Chlamydia psittaci detected at a live poultry wholesale market in central China.

BACKGROUND: We investigated the presence of Chlamydia psittaci in poultry and the environment in live poultry wholesale markets in Changsha during 2021-2022 and conducted a phylogenetic analysis to understand its distribution in this market. METHODS: In total, 483 samples were analyzed using real-time polymerase chain reaction and 17 C. psittaci-positive samples using high-throughput sequencing, BLAST similarity, and phylogenetic analysis. RESULTS: Twenty-two out of 483 poultry and environmental samples were positive for C. psittaci (overall positivity rate: 4.55%) with no difference in positivity rates over 12 months. Chlamydia psittaci was detected at 11 sampling points (overall positivity rate: 27.5%), including chicken, duck, and pigeon/chicken/duck/goose shops, with pigeon shops having the highest positivity rate (46.67%). The highest positivity rates were found in sewage (12.5%), poultry fecal (7.43%), cage swab (6.59%), avian pharyngeal/cloacal swab (3.33%), and air (2.29%) samples. The ompA sequences were identified in two strains of C. psittaci, which were determined to bear genotype B using phylogenetic analysis. Thus, during monitoring, C. psittaci genotype B was detected in the poultry and environmental samples from the poultry wholesale market in Changsha. CONCLUSIONS: To address the potential zoonotic threat, C. psittaci monitoring programs in live poultry markets should be enhanced.

Reactive Oxygen Species Modulate Th17/Treg Balance in Chlamydia psittaci Pneumonia via NLRP3/IL-1ß/Caspase-1 Pathway Differentiation.

Chlamydia psittaci pneumonia (CPP) is a lung disease caused by the infection with the Chla-mydia psittaci bacterium, which can lead to severe acute respiratory distress syndrome and systemic symptoms. This study explored the specific mechanisms underlying the impact of reactive oxygen species (ROS) on the Th17/Treg balance in CPP. The levels of ROS and the differentiation ratio of Th17/Treg in the peripheral blood of healthy individuals and CPP patients were measured using ELISA and flow cytometry, respectively. The association between the ROS levels and Th17/Treg was assessed using Pearson correlation analysis. The ROS levels and the Th17/Treg ratio were measured in CD4+ T cells following H2O2 treatment and NLRP3 inhibition. The effects of H2O2 treatment and NLRP3 inhibition on the NLRP3/IL-1ß/caspase-1 pathway were observed using immunoblotting. Compared to the healthy group, the CPP group exhibited increased levels of ROS in the peripheral blood, an elevated ratio of Th17 differentiation, and a decreased ratio of Treg differentiation. ROS levels were positively correlated with the Th17 cell proportion but negatively correlated with the Treg cell proportion. The ROS levels and NLRP3/IL-1ß/caspase-1 expression were up-regulated in CD4+ T cells after H2O2 treatment. Furthermore, there was an increase in Th17 differentiation and a decrease in Treg differentiation. Conversely, the NLRP3/IL-1ß/caspase-1 pathway inhibition reversed the effects of H2O2 treatment, with no significant change in the ROS levels. ROS regulates the Th17/Treg balance in CPP, possibly through the NLRP3/IL-1ß/caspase-1 pathway. This study provides a new perspective on the development of immunotherapy for CPP.

Chlamydia psittaci Pneumonia: Diagnosis, Treatment, and Challenges in the Context of COVID-19.

BACKGROUND Rapid diagnosis is critical for effective treatment of severe pneumonia during the COVID-19 pandemic. Chlamydia psittaci, an atypical community-acquired pathogen, typically exhibits nonspecific clinical signs and requires stringent conditions for microbiological culture, complicating its identification. Metagenomic next-generation sequencing (mNGS), which involves shotgun sequencing of DNA or RNA from clinical samples, is a key technology in clinical settings. Although mNGS technology identifies nucleic acids, it should not be directly equated with the presence of pathogenic microorganisms. Nonetheless, it shows promise as a principal method for detecting atypical pathogens in severe infectious diseases in the future. CASE REPORT We present a case of severe community-acquired Chlamydia psittaci pneumonia, highlighting the ongoing mutations and frequent spread of COVID-19. The patient's severe pulmonary infection rapidly advanced, resulting in multiple organ failure, necessitating extracorporeal membrane oxygenation (ECMO) support. Despite initial inconclusive routine laboratory tests, diagnosis of Chlamydia psittaci pneumonia was confirmed through mNGS. Antibiotic treatment and multi-organ functional support were administered, leading to the patient's successful recovery and hospital discharge. CONCLUSIONS Diagnosing severe pneumonia caused by atypical pathogens amid the COVID-19 pandemic presents significant challenges. Initiating ECMO support without effective infection control poses considerable risks, such as increasing risk of catheter-related infections and antimicrobial treatment failure. In the case presented, mNGS proved instrumental in screening for atypical pathogens in critical infectious diseases. Application of multi-organ function support in reversible conditions affords clinicians time for pathogen identification and treatment, offering novel approaches for diagnosing and treating severe pneumonia induced by unconventional pathogens during epidemic outbreaks.

Chlamydia psittaci-related pleuro-myocarditis.

Chlamydia psittaci ‒ related community-acquired pneumonia associated to acute myocarditis was diagnosed in a young man with no medical history, and a professional exposition to birds. The diagnosis was confirmed with positive specific polymerase chain reaction in bronchoalveolar lavage. The patient was treated with spiramycin for two weeks with anti-inflammatory treatment for myocarditis for three months. Clinical and biological improvement was rapidly observed followed by normalization of electrocardiogram and chest CT scan. No relapse was reported for over a two-year follow-up.

Chlamydia psittaci Screening of Animal Workers from Argentina Exposed to Carrier Birds.

Different syndromes are involved in human psittacosis (flu-like syndrome, atypical pneumonia up to lacrimal gland lymphoma). Diagnostic methods include serology, culture, and PCR. The rate of Chlamydia psittaci (Cp) positive tests among exposed workers is still unknown. Our study aimed to assess the rate of positive tests among workers who have contact with carrier birds in natural reserves from Buenos Aires, Argentina. Secondary aims were to analyze risk factors linked to these outcomes and the occurrence of signs that suggest psittacosis. Nasopharyngeal swabs and serum pairs were collected from employees who had interacted with confirmed carrier birds. Those with detectable DNA of Cp and/or anti-Chlamydia spp. antibody baseline titer ≥ 160 mUI/ml, or at least quadruplicating, were considered positive. Activities performed with or near birds, personal protective equipment use, and previous chronic conditions were assessed. Possible Cp-related pathologies were evaluated during follow-up. A total of 63 exposed workers (71.4% men) with a median age of 35.7 years (IQR 26-39) were evaluated to detect 28.6% positives. Respiratory chronic conditions were the unique factor associated with positive tests (OR 5.2 [1.5-18.5] p < .05). Surprisingly, about a third of the workers resulted positive and all responded to medical treatment, none developing an acute atypical pneumonia syndrome associated with classical presentation of psittacosis. Active testing for early diagnosis and proper treatment in zoological workers exposed to carrier or potentially carrier birds is strongly suggested as part of zoonotic diseases preventive measures.

Evaluation of clinical characteristics and risk factors associated with Chlamydia psittaci infection based on metagenomic next-generation sequencing.

INTRODUCTION: Psittacosis is a zoonosis caused by Chlamydia psittaci, the clinical manifestations of Psittacosis range from mild illness to fulminant severe pneumonia with multiple organ failure. This study aimed to evaluate the clinical characteristics of Chlamydia psittaci infection diagnosed based on metagenomic next-generation sequencing(mNGS), as well as the risk factors affecting the progress of Chlamydia psittaci infection, in order to improve the effect of therapeutics. METHODS: We retrospectively analyzed the clinical data of patients infected with chlamydia psittaci in the First Affiliated Hospital of Nanchang University from January 2021 to December 2021. The patient's past medical history, clinical manifestations, laboratory examinations, chest CT results, treatment status, and prognosis data were collected. we also investigated both the pathogenic profile characteristics and the lower respiratory tract microbiota of patients with Chlamydia psittaci pneumonia using mNGS. RESULTS: All cases of Chlamydia psittaci in our research have been confirmed by mNGS. Among 46 cases of Chlamydia psittaci pneumonia, Poultry exposure was reported in 35 cases. In severe cases of Chlamydia psittaci pneumonia, Neutrophils, Procalcitonin (PCT), Lactate Dehydrogenase (LDH), Hydroxybutyrate Dehydrogenase (HBDH), Creatine Kinase Isoenzymes-B (CK-MB) and D-Dimer levels were remarkably higher than that of non-severe cases, except for lymphocytes (all P < 0.05). Chest CT scans showed Bilateral (77.8%), multiple lobar lungs (85.2%), pleural effusions (44.4%) involvement in those suffering from severe Chlamydia psittaci pneumonia, whereas its incidence was 0%, 21.1% and 10.5% in non-severe patients, respectively (P < 0.05). Multivariate analysis revealed that higher lymphocyte concentrations (OR 0.836, 95% CI 0.714-0.962, P = 0.041) were the only protective factor for survival. mNGS results indicated that 41.3% of patients (19/46) had suspected coinfections with a coinfection rate of 84.2% (16/19) in the severe group, much higher than that in the non severe group (p < 0.05). No significantly different profiles of lower respiratory tract microbiota diversity were found between non severe group and severe group. CONCLUSION: A history of poultry exposure in patients can serve as an important basis for diagnosing Chlamydia psittaci pneumonia, and patients with severe Chlamydia psittaci pneumonia are more likely to develop elevated inflammatory biomarkers as well as elevated cardiac markers. Higher lymphocyte concentrations are protective factors associated with severe C. psittaci pneumonia. The higher proportion of patients with coinfections in our study supports the use of mNGS for comprehensive early detection of respiratory infections in patients with C. psittaci pneumonia.

Clinical characteristics of 14 cases of Chlamydia psittaci pneumonia.

Among 14 patients with C. psittaci pneumonia, there were 9 critical and 5 non-critical cases. Ten patients improved clinically and were discharged to home; however, four patients died. Seven patients had a history of contact with birds or poultry. All 14 patients had a high fever as the presenting symptom, but most had a normal white blood cell count. Most of the patients had a significant increase in high-sensitivity C-reactive protein and procalcitonin levels. The lymphocyte count in the critical group was considerably lower than in the non-critical group. Patients in the critical group were more advanced in age than in the non-critical group. In addition, serum urea nitrogen, creatinine, procalcitonin, and lactate dehydrogenase levels were significantly higher in the critical group than in the non-critical group (P<0.05). The 4 patients who died had significantly increased procalcitonin levels compared to the 10 patients who survived (P<0.05). In summary, a high fever is usually the presenting complaint of patients with C. psittaci pneumonia. Such patients often progress to severe disease; however, early diagnostic confirmation by mNGS and appropriate treatment dramatically improve the prognosis. Age, lymphocyte count, procalcitonin, blood urea nitrogen, creatinine, and lactate dehydrogenase levels were shown to predict disease severity.

SNP-based high-resolution typing of Chlamydia psittaci from humans and wild birds in Sweden: circulation of the Mat116 genotype reveals the transmission mode to humans.

The incidence of Chlamydia psittaci respiratory tract infections in humans has increased in Sweden in recent years. This study aimed to identify the transmission route by genotyping C. psittaci from infected humans and birds. 42 human C. psittaci samples and 5 samples from C. psittaci-infected birds were collected. Genotyping was performed using ompA sequencing, Multi-locus sequence typing, and/or SNP-based high-resolution melting-PCR. Epidemiological data was also collected, and a phylogenetic analysis was conducted. Analysis of ompA provided limited resolution, while the SNP-based PCR analysis successfully detected the Mat116 genotype in 3/5 passerine birds and in 26/29 human cases, indicating a high prevalence of this genotype in the human population. These cases were associated with contact with wild birds, mainly through bird feeding during winter or other outdoor exposure. Human cases caused by other genotypes (psittacine and pigeon) were less common and were linked to exposure to caged birds or pigeons. The SNP-genotype Mat116 is rare, but predominated in this study. The use of SNP-based PCR provided a better understanding of the C. psittaci transmission from birds to humans compared to ompA analysis. In Sweden, human psittacosis appears mainly to be transmitted from garden birds during bird feeding in the winter season.

Chlamydia psittaci Pneumonia in a patient with motor neuron disease: a case report.

BACKGROUND: Motor neuron disease (MND) is a fatal neurodegenerative disorder that leads to progressive loss of motor neurons. Chlamydia psittaci (C. psittaci) is a rare etiology of community-acquired pneumonia characterized primarily by respiratory distress. We reported a case of C. psittaci pneumonia complicated with motor neuron disease (MND). CASE PRESENTATION: A 74-year-old male was referred to the Shaoxing Second Hospital at January, 2022 complaining of fever and fatigue for 2 days. The patient was diagnosed of MND with flail arm syndrome 1 year ago. The metagenomic next-generation sequencing (mNGS) of sputum obtained through bedside fiberoptic bronchoscopy showed C. psittaci infection. Then doxycycline was administrated and bedside fiberoptic bronchoscopy was performed to assist with sputum excretion. Computed Tomography (CT) and fiberoptic bronchoscopy revealed a significant decrease in sputum production. On day 24 after admission, the patient was discharged with slight dyspnea, limited exercise tolerance. One month later after discharge, the patient reported normal respiratory function, and chest CT showed significant absorption of sputum. CONCLUSIONS: The mNGS combined with bedside fiberoptic bronchoscopy could timely detect C. psittaci infection. Bedside fiberoptic bronchoscopy along with antibiotic therapy may be effective for C. psittaci treatment.

Engineering of the LAMP-CRISPR/Cas12b platform for Chlamydia psittaci detection.

Introduction. Chlamydia psittaci (C. psittaci) is a zoonotic infection, that causes psittacosis (parrot fever) in humans, leading to severe clinical manifestations, including severe pneumonia, adult respiratory distress syndrome, and, in rare cases, death.Gap Statement. Rapid, sensitive and specific detection of C. psittaci facilitates timely diagnosis and treatment of patients.Aim. This study aimed to engineer the LAMP-CRISPR/Cas12b platform for C. psittaci detection.Methodology. The loop-mediated isothermal amplification (LAMP) technique and clustered regularly interspaced short palindromic repeats-CRISPR associated protein 12b (CRISPR-Cas12b) assay were combined to establish two-step and one-tube LAMP-CRISPR/Cas12b reaction systems, respectively, for rapidly detecting C. psittaci.Results. The two-step and one-tube LAMP-CRISPR/Cas12b assay could complete detection within 1 h. No cross-reactivity was observed from non-C. psittaci templates with specific LAMP amplification primers and single-guide RNA (sgRNA) targeting the highly conserved short fragment CPSIT_0429 gene of C. psittaci. The detection limits of the two-step and one-tube LAMP-CRISPR/Cas12b reaction were 102 aM and 103 aM, respectively. The results were consistent with qPCR for nucleic acid detection in 160 clinical samples, including 80 suspected C. psittaci samples, kept in the laboratory.Conclusions. The LAMP-CRISPR/Cas12b assay developed in this study provides a sensitive and specific method for rapidly detecting C. psittaci and offers technical support for its rapid diagnosis.

Chlamydia psittaci: an emerging cause of equine abortion and fatal neonatal illness in south-eastern Australia.

While well known as a zoonotic pathogen of birds, Chlamydia psittaci is less well recognised as a cause of abortion in mares and severe infection in foals. However, in the past decade it has been causing epizootics of both in south-eastern Australia, as Charles El-Hage and James Gilkerson explain.

[Clinical characteristics of a case of severe pneumonia caused by coinfection of COVID-19 and Chlamydia Psittaci].

A 69-year-old female patient was admitted to the Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Xuzhou Medical University due to a "cough and fever for eight days". On admission, a coronavirus disease (COVID-19) nucleic acid test was positive, and a chest CT scan showed progressive patchy shadows and consolidation shadows in both lungs. Arterial blood gas analysis showed type Ⅰ respiratory failure. The primary diagnosis was severe community-acquired pneumonia in an older adult without underlying disease. However, oxygen inhalation, steroid, anti-inflammatory, and antibacterial empirical treatment with piperacillin/tazobactam was ineffective. Metagenomic next-generation sequencing of bronchoscopy alveolar lavage fluid showed Chlamydia psittaci(C. psittaci). Severe pneumonia was confirmed, caused by coinfection with severe acute respiratory syndrome coronavirus 2 and C. psittaci. A combination of doxycycline and moxifloxacin significantly improved the targeted and symptomatic treatment of the underlying cause. After discharge, the patient recovered within four weeks of follow-up. Therefore, clinicians should be alert to the possibility of coinfection of C. psittaci in patients already diagnosed with COVID-19.

Clinical features of psittacosis in 46 Chinese patients / Características clínicas de 46 pacientes con psittacitis China

Background: Psittacosis is a relatively uncommon cause of community-acquired pneumonia, often leading to diagnostic difficulty.Methods: A retrospective study was conducted on the clinical features of psittacosis patients in China. Forty-six cases of Chlamydophila psittaci infection with atypical pneumonia of varying severity in the last two years were described retrospectively.Results: Fever, relative bradycardia, and other systemic upsets were the main clinical presentation. The most common radiographic abnormality was segmental or lobar shadowing or consolidation. The total white cell counts were usually normal or slightly increased. The concentration of creatine kinase, C reactive protein, and lactic dehydrogenase increased, while albumin decreased remarkably. These cases exhibited good recovery after being treated with tetracycline or quinolone antibiotics.Conclusion: These features may help differentiate psittacosis from other traditional bacterial pneumonia. However, they do not provide a definitive diagnosis. Psittacosis diagnosis must perform the whole-genome sequencing for Chlamydophila psittaci in respiratory, blood, or sputum specimens. Increased awareness of psittacosis can shorten diagnostic delays and improve patient outcomes.(AU)

Antecedentes: La psitacosis es una causa relativamente poco común de neumonía adquirida en la comunidad, y a menudo conduce a dificultades diagnósticas.Métodos: Se realizó un estudio retrospectivo sobre las características clínicas de los pacientes con psitacosis en China, en el que se describen retrospectivamente 46 casos de infección por Chlamydia psittaci con neumonía atípica de gravedad variable en los últimos dos años.Resultados: La fiebre, la bradicardia relativa y otros trastornos sistémicos fueron la presentación clínica principal. La anomalía radiográfica más común fue el sombreado o consolidación segmentaria o lobular. Los recuentos totales de glóbulos blancos fueron generalmente normales o ligeramente aumentados. Las concentraciones de creatina quinasa, proteína C reactiva y deshidrogenasa láctica aumentaron, mientras que la albúmina disminuyó notablemente. Estos casos mostraron una buena recuperación después de ser tratados con antibióticos de tetraciclina o quinolona.Conclusión: Estas características pueden ayudar a diferenciar la psitacosis de otras neumonías bacterianas tradicionales. Sin embargo, no proporcionan un diagnóstico definitivo. El diagnóstico de psitacosis debe realizar la secuenciación del genoma completo de Chlamydia psittaci en muestras respiratorias, sanguíneas o de esputo. Una mayor conciencia de la psitacosis puede acortar los retrasos en el diagnóstico y mejorar los resultados de los pacientes.(AU)

Case Report: Metagenomic next-generation sequencing applied in diagnosing psittacosis caused by Chlamydia psittaci infection.

Background: Chlamydia psittaci is the causative agent of psittacosis in humans, while its rapid identification is hampered due to the lack of specificity of laboratory testing methods. Case presentation: This study reports four cases of C. psittaci infection after contact with a domestic parrot, all belonging to the same family. Common manifestations like fever, cough, headache, nausea, and hypodynamia appeared in the patients. Metagenomic next-generation sequencing (mNGS) aided the etiological diagnosis of psittacosis, revealing 58318 and 7 sequence reads corresponding to C. psittaci in two cases. The detected C. psittaci was typed as ST100001 in the Multilocus-sequence typing (MLST) system, a novel strain initially reported. Based on the results of pathogenic identification by mNGS, the four patients were individually, treated with different antibiotics, and discharged with favorable outcomes. Conclusion: In diagnosing psittacosis caused by a rare C. psittaci agent, mNGS provides rapid etiological identification, contributing to targeted antibiotic therapy and favorable outcomes. This study also reminds clinicians to raise awareness of psittacosis when encountering family members with a fever of unknown origin.

Whole genome sequencing characteristics of Chlamydia psittaci caprine AMK-16 strain, a promising killed whole cell veterinary vaccine candidate against chlamydia infection.

Chlamydia psittaci is a primary zoonotic pathogen with a broad host range causing severe respiratory and reproductive system infection in animals and humans. To reduce the global burden of C. psittaci-associated diseases on animal welfare and health and to control the pathogen spread in husbandry, effective vaccines based on promising vaccine candidate(s) are required. Recently, the caprine C. psittaci AMK-16 strain (AMK-16) demonstrated a high level of protection (up to 80-100%) in outbred mice and pregnant rabbits immunized with these formaldehyde-inactivated bacteria against experimental chlamydial wild-type infection. This study investigated the molecular characteristics of AMK-16 by whole-genome sequencing followed by molecular typing, phylogenetic analysis and detection of main immunodominant protein(s) eliciting the immune response in mouse model. Similarly to other C. psittaci, AMK-16 harbored an extrachromosomal plasmid. The whole-genome phylogenetic analysis proved that AMK-16 strain belonging to ST28 clustered with only C. psittaci but not with Chlamydia abortus strains. However, AMK-16 possessed the insert which resulted from the recombination event as the additional single chromosome region of a 23,100 bp size with higher homology to C. abortus (98.38-99.94%) rather than to C. psittaci (92.06-92.55%). At least six of 16 CDSs were absent in AMK-16 plasticity zone and 41 CDSs in other loci compared with the reference C. psittaci 6BC strain. Two SNPs identified in the AMK-16 ompA sequence resulted in MOMP polymorphism followed by the formation of a novel genotype/subtype including three other C. psittaci strains else. AMK-16 MOMP provided marked specific cellular and humoral immune response in 100% of mice immunized with the inactivated AMK-16 bacteria. Both DnaK and GrpE encoded by the recombination region genes were less immunoreactive, inducing only a negligible T-cell murine immune response, while homologous antibodies could be detected in 50% and 30% of immunized mice, respectively. Thus, AMK-16 could be a promising vaccine candidate for the development of a killed whole cell vaccine against chlamydiosis in livestock.

Chlamydia psittaci seropositivity in workers exposed to birds and review of the literature: Evidence of circulation in Antioquia / Seropositividad de Chlamydia psittaci en trabajadores expuestos a aves y revisión de la literatura: evidencia de circulación en Antioquia.

Introduction: Psittacosis is a zoonotic disease caused by Chlamydia psittaci, a bacterium classified as an agent with bioterrorist potential. It has caused multiple outbreaks in exposed poultry workers around the world. Colombia has no epidemiological follow-up of the infection and a big knowledge gap. Objectives: To determine the antibodies' frequency against C. psittaci in workers with occupational exposure to birds and to review the literature on studies conducted in Colombia. Materials and methods: We conducted a cross-sectional descriptive study with analytical intent on workers in contact with birds and reviewed the related literature in Colombia. IgM and IgG serum antibodies against C. psittaci were detected by microimmunofluorescence. The sociodemographic and exposure characteristics were expressed as frequencies and summary measures. Associated factors were explored by bivariate and multivariate analysis. The scientific and gray literature review was done with a structured search. Results: We analyzed 54 workers in contact with birds. Antibody prevalence was 31.5%. Slaughtering and evisceration by non-veterinarians was a risk factor for antibody presence. There are only four previous studies on C. psittaci in Colombia. Conclusions: Here, we present the first evidence of C. psittaci circulation among workers exposed to birds in Antioquia and the second report in the country. These findings contribute to the "One Health" public health strategy.

Introducción: La psitacosis es una enfermedad zoonótica causada por Chlamydia psittaci. Esta bacteria es catalogada como un agente con potencial bioterrorista y ha causado múltiples brotes en trabajadores con exposición laboral a aves en diferentes lugares del mundo. En Colombia, no se hace seguimiento epidemiológico de la infección y existe una gran brecha en el conocimiento. Objetivos: Determinar la frecuencia de anticuerpos contra C. psittaci en trabajadores con exposición laboral a aves y sus factores asociados. Además, revisar la literatura en relación con los estudios sobre el tema realizados en Colombia. Materiales y métodos: Se llevó a cabo un estudio descriptivo, transversal, con intención analítica, en trabajadores en contacto con aves y se revisó la literatura científica relacionada en Colombia. Se detectaron anticuerpos IgM e IgG contra C. psittaci en suero por microinmunofluorescencia. La descripción de las características sociodemográficas y de exposición se hizo con frecuencias y medidas de resumen. Se exploraron factores asociados por análisis bivariados y multivariados. La revisión de la literatura científica y gris se hizo con búsqueda estructurada. Resultados: Se analizaron 54 trabajadores en contacto con aves y se encontró una prevalencia de anticuerpos del 31,5 %. El ejercer funciones de sacrificio y faenado de las aves sin ser médico veterinario fue un factor de riesgo para la presencia de anticuerpos. Solo se encontraron cuatro estudios previos sobre C. psittaci hechos en Colombia. Conclusiones: Este estudio constituye la primera evidencia de la circulación de C. psittaci en trabajadores en contacto con aves en Antioquia y el segundo reporte en el país. Estos hallazgos aportan desde la salud pública a la estrategia One Health.

MiR-184 targeting FOXO1 regulates host-cell oxidative stress induced by Chlamydia psittaci via the Wnt/ß-catenin signaling pathway.

Chlamydia psittaci is a human pathogen that causes atypical pneumonia after zoonotic transmission. We confirmed that C. psittaci infection induces oxidative stress in human bronchial epithelial (HBEs) cells and explored how this is regulated through miR-184 and the Wnt/ß-catenin signaling pathway. miR-184 mimic, miR-184 inhibitor, FOXO1 siRNA, or negative control sequence was transfected into HBE cells cultured in serum-free medium using Lipofectamine 2000. Then, prior to the cells were infected with C. psittaci 6BC, and the cells were treated with or without 30 µM Wnt/ß-catenin inhibitor ICG-001. Quantification of reactive oxygen species, malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione was carried out according to the manufacturer's protocol using a corresponding assay kit. The outcome of both protein and gene was measured by western blotting or real-time fluorescence quantitative PCR. In C. psittaci-infected HBE cells, miR-184 was upregulated, while one of its target genes, FOXO1, was downregulated. ROS and MDA levels increased, while SOD and GSH contents decreased after C. psittaci infection. When miR-184 expression was downregulated, the level of oxidative stress caused by C. psittaci infection was reduced, and the Wnt/ß-catenin signaling pathway was inhibited. The opposite results were seen when miR-184 mimic was used. Transfecting with FOXO1 siRNA reversed the effect of miR-184 inhibitor. Moreover, when the Wnt/ß-catenin-specific inhibitor ICG-001 was used, the level of oxidative stress induced by C. psittaci infection was significantly suppressed. miR-184 can target FOXO1 to promote oxidative stress in HBE cells following C. psittaci infection by activation of the Wnt/ß-catenin signaling pathway.

Chlamydia psittaci -Induced Reactive Infectious Mucocutaneous Eruption With Ocular Involvement.

INTRODUCTION: This report highlights a postinfectious mucocutaneous inflammatory response involving the ocular surface and adnexa after Chlamydophila psittaci exposure. CASE DESCRIPTION: A 35-year-old man presented after a prodrome of upper respiratory symptoms with rash and mucocutaneous blistering involving the ocular and oral mucosa, causing pseudomembranous conjunctivitis and corneal epithelial defects. Extensive inflammatory and infectious workup suggested recent C. psittaci infection. The patient was treated with doxycycline and supportive therapy, whereas the ocular surface was treated with lubrication and prophylactic antibiotics. In follow-up, he has retained excellent visual acuity but required scleral contact lenses to control ocular surface symptoms because of fibrotic changes of the marginal conjunctiva. DISCUSSION: Such blistering inflammation has most commonly been described after pediatric respiratory infections because of Mycoplasma pneumoniae with additional instances related to Chlamydia pneumoniae , Epstein-Barr virus, influenza B, and other stimuli . To the best of our knowledge, this is the first reported case of C. psittaci- induced reactive infectious mucocutaneous eruption (RIME). RIME is a rare parainfectious inflammatory condition with sequelae frequently involving the periocular mucosa. Although systemic and nonocular adverse outcomes in this condition tend to be self-limited, the impact on the ocular surface may be severe, and the consequences to vision may be ongoing, especially if not treated aggressively at the outset.

Seropositividad de Chlamydia psittaci en trabajadores expuestos a aves y revisión de la literatura: evidencia de circulación en Antioquia / Chlamydia psittaci seropositivity in workers exposed to birds and review of the literature: Evidence of circulation in Antioquia

Introducción. La psitacosis es una enfermedad zoonótica causada por Chlamydia psittaci. Esta bacteria es catalogada como un agente con potencial bioterrorista y ha causado múltiples brotes en trabajadores con exposición laboral a aves en diferentes lugares del mundo. En Colombia, no se hace seguimiento epidemiológico de la infección y existe una gran brecha en el conocimiento. Objetivos. Determinar la frecuencia de anticuerpos contra C. psittaci en trabajadores con exposición laboral a aves y sus factores asociados. Además, revisar la literatura en relación con los estudios sobre el tema realizados en Colombia. Materiales y métodos. Se llevó a cabo un estudio descriptivo, transversal, con intención analítica, en trabajadores en contacto con aves y se revisó la literatura científica relacionada en Colombia. Se detectaron anticuerpos IgM e IgG contra C. psittaci en suero por microinmunofluorescencia. La descripción de las características sociodemográficas y de exposición se hizo con frecuencias y medidas de resumen. Se exploraron factores asociados por análisis bivariados y multivariados. La revisión de la literatura científica y gris se hizo con búsqueda estructurada. Resultados. Se analizaron 54 trabajadores en contacto con aves y se encontró una prevalencia de anticuerpos del 31,5 %. El ejercer funciones de sacrificio y faenado de las aves sin ser médico veterinario fue un factor de riesgo para la presencia de anticuerpos. Solo se encontraron cuatro estudios previos sobre C. psittaci hechos en Colombia. Conclusiones. Este estudio constituye la primera evidencia de la circulación de C. psittaci en trabajadores en contacto con aves en Antioquia y el segundo reporte en el país. Estos hallazgos aportan desde la salud pública a la estrategia One Health.

Introduction. Psittacosis is a zoonotic disease caused by Chlamydia psittaci, a bacterium classified as an agent with bioterrorist potential. It has caused multiple outbreaks in exposed poultry workers around the world. Colombia has no epidemiological follow-up of the infection and a big knowledge gap. Objectives. To determine the antibodies' frequency against C. psittaci in workers with occupational exposure to birds and to review the literature on studies conducted in Colombia. Materials and methods. We conducted a cross-sectional descriptive study with analytical intent on workers in contact with birds and reviewed the related literature in Colombia. IgM and IgG serum antibodies against C. psittaci were detected by microimmunofluorescence. The sociodemographic and exposure characteristics were expressed as frequencies and summary measures. Associated factors were explored by bivariate and multivariate analysis. The scientific and gray literature review was done with a structured search. Results. We analyzed 54 workers in contact with birds. Antibody prevalence was 31.5%. Slaughtering and evisceration by non-veterinarians was a risk factor for antibody presence. There are only four previous studies on C. psittaci in Colombia. Conclusions. Here, we present the first evidence of C. psittaci circulation among workers exposed to birds in Antioquia and the second report in the country. These findings contribute to the "One Health" public health strategy.

Case Report: Clinical analysis of a cluster outbreak of chlamydia psittaci pneumonia.

Objective: To explore the clinical characteristics and prognosis of clustered cases of psittacosis pneumonia. Method: We retrospectively analyzed the clinical data of a cluster outbreak of psittacosis pneumonia. The analysis included epidemiological data, clinical symptoms, laboratory results, and prognosis. The diagnosis was made using mNGS and nested PCR technology. Result: Of the four cases, two had direct contact with diseased poultry while the other two did not. All cases presented with more than 39.5 °C fever and chills. Additionally, significant increases in C-reactive protein, ferritin, creatine kinase, and lactate dehydrogenase were observed in all cases, while absolute lymphocyte count decreased. Case 2 also had increased calcitonin levels. Acute respiratory failure occurred during the treatment of case 1 and case 2, leading to tracheal intubation and ventilator-assisted ventilation. Unfortunately, case 2 passed away due to sepsis and multiple organ dysfunction, while the other cases had a positive prognosis. Conclusion: mNGS facilitated the early diagnosis of psittacosis pneumonia. It is important to note that there is still a substantial risk of human-to-human transmission in psittacosis pneumonia. Absolute lymphocyte count and calcitonin levels can predict the severity and prognosis of the disease.