ObjectiveTo improve the understanding of psittacosis, the clinical data of 8 cases are reviewed. The application of pathogen metagenomics next-generation sequencing (mNGS) in the diagnosis of nocardiosis is also investigated.MethodsThe clinical data of eight patients with psittacosis diagnosed by mNGS in Nanjing Drum Tower Hospital from January 2018 to May 2020 were reviewed. The clinical characteristics, laboratory examination characteristics and imaging changes were analyzed, and the treatment outcome was followed-up.ResultsAmong the eight cases, there were six males and two females, aged 43～83 years old, with an average age of 64±12 years old. Six of them had a clear history of poultry exposure. The major clinical manifestations were fever, cough, dyspnea, etc. Chest high-resolution computed tomography (HRCT) may have solid shadow, ground glass like shadow. Chlamydia psittaci was detected by mNGS in eight patients’ bronchoalveolar lavage fluid. Minocycline or moxifloxacin were administrated, six patients were discharged after their condition improved, and two patients died.ConclusionsThe incidence of psittacosis is low, and its clinical manifestations lack specificity. In the course of the disease, there may be different degrees of fever, cough, sputum, dyspnea and other symptoms. The lungs can be heard with wet rales, chest HRCT can be seen ground glass shadow, consolidation shadow, accompanied by air bronchogram. Chlamydia psittaci can be detected in alveolar lavage fluid by mNGS. The patients need to be treated for a long time, lasting at least 10 to 14 days. Tetracycline drugs should be the first choice, and can be combined with other antibiotics with activity against gram-positive and gram-negative bacteria in critical patients.
Objective To investigate the clinical features, imaging features, diagnosis and treatment of severe Chlamydia psittaci pneumonia in order to facilitate early diagnosis and treatment and reduce the mortality rate. Methods The clinical data of 7 patients with severe Chlamydia psittaci pneumonia diagnosed in Fujian Provincial Hospital from October 2019 to July 2020 were retrospectively analyzed. Results Among the 7 cases, there were 5 males and 2 females, aged 59 to 69 years. The main clinical manifestations were fever, cough, sputum, dyspnea, and some symptoms of digestive and nervous systems. The total number of white blood cells was normal or slightly higher in 7 patients, the absolute value of lymphocytes was decreased, C-reactive protein was significantly increased, and respiratory failure occurred in all 7 patients. Chest CT showed large patchy consolidation shadows accompanied by air bronchogram signs, which progressed in a short period, followed by a small amount of pleural effusion. The specific DNA fragments of Chlamydia psittaci were identified by metagenomic next-generation sequencing in all 7 patients. Six patients were treated with doxycycline, 1 with azithromycin, and 7 relieved with improved symptoms and imaging. Conclusions For elderly patients with acute onset, high fever with cough, difficulty breathing, especially with a history of poultry or birds, whose chest images suggest large consolidation effusion shadows, empirical antibiotic for community-acquired pneumonia is invalid, psittacosis chlamydia pneumonia should be highly suspected. Therefore second-generation sequencing of respiratory secretions is necessary so as to determine the pathogens. Tetracycline class antibiotic treatment should be given as soon as possible after the diagnosis of psittacosis chlamydia pneumonia.
Objective To investigate the clinical manifestations, diagnosis, treatment and prognosis of psittacosis patients. Methods The clinical features, treatment and prognosis of severe pneumonia caused by Chlamydia psittaci were analyzed and relevant literatures were reviewed. Results An 83-year-old male with a history of type 2 diabetes mellitus was admitted to the hospital for "fever, cough for 5 days and dyspnea for 3 days". Chest CT showed a large mass of increased density in the right lung; CD4+ T lymphocytes had an absolute value of 23 cells/μL; Blood gas analysis showed type Ⅰ respiratory failure; Chlamydia psittaci was detected by metagenomic next-generation sequencing. The patient was diagnosed of severe pneumonia (Chlamydia psittaci), type 2 diabetes mellitus, suspected central nervous system infection. This patient was treated with doxycycline and macrolides antibiotics and discharged from hospital after complete recovery. Literature review showed that patients got infected from contacting sick bird, manifested with multiple system involvement. Respiratory symptoms were common, while central nervous system infection seemed to be rare. The diagnosis of psittacosis depended on serology, nucleic acid detection, pathogen isolation and culture. Metagenomic next-generation sequencing had superiority in the diagnosis of psittacosis. Tetracyclines were the preferable treatment, such as doxycycline or tetracycline, with a duration of at least 10 to 14 days. The prognosis of psittacosis was well, and most of the severe and even life-threatening cases were caused by unclear diagnosis and delayed treatment, and the overall mortality rate was about 1%. Conclusions Psittacosis is one kind of zoonoses. History of poultry exposure is helpful in diagnosis, and metagenomic next-generation sequencing has advantages in diagnosing psittacosis. Tetracyclines are preferred with adequate course of treatment. The overall prognosis is good.
Objective To analysis and explore the value of metagenomics next-generation sequencing (mNGS) and clinical characteristics of Chlamydia psittaci (C. psittaci) pneumonia. Methods Totally 5 patients who were diagnosed with C. psittaci pneumonia and were treated in the Department of Respiratory and Critical Care Medicine and the Department of Infectious Diseases of Huazhong University of Science and Technology Union Shenzhen Hospital from Febuary 2021 to March 2021 were enrolled in the study. The clinical data of the patients were analyzed, and the clinical characteristics of the disease and treatment experience were summarized. Results The main symptoms of the 5 patients were high fever and cough, 4 of them had a history of raising parrots. The white blood cell and the neutrophils were mostly normal or slightly increased, the C reactive protein and erythrocyte sedimentation rate were significantly increased. The chest CT showed exudation and consolidation of one or several lung lobes. The serious patients might develop respiratory failure, if they were not treated by effective antibiotics. The diagnosis was based on clinical manifestations, contact history and alveolar lavage fluid that were detected by mNGS technology of C. psittaci nucleic acid sequence. The accuracy of detecting pathogens in alveolar lavage fluid by mNGS was high. In addition, mNGS could also identify other bacteria or viruses. After the timely adjustment of treatment, the condition of the patients was improved relied on tetracycline drugs or quinolone drugs, which shortened the diagnosis time and course of C. psittaci pneumnonia and reduced the use of unnecessary antibacterial drugs. Conclusions mNGS is of great significance in diagnosing C. psittaci pneumonia. The timely use of appropriate antibacterial drugs can achieve favorable therapeutic effect.
Objective To explore the clinical characteristics of Chlamydia psittaci pneumonia. Methods From January 2020 to March 2023, 21 cases of Psittacosis from the First Affiliated Hospital of Nanjing Medical University were diagnosed via metagenomic next-generation sequencing (mNGS). They were divided into a severe group (n=10) and a non-severe group (n=11) based on diagnostic criteria for severe pneumonia, and the clinical presentation, secondary examination, treatment, and prognosis of the two groups were analyzed retrospectively. Results Among the 21 patients, there were 11 males and 10 females, with a mean age of (51.7±11.6) years. All patients had an acute onset and 12 had a confirmed history of exposure to poultry. The onset of the disease occurred in the autumn and winter seasons in 18 patients. All the patients were suffering from high fevers. Other symptoms included coughing, phlegm, tightness in the chest and fatigue. Laboratory examinations showed that the levels of leukocytes, neutrophil counts, C-reactive protein, procalcitonin, aminotransferase, creatine kinase, lactic dehydrogenase, brain natriuretic peptide precursors and D-dimer were significantly higher in the severe group than those in the non-severe group. Chest CT scans revealed varying levels of consolidation and spot shadowing with peripheral exudate in all patients. The patients in the severe group were more likely to have bilateral lung involvement, bilateral pleural effusion, cavity and mediastinal lymph node enlargement. Eleven patients received tetracycline alone, three received laudanum alone, two received respiratory quinolones alone, and five received a combination of two drugs including tetracycline. Chest CT at clinical follow-up showed absorption of lung lesions. Conclusions Chlamydia psittaci pneumonia usually occurs in the fall and winter, and most patients have a history of contact with poultry. Clinical presentation and imaging are not specified. The technology of mNGS enables early diagnosis of the disease, and neutrophil lymphocyte ratio, neutrophil-lymphocyte ratio and lactic dehydrogenase levels help assess the risk of severe disease.
Objective To analyse the clinical and pathological characteristics of Chlamydia psittaci pneumonia, and increase the comprehensive understanding of the Chlamydia psittaci pneumonia. Methods Five patients diagnosed with Chlamydia psittaci pneumonia were selected in this hospital from November 2021 to November 2022, and their clinical and pathological characteristics were analysed. Results Out of these five patients, 2 patients were male and 3 were female, with a mean age (65±9) years and length of hospital stay (11 - 13) d. The first symptom of all five patients was fever; 3 patients were complicated with hypoxemia; there were several accompanying symptoms, including chilly, shiver, fatigue, headache, cough, muscle soreness, hearing loss and so on. In the laboratory indicators, white blood cell count was not significantly abnormal, the C-reactive protein and procalcitonin were high. In the chest CT, the diseased regions were mostly located in unilateral lesions, 3 cases were on the right side; the forms included pulmonary consolidation, lung glass opacity, pleural effusion, pleural thickening, etc.; the mNGS results of bronchoalveolar lavage fluid showed the Chlamydia psittaci; the pathology of lung biopsy showed significant proliferation of fibers in the interstitial lung and partly fibrosis, with histiocytic reaction and minimal lymphocyte infiltration. Conclusion Clearly diagnosing patients with pneumonia which are suspected being infected Chlamydia psittaci as soon as earlier can prompt anti-infection treatment, and avoid further damage to the lung interstitium, eventually decrease the deterioration of lung function and progression to severe pneumonia.