Recent trends in clinically significant nontuberculous Mycobacteria isolates at a Korean general hospital.

Lung disease caused by nontuberculous mycobacteria (NTM) represents an increasing proportion of all mycobacterial diseases. We investigated recent occurrences of NTM and evaluated the clinical significance of NTM isolates from 752 respiratory specimens collected from patients at National Health Insurance Service Ilsan Hospital between January 2007 and May 2011. Specimens were incubated on solid and liquid media (BACTEC MGIT 960, BD, USA) for 6-8 weeks, and PCR and reverse blot hybridization were performed (REBA Myco-ID, Molecules & Diagnostics, Korea). Clinical features of the patients were reviewed through medical records. The most frequently isolated organism was Mycobacterium avium (46.7%), followed by M. intracellulare (14.8%), M. fortuitum (7.2%), and M. abscessus (6.6%). The most common mycobacteria among definitive cases of NTM lung disease were M. avium (42/351, 12.0%), M. intracellulare (19/111, 17.1%), M. abscessus (11/50, 22.0%), M. massiliense (4/13, 30.8%), and M. fortuitum (4/54, 7.4%). Clinically significant cases of NTM lung disease increased from 4 patients in 2007 to 32 in 2011. The mean patient age was 64 yr (range: 35-88 yr), and 58 (64%) patients were women. Patients suffered from cough, productive sputum, and hemoptysis. In summary, the most common mycobacteria causing NTM lung disease were M. avium and M. intracellulare; however, cases of M. massiliense and M. abscessus infection are on the rise in Korea.

Automated detection of malaria-associated pseudoeosinophilia and abnormal WBC scattergram by the Sysmex XE-2100 hematology analyzer: a clinical study with 1,801 patients and real-time quantitative PCR analysis in vivax malaria-endemic area.

Recently, the XE-2100 hematology analyzer was investigated in a rather small patient group; pseudoeosinophilia or abnormal white blood cell (WBC) scattergrams reported by this instrument were considered as significantly valuable diagnostic parameters in detecting vivax malaria. This study was conducted not only to assess the usefulness of pseudoeosinophilia or abnormal WBC scattergram in vivax malaria-endemic areas with large patient groups (N = 1,801) but also to investigate the correlation of parasitemia and platelet count with pseudoeosinophilia and abnormal WBC scattergrams. Of the 1,801 analyzed patients, 413 (22.9%) were found to have malaria by Wright-Giemsa stained blood smears. Overall, either pseudoeosinophilia or abnormal WBC scattergram was detected in 191 of 413 malaria patients and 4 of 1,388 patients without malaria (sensitivity = 46.2%, specificity = 99.7%). We suggest that clinical hematology laboratories using the XE-2100 analyzer should be aware of such specific parameters, even with the absence of a clinical request.

Oxidative status in iron-deficiency anemia.

Oxidative stress is an imbalance between free radicals and antioxidant molecules that can play an important role in the pathogenesis of iron-deficiency anemia (IDA). The aim of this study was to investigate oxidative status in patients with IDA and alteration of oxidative status after iron treatment. Thirty-three female patients with IDA and 25 healthy controls were included in this study. Oxidant and total antioxidant capacity were determined using free oxygen radicals test and free oxygen radicals defence (Form CR 3000, Callegari, Parma, Italy). Catalase activity was measured by spectrophotometer using a commercially available kit (Bioxytech Catalase-520, OxisResearch, Portland, OR). Oxidant activity in patients with IDA was significantly higher than controls (P<0.05), while total antioxidant and catalase activity were significantly lower (P<0.05). After treatment, oxidant, antioxidant, and catalase activity reached the levels of the control group, and no significant differences were observed among groups (P>0.05). In conclusion, our data indicate that blood reactive oxygen species was lower and total antioxidant and catalase activity were higher after rather than before treatment in patients with IDA. The results of our study support the higher oxidative stress hypothesis in IDA; however, due to the limited number of cases included, more studies may be required to confirm the results.

JAK2 V617F/C618R mutation in a patient with polycythemia vera: a case study and review of the literature.

The acquired Janus kinase 2 (JAK2) V617F mutation shows a high frequency in diverse BCR/ABL-negative chronic myeloproliferative disorders (CMPD), and it is typically associated with polycythemia vera (PV). The frequency of JAK2 V617F mutation is about 90% in patients with PV, 50-60% in patients with essential thrombocythemia (ET), primary myelofibrosis (PMF), and less in patients with other myeloid neoplasms, while extremely rare in lymphoid malignancies. About 20 kinds of novel mutations of JAK2 other than V617F have been reported recently in the literature. Among these mutations, only one case of JAK2 V617F/C618R has been reported in a 67-year-old patient with PV. Here, we report a rare case of JAK2 V617F/C618R in a 41-year-old Korean male patient with review of the relevant literature on JAK2 mutations other than V617F. Although the frequency of JAK2 mutations other than the V617F is very low, this study emphasizes the need for assiduous analysis of the JAK2 gene to characterize new mutations, to determine their frequency, and to improve understanding of the clinical phenotypes as well as prognostic and biologic features associated with these mutations.

A novel de novo mutation in the serine-threonine kinase STK11 gene in a Korean patient with Peutz-Jeghers syndrome.

BACKGROUND: Peutz-Jeghers syndrome (PJS) is an unusual autosomal dominant disorder characterized by mucocutaneous pigmentation and multiple gastrointestinal hamartomatous polyps. Patients with PJS are at an increased risk of developing multi-organ cancer, most frequently those involving the gastrointestinal tract. Germline mutation of the STK11 gene, which encodes a serine-threonine kinase, is responsible for PJS. METHODS: Using DNA samples obtained from the patient and his family members, we sequenced nine exons and flanking intron regions of the STK11 gene using polymerase chain reaction (PCR) and direct sequencing. RESULTS: Sequencing of the STK11 gene in the proband of the family revealed a novel 1-base pair deletion of guanine (G) in exon 6 (c.826delG; Gly276AlafsX11). This mutation resulted in a premature termination at codon 286, predicting a partial loss of the kinase domain and complete loss of the C-terminal domain. We did not observe this mutation in both parents of the PJS patient. Therefore, it is considered a novel de novo mutation. CONCLUSION: The results presented herein enlarge the spectrum of mutations of the STK11 gene by identifying a novel de novo mutation in a PJS patient and further support the hypothesis that STK11 mutations are disease-causing mutations for PJS with or without a positive family history.