Comparison of clinical features of pulmonary infections with Mycobacterium intracellulare and Mycobacterium abscessus in tuberculosis intensive care unit / 中华临床感染病杂志

Objective To compare the clinical features of pulmonary infections with Mycobacterium intracellulare and Mycobacterium abscessus in the tuberculosis intensive care unit (ICU).Methods Clinical data of 74 patients with non-tuberculous mycobacterial pulmonary infection (NTM) admitted in tuberculosis ICU of Hangzhou Red Cross Hospital from January 2012 to May 2017 were retrospectively analyzed.There were 54 patients infected with Mycobacterial abscesses, 16 patients with Mycobacterial intracellular, 2 patients with Mycobacterium avium and 2 patients with Mycobacterium kansasii.The clinical features, imaging manifestations, treatment and prognosis of patients with Mycobacterial intracellular and Mycobacterial abscesses lung infections were compared.SPSS 21.0 software was used for statistical analysis.Survival curve analysis was performed using GraphPad Prism V 5.01.Results Among 74 patients with NTM lung disease , the infection rate of Mycobacterium abscessus was 72.87%(54/74), and the infection rate of Mycobacterium intracellular was 21.62%( 16/74 ).The age of patients with Mycobacterium intracellularis pulmonary disease was younger and the length of ICU stay was shorter than those of patients with Mycobacterium abscessus (t＝－2.729 and －6.150, P＜0.05 or ＜0.01).There was no significant difference in the gender distribution and APACHE Ⅱ scores between the two groups ( both P＞0.05).The proportion of patients with chronic obstructive pulmonary disease ( COPD) in Mycobacterium intracellularis group was significantly lower and the proportion of patients with bronchiectasis was significantly higher than those in Mycobacterial abscesses group (χ2＝3.902, P＜0.05; χ2＝23.888, P＜0.01).The proportion of patients complicated with stroke sequelae , Parkinson's disease and other central nervous system diseases ( χ2＝14.872, P＜0.01) and diabetes (χ2＝3.902, P＜0.05) in Mycobacterial abscess group was significantly higher, and that of hemoptysis was significantly lower (χ2＝9.717, P＜0.01) than those in Mycobacterium intracellularis group.Respiratory failure (93.75%) and septic shock (6.25%) were the main reasons of ICU admission for patients with Mycobacterium intracellularis lung disease; while respiratory failure (90.74%), heart failure (11.11%) and renal failure (1.85%) were main reasons of ICU admission for patients with Mycobacterial abscesses; there were no significant differences in the causes of ICU admission between the two groups ( all P＞0.05).The proportion of NTM isolated from patients with Mycobacterial intracellular lung disease, prior to mechanical ventilation was significantly higher than that of patients with Mycobacterial abscess ( χ2＝30.366, P ＜0.01 ).In imaging, the proportion of bronchiectasis in Mycobacterium intracellularis lung disease group was significantly higher than that in Mycobacterial abscesses lung disease group (χ2＝23.888, P＜0.01).There was no significant difference in the 28-day mortality rate between the two groups (χ2＝3.244, P＞0.05), while the survival rate in patients with Mycobacterium intracellularis lung disease within 120 days was significantly higher than that in patients with Mycobacterial abscesses lung disease (χ2＝12.780, P＜0.01).Conclusion When critically ill patients are positive for acid-fast staining, the ICU physician should consider the possibility of NTM lung disease.For severe patients with long-term mechanical ventilation , Mycobacterium abscessus infection should be considered first.

Establishment and application of DPO-based quadruple real-time PCR for detection of mycobacteria / 中华检验医学杂志

Objective To establish a rapid,accurate and specific method to detect the common mycobacteria based on multiplex real-time PCR.Methods The dual priming oligonucleotide ( DPO)primers and TaqMan probes labeled with FAM,ROX,HEX or JOE fluoresceins at 5' end and eclipse at 3' end respectively were designed to detect the 16S rRNA of mycobacteria.Both specificity and sensitivity were estimated on multiplex real-time PCR detecting genome DNA from 4 mycobacterial model species.Sixty eight early morning sputum specimens collected from hospitalized patients in the Red Cross Hospital of Hangzhou were detected by multiplex real-time PCR,bacterial culture and smear microscopy simultaneously.The positive rates were analyzed by chi-square.Results Mycobacteria including Mycobacterium tuberculosis and three common non-tuberculosis mycobacteria spp.were identified by multiplex real-time PCR accurately and specifically,with the limited load at 101 cfu/ml.In 68 sputum specimens,31 were positive (positive rate 45.6％ ) by this method,which was significant higher than that by smear microscopy ( positive rate 14.7％,x2 =15.4,P ＜0.05 ).The positive cases were identified as 28 Mycobacterium tuberculosis,1 Mycobacterium avium and 2 Mycobacterium intracellulare in agreement with the culture results.One case,which is detected by culture,but not by PCR,was identified as Mycobacterium chelonae by sequencing.Conclusion The multiplex real-time PCR characterizing as sensitive,specific and time-saving for Mycobacterium tuberculosis and common non-tuberculosis mycobacteria could be chosen as the rapid laboratory test of mycobacterial infection.

Detection of streptomycin-resistance associated rpsL and rrs gene mutations in Mycobacterium tuberculosis by PCR-single-strand-conformational polymorphism / 中华临床感染病杂志

ObjectiveTo establish a novel rapid detection method based on PCR-single-strand-conformational polymorphism (PCR-SSCP) to determine mutation of streptomycin-resistance associated rpsL and rrs genes in isolates of Mycobacterium tuberculosis (MTB).MethodsStreptomycin-resistance of 112 MTB isolates was detected using the routine drug susceptibility test,and a special PCR-SSCP assay was established.The mutations of rpsL and rrs genes in streptomycin-resistant MTB isolates were detected by PCR-SSCP and PCR direct sequencing (PCR-DS) ; the results from two techniques were compared.Results All isolates had both rpsL and rrs genes.Fifty-two isolates (46.4％) were streptomycin susceptible,in which only 1 isolate showed abnormal PCR-SSCP fragments from rrs gene,and the specificity of PCR-SSCP was 98.1％ (51/52).Sixty isolates (53.6％) were streptomycin-resistant,in which 46 (76.6％) and 11 ( 18.3％ ) isolates presented the abnormal PCR-SSCP fragments of rpsL and rrs gene,respectively.One streptomycin-resistant isolate showed abnormal PCR-SSCP fragments from both rpsL and rrs genes.The sensitivity of PCR-SSCP was 93.3％ (56/60).ConclusionThe PCR-SSCP that established in this study is a specific and sensitive method for rapid detection of the streptomycin-resistance associated mutations in rpsL and rrs genes of MTB.

Phalanx-Lengthening Method in the Treatment of Amputated Fingers / 第二军医大学学报

79 cases (180 amputated fingers) underwent gradual distraction through phanlanges. The bone elongation obtained varied from 1 to 3.2 cm, with an average of 2.2 cm. Finger stumps were examined by measurement of 2 point discrimination (2PD) and sensative nerve conduction velocity as well as SO, both before and post lengthening. We confirmed that it was safe to distract the finger stump at a daily rate of 1 mm. Several fingers can be lengthened simultaneously using our device. The adjacent joint was also stretched other than compressed. Therefore, the lateral accessory ligament contraction and joint crush injury were avoided. The long-term length increase was maintained by subperiosteal osteotomy. Gradual finger lengthening is a simple, safe and effective method.

The Effects of Tibia Lengthening on the Histomorphology of Tibial Nerve in Rabbits / 第二军医大学学报

The effects of gradual tibia lengthening at different speeds on the histomorphology of tibial nerve were studied in 30 rabbits by self-made external distraction device. It was showed that the leg was tracted at the speed of 1 mm/d, the tibial nerve was lengthened correspondingly. Gradual stress could stimulate the growth of nervous tissue and no nervous functional and constructural injuries were found When the leg was distracted at the speed of 2 mm/d, limb elongation within 40% was safe, otherwise, severe nervous damage would occur.