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 explore the clinical value of metagenomic next-generation sequencing (mNGS) in the diagnosis and treatment of severe and complex infection of malignant hematological disorder. Methods The mNGS test results, traditional etiology test results and general clinical data of inpatients with malignant hematological disorder in the Department of Hematology, the Affiliated Hospital of Southwest Medical University between June 2020 and February 2022 were retrospectively analyzed. To explore the clinical application value of mNGS in the diagnosis and treatment of severe complicated infection of hematological disorder. Results A total of 21 patients were included. The samples included 18 peripheral blood samples, 2 pleural fluid samples and 1 alveolar lavage fluid sample. In the included patients, through mNGS, pathogenic bacteria were directly detected in 17 patients, including 8 fungi, 9 bacteria and 10 viruses, of which 9 were mixed infections. The positive rate (81.0% vs. 33.3%, P=0.002), sensitivity (85.7% vs. 30.0%), granulocytopenia (9 vs. 3 cases, P=0.031) and the types of pathogen (Z=−3.416, P=0.001) detected by mNGS were all higher than those by traditional method. The infection control of 17 patients improved in varying degrees after adjusting the treatment plan according to the test results. ConclusionsmNGS has significantly higher detection rate and sensitivity for bacteria, fungi, viruses and mixed infections. Compared with the traditional method, mNGS has more efficient characteristics. Its clinical application can further improve the diagnosis and treatment efficiency of severe complicated infection of malignant hematological disorder, and thus improve the survival rate of patients.
Objective To analyze the difference of sputum flora between acute exacerbation and stable chronic obstructive pulmonary disease (COPD) patients basing on metagenomic next generation sequencing (mNGS), and its relationship with clinical indicators. The role of sputum flora of COPD patients in unexplained deterioration was explored, so as to find a targeted treatment plan. Methods From December 2021 to June 2022, 54 COPD patients who had a history of smoking were recruited, including 25 patients in stable COPD (SCOPD group) and 29 patients in acute exacerbation (AECOPD group). The sputum was collected and sequenced by mNGS, and the difference of sputum flora between the two groups was compared. Results Compared with SCOPD group, the evenness of sputum flora (Shannon index) in AECOPD group decreased significantly (P=0.019, Mann-Whitney U test). At the phylum level, the relative abundance of Fusobacteria in AECOPD group was significantly lower than that in SCOPD group (Z=–2.669, P=0.008). At genus level, compared with SCOPD group, the relative abundance of Fusobacterium and Haemophilus in AECOPD group decreased significantly (Z=–3.062, P=0.002; Z=–2.143, P=0.032), and the relative abundance of Granulicatella increased significantly (Z=–2.186, P=0.029). At species level, the relative abundance of sputum Haemophilus parainfluenzae, Moraxella catarrhalis and Haemophilus influenzae in AECOPD group was significantly lower than that in SCOPD group (Z=–2.230, P=0.026; Z=–2.125, P=0.034; Z=–2.099, P=0.036). At the time of acute exacerbation of COPD, the relative abundance of Gemella in sputum was positively correlated with forced expiratory volume in first second/forced vital capacity (FEV1/FVC) and body mass index (r=0.476, P=0.009; r=0.427, P=0.021), which was negatively correlated with nutrition risk screening 2002 (r=–0.570, P=0.001). The relative abundance of Neisseria and Neisseria subflava was negatively correlated with GOLD grade (r=–0.428, P=0.020; r=–0.455, P=0.013). The relative abundance of Rothia aeria was posotively correlated with C-reactive peotein (r=0.388, P=0.038). Conclusions There are significant differences of sputum flora in phylum, genus and species level between stable and acute exacerbation COPD patients. The evenness of sputum flora in COPD patients in acute exacerbation is significantly lower than that in patients in stable stage. Fusobacteria, Fusobacterium, Gemella and Nesseria (Neisseria subflava) may play a beneficial role in COPD, while Rothia aeria may be associated with COPD exacerbation.
In recent years, with the wide application of metagenomics next-generation sequencing, more and more rare pathogens have been detected in our clinical work, including non-tuberculous Mycobacterium, Corynebacterium, Fusarium, Cryptococcus pneumoniae, human herpes virus, torque teno virus, parvovirus, Tropheryma whipplei, Bartonella, Chlamydia psittaci, etc. It is difficult to determine whether these rare pathogens are clinically significant and need treatment. This article puts forward some suggestions and discussions on the diagnosis and treatment of pulmonary infections with some rare pathogens.