Molecular and epidemiological characterization of HIV-1 infection networks involving transmitted drug resistance mutations in Northern Greece.

OBJECTIVES: To determine the contribution of transmission clusters to transmitted drug resistance (TDR) in newly diagnosed antiretroviral-naive HIV-1-infected patients in Northern Greece during 2000-07. METHODS: The prevalence of TDR was estimated in 369 individuals who were diagnosed with HIV-1 infection in the period 2000-07 at the National AIDS Reference Laboratory of Northern Greece. Phylogenetic analysis was performed using a maximum likelihood method on partial pol sequences. TDR was defined in accordance with the surveillance drug resistance mutation list (2009 update). RESULTS: The overall prevalence of TDR in our population was 12.5% [46/369, 95% confidence interval (CI) 9.1%-15.8%], comprising 7.6% (28/369) resistant to nucleoside reverse transcriptase inhibitors, 5.4% (20/369) resistant to non-nucleoside reverse transcriptase inhibitors and 3.3% (12/369) resistant to protease inhibitors. Dual class resistance was identified in 3.8% (14/369). Infection with subtype A was the sole predictor associated with TDR in multivariate analysis (odds ratio 2.15, 95% CI 1.10-4.19, P = 0.025). Phylogenetic analyses revealed three statistically robust transmission clusters involving drug-resistant strains, including one cluster of 12 patients, 10 of whom were infected with a strain carrying both T215 revertants and Y181C mutations. CONCLUSIONS: Our findings underline the substantial impact of transmission networks on TDR in our population.

HIV-1 subtypes and circulating recombinant forms (CRFs) in Northern Greece.

In order to understand the genetic diversity of virus isolates associated with the human immunodeficiency virus type one (HIV-1) epidemic in Northern Greece, 51 specimens from HIV-1 infected individuals were classified into subtypes by sequence-based phylogenetic analysis of the polymerase (pol) region of the viral genome. Forty two (82.3%) specimens were identified as pol subtype B, three (5.9%) as A, and one (2%) as CRF01_AE, while the remaining five (9.8%) specimens appeared to be complex recombinants, belonging to the Cypriot/Greek form CRF04_cpx. The proportion of CRF04_cpx strains is larger than previously reported, suggesting that the CRF04_cpx is significantly contributing to the Greek HIV-1 epidemic.

Genetic variation of the protease and reverse transcriptase genes in HIV-1 CRF04_cpx strains.

To gain information about the genetic variation of the protease and reverse transcriptase gene-coding regions in HIV-1 strains belonging to CRF04_cpx, genotyping and drug susceptibility testing were performed on serum samples derived from seven patients carrying sequences belonging to this circulating recombinant form. Substitutions classically associated with resistance to antiretroviral drugs were observed in six of seven samples, including G48V, V82A, L90M, M46I in the protease protein, and K70R, D69D/N, M184V, T215F, K103N in the reverse transcriptase protein. Genotypic resistance patterns of CRF04_cpx samples were found to be similar to those identified in subtype B viruses, suggesting that the drug-selective pressure has similar effects on both subtype B and CRF04_cpx.

Is Post-ERCP Pancreatitis a Genetically Predisposed Complication?

Background/Objectives. Pancreatitis remains the most common complication of ERCP. History of post-ERCP pancreatitis is an independent risk factor for a new episode, suggesting a genetic background. The N34S mutation in serine protease inhibitor Kazal type 1 (SPINK 1) gene may downregulate the threshold for the development of pancreatitis. The aim of the present study is to evaluate the presence of this mutation among patients with post-ERCP pancreatitis. Methods. During a period of four years, thirty patients with post-ERCP pancreatitis entered the study. Patients and procedural data were collected, focusing on risk factors for pancreatitis. Blood samples were taken for genetic testing for the presence of N34S mutation in SPINK 1 gene. After DNA extraction, we used an allele-specific polymerase chain reaction as an initial screening method for the N34S mutation, and in order to confirm the results and to determine the hetero- and homozygosity genotype status, we used a restriction fragment length polymorphism (RFLP) method. Results. None of the thirty patients was found to carry the N34S mutation, with both of the applied methods. Patients had an average of two of the known risk factors. Conclusion. SPINK1 N34S mutation does not seem to play a role in post-ERCP pancreatitis, but larger studies needed to confirm our results.