Sun Min Lee, Kyung Jun Kim, Chulhun L. Chang
Ann Clin Microbiol 2018 September, 21(3): 47-50. Published on 20 September 2018.
Background: A simple and cost-effective method is needed for the detection of rifampicin resistance in Mycobacterium tuberculosis in resource-limited settings. We suggest a broth medium-based method using 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride (STC) for detection of rifampin resistance of tubercle bacilli within a reasonable time frame.
Methods: The type strain (M. tuberculosis H37Rv) and 45 cultured clinical strains of M. tuberculosis (35 rifampin-susceptible and 10 rifampin-resistant) were used. Phenotypes of rifampicin resistance were tested by the Korea Institute of Tuberculosis, and confirmed by GenoType MTBDRplus (Hain Lifescience, Germany). Susceptibility tests were performed using STC-containing OADC-enriched Middlebrook 7H9 broth (BD, USA).
Results: All tests were finished in 3 to 6 days. The same results were obtained with the standard and current methods for all 45 clinical isolates (100% sensitivity and specificity for resistance detection).
Conclusion: The current method using STC is a good alternative for detecting M. tuberculosis rifampin resistance in a cost-effective and timely fashion, which is particularly important in resource-limited settings.
Jong-Mi Lee, Mi Jung Park, Woong Heo, Kang Gyun Park, Yong Gyu Park, Seung Beom Han, Young-Seok Cho, Yeon-Joon Park
Ann Clin Microbiol 2018 September, 21(3): 51-57. Published on 20 September 2018.
Background: Gastrointestinal (GI) bleeding can result from various conditions, including ulcers, neoplasms and infectious enterocolitis. The aim of this study was to evaluate the utility of the fecal immunochemical transferrin test compared with the fecal Hb test in various clinical settings.
Methods: A total of 1,116 clinical stool specimens submitted for fecal occult blood testing were prospectively examined using both FIT Hb and FIT Tf kits (AlfresaPharma, Japan). To verify the specificity of the two tests, stool specimens from 265 health check-up examinees were also included.
Results: A review of medical records revealed that 396 patients had clinical conditions associated with GI bleeding. FIT Hb and FIT Tf results were positive in 156 (39.4%) and 137 (34.6%) cases, respectively, and an additional 194 (49.0%) cases tested positive with either FIT Hb or FIT Tf. The two tests showed a moderate strength of agreement (kappa value; 0.56). Colitis (n=71) was associated with the most GI bleedings, followed by acute gastroenteritis (n=29), GI ulcers (n=27) and GI cancers (n=15). While the first two groups had higher positive rates on FIT Tf, patients in the latter two groups had higher positive rates on FIT Hb. Notably, four of nine specimens from premature babies tested positive only on FIT Tf. The specificity of FIT Hb and FIT Tf was 100% and 99.6%, respectively.
Conclusion: Concurrent use of FIT Hb and FIT Tf improved the detection rate of occult GI bleeding, especially in patients with infectious GI disease (such as colitis or gastroenteritis) and in premature babies.
Heungsup Sung, Mi-Na Kim, Dongeun Yong, Miae Lee, Jongwook Lee, Mi-Kyung Lee, Hiun Suk Chae, Hae Kyung Lee, Helicobacter Study Group
Ann Clin Microbiol 2018 September, 21(3): 58-63. Published on 20 September 2018.
Background: Helicobacter pylori infection in children causes gastrointestinal symptoms and iron deficiency anemia. This study aimed to investigate trends in H. pylori stool antigen (HpSA) positivity in children and the relationship between HpSA test results and anemia.
Methods: We analyzed the results of 2,762 HpSA tests and the correlation of hemoglobin and ferritin with HpSA in patients aged 0-18 years from 2008 to 2014 at a tertiary care center. Additionally, we prospectively evaluated HpSA test results and correlation with hemoglobin in 352 specimens obtained from five centers.
Results: From 2008-2014, the mean positive rate of the HpSA test was 5.8%, with a high of 9.1% in 2012 and a low of 2.3% in 2013. The positive rate correlated with age: 2.9% in 0-6-year-olds, 5.8% in 7-12-year-olds, and 10.6% in 13-18-year-olds (P＜0.0001). There was no difference in HpSA positivity in patients with (7.0%) and without (5.7%) anemia. Ferritin was significantly lower in patients with positive HpSA results than in those with negative results (P=0.0001). In a multicenter study, the positive rate of HpSA was 16.8%.
Conclusion: The rate of HpSA positivity was 5.8% in pediatric patients at a single center from 2008-2014, and this rate increased with age. Helicobacter pylori infection may be associated with iron deficiency, as ferritin level was significantly lower in HpSA-positive patients than HpSA-negative patients.
[in Korean]
Hee Sue Park, Bo Ra Son, Min Suk Song, Kyeong Seob Shin
Ann Clin Microbiol 2018 September, 21(3): 64-67. Published on 20 September 2018.
We describe a cutaneous abscess caused by Nocardia abscessus in a previously healthy woman. A 74- year-old woman presented with recurrent bullae on her left forearm that developed 1 week prior and was initially suspected to be a cutaneous infection with Mycobacteria or Tinea corporis. Histopathologically, the skin lesion formed an abscess. A smear revealed a few branched Gram-positive filamentous microorganisms that formed a creamy white colony on a blood agar plate after incubation for 3 days. The colony tested negative on acid-fast bacilli (AFB) staining, but was positive on modified AFB staining. The isolate was confirmed to be N. abscessus by 16S rRNA sequencing analysis. The isolate was susceptible to trimethoprim-sulfamethoxazole, amikacin, cefotaxime and erythromycin but resistant to penicillin. The patient was treated with clarithromycin but subsequently lost to follow-up. To the best of our knowledge, this is the first report of a human cutaneous infection with N. abscessus in Korea.
For Authors
Publisher
Sponsors
