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Background: A persistent increase of tuberculosis cases has recently been noted in the Ukraine. The reported incidence of drug-resistant isolates of M. tuberculosis is growing steadily; however, data on the genetic variation of isolates of M. tuberculosis circulating in northern Ukraine and on the spectrum and frequency of occurrence of mutations determining resistance to the principal anti-tuberculosis drugs isoniazid and rifampicin have not yet been reported. Methods: Isolates of M. tuberculosis from 98 tuberculosis patients living in Kharkiv Oblast (Ukraine) were analyzed using VNTR- and RFLP-IS6110-typing methods. Mutations associated with resistance to rifampicin and isoniazid were detected by RFLP-PCR methods, and also confirmed by sequencing. Results: We identified 75 different genetic profiles. Thirty four (34%) isolates belonged to the Beijing genotype and 23 (23%) isolates belonged to the LAM family. A cluster of isolates belonging to the LAM family had significant genetic heterogeneity, indicating that this family had an ancient distribution and circulation in this geographical region. Moreover, we found a significant percentage of the isolates (36%) belonged to as yet unidentified families of M. tuberculosis or had individual non-clustering genotypes. Mutations conferring rifampicin and isoniazid resistance were detected in 49% and 54% isolates, respectively. Mutations in codon 531 of the rpoB gene and codon 315 of the katG gene were predominant among drug-resistant isolates. An association was found for belonging to the LAM strain family and having multiple drug resistance (R = 0.27, p = 0.0059) and also for the presence of a mutation in codon 531 of the rpoB gene and belonging to the Beijing strain family (R = 0.2, p = 0.04). Conclusions: Transmission of drug-resistant isolates seems to contribute to the spread of resistant TB in this oblast. The Beijing genotype and LAM genotype should be seen as a major cause of drug resistant TB in this region. [ABSTRACT FROM AUTHOR]

Background:The Chernobyl accident resulted in an unprecedented number of radiation-induced thyroid cancers in young individuals as detected by national and international screening programs. The vast majority of thyroid malignancies were papillary carcinomas that, despite being similar by histopathology, displayed large variability in clinical course. The correlations between ultrasound (US) and clinicopathological features in young patients with radiation-induced thyroid cancer, however, have not been well studied. Because of the importance of US for deciding which subjects should have fine-needle aspiration biopsy, we assessed the US features of papillary thyroid carcinoma in patients exposed to Chernobyl fallouts.Design:We performed a retrospective multivariate logistic regression analysis of US features, clinicopathological data, and the latency period between radiation exposure and the diagnosis of cancer in 94 patients who were 10.6–34.3 years old (16.5 ± 6.2, mean ± standard deviation) at the time of diagnosis and 0.1–18.0 years old (5.6 ± 4.2) at the time of the Chernobyl accident.Results:Nodules greater than 10 mm were associated with the higher frequency of irregular margins (p= 0.001), longer period of latency (p= 0.016), and bilateral lymph node involvement (p= 0.025). Irregular tumor margins correlated with the shorter period of latency (p= 0.009) and unilateral nodal disease (p= 0.010). Hypoechoic nodules were observed more frequently in female patients (p= 0.012), in the absence of halo (p= 0.003) or calcifications (p= 0.005). Hypoechogenicity also correlated with the shorter latency (p= 0.015) and younger age of patients (p= 0.048).Conclusions:Irregular nodule margins, a usual sign of malignancy, are less useful in detecting thyroid cancers in radiation-exposed patients with tumors less than 10 mm. Thyroid cancers that are detected after longer latent periods display less of the US features characteristic of a malignant process, while benign US features are observed more frequently. Therefore, we recommend fine-needle aspiration biopsy to ensure early diagnosis of thyroid cancer for patients with a history of radiation exposure, even if their nodules are less than 10 mm. [ABSTRACT FROM AUTHOR]