Molecular Genetic Typing of Legionella pneumophila Strains Isolated in Jejudo, Korea

Twenty two strains of Legionella species isolated from Jejudo, Korea were identified by comparing the rpoB (300 bp), dotA (360 bp), and mip (396 bp) gene sequence analysis. Furthermore, their genotypes were determined by sequence analysis of rpoB/dotA subgroup typing, pulse-field gel electrophoresis (PFGE) and random amplified polymorphic DNA (RAPD) patterns. Of the 22 isolates, 21 strains were identified as L. pneumophila and 1 strain was close to L. erythra (>95% similarity of rpoB and mip). Most of the L. pneumophila strains (90%) belonged to P-I of rpoB/dotA subgroup typing, one strain of each P-III and P-IV. L. pneumophila isolates were further grouped into 4 and 6 different PFGE (P1 to P4) and RAPD (R1 to R6) patterns, respectively. On the basis of these genotypes, which may be useful for future epidemiological studies, existence of diverse L. pneumophilla population in Jejudo, Korea were observed.

Mutations of katG and inhA in MDR M. tuberculosis / 결핵및호흡기질환

BACKGROUNDS: Mutations of katG and inhA (ORF and promoter) are known to be related to isoniazid (INH) resistance of Mycobacterium tuberculosis. Because reports on these mutations in Korean isolates are limited (i.e. only the frequency of katG codon 463 was evaluated.), we tried to know the kinds of mutations of two genes and their frequencies in INH resistant Korean M. tuberculosis strains. METHODS: PCR was performed to amplify katG (2,223 bp), inhA ORF (-77~897, 975 bp), and inhA promoter (-168~80, 248 bp) from 29 multidrug resistant M. tuberculosis (MDR-TB) DNAs prepared by bead beater-phenol method. Their sequences were determined and analyzed by ABI PRISM 3730 XL Analyzer and MegAlign package program, respectively. RESULTS: All of the isolates had more than one mutation in katG or inhA gene. Twenty seven (93%) of 29 tested strains had katG mutations, which suggests that katG is a critical gene determining INH resistance of M. tuberculosis. Amino acid substitutions, such as Arg463Leu and Ser315Thr, due to point mutations of the katG were the most frequent (62.1% and 55.2%) mutations. In addition, deletion of the katG gene was frequently observed (17.2%). Analyzed Korean MDR-TB isolates also had variable inhA mutations. Point mutation of inhA promoter region, such as -15 (C-->T) was frequently found. Substitution of amino acid (Lsy8Asn) due to point mutation (AAA-->AAC) of inhA ORF was found in 1 isolate. Interestingly, 14 point mutated types that were not previously reported were newly found. While four types resulted in amino acid change, the others were silent mutations. CONCLUSIONS: Although it is not clear that the relationship of these newly found mutations with INH resistance, they show marked diversity in Korean MDR-TB strains. It also suggests their feasibility as a molecular target to supplement determining the INH resistance of clinical isolates because of the possible existence of low-level INH resistant strains.

Mutations of katG and inhA in MDR M. tuberculosis / 결핵및호흡기질환

BACKGROUNDS: Mutations of katG and inhA (ORF and promoter) are known to be related to isoniazid (INH) resistance of Mycobacterium tuberculosis. Because reports on these mutations in Korean isolates are limited (i.e. only the frequency of katG codon 463 was evaluated.), we tried to know the kinds of mutations of two genes and their frequencies in INH resistant Korean M. tuberculosis strains. METHODS: PCR was performed to amplify katG (2,223 bp), inhA ORF (-77~897, 975 bp), and inhA promoter (-168~80, 248 bp) from 29 multidrug resistant M. tuberculosis (MDR-TB) DNAs prepared by bead beater-phenol method. Their sequences were determined and analyzed by ABI PRISM 3730 XL Analyzer and MegAlign package program, respectively. RESULTS: All of the isolates had more than one mutation in katG or inhA gene. Twenty seven (93%) of 29 tested strains had katG mutations, which suggests that katG is a critical gene determining INH resistance of M. tuberculosis. Amino acid substitutions, such as Arg463Leu and Ser315Thr, due to point mutations of the katG were the most frequent (62.1% and 55.2%) mutations. In addition, deletion of the katG gene was frequently observed (17.2%). Analyzed Korean MDR-TB isolates also had variable inhA mutations. Point mutation of inhA promoter region, such as -15 (C-->T) was frequently found. Substitution of amino acid (Lsy8Asn) due to point mutation (AAA-->AAC) of inhA ORF was found in 1 isolate. Interestingly, 14 point mutated types that were not previously reported were newly found. While four types resulted in amino acid change, the others were silent mutations. CONCLUSIONS: Although it is not clear that the relationship of these newly found mutations with INH resistance, they show marked diversity in Korean MDR-TB strains. It also suggests their feasibility as a molecular target to supplement determining the INH resistance of clinical isolates because of the possible existence of low-level INH resistant strains.

A Case of Acute Alcoholic Myopathy with Paraparesis and Myoglobinuric Renal Failure

Acute alcoholic myopathy presented with paraparesis, myoglobinuria. And acute renal failure is an uncommon complication of alcoholism. A 34-year-old man had been a heavy alcohol drinker for a year, complained of sudden lower extremity weal; ness and swelling after heavy drinking. On examination, lower extremity was swollen and unable to move. Laboratory data showed markedly elevated GOT, LDH, CK, and myoglobinuria. Initial electrodiagnostic study was indefinite for diagnosis of myopathy and biopsy of the quadriceps muscle showed slight increased eosinophilia of sarcoplasm. But in followup study, myopathic findings and degeneration becarne apparent in electromyography and blopsy.