Clinical Epidemiology, Treatment, and Prognostic Factors of Hospital-Acquired Pneumonia Caused by the Extensively Drug-Resistant Acinetobacter Baumannii.

BACKGROUND: Extensively drug-resistant Acinetobacter baumannii (XDRAB) can acquire drug resistance genes, which are rapidly cloned and transmitted, leading to worldwide spread and posing significant treatment challenges. This study aimed to clarify effective treatment methods during XDRAB infection and factors affecting patient prognosis. METHODS: Clinical features, treatment, and prognosis of 65 patients with hospital-acquired XDRAB pneumonia clinically diagnosed at Guangzhou First People's Hospital between January 2019 and December 2020 were retrospectively analyzed. RESULTS: Of 65 subjects, only 37 survived. There was no significant difference in anti-A. baumannii activity according to type or combination of antibiotics administered between patients that survived and those that died (p > 0.05). The use of antibacterial drugs during infection did not effectively improve clinical outcomes. Advanced age, multiple organ failure, and disease severity were significantly negatively correlated while effective airway management was positively associated with bacterial clearance (p < 0.05). In multivariate analysis, age and APACHE score were independent risk factors affecting prognosis. Tracheotomy during infection was a protective factor contributing to survival (p < 0.05). Advanced age and disease severity independently affected patient prognosis, while use and type of antibacterial treatment did not substantially affect the prognosis. CONCLUSIONS: Advanced age and severe disease are independent risk factors that affect patient prognosis. Timely and effective airway management is key to improving the prognosis of patients with hospital-acquired XDRAB infection.

Clinical Characteristics of Chlamydia psittaci Pneumonia Confirmed by Metagenomic Next-Generation Sequencing.

BACKGROUND: Chlamydia psittaci pneumonia has atypical clinical manifestations and the diagnosis may be missed by traditional methods of microbiological diagnosis. METHODS: Twelve cases of Chlamydia psittaci pneumonia diagnosed by metagenomic next-generation sequencing (mNGS) in Huizhou Central People's Hospital in China between January 2020 and August 2021 were reviewed and analyzed, retrospectively, using hospital records, the clinical characteristics, treatment, and prognosis. RESULTS: Ten of the 12 cases (83%) were associated with a definite history of bird/poultry contact. Common symptoms included high fever, cough, fatigue, anorexia (12/12, 100%), dyspnea (11/12, 92%), and changes in the level of consciousness and headache (5/12, 42%). There was a marked increase in C-reactive protein and D-dimer levels, but white blood cells and neutrophils were normal or slightly increased. Nine patients (75%) had liver enzyme abnormalities, and six (50%) had cardiac insufficiency and myocardial injury. There was no correlation between the mNGS sequence number of Chlamydia psittaci and the pneumonia severity. The chest imaging manifestations were mainly large areas of consolidation, predominantly in the lower lung lobes. Monotherapies or combinations of doxycycline, moxifloxacin/levofloxacin, and azithromycin were effective for treating Chlamydia psittaci pneumonia. CONCLUSIONS: The use of mNGS increases the probability of diagnosing Chlamydia psittaci pneumonia, and good prognosis can be achieved with timely use of appropriate antibiotics.

MiR-328-3p inhibits lung adenocarcinoma-genesis by downregulation PYCR1.

BACKGROUND: A vast majority of patients with NSCLC (non-small cell lung cancer) have lung adenocarcinoma (LA), and the survival rate of LA varies from 5% to 75% depending on the severity of this adenocarcinoma. PYCR1 (abnormal pyrroline-5-carboxylate reductase 1) gene and miR-328-3p have been found to be associated with cancer development. However, the underlying mechanism of interaction between miR-328-3p and PYCR1 in LA needs further investigation. METHODS: The expressions of miR-328-3p and PYCR1 in samples with LA were identified by RT-qPCR. Next, we investigated the targeting relationship between these two biological factors using luciferase assay. CCK-8, BrdU, transwell-migration, and flow cytometry assays were performed to detect cell viability, cell proliferation, cell migration and cell apoptosis in LA cells. RESULTS: We noticed that miR-328-3p expression was downregulated in LA samples. MiR-328-3p mimic restricted cell proliferation and cell migration, while it enhanced cell apoptosis. Furthermore, the overexpression of PYCR1 promoted the proliferation and migration of LA cells, but it repressed cell apoptosis. Moreover, PYCR1 directly interacted with miR-328-3p in the LA cells, and miR-328-3p restrained the expression of PYCR1, thus suppressing LA tumorigenesis. CONCLUSION: In summary, our study revealed that miR-328-3p targeting to PYCR1 suppressed the malignancy of LA cells by impeding cell proliferation and migration, while effectively promoting cell apoptosis.

Case Report: Omadacycline in the treatment of macrolide-unresponsive Mycoplasma pneumoniae pneumonia in an adolescent patient.

Omadacycline is a novel tetracycline antibiotic that exhibits good in vitro antibacterial activity against atypical pathogens such as Mycoplasma pneumoniae. It is approved for the treatment of adults with community-acquired bacterial pneumonia. However, the safety and efficacy of omadacycline in pediatric patients under 18 years of age have not yet been established. In the present paper, we report a case of pediatric community-acquired pneumonia in which initial empirical anti-infective therapy had failed. The patient received empirical anti-infective therapy with azithromycin and other antimicrobial agents upon admission but showed a poor clinical response and developed secondary tinnitus and liver dysfunction. After the confirmation of M. pneumoniae infection through metagenomic next-generation sequencing (mNGS) of bronchoalveolar lavage fluid, an antibiotic switch to omadacycline was made. Thereafter, the patient's condition improved, and no adverse reactions were observed. These findings demonstrate that mNGS enables the identification of infection-causing pathogens in patients with unresponsive pneumonia. Omadacycline can be considered as an alternative option for anti-infective therapy in pediatric M. pneumoniae pneumonia, especially when the presence of bacterial resistance, adverse drug reactions, or organ failure are taken into consideration.

Chlamydia psittaci Pneumonia-Induced Pulmonary Thrombosis: A Case Report.

Chlamydia psittaci pneumonia frequently leads to various extrapulmonary complications; however, reports of C. psittaci-pneumonia complicated by pulmonary thrombosis are uncommon. We report a case of severe C. psittaci pneumonia in a patient with a history of poultry contact and clinical manifestations including hyperpyrexia, dyspnea, and respiratory failure, which necessitated tracheal intubation for assisted ventilation. C. psittaci in bronchoalveolar lavage fluid was detected with metagenomic next-generation sequencing. Following targeted antibiotic therapy, the fever subsided, although dyspnea persisted without significant improvement, and chest pain developed. Compared to previous measurements, the D-dimer level increased, and CT pulmonary angiography revealed thromboses in the pulmonary artery trunk and left pulmonary artery. The symptoms improved after anticoagulant treatment, and the patient was discharged subsequently. This study suggests that C. psittaci infection may be associated with the formation of pulmonary thrombosis. Additional clinical data are required to support this inference. Following targeted antibiotic therapy, if persistent dyspnea, chest pain, and increased D-dimer level are present, pulmonary thrombosis should be considered, and pulmonary artery angiography can confirm the diagnosis.

Acute abdominal pain as the first symptom of Chlamydia psittaci pneumonia complicated by acute pancreatitis: a case report.

Background: Chlamydia psittaci infections primarily cause damage to the lungs but may also affect the cardiovascular system, gastrointestinal tract, liver, kidney, and brain, resulting in a variety of extrapulmonary complications. However, reports regarding C. psittaci infection-associated pancreatitis are rare. In this report, a patient with C. psittaci pneumonia complicated by acute pancreatitis is presented. Case description: The patient presented with acute upper abdominal pain and developed severe pyrexia and dyspnoea one day later. A chest computed tomography image revealed patchy consolidation in the left lung. The disease progressed rapidly, and the patient exhibited liver and kidney damage and type 1 respiratory failure within a short period of time. Metagenomic next-generation sequencing of alveolar lavage fluid revealed the presence of C. psittaci. The patient was administered doxycycline and moxifloxacin, after which the patient's abdominal pain and lung infection significantly resolved. Conclusion: This case report demonstrates that extrapulmonary C. psittaci infections due to secondary acute pancreatitis can manifest as abdominal pain, although the exact mechanisms of C. psittaci caused by acute pancreatitis remain unclear. Timely diagnoses and treatments of such infections are necessary to achieve favorable clinical outcomes.

Omadacycline for the Treatment of Severe Chlamydia psittaci Pneumonia Complicated with Multiple Organ Failure: A Case Report.

Psittacosis is a rare zoonotic disease caused by Chlamydia psittaci infection, and tetracyclines are the preferred treatment. Omadacycline is a novel tetracycline that has a strong in vitro antibacterial activity against atypical pathogens, including C. psittaci; however, clinical data for its usage are lacking. We report a patient with severe C. psittaci-induced pneumonia presenting with a high fever, muscle aches, severe hepatic and renal insufficiency, and acute respiratory failure requiring tracheal intubation and mechanical ventilation. The condition was diagnosed using metagenomic next-generation sequencing. The patient was discharged after treatment with omadacycline. The findings of this study suggest that metagenomic next-generation sequencing is valuable for the rapid and accurate diagnosis of psittacosis. With its good safety profile and no requirement for dose adjustment in special populations, omadacycline is a new option for the treatment of severe C. psittaci pneumonia. However, additional case reports are needed to support this conclusion.

Clinical and chest computed tomography features associated with severe Chlamydia psittaci pneumonia diagnosed by metagenomic next-generation sequencing: A multicenter, retrospective, observational study.

Chlamydia psittaci pneumonia is a rare disease with varying clinical presentations. Here, we aimed to investigate the clinical and chest computed tomography (CT) features of severe psittacosis pneumonia. Clinical data of 35 patients diagnosed with psittacosis pneumonia were retrospectively analyzed using metagenomic next-generation sequencing. The patients were classified into severe (n = 20) and non-severe (n = 15) groups. The median age of patients was 54 years, and 27 patients (77.1%) had a definite history of bird contact. Severe patients had more underlying comorbidities and were more prone to dyspnea and consciousness disorders than non-severe patients. The neutrophil count and D-dimer, lactate dehydrogenase, interleukin (IL)-2, IL-6, and IL-10 levels were higher, whereas the lymphocyte, CD3 + T cell, and CD4 + T cell counts, CD4+/CD8 + T cell ratio, and albumin level were substantially lower in severe patients than in non-severe patients. Chest CT findings of severe patients revealed large areas of pulmonary consolidation, and ground-glass opacities were observed in some patients, with a higher risk of involving multiple lobes of the lungs and pleural effusion. One patient died of multiple organ failure, whereas the condition of the other 34 patients improved, and they were discharged from the hospital. Patients with severe psittacosis pneumonia often have underlying comorbidities and are prone to developing dyspnea, consciousness disorder, and lesions in both lungs. Serum D-dimer, IL-2, IL-6, and IL-10 levels and lymphocyte, CD3 + T cell, and CD4 + T cell counts are associated with disease severity.

Case Report: Chlamydia psittaci pneumonia complicated by Guillain-Barré syndrome detected using metagenomic next-generation sequencing.

Psittacosis and Guillain-Barré syndrome are both rare clinical diseases with low incidence, and their combination has rarely been reported. Here, we report a case of Chlamydia psittaci pneumonia combined with Guillain-Barré syndrome. The patient initially presented with high fever, difficulty breathing, and fatigue. Chest computerised tomography indicated large consolidation opacities in both lungs. Metagenomic next-generation sequencing clearly identified the pathogen as C. psittaci. The patient's fever subsided after targeted antibiotic treatment, but difficulty breathing and fatigue worsened, and the patient developed symmetric limb numbness and weakness. Lumbar puncture, electrophysiological examination, and clinical characteristics were suggestive of Guillain-Barré syndrome, and the symptoms improved after treatment with human immunoglobulin. The results of this study suggest that metagenomic next-generation sequencing is useful for the rapid diagnosis of pulmonary infectious agents. Psittacosis is closely associated with the development of Guillain-Barré syndrome; however, more cases are needed to support this conclusion, and early targeted antibiotic treatment, immunotherapy, and basic supportive treatment are essential for improving outcomes.

[Analysis of clinical features of 16 cases with Chlamydia psittaci pneumonia].

OBJECTIVE: To analyze the clinical characteristics of Chlamydia psittaci pneumonia and to investigate the correlation between serum inflammatory biomarkers and severity of the disease. METHODS: Sixteen patients with Chlamydia psittaci pneumonia admitted to the Huizhou Municipal Central Hospital from January 2020 to July 2021 were selected as the study subjects, including 10 severe cases and 6 mild cases. Clinical data were collected and analyzed, such as baseline characteristics, clinical symptoms, laboratory inspection and chest imaging manifestations. RESULTS: (1) Thirteen Chlamydia psittaci pneumonia were associated with a definite bird or poultry contact history. Common symptoms included high fever, chill, cough, fatigue, and anorexia (16 cases), dyspnoea (12 cases), and other systemic symptoms. (2) Laboratory test results showed normal white blood cell count (WBC, 10 cases), decreased lymphocyte count (LYM, 13 cases), increased high sensitive C-reactive protein (hs-CRP, 16 cases), D-dimer (15 cases), lactate dehydrogenase (LDH, 13 cases), aspartate aminotransferase (AST, 16 cases) and alanine aminotransferase (ALT, 12 cases) levels, however, the albumin (Alb, 15 cases) lever was decreased. The numbers of CD3+ T cells and CD4+ T cells decreased in 10 patients. (3) The levels of D-dimer, interleukins (IL-2, IL-6, IL-10) in severe Chlamydia psittaci pneumonia were significantly higher than those in mild Chlamydia psittaci pneumonia [D-dimer (µg/L): 10 257±4 203 vs. 1 085±642, IL-2 (ng/L): 1.1 (0.8, 1.7) vs. 0.3 (0.1, 0.7), IL-6 (ng/L): 315 (182, 505) vs. 75 (18, 131), IL-10 (ng/L): 7.0±4.1 vs. 2.3±0.7], but the LYM was lower (×109/L: 0.4±0.1 vs. 1.1±0.4), with significant differences (all P < 0.05). (4) Chest imaging manifestations were exudative lesions and large consolidation of lungs. Large consolidation of both lungs can occur in some critically ill patients. CONCLUSIONS: Chlamydia psittaci pneumonia is mainly associated with a bird or poultry contact history. The clinical manifestations usually present high fever, dyspnea, normal or slightly increased leucocytes, and lung consolidation. The levels of LYM, D-dimer, IL-2, IL-6 and IL-10 in serum are expected to predict the severity of the Chlamydia psittaci pneumonia.