Assessing the utility of the Xpert Mycobacterium tuberculosis/rifampin assay for analysis of bronchoalveolar lavage fluid in patients with suspected pulmonary tuberculosis.

BACKGROUND: There is limited research assessing the utility of the Xpert Mycobacterium tuberculosis/rifampin (MTB/RIF) assay for the analysis of bronchoalveolar lavage fluid (BALF) in Chinese patients with suspected pulmonary tuberculosis (PTB). Thus, our objective was to determine the diagnostic accuracy of the Xpert MTB/RIF assay and evaluate its utility for the determination of rifampicin resistance. METHODS: We retrospectively analyzed BALF from 214 patients with suspected PTB between January 2018 and March 2019. Using mycobacterial culture or final clinical diagnosis as the reference standard, the diagnostic accuracy of the smear microscopy (SM), tuberculosis bacillus DNA (TB-DNA), Xpert MTB/RIF assay, and the determination of rifampicin resistance based on the Xpert MTB/RIF assay were compared. RESULTS: As compared to mycobacterial culture, the sensitivity of the Xpert MTB/RIF assay, SM, and TB-DNA were 85.5% (74.2%-93.1%), 38.7% (26.6%-51.9%), and 67.7% (54.7%-79.1%), respectively. As compared to the final diagnosis, the specificity of the Xpert MTB/RIF assay, SM, and TB-DNA were 100.0% (95.9%-100.0%), 94.3% (87.1%-98.1%), and 98.9% (93.8%-100.0%), respectively. The sensitivity and specificity of the rifampicin resistance detection using the Xpert MTB/RIF assay were 100% and 98.0%, respectively, with liquid culture as the reference. CONCLUSIONS: This study demonstrates that the analysis of BALF with the Xpert MTB/RIF assay provides a rapid and accurate tool for the early diagnosis of PTB. The accuracy of diagnosis was superior compared with the SM and TB-DNA. Moreover, Xpert is a quick and accurate method for the diagnosis of rifampicin-resistant tuberculosis and can also provide more effective guidance for the treatment of PTB or multidrug-resistant tuberculosis (MDR-TB).

Differential diagnosis for suspected cases of coronavirus disease 2019: a retrospective study.

BACKGROUND: Since December 2019, the coronavirus disease 2019 (COVID-19) has infected more than 12,322,000 people and killed over 556,000 people worldwide. However, Differential diagnosis remains difficult for suspected cases of COVID-19 and need to be improved to reduce misdiagnosis. METHODS: Sixty-eight cases of suspected COVID-19 treated in Wenzhou Central Hospital from January 21 to February 20, 2020 were divided into confirmed and COVID-19-negative groups based on the results of real-time reverse transcriptase polymerase chain reaction (RT-PCR) nucleic acid testing of the novel coronavirus in throat swab specimens to compare the clinical symptoms and laboratory and imaging results between the groups. RESULTS: Among suspected patients, 17 were confirmed to COVID-19-positive group and 51 were distinguished to COVID-19-negative group. Patients with reduced white blood cell (WBC) count were more common in the COVID-19-positive group than in the COVID-19-negative group (29.4% vs 3.9%, P = 0.003). Subsequently, correlation analysis indicated that there was a significant inverse correlation existed between WBC count and temperature in the COVID-19-positive patients (r = - 0.587, P = 0.003), instead of the COVID-19-negative group. But reduced lymphocyte count was no different between the two groups (47.1% vs 25.5%, P = 0.096). More common chest imaging characteristics of the confirmed COVID-19 cases by high-resolution computed tomography (HRCT) included ground-glass opacities (GGOs), multiple patchy shadows, and consolidation with bilateral involvement than COVID-19-negative group (82.4% vs 31.4%, P = 0.0002; 41.2% vs 17.6% vs P = 0.048; 76.5% vs 43.1%, P = 0.017; respectively). The rate of clustered infection was higher in COVID-19-positive group than COVID-19-negative group (64.7% vs 7.8%, P = 0.001). Through multiplex PCR nucleic acid testing, 2 cases of influenza A, 3 cases of influenza B, 2 cases of adenovirus, 2 cases of Chlamydia pneumonia, and 7 cases of Mycoplasma pneumoniae were diagnosed in the COVID-19-negative group. CONCLUSIONS: WBC count inversely correlated with the severity of fever, GGOs, multiple patchy shadows, and consolidation in chest HRCT and clustered infection are common but not specific features in the confirmed COVID-19 group. Multiplex PCR nucleic acid testing helped differential diagnosis for suspected COVID-19 cases.

Disruption of Cdyl gene impairs mouse lung epithelium differentiation and maturation.

CDYL is a chromodomain protein that has been identified as a transcriptional co-repressor that is primarily involved in the formation of repressor complexes which coordinate histone modifications to repress gene transcription. However, most functions and mechanisms of action of the CDYL protein are unknown. In this study, we show that Cdyl-/- mice died of respiratory distress immediately at birth because of distinct abnormalities in distal lung morphogenesis which was characterized by thickened septal and expiratory alveolus atelectasis. Furthermore, Cdyl deletion in mice led to excessive proliferation of immature epithelial cells and an arrest in alveolar epithelium cell differentiation in late gestation which were associated with decreased secretion of mature surfactant proteins in alveolus. Microarray analysis showed that Cdyl gene deletion influenced the expression of genes regulating neuroactive ligand-receptor interactions, cell adhesion, and cell cycle. We validated that Cdyl repressed the transcriptional activity of Cks1 in vitro. In conclusion, Cdyl gene participates in the perinatal respiratory epithelium differentiation and maturation that is important for normal lung function at birth.

[Application of ThinPrep cytology test in the diagnosis of lung cancer].

OBJECTIVE: To explore the diagnostic value of ThinPrep cytology test (TCT) in lung cancer. METHODS: 353 cases of bronchoalveolar lavage fluid (BALF) and(or) bronchial brushing cytology (192 cases from lung cancer patients and 161 cases from benign lung disease patients) were detected with TCT and method of direct smear, respectively. The sensitivity and specificity of two methods was compared. RESULTS: The sensitivity and specificity of TCT were 39.6% and 99.4%. And which of direct smear method were 8.3% and 100%, respectively. The sensitivity of TCT was significantly higher than that of method of direct smear in the diagnosis of lung cancer (P < 0.01). There were 71 patients who underwent BALF and bronchial brushing cytology simultaneously, the sensitivity of TCT of BALF was higher than that of bronchial brushing cytology (P < 0.05). Of the 69 cases which had both TCT and histopathological results, TCT and pathology concordance rate was 84.1%. CONCLUSION: TCT has more diagnostic value in lung cancer; BALF is more preponderant than bronchial brushing cytology by TCT in the diagnosis of lung cancer.