Organ-specific Toxocara canis larvae migration and host immune response in experimentally infected mice.

We investigated organ specific Toxocara canis larval migration in mice infected with T. canis larvae. We observed the worm burden and systemic immune responses. Three groups of BALB/c mice (n=5 each) were orally administered 1,000 T. canis 2nd stage larvae to induce larva migrans. Mice were sacrificed at 1, 3, and 5 weeks post-infection. Liver, lung, brain, and eye tissues were collected. Tissue from 2 mice per group was digested for larval count, while the remaining 3 mice underwent histological analysis. Blood hematology and serology were evaluated and compared to that in a control uninfected group (n=5) to assess the immune response. Cytokine levels in bronchoalveolar lavage (BAL) fluid were also analyzed. We found that, 1 week post-infection, the mean parasite load in the liver (72±7.1), brain (31±4.2), lungs (20±5.7), and eyes (2±0) peaked and stayed constant until the 3 weeks. By 5-week post-infection, the worm burden in the liver and lungs significantly decreased to 10±4.2 and 9±5.7, respectively, while they remained relatively stable in the brain and eyes (18±4.2 and 1±0, respectively). Interestingly, ocular larvae resided in all retinal layers, without notable inflammation in outer retina. Mice infected with T. canis exhibited elevated levels of neutrophils, monocytes, eosinophils, and immunoglobulin E. At 5 weeks post-infection, interleukin (IL)-5 and IL-13 levels were elevated in BAL fluid. Whereas IL-4, IL-10, IL-17, and interferon-γ levels in BAL fluid were similar to that in controls. Our findings demonstrate that a small portion of T. canis larvae migrate to the eyes and brain within the first week of infection. Minimal tissue inflammation was observed, probably due to increase of anti-inflammatory cytokines. This study contributes to our understanding of the histological and immunological responses to T. canis infection in mice, which may have implications to further understand human toxocariasis.

Detection of trichomonads in patients with lung cancer and transcription analysis on the response of human pulmonary epithelial cells to Trichomonas tenax invasion.

INTRODUCTION: Lung cancer is one of the most prevalent malignancies worldwide. Substantial research has illuminated the intricate interplay between microorganisms and human health, revealing their role in disease regulation. Trichomonads is a flagellated protozoan in the human cavity and have been previously identified as a pathogen associated with pneumonia, contributing to tissue chronic inflammation and carcinogenesis. METHODS: Nested polymerase chain reaction methods were employed to scrutinize the prevalence of trichomonads in the bronchovesicular fluid of patients diagnosed with lung cancer. Subsequently, the influence of Trichomonas tenax invasion on lung cancer cells was elucidated through proliferation assays, migration assays, and transcription analysis. RESULTS: Bronchoalveolar fluid samples from lung cancer patients yielded positive nested PCR results for eight out of twenty-seven samples. Seven of these samples were identified as Trichomonas tenax, while one was identified as Tetratrichomonas spp. Our findings revealed a significant upregulation of pathways associated with carcinogenesis, including cellular proliferation, migration, and drug resistance, in response to T. tenax invasion. CONCLUSIONS: This study underscores the importance of recognizing the presence of trichomonads and the influence of T. tenax invasion on host responses to respiratory diseases. The identified pathways implicated in cancer development may pave the way for developing targeted treatment strategies for pulmonary diseases. These findings hold promise for informing and improving the precision of therapeutic interventions in the context of pulmonary ailments.

Parasitic larvae in bronchoalveolar lavage fluid in a non-immunocompromised patient.

Strongyloides stercoralis is responsible for a significant human parasitic infection known as strongyloidiasis. In addition, pulmonary strongyloidiasis is one of the most critical signs of disseminated strongyloidiasis. In this instance, S. stercoralis was unexpectedly discovered in bronchoalveolar lavage fluid.

Subcutaneous ivermectin for the treatment of the hyperinfection syndrome by Strongyloides stercoralis / [Ivermectina subcutánea en el tratamiento de un síndrome de hiperinfección por Strongyloides stercoralis].

Strongyloidiasis is a disease caused by the nematode Strongyloides stercoralis that is endemic in rural regions in tropical and subtropical countries. Immunosuppressed patients have an increased risk of infection by this parasite and are at risk of developing a hyperinfection syndrome which involves a higher risk of death. The syndrome is treated with ivermectin, however, there is no parenteral presentation of this medication for human use in Colombia or the world, which is an important problem in patients who have compromised enteral absorption, for instance, those with intestinal obstructions. We present a case of hyperinfection syndrome by Strongyloides stercoralis in Colombia, which was treated with subcutaneous ivermectin. Our purpose is to encourage pharmacokinetic and pharmacodynamic studies to establish this route of administration in the future as an alternative for those patients who have a high risk of therapeutic failure with the oral route.

La estrongiloidiasis es una enfermedad causada por el nematodo Strongyloides stercoralis, endémico en las regiones rurales de los países tropicales y subtropicales. Los pacientes inmunosuprimidos tienen un mayor riesgo de infección con este parásito y pueden terminar desarrollando un síndrome de hiperinfección que conlleva un alto riesgo de muerte. En el tratamiento se utiliza la ivermectina, pero, ni en Colombia ni en el mundo, existe una presentación parenteral del medicamento para uso en humanos, lo cual es un problema en aquellos pacientes que puedan tener comprometida la absorción intestinal, como es el caso de aquellos con obstrucciones intestinales. Se reporta el caso de un síndrome de hiperinfección por S. stercoralis en Colombia tratado con ivermectina subcutánea; la idea al presentarlo es incentivar los estudios de farmacocinética y farmacodinamia que analicen esta vía de administración como alternativa para el tratamiento de pacientes con riesgo de fracaso terapéutico con la vía oral.

Persistent Legionnaires' Disease and Associated Antibiotic Treatment Engender a Highly Disturbed Pulmonary Microbiome Enriched in Opportunistic Microorganisms.

Despite the importance of pneumonia to public health, little is known about the composition of the lung microbiome during infectious diseases, such as pneumonia, and how it evolves during antibiotic therapy. To study the possible relation of the pulmonary microbiome to the severity and outcome of this respiratory disease, we analyzed the dynamics of the pathogen and the human lung microbiome during persistent infections caused by the bacterium Legionella pneumophila and their evolution during antimicrobial treatment. We collected 10 bronchoalveolar lavage fluid samples from three patients during long-term hospitalization due to pneumonia and performed a unique longitudinal study of the interkingdom microbiome, analyzing the samples for presence of bacteria, archaea, fungi, and protozoa by high-throughput Illumina sequencing of marker genes. The lung microbiome of the patients was characterized by a strong predominance of the pathogen, a low diversity of the bacterial fraction, and an increased presence of opportunistic microorganisms. The fungal fraction was more stable than the bacterial fraction. During long-term treatment, no genomic changes or antibiotic resistance-associated mutations that could explain the persistent infection occurred, according to whole-genome sequencing analyses of the pathogen. After antibiotic treatment, the microbiome did not recover rapidly but was mainly constituted of antibiotic-resistant species and enriched in bacteria, archaea, fungi, or protozoa associated with pathogenicity. The lung microbiome seems to contribute to nonresolving Legionella pneumonia, as it is strongly disturbed during infection and enriched in opportunistic and/or antibiotic-resistant bacteria and microorganisms, including fungi, archaea, and protozoa that are often associated with infections.IMPORTANCE The composition and dynamics of the lung microbiome during pneumonia are not known, although the lung microbiome might influence the severity and outcome of this infectious disease, similar to what was shown for the microbiome at other body sites. Here we report the findings of a comprehensive analysis of the lung microbiome composition of three patients with long-term pneumonia due to L. pneumophila and its evolution during antibiotic treatment. This work adds to our understanding of how the microbiome changes during disease and antibiotic treatment and points to microorganisms and their interactions that might be beneficial. In addition to bacteria and fungi, our analyses included archaea and eukaryotes (protozoa), showing that both are present in the pulmonary microbiota and that they might also play a role in the response to the microbiome disturbance.

Leishmania donovani and Pneumocystis jirovecii (carinii) diagnosed on bronchoalveolar lavage cytology in a liver transplant recipient with Cytomegalovirus infection.

Liver transplant recipients are prone to several infections, including lung infections, which can lead to substantial morbidity and mortality. Bronchoalveolar lavage (BAL) cytology is a rapid and sensitive diagnostic tool to identify the etiologic agents. We report a rare case of a 24-year-old male, post Live donor liver transplantation for autoimmune chronic liver disease, who presented with cough, fever, weight loss, and cavitatory lesion in lung. BAL cytology revealed Leishmania donovani (LD) and Pneumocystis jirovecii/carinii (PCP). Cytomegalovirus deoxyribonucleic acid polymerase chain reaction (CMV DNA PCR) test showed markedly raised levels. Patient was put on treatment for these multiple infections and showed significant improvement. Thus, rapid diagnosis of infections through BAL cytology is crucial in transplant recipients to institute timely therapy and avoid undesirable empirical treatments. Moreover, this case highlights a rare finding of LD bodies along with PCP in BAL cytology.

First molecular identification of Aelurostrongylus abstrusus in a cat presenting severe respiratory disease from Israel.

Feline lung worm infection is increasingly reported in recent years, and recognized as a cause for respiratory disease in cats. Aelurostrongylus abstrusus is regarded as the most prevalent cause of such cases. Infective L3 larvae carried in gastropods and paratenic hosts infect felines, developing to adult worms that reside in the lungs' parenchyma and may cause verminous pneumonia. The L1 larvae hatch from eggs deposited in the lung, and are released to the environment by either feces or sputum. While the majority of epidemiological information regarding A. abstrusus originates in European countries, recent studies have shown that it is also found around the Mediterranean basin, as far east as Turkey and Cyprus. A local domestic cat from Israel showing signs of respiratory illness was diagnosed with aelurostrongylosis, confirmed by both morphological and molecular tools. Presence in Israel of this nematode was previously reported in 1949, with no further mentions since. ITS-2 sequence of the isolated larvae was highly similar to that of A. abstrusus from domestic cats from Italy. These findings show that distribution of A. abstrusus stretch to the eastern shores of the Mediterranean, and that this nematode should be considered as a cause for respiratory disease in cats in Israel and the surrounding countries.

Comparison of Loop-Mediated Isothermal Amplification and Real-Time PCR Assays for Detection of Strongyloides Larvae in Different Specimen Matrices.

Strongyloides stercoralis can cause disease that ranges from asymptomatic chronic infection to fatal hyperinfection. Diagnosis from stool can be challenging because the most sensitive conventional tests require live larvae to be effective and there can be low larval output in chronic infection. Nucleic acid amplification tests (NAAT) have been developed to complement existing diagnostic methods. We compared a recently developed loop-mediated isothermal amplification (LAMP) assay with a real-time PCR that has previously been validated with larval microscopy. The limits of detection-quantified using serial dilutions of DNA extracts from single Strongyloides ratti third-stage (L3) larvae spiked into approximately 250 µl of 5 different S. stercoralis-negative stool specimens-were 10-3 (1/5 replicates) and 10-2 (1/5 replicates) dilutions for PCR and LAMP, respectively. PCR was positive for 4/5 replicates at 10-2 LAMP was compared to PCR using extracts from 396 stool specimens collected in Bangladesh and Australia, of which 53 were positive and 343 were negative by PCR. The positive percentage agreement of LAMP was 77.3% (95% score confidence interval [CI], 64.5 to 86.6). The negative percentage agreement was 100% (95% CI, 98.9 to 100). In a preliminary investigation, PCR and LAMP assays were positive using DNA extracted from serum (PCR, 3/16 extracts; LAMP, 2/16 extracts) and bronchoalveolar lavage fluid (PCR and LAMP, 2/2 extracts), demonstrating proof of concept. Compared to PCR, the lower number of positive results using the LAMP assay may have been due to reaction inhibitors and DNA degradation, and strategies to improve the LAMP assay are discussed.

House dust mite drives proinflammatory eicosanoid reprogramming and macrophage effector functions.

BACKGROUND: Eicosanoid lipid mediators play key roles in type 2 immune responses, for example in allergy and asthma. Macrophages represent major producers of eicosanoids and they are key effector cells of type 2 immunity. We aimed to comprehensively track eicosanoid profiles during type 2 immune responses to house dust mite (HDM) or helminth infection and to identify mechanisms and functions of eicosanoid reprogramming in human macrophages. METHODS: We established an LC-MS/MS workflow for the quantification of 52 oxylipins to analyze mediator profiles in human monocyte-derived macrophages (MDM) stimulated with HDM and during allergic airway inflammation (AAI) or nematode infection in mice. Expression of eicosanoid enzymes was studied by qPCR and western blot and cytokine production was assessed by multiplex assays. RESULTS: Short (24 h) exposure of alveolar-like MDM (aMDM) to HDM suppressed 5-LOX expression and product formation, while triggering prostanoid (thromboxane and prostaglandin D2 and E2 ) production. This eicosanoid reprogramming was p38-dependent, but dectin-2-independent. HDM also induced proinflammatory cytokine production, but reduced granulocyte recruitment by aMDM. In contrast, high levels of cysteinyl leukotrienes (cysLTs) and 12-/15-LOX metabolites were produced in the airways during AAI or nematode infection in mice. CONCLUSION: Our findings show that a short exposure to allergens as well as ongoing type 2 immune responses are characterized by a fundamental reprogramming of the lipid mediator metabolism with macrophages representing particularly plastic responder cells. Targeting mediator reprogramming in airway macrophages may represent a viable approach to prevent pathogenic lipid mediator profiles in allergy or asthma.

A case report of pulmonary tritrichomonosis in a pig.

BACKGROUND: Tritrichomonads like porcine Tritrichomonas foetus (previously named Tritrichomonas suis), can commensally live in nasal cavity of pigs, but it is rare to cause pulmonary tritrichomonosis. CASE PRESENTATION: A 40-day-old piglet was presented for persistent labor breathing and diagnosed with parasite infections in the lung by analysis of bronchoalveolar lavage (BAL) under microscope. By taking advantage of next-generation sequencing approach, we found 9611 homologous tags belonging to 50 annotated genes of tritrichomonads by analysis of mRNA of the bronchoalveolar lavage with the parasite infection. Furthermore, RT-PCR and DNA sequencing analysis confirmed the presence of the tritrichomonad. FINDINGS: Here, we report a case of pulmonary tritrichomonosis in a pig. By taking advantage of next-generation sequencing approach, we found 9611 homologous tags belonging to 50 annotated genes of tritrichomonads by analysis of mRNA of the bronchoalveolar lavage with the parasite infections. Furthermore, RT-PCR and DNA sequencing analysis confirmed the presence of the tritrichomonad. CONCLUSION: Our results demonstrate that tritrichomonads like porcine Tritrichomonas foetus can cause lung infections of pigs and reveal that next-generation sequencing is potential to identify rare diseases like pulmonary tritrichomonosis in clinical.

Real-Time Polymerase Chain Reaction Assay on Bronchoalveolar Lavage: An Alternative Method for Diagnosing Chronic Pulmonary Schistosomiasis?

Schistosomiasis causes mainly hepatic and genitourinary damage. Although lung nodules have been commonly described in acute phase, they are presumably underdiagnosed in chronic schistosomiasis. We previously reported a series of patients with chronic pulmonary schistosomiasis confirmed by the histological examination of the lung biopsies. In the present work, we retrospectively tested an in-house real-time polymerase chain reaction for Schistosoma (currently validated for diagnosis on stool and on urine) in the bronchoalveolar lavage (BAL) of a couple of those patients, and both resulted positive. The possibility of testing BAL with molecular methods targeting a wide spectrum of pathogens, including parasites, is appealing. Further studies are needed to validate this technique that might reduce unnecessary biopsies.

A case of Strongyloides hyperinfection syndrome in the setting of persistent eosinophilia but negative serology.

Strongyloides stercoralis is a unique intestinal nematode with the ability to replicate and complete its life cycle without leaving the host. We report a fatal case of Strongyloides hyperinfection syndrome in a patient who had persistent eosinophilia for several years but negative Strongyloides serology. Our case suggests that ELISA serologies cannot solely be relied upon to diagnose Strongyloides stercoralis infection; history and clinical judgment remain crucial to this diagnosis.

Bronchopulmonary Disease Caused by Flagellated Protozoa Infection in 15 Chinese Children.

BACKGROUND: Bronchopulmonary disease caused by flagellated protozoa infection (BPFP) is thought to be rare in children but may be an emerging or underestimated disease, especially in developing countries. METHODS: In this study, we retrospectively reviewed records of 15 patients who were presented with a cough, wheezing or bronchopulmonary disease of unknown causes during admission, and patients who were finally diagnosed with BPFP from January 2014 to January 2015 were enrolled. Protozoa were observed in bronchoalveolar lavage fluid by light microscopy. RESULTS: A total of 15 pediatric cases (11 male and 4 female individuals, from 1 year 8 months to 12 years 1 month of age) with flagellated protozoa infection diagnosed by light microscopy were recruited. The course of the disease at the time of diagnosis was from 10 days to 11 months. Patients presented with a fever (N = 9), cough (N = 11), wheezing (N = 5) and chest pain (N = 5). Laboratory data showed elevated peripheral blood leucocytes (N = 6), eosinophilic granulocytes (N = 3), C-reactive protein (N = 5) and immunoglobulin E (N = 3). Bronchoscopy revealed a mucus plug (N = 3) and bronchiectasis (N = 1). Lung computed tomography results indicated ground-glass opacification (N = 2), atelectasis (N = 3), bronchiectasis (N = 1), bronchial wall thickening (N = 3) or nodular opacity (N = 6, including 1 case of pulmonary embolism). All children responded to metronidazole for a 2- to 5-week treatment period. CONCLUSIONS: Patients with BPFP often have a chronic or recurrent course and present with recurrent fever, cough, wheezing and chest pain. Chest imaging may reveal ground-glass opacification, atelectasis, bronchiectasis or nodular opacity (including pulmonary embolism). BPFP responds favorably to metronidazole treatment.