence of the parasites. Ten genera of parasites were identified from the trapped B. germanica; overall, 233 (47%) were found to be positive for helminths (n = 135) and protozoa (n = 98). The helminths included Aspiculuris tetraptera egg (67/233, 28.7%), Oxiuros sp. (39/233; 16.7%), Dentostomella translucida (17/233; 7.3%), and nematodes Ova (12/233; 5.2%). The protozoan parasites identified Gregarina sp. (61/233; 26.2%), Entamoeba sp. (19/233; 8.2%), Blastocystis sp. (5/233; 2.1%), Lophomonas (4/233; 1.7%), Nyctotherus sp. (4/233; 1.7%), unclassified flagella (5/233; 2.1%). Lophomonas spp. was detected within the gut of B. germanica, for the first time, in Iran. It has previously been identified in the gut of cockroaches a long time ago, however, this is the first attempt to detect Lophomonas in cockroaches housing in hospitals. Thereby, it possibly presenting pose a serious respiratory infection risk for patients and health care personnel.

ClpV1 in avian pathogenic Escherichia coli is a crucial virulence factor contributing to meningitis in a mouse model in vivo

Meningitis associated with avian pathogenic Escherichia coli (APEC) is an infectious disease of poultry that has gained significant attention because of its potential to infect humans. APEC can utilize two type Ⅵ secretion systems (T6SSs) to efficiently transport toxin effectors into hosts. ClpV1 is one of the core components of the T6SS1. To our knowledge, it has not been clarified how the clpV1 gene contributes to the pathogenicity of meningitis-associated APEC. To investigate the function of the clpV1 gene in the process of Escherichia coli meningitis, a mutant TW-XMΔclpV1 strain was constructed and characterized. In this study, the clpV1 deleted strain displayed a significant decrease in both motility and biofilm formation as well as a reduction in the expression of virulence genes fliC, luxS and ibeA. In vivo studies using mouse and duck models found that the clpV1 deleted groups showed decreased proliferation, fewer lesions and lower expression of inflammatory cytokines in the brain suggesting that clpV1 is involved in the pathogenicity of TWXM. Besides, the decreased quantity of Evans Blue (EB) and the down-regulation of tight junctions (TJs) proteins in the mouse clpV1 deleted group demonstrating a more intact blood-brain barrier (BBB). In conclusion, these results suggest that the clpV1 gene is associated with motility and biofilm formation of TWXM strain and contributes to meningitis by damaging the BBB and brain tissues.

Some undesirable traps which can mislead the pathologist

In clinical laboratories, the diagnosis of parasite diseases can sometimes be challenging for non-expert microbiologists. Indeed, in spite of the advent of the molecular biology, macroscopic and microscopic examinations still remain essential. Nonetheless, it is usually not automated and requires great skills to complete the correct diagnosis. It is not infrequent that inert elements mislead to erroneous diagnoses. Through three different concrete examples, this article aims at underscoring the actual risk of parasite misidentification and at highlighting the systematic approach to be conducted in order to enable reliable diagnosis.

Lophomonas isolation in sputum sample at Peru

Lophomonas infection is an emerging parasitic disease causing respiratory infections. After China, Peru is the second country with the highest number of cases. In the bright-field microscopy evaluation of fresh samples, most of them are incorrectly estimated. Therefore, correct identification using cytological stains is to be supplemented. We report a case of a 29-year-old male with typical clinical symptoms of pneumonia, marked eosinophilia, and noninfiltrative pattern in chest X-ray, who had bronchopulmonary lophomoniasis.

Bronchopulmonary lophomoniasis: A rare cause of pneumonia in an immunosuppressed host

Bronchopulmonary lophomoniasis is rare but immunocompromised individual is susceptible to this infection. We reported a case of bronchopulmonary lophomoniasis in a Malaysian female with systemic lupus erythromatosus. She presented with productive cough, shortness of breath and high-grade fever for 2 weeks. Physical examination revealed bronchial sound and crackles over the left lung with, reduced expansion and dull percussion in lower left lobe. Chest radiography showed consolidation of the left lung. Routine laboratory tests revealed general low cell count. Blood and sputum culture were negative. Bronchoalveolar lavage stain and culture for bacterial and fungal were negative. Bronchoalveolar lavage for Lophomonas blattarum was positive. Patient was treated with antiprotozoal drug, metronidazole. All her clinical problems resolved and she was discharged 14 days after admission.

First Molecular Diagnosis of Lophomoniasis: the End of a Controversial Story

INTRODUCTION

We report a case of lophomoniasis in an immunocompetent patient with acute paranasal sinusitis from the north of Iran whose disease was diagnosed by both microscopic and molecular methods.

CASE PRESENTATION

The patient, a 40-year-old woman, suffered from upper respiratory infection, was referred to the Iranian National Registry Center for Lophomoniasis (INRCL) at the Mazandaran University of Medical Sciences, Sari, Iran, for diagnosis. A direct wet mount of nasal discharge revealed the flagellate protozoa morphologically identified Lophomonas blattarum. Moreover, through a specific polymerase chain reaction (PCR) of nasal discharge, a 214-bp band was observed, confirming the genus Lophomonas spp. The patient was treated successfully with metronidazole 500 mg t.i.d for 1 week.

CONCLUSION

To the best of our knowledge, this is the first molecular detection of lophomoniasis in the literature. According to our preliminary study, a reliable PCR test is available now for detecting the Lophomonas parasite.

Bronchopulmonary infection by Lophomonas blattarum in a pediatric patient after hematopoietic progenitor cell transplantation: first report in Mexico

Lophomonas blattarum is a multiflagellated protozoon which parasitizes the gut of termites and cockroaches. Although L. blattarum infection is rare, it can affect lung, maxillary sinuses and genitourinary tract. The presentation of bronchopulmonary lophomonas includes nonspecific symptoms such as fever, cough and dyspnea. Diagnosis is based on identification of living protozoan forms in fresh samples from respiratory secretions (bronchoalveolar lavage). We report the case of a 2-year-old male with a history of severe combined immunodeficiency (T-, B-, NK-), post-hematopoietic stem cell transplant and full immune reconstitution 12 months following a successful transplant who thereafter presented lophomonas.