BACKGROUND: In hepatocellular carcinoma (HCC), the frequency of p53 mutation and the association with hepatitis B virus (HBV) infection varies with geographic locations and risk factors. The aim of this study was to determine the frequency of codon 249 mutation of p53, p53 overexpression, and HBV DNA positivity and to observe the relationship between them in Korean HCC. METHODS: We analyzed overexpression of p53 in hepatoma tissue from 17 HCC patients by immunohistochemistry (IHC), specific mutations at the third base position of codon 249 by PCR-restriction fragment length polymorphism (PCR-RFLP) method, and presence of HBV by nested PCR. RESULTS: Although a point mutation at codon 250 was seen in one (5.8%) of 17 patients, no codon 249 mutations were found in the patient cohort. The p53 protein was overexpressed in 4 (23.5%) of 17 HCCs. PCR for HBV DNA from HCCs showed a positivity rate of 82.4% (14 of 17 specimens). CONCLUSION: In HCC of this study, HBV infection was not associated with either 249 mutation or overexpression of p53, and overexpression of p53 protein seemed to be related to other than this mutation.
Carcinoma, Hepatocellular* ; Codon* ; Cohort Studies ; DNA ; Geographic Locations ; Hepatitis B virus* ; Hepatitis B* ; Hepatitis* ; Humans ; Immunohistochemistry ; Point Mutation ; Polymerase Chain Reaction ; Risk Factors

BACKGROUND: We evaluated the performance of a newly developed real-time polymerase chain reaction (PCR) method using TaqMan probe (TP) and internal control (IC) for quantitation of BK virus (BKV) DNA. METHODS: PCR primers and TP were targeted for the VP1 of BKV and 300 bp-region of VP1 was cloned to prepare a standard DNA. Threshold cycles (Ct) of IC was set at 33+/-3. The recovery rates, precision, linearity, and limit of detection (LOD) were measured using the standard DNA. To correlate TP with previous hybridization probe (HP) method, Ct of those were compared using 35 HP-positive and 15 HP-negative specimens, and the interpretation agreement was analyzed in 63 consecutive clinical specimens including 32 urines and 31 plasmas. Fifty-three53 specimens measured for IC were analyzed for positive rates and levels of BKV according to Ct of IC. RESULTS: The average recovery rate was 101.1% and intra-assay and inter-assay coefficiency variations were 0.017~0.059 and 0.036, respectively, with the specimens of 3 log/mL, and 0.041~0.063 and 0.045, respectively, with the specimens of 6 log/mL. LOD was 183 copies/mL and linearity range was 2.7 log- 12 log/mL. Ct of TP were correlated with those of HP with the function of y=0.8912x+0.3164 (R2=0.9062). Among 63 clinical specimens, 16 were positive in TP and 12 were positive in HP with an agreement of 90.4%. Ct of IC were over 36 in 31 specimens (22 urines and 9 plasmas), of which BKV DNA was much higher in 7 (22.5%) BKV-positive specimens (5.9+/-1.7 log/mL) than in 4 (18.1%) BKV-positive specimens (3.9+/-1.0 log/mL) of 22 having Ct of IC < or =36.; 5.9+/-1.7 vs. 3.9+/-1.0 log/mL. CONCLUSION: TP warrants to be a reliable method for quantification of BKV. IC seemed to be essential to differentiate false-negative results or underestimation of BKV in clinical specimens, especially in urine.
BK Virus* ; Clone Cells ; DNA* ; Limit of Detection ; Plasma ; Polymerase Chain Reaction ; Real-Time Polymerase Chain Reaction*

BACKGROUND: The isolation of nontuberculous mycobacteria (NTM) has been increasing worldwide as well as its clinical importance. The aim of this study was to investigate the distribution and clinical significance of NTM that has been isolated from respiratory specimens during a recent two-year period at a tertiary hospital. METHODS: We analyzed respiratory samples that were obtained between January 2009 and December 2010 for AFB culture. We retrospectively reviewed the electronic medical records of these patients to obtain both clinical and radiologic information. NTM pulmonary disease was defined by using the guidelines provided by the America Thoracic Society/Infectious Diseases Society of America. RESULTS: Among the 1,601 specimens that resulted in a positive AFB culture, 310 (19.4%) were NTM. In 189 patients, the most common isolate was M. avium-intracellulare complex (MAC) (127, 67.2%), which was then followed by M. abscessus (31, 16.4%), M. fortuitum (10, 5.3%), M. kansasii (9, 4.8%), and other NTM species. Of these, 93 (49.2%) patients were diagnosed with NTM pulmonary disease. MAC, M. abscessus, and M. kansasii were more virulent than the other species. None of the cases of NTM pulmonary disease were caused by M. fortuitum, M. chelonae, M. peregrinum, M. terrae complex, or M. gordonae. CONCLUSION: In Korea, the prevalence of NTM isolates is increasing, as are the cases of pulmonary disease. The pathogenic potential of NTM differs enormously by species and as a result the treatment of NTM lung disease depends on which species has caused the infection. The isolation and identification of NTM isolated from respiratory specimens are mandatory in order for clinical microbiology laboratories to make an accurate diagnosis and suggest the proper treatment of the NTM disease.
Americas ; Electronic Health Records ; Humans ; Korea ; Lung Diseases ; Nontuberculous Mycobacteria ; Prevalence ; Retrospective Studies

BACKGROUND: The aim of the present study was to investigate the epidemiologic characteristics of extrapulmonary tuberculosis (EPTB) in Korea. In addition, the results of culture-confirmed (CC) EPTB were compared with those of clinically-diagnosed (CD) EPTB. METHODS: We retrospectively reviewed non-duplicate data of tuberculosis from the Samsung Medical Center from 1995 to 2010. A total of 6,249 and 38,726 cases of tuberculosis were CC and CD EPTB cases, respectively. The cases were categorized according to the type of specimen or by the clinically-affected sites. RESULTS: The proportions of EPTB among all tuberculosis cases were 12% (745/6,249) and 22% (8,608/38,726) of the CC and CD cases, respectively. The distribution of both age and gender between pulmonary tuberculosis (PTB) and EPTB cases were significantly different (P<0.001). The most common types of EPTB were tuberculous lymphadenitis, pleural TB, and abdominal TB. Pleural involvement was more common in males, while lymph node involvement was observed more frequently in females in both the CC and CD cases (M/F ratio in regards to pleura were 1.63 and 2.08, while M/F ratio in regards to the lymph node were 0.46 and 0.54). CONCLUSION: The dataset of EPTB cases in Korea was first evaluated over a 16-year period and compared the cases of CC EPTB to those of CD EPTB. The epidemiologic characteristics of EPTB were different from that of PTB as well as the EPTB of other countries. The present study might provide useful information regarding the epidemiology of EPTB in Korea and other countries.
Female ; Humans ; Korea ; Lymph Nodes ; Male ; Pleura ; Retrospective Studies ; Tuberculosis ; Tuberculosis, Lymph Node ; Tuberculosis, Pulmonary

BACKGROUND: Clostridium difficile is the main etiologic agent of antibiotic-associated diarrhea and the most common cause of hospital-acquired diarrhea. Recently, the incidence of C. difficile infections (CDI) has increased and new highly virulent C. difficile strains have emerged. Therefore, accurate and rapid diagnosis is needed. We compared the results of using chromID C. difficile (chromID CD, bioMerieux, France) with the conventional C. difficile Selective Agar (CDSA; BD, USA) for the isolation of C. difficile. METHODS: A total of 738 stool specimens of suspected CDI patients at the Severance Hospital from July to August 2011 were inoculated onto CDSA. Among them, 104 stool specimens revealed colonies on CDSA that were then re-inoculated onto chromID CD. The stool samples were stored at -20degrees C until the time of the re-inoculation. Cultured agars were interpreted after 24 hrs and 48 hrs, respectively. Species identification was performed on the basis of colony characteristics on agar plates as well as the ATB 32A system (API System SA, France). RESULTS: The recovery rates of CDSA and chromID CD were 30.1% and 77.5% after 24 hrs, and 77.5% and 98.6% after 48 hrs, respectively. All of the C. difficile isolates were recovered as typical gray/black colonies on chromID CD. CONCLUSION: The performance of chromID CD for the isolation of C. difficile was better than that of conventional CDSA. The chromID CD could provide easy and sensitive detection of C. difficile even after 24hrs of incubation.
Agar ; Clostridium ; Clostridium difficile ; Diarrhea ; Humans ; Incidence

The three components of taxonomy are classification, nomenclature and identification. Traditionally, bacterial classification and identification were performed based on the morphology and the biochemical data of the bacteria. In newer theories, or so-called natural concepts, the relationships between bacteria are based on the overall similarities of both the phenotypic and genotypic characteristics. The polyphasic taxonomy, or current taxonomy, describes the integration of all of the available genotypic, phenotypic, and phylogenetic information into a consensus type of general-purpose classification. When routine identification methods that are based on the biochemical tests fail, alternative procedures such as complete 16s rRNA gene sequence analysis are required. Although the results of 16s rRNA gene sequence analysis have not been fully discriminatory to differentiate closely related species, they may guide the additional analyses that are required for species identification.
Bacteria ; Consensus ; Genes, rRNA ; Sequence Analysis

A 60-year-old male with continuous ambulatory peritoneal dialysis was admitted because of abdominal discomfort and turbid dialysate. He had a history of chronic renal failure due to diabetic nephropathy. His WBC count of perpheral blood was 8,500/mm3 (neutrophil 92%), and that of dialysate was 1,400/mm3 (polymorphonuclear leukocyte 69%, lymphocyte 31%). Pure growth of Leclercia adecarboxylata was isolated from dialysate. The L. adecarboxylata isolate was susceptible to ampicillin, ampicillin/sulbactam, cephalothin, cefoperazone, cefoxitin, cefotaxime, ceftazidime, aztreonam, imipenem, gentamicin, tobramycin, amikacin, tetracycline, trimethoprim- sulfamethoxazole and ciprofloxacin. Cephalothin & amikacin were added into dialysate, and his clinical symptoms and turbidity of dialysate were resolved. L. adecarboxylata has been rarely isolated from clinical specimens. To our knowledge, this is the first report of L. adecarboxylata isolated from clinical specimen in Korea. On review of the world literature, we found only 7 cases of L. adecarboxylata infections. This microorganism has been isolated from lower extremity wounds and sputum as part of a mixed flora in 3 cases and 1 case, respectively, but it was the only microorganism isolated from cultures of blood in 3 cases. These 3 patients with bacteremia due to L. adecarboxylata had severe underlying diseases, and clinical symptoms were developed after invasive procedures. All of the L. adecarboxylata isolates from clinical specimens were susceptible to antimicrobial agents tested, and the responses to antibiotic therapy were excellent. It is difficult to identify this organism because its biochemical reactions are similar to those of Escherichia coli, therefore careful identification is required. And additional studies are necessary to determine the pathogenic potential and route of infection of this organism.
Amikacin ; Ampicillin ; Anti-Infective Agents ; Aztreonam ; Bacteremia ; Cefoperazone ; Cefotaxime ; Cefoxitin ; Ceftazidime ; Cephalothin ; Ciprofloxacin ; Diabetic Nephropathies ; Enterobacteriaceae* ; Escherichia coli ; Gentamicins ; Humans ; Imipenem ; Kidney Failure, Chronic ; Korea ; Leukocytes ; Lower Extremity ; Lymphocytes ; Male ; Middle Aged ; Peritoneal Dialysis, Continuous Ambulatory* ; Sputum ; Sulfamethoxazole ; Tetracycline ; Tobramycin ; Wounds and Injuries

The group A streptococcus is capable of producing exotoxins that have been linked to a toxic shock-like syndrome. Streptococcal toxic shock syndrome is a rapidly progressive associated with injury to multiple organ systems and a 30-60% mortality rate. These cases are very rare in Korea. We present a case of 32-year-old prenant woman who developed streptococcal toxic shock syndrome following intrauterine fetal death. She manifestated hypotension, shock, increased level of creatinine, disseminated intravascular coagulopathy, liver impairment, renal failure, pulmonary edema and adult respiratory distress syndrome. Blood cultures yielded Streptococcus pyogenes. After 17 hours on admission, she died in spite of massive transfusion, antibiotics therapy and ventilatory support. Clinicians should be alert to the importance of early diagnosis and treatment of this lethal infection.
Adult ; Anti-Bacterial Agents ; Creatinine ; Early Diagnosis ; Exotoxins ; Female ; Fetal Death* ; Humans ; Hypotension ; Korea ; Liver ; Mortality ; Pulmonary Edema ; Renal Insufficiency ; Respiratory Distress Syndrome, Adult ; Shock ; Shock, Septic* ; Streptococcus ; Streptococcus pyogenes

The major cause of pseudomembranous colitis is known to be Clostridium difficile (C. difficile). There are few reports that Clostridium species other than C. difficile has caused pseudomembranous colitis. We report a case of pseudomembranous colitis caused by clostridium glycolicum(C. glycolicum). A 47-year-old woman who had operational history for rectal cancer 3 months ago, was readmitted with diarrhea of 3 days duration. Seven weeks before admission, she had received ornidazole and ceftriaxone due to diarrhea and abdominal pain, and her symptoms were improved. She had received additional radiation therapy for rectal cancer during six weeks before the recent onset of diarrhea. On admission, she complained of watery diarrhea ten times a day and abdominal pain. She had tenderness on both lower abdomen. Pseudomembrane was observed by colonoscopic and histologic examination. VIDAS C. difficile toxin A II assay was positive and C. glycolicum was isolated in the stool. She recovered after receiving oral metronidazole treatment.
Abdomen ; Abdominal Pain ; Ceftriaxone ; Clostridium difficile ; Clostridium* ; Diarrhea ; Enterocolitis, Pseudomembranous* ; Female ; Humans ; Metronidazole ; Middle Aged ; Ornidazole ; Rectal Neoplasms

BACKGROUND: Continuous monitoring blood culture systems (CMBCS) reduce the time and false negative rates of bacterial growth compared with the traditional manual blood culture systems which have been used in many hospitals yet. The purpose of this study is to evaluate the terminal subcultures monitored by Vital system compared with the manual system and to determine the guideline of terminal subcultures. METHODS: A retrospective study was conducted over a period of one year (from January to December 1995) with manual blood culture system and and sixteen months (from February 1996 to May 1997) with Vital system. All of the positive and negative blood bottles were done Gram staining and subcultured aerobically and anaerobically with 7-day terminal subculture protocol. All of the isolates were identified with API systems or ATB systems. RESULTS: Among 3,344 cases with the manual system, 305 cases (9.1%) were declared positive and 424 cases (8.8%) out of 4,822 cases with Vital system were positve. The terminal subcultures detected 48 cases (1.44%) in manual system and 9 cases (0.19%) in Vital system according to 7-day protocol. No statistical differences were observed in results among 5 day, 7 day and terminal subcultures. Those of false negative organisms were gram positive cocci (22 cases), Enterobacteriaceae (13 cases), non-fermenters (12 cases) and gram positive rod (1 case) with the manual system and gram positive cocci (4 cases), Entrobacteriaceae (1 case), non-fermenter (1 case) and yeasts (3 cases) with Vital system. CONCLUSIONS: These results suggest that terminal subculture of Vital systemnegative blood culture bottles is not necessary except S. aureus and fungus bacteremia on the basis of clinical situation.
Bacteremia ; Enterobacteriaceae ; Fungi ; Gram-Positive Cocci ; Retrospective Studies ; Yeasts