Effects of the multiplex PCR kit for diagnosis of tuberculosis

Background: Facing urgent requirements of the rapid diagnosis of tuberculosis nowadays, our laboratory have improved the multiple PCR for 3 target genes spontaneously (IS 1081, IS 6110, 23S rDNA) and developed into the multiplex PCR kit to improve the effects of diagnosis of tuberculosis. Objective: To evaluate the multiplex PCR kit for the 3 target genes (IS 1081, IS 6110, 23S rDNA) for the diagnosis of tuberculosis on standard panel and clinical specimens. Subjects and method: DNA extracted from M. tuberculosis strains and clinical specimens were amplified by multiplex PCR kit, comparison with singleplex PCR for each target gene. Results: On standard panel, sensitivity and specificity reached 100% and detected limitation was 100 fg DNA template (about 3 M. tuberculosis cells). Multiplex PCR kit detected 195/307 (63.52%) suspected clinical specimens compared with singleplex PCR which detected 106/307 (34.53%) for IS 1081, 182/307 (59.82%) for IS 6110 and 136/307 (44.30%) for 23S rDNA. Conclusions: PCR amplification with one target gene was insufficient for diagnosis of the tuberculosis strains in Viet Nam. Multiplex PCR kit for 3 target genes simultaneously (IS 1081, IS 6110, 23S rDNA) could detect all tuberculosis strains.

rpoB Gene Mutations in Rifampicin - Resistant Mycobacterium Tuberculosis Strains in Vietnam

Introduction: Mycobacterium tuberculosis resists rifampicin (RIF) because of mutations in the rpoB (the p subunit of RNA polymerase) gene, mostly in the 81 bp region. \r\n', u'Objectives: Identify the frequency and characteristics relative to drug - resistant rpoB gene mutation in RIF - resistant M. tuberculosis strains. \r\n', u'Subjects and method: 40 M. tuberculosis strains including 11 RIF - sensitive strains and 29 RIF - resistant strains. Some bio molecular techniques were used such as extracting mycobacterial DNA, PCR, cloning, sequencing and analyzing mutation related RIF - resistance on rpoB gene. \r\n', u'Results: No mutation was found on the 81 bp region of rpoB gene of the RIF - sensitive M. tuberculosis strains. The rate of mutation on rpoB gene of 29 RIF - resistant M. tuberculosis strains is 96.6%. We found 12 mutation codon positions on the 81 bp region of the rpoB gene, and the mutation codon positions with high frequency were 531 (51.7%) and 526 (31%). The mutation position found in only one strain is codon 519 (3.4%) but not found in other reports. There are 15 types of drug resistant mutations in which TCG531 TCG is the most common with 50%. Multi - drug resistance was seen in mutable and none mutable cases, with all codon positions and mutable forms. \r\n', u'Conclusion: No mutation was found on the 81 bp region of the rpoB gene of RtF - sensitive M. tuberculosis strains. The rate of mutation on the rpoB gene of RIF - resistant M. tuberculosis strains is 96.6%. The new mutation position found is codon 519. The mutation on the rpoB gene does not determine the multi - drug resistance of M. tuberculosis. \r\n', u'

Incidence of H. pylori infection in gastroduodenal ulcer patients

To study the proportion of H. pylori infection in classes of patients with gastroduodenal ulcer, 4 methods were used simultaneously: culture, urease test, Gram stain and histology. The results found that the proportion of H. pylori infection is highest in duodenal ulcer or duodenal ulcer combining with gastritis, gastric ulcer combining with duodenitis (91.7% - 100%). In gastric ulcer or gastritis only, the positive proportion is 54-65% by culture, 54-56% by urease test, 63-82% by Gram stain, 37-52% by histology

An outbreak of typhoid fever in a soldier camp

There were 296 cases of typhoid fever of which 52 cases admitted in hospital and no death happened in a training camp for new soldiers in 55 days outbreak. Investigated the outbreak situation at local health station and outbreak area: house, dining room, kitchen, canteen, toilet, resources of water, dung and waste. The improper dung management caused environmental pollution was the main cause of outbreak. Clinical condition was a typical and treated by common and special antibiotics had good results.

Treatment of bone fracture in children by the metaizeau’s flexible wire

Fracture of the shaft of femur and tibia in children aged from 4 to 17 sometimes caused the problem in reduction and immobilization and needed an osteosynthesis. Among the internal fixation procedures, intramedullary nailing by using Metaizeau’s flexible wire under C-arm control showed the best way and the best choice. 30 fractures of the shaft of femur and tibia failed in conservative treatment have been operated by above methods with successful results since Jan-1996 to February-2000 in Saint-Paul hospital. The advantages of the method were noted as no opening fracture focus, no bleeding, no risk of infection, short stay in hospital and no need of cast immobilization. So patients will come back soon to theirs activities and school.