ObjectiveTo learn the rpoB mutation difference in rifampicin/rifabutin cross-resistant (RIF/Rfb-R)clinical isolates and in rifampicin-resistant/rifabutin-susceptible (RIF-R/Rbo-S)clinical isolates of Mycobacterium tuberculosis.Methods To sequence the full-length genome of rpoB gene,and analyze the rpoB full-length gene mutation differences in 278 RIF/Rfb-R clinical isolates,40 RIF-R/Rfb-S clinical isolates,30 rifampicin-susceptible/rifabutin-susceptible (RIF-S/Rfb-S) and in 1 reference strain ofH37Rv.ResultsNo mutations of rpoB full-length gene were found in H37Rv reference strain and RIF-S/Rfb-S clinical isolates.In RIF/Rfb-R clinical isolates,531 (70.5％ ) and 526 (20.9％ ) were the most frequent mutation codons.223 (80.2％ ) isolates possesed single mutations as S531L,S531W,H526D,H526Y,H526R,Q513K,Q513P,Q510H,V176F,P287R,Y395C and H404Y.55 (19.8％) isolates had multiple mutations,and among these the S531L,H526 R,H526Y,H526D,D516G and Q513K were the main substitutions which were in combination with other points.In RIF-R/Rfb-S clinical isolates,516 (65.0％),526 ( 17.5％ ) and 533 ( 10.0％ ) were the most frequent mutation codons.21 (52.5％ ) isolates possesed single mutations as L533P,H526L,H526S,S522L,D516V,D516Y and D516F.19 (47.5％)isolates had multiple mutations and among these the D516V and L533P were the main substitutions which were in combination with other points.CondusionsIn our study,100％ rifamycin-resistant clinical isolates of Mycobacterium tuberculosis had rpoB mutations,but the mutations in RIF/Rfb-R clinical isolates were sharply different from RIF-R/Rfb-S clinical isolates in mutation positions or amino acids substitutions of single mutations strains,mutation positions or combination types and the most frequently mutation codons or amino acids substitutions of multiple mutations strains.Thus,DNA sequencing is instructive and meaningful to choose rifampicin or rifabutin for tuberculosis treatment.

OBJECTIVE To understand nosocomial candidal infection among tuberculosis patients and its drug(sensitivity).(METHODS) Totally 6280 clinical samples from Jan 2002 to Dec 2004 were cultured;and part of(positive) ones were tested their drug sensitivity to FC,FLC,KET and ITC.RESULTS From all cultured samples 2767 Candida strains(positive rate was 44.06%) were isolated.From them C.albicans,C.glabrata,C.tropicalis,C.krusei and other Candida were 2006, 344,206,95 and 116 strains,their positive rate was 31.94%,(5.48%),3.28%, 1.51% and 1.85%,respectively.Their drug sensitivity rate to four drugs were as follows: to FC was 93.73%,to TTC 62.76%,to FLC 51.03% and to KET was 47.59%. CONCLUSIONS The condition of(tuberculosis) patient would become serious due to higher dual infection rate by Candida after too long anti-(tuberculosis) treatment.Among the four kinds of drugs the FC has the best anti-candidal activity.

Objective To study the clinical value of simultaneous amplification and testing for detection of Mycobacteria tuberculosis(SAT-TB)in sputum samples and bronchoalveolar lavage fluid(BALF)samples. Methods Totally 169 sputum samples and 151 BALF samples from suspected pulmonary tuberculosis patients were detected by both SAT and Bactec MGIT960.The sensitivity,specificity,positive predictive value(PPV)and negative predictive value(NPV)of the samples using SAT-TB were calculated. Results Taken the results of BD960 as the reference,the sensitivity,specificity,PPV and NPV using SAT-TB of sputum samples were 84.00% (42/50),93.06%(67/72),89.36%(42/47)and 89.33%(67/75)respectively;and those of BALF samples 89.19% (33/37),95.12%(39/41),94.29%(33/35)and 42.39%(39/92)respectively.Taken clinical diagnostic results as reference standard,the sensitivity,specificity,PPV and NPV using SAT-TB of the sputum samples were 57.73% (56/97),93.06%(67/72),91.80%(56/61),and 62.04%(67/108)respectively;and those of BALF samples 51.82%(57/110),94.29%(39/41),96.61%(57/59)and、42.39%(39/92)respectively.The sensitivity,specificity, PPV and NPV using BD960 of the sputum samples were 51.55%(50/97),95.83%(69/72),94.34%(50/53),and 59.48%(69/116)respectively;and those of BALF samples 33.64%(37/110),90.24%(37/41),90.24%(37/41) and 33.64%(37/110)respectively.Conclusion SAT-TB is a rapid and sensitive method for the detection of Myco-bacteria tuberculosis in sputum and BALF samples.It can improve the detection rate of mycobaterium tuberculosis.

Objective To analyze the clinical characteristics of pulmonary tuberculosis patients compli-cated with infection of Nocardia farcinica aiming to improve the diagnosis and treatment the disease.Methods The clinical data of 22 cases of pulmonary tuberculosis complicated with Nocardia farcinica infection admitted to Guang-zhou Chest Hospital from June 2020 to December 2023 were collected and the clinical manifestations,imaging,laboratory tests,treatment process,and disease outcomes were retrospectively analyzed.Results Among the 22 patients,there were 13 males and 9 females,aged 20～86 years,with a median age of 52 years.Common clinical manifestations included cough(22/22),sputum(21/22),and underlying diseases(13/22).One case was positive for cerebrospinal fluid culture,and 21 cases were positive for sputum culture.The culture period was 5～26 days,with a median culture period of 18 days.The imaging manifestations were mainly plaques,plaques and cavities,and the lesions were spread in both lungs(17/22)and cavities(11/22).After anti-tuberculosis treatment,the absorption of lung lesions in some patients was poor,and the absorption of the lesions was improved after anti-nocardia treat-ment.8 cases were cured,13 cases were improved and 1 case died.Conclusion The clinical symptoms of pa-tients with pulmonary tuberculosis complicated with Nocardia farcinica were atypical,the culture period of Nocardia was long,and the imaging manifestations were similar to pulmonary tuberculosis,which is prone to misdiagnosis and missed diagnosis.For patients with poor response to anti-tuberculosis treatment and slow lesion absorption,the possi-bility of a concurrent Nocardia infection should be considered.