ABSTRACT
@#Abstract: Objective To analyze the clinical characteristics of Chlamydia psittaci pneumonia and improve the diagnosis and treatment skills of clinicians on this disease. Methods The clinical data of thirty-nine Chlamydia psittaci pneumonia cases detected by metagenomic next-generation sequencing (mNGS) from September 2020 to January 2022 at the Affiliated Hospital of Southwest Medical University were retrospectively analyzed. Results There was a history of poultry exposure in 89.7%(35 cases) of the patients. The most common clinical manifestations were high fever (92.3%, 36), cough (76.9%,30), muscle soreness (48.7%,19), headache (38.5%,15), etc. Laboratory examinations showed 76.9% of patients had a normal leukocyte count, and 76.9% had decreased lymphocyte count, often accompanied by elevated C-reactive protein (100%), procalcitonin (97.4%), interleukin-6 (95.8%), interleukin-10 (95.8%), alanine aminotransferase (74.4%), and aspartate aminotransferase (84.6%). Univariate analysis indicated that there were statistically significant differences in the levels of aspartate transaminase, blood urea nitrogen, C-reactive protein, and procalcitonin between severe pneumonia patients and non-severe pneumonia patients（P<0.05）. Multivariate logistic regression analysis showed that an elevated blood urea nitrogen (OR=4.899) had guiding significance for predicting the occurrence of severe pneumonia. Bronchoscopy examination showed no abnormalities in 53.6% of the patients. The imaging manifestations of pulmonary lesions were mainly lobar pneumonia (61.5%) and air bronchograms (94.9%). Therapeutically, it was sensitive to tetracyclines, macrocyclic lactones, and fluoroquinolones. A total of 84.6%(33 cases) of the patients were cured and discharged from the hospital at the end of the treatment. Conclusion Chlamydia psittaci pneumonia is a zoonotic disease that can be detected by mNGS. An elevated blood urea nitrogen level has guiding significance for predicting the occurrence of severe pneumonia. Empirically-selected regimens based on doxycycline are effective for the treatment of Chlamydia psittaci pneumonia.
ABSTRACT
Objective:To analyze the clinical characteristics of Chlamydia psittaci pneumonia in the elderly, and factor related to the disease severity. Methods:Clinical data of 32 elderly patients with Chlamydia pneumoniae pneumonia admitted in the First People′s Hospital of Xiaoshan District from January 2019 to January 2021 were retrospectively analyzed. The patients were diagnosed by the second generation sequencing using bronchoalveolar lavage fluid (BALF) samples. There were 17 patients in moderate group and 15 patients in severe group; the liver function, muscle enzymes, imaging and lymphocyte subsets of the two groups were compared. Results:There were no significant differences in the age, gender and basic diseases, bird contact history, flaccid fever and dry cough symptoms between two groups, while there were significant differences in mental symptoms and gastrointestinal symptoms between the two groups ( P=0.032, 0.018). There were significant differences in ALT , AST, LDH , CK , CK-MB, CRP, BNP , troponin-T and PCT between the two groups (all P<0.001). The increase of leukocytes was not significant in both groups. The moderate group was dominated by single lobe involvement, while the severe group was dominated by multi lobe involvement and pleural effusion ( P=0.043, 0.015, 0.023). The total lymphocytes, T lymphocytes, CD4 + T cells, CD8 + T cells, CD4 +/CD8 + ratio, NK cells, B cells, CD4 +CD8 + double positive T cells decreased in both groups, while those in the severe group decrease more markedly ( P<0.05). CD4 -CD8 - double negative T cells were higher in the severe group than those in the moderate group ( P<0.001). CD4 +/CD8 + ratio and CD4 -CD8 - double negative T cells were correlated with severity index PSI and CURB-65 ( P<0.05). Conclusions:The liver function, muscle enzyme, lymphocyte immune function in patients with Chlamydia psittaci pneumonia are impaired, which were more markedly in severe patients. The multileaf infiltration and increased procalcitonin may indicate the severe pneumonia. CD4 +/CD8 + ratio and CD4 -CD8 - double negative T cells are correlated with the severity of pneumonia.