Patterns of drug resistance among newly diagnosed HIV-1 infected patients in Greece during the last decade: the crucial role of transmission networks.

INTRODUCTION: The prevalence of drug resistance is approximately 10% in Europe and North America among newly infected patients. We aim to investigate the temporal patterns of resistance among drug naive HIV-infected individuals in Greece and also to determine transmission networking among those with resistant strains. MATERIALS AND METHODS: Protease (PR) and partial reverse transcriptase (RT) sequences were determined from 2499 newly diagnosed HIV-1 patients, in Greece, during 2003-2013. Genotypic drug resistance was estimated using the HIVdb: Genotypic Resistance Interpretation Algorithm. We identified transmission clusters of resistant strains on the basis of a large collection of HIV-1 sequences from 4024 seropositives in Greece. Phylodynamic analysis was performed using a Bayesian method. RESULTS: We estimated drug resistance levels among naïve patients on the basis of all resistance mutations in PR and partial RT. The overall prevalence of resistance was 19.6% (490/2499). Resistance to NNRTIs was the most common (397/2499, 15.9%) followed by PIs (116/2499, 4.6%) and NRTIs (79/2499, 3.2%). We found a significant trend for decreasing resistance to NRTIs over time (6.7%-1.6%). There was no time trend for the overall PI and NNRTI resistance. The most frequently observed major resistant sites in PR were V82 (2.0%) and L90 (1.8%). In RT, we found E138 (58.6%), K103 (13.1%), V179 (8.4%) and T215 (7.1%), M41 (4.7%) associated with resistance to NNRTIs and NRTIs, respectively. The prevalence of K103N and E138Q were significantly increased during 2003-2013. Crucially, we found that both K103N, E138Q are associated with transmission networking within men having sex with men (MSM) and intravenous drug user (IDU) local networks. The K103N network included seropositives across Greece, while the latter only from the recent IDU outbreak in Athens metropolitan area (1). Phylodynamic analyses revealed that the exponential growth for K103N network started in 2009 (Figure 1) and for the E138Q in 2010. CONCLUSIONS: The overall resistance has been stable in Greece over time; however, specific NNRTI resistance patterns are increasing. Notably, they are associated with local transmission networking, thus suggesting that this is the cause for the increased patterns of NNRTI resistance and not multiple transmissions of resistant strains from different sources among treated individuals. Our study highlights the advance of molecular epidemiology for understanding the dynamics of resistance.

Effect of clarithromycin in patients with suspected Gram-negative sepsis: results of a randomized controlled trial.

BACKGROUND: A previous randomized study showed that clarithromycin decreases the risk of death due to ventilator-associated pneumonia and shortens the time until infection resolution. The efficacy of clarithromycin was tested in a larger population with sepsis. METHODS: Six hundred patients with systemic inflammatory response syndrome due to acute pyelonephritis, acute intra-abdominal infections or primary Gram-negative bacteraemia were enrolled in a double-blind, randomized, multicentre trial. Clarithromycin (1 g) was administered intravenously once daily for 4 days consecutively in 302 patients; another 298 patients were treated with placebo. Mortality was the primary outcome; resolution of infection and hospitalization costs were the secondary outcomes. RESULTS: The groups were well matched for demographics, disease severity, microbiology and appropriateness of the administered antimicrobials. Overall 28 day mortality was 17.1% (51 deaths) in the placebo arm and 18.5% (56 deaths) in the clarithromycin arm (P = 0.671). Nineteen out of 26 placebo-treated patients with septic shock and multiple organ dysfunctions died (73.1%) compared with 15 out of 28 clarithromycin-treated patients (53.6%, P = 0.020). The median time until resolution of infection was 5 days in both arms. In the subgroup with severe sepsis/shock, this was 10 days in the placebo arm and 6 days in the clarithromycin arm (P = 0.037). The cost of hospitalization was lower after treatment with clarithromycin (P = 0.044). Serious adverse events were observed in 1.3% and 0.7% of placebo- and clarithromycin-treated patients, respectively (P = 0.502). CONCLUSIONS: Intravenous clarithromycin did not affect overall mortality; however, administration shortened the time to resolution of infection and decreased the hospitalization costs.

Seroepidemiological study of pandemic influenza H1N1 following the 2009-2010 wave in Greece.

Knowledge of seroprevalence rates against 2009 pandemic H1N1 virus will assist vaccination recommendations and the preparation of the health-care system during subsequent years. This study was conducted in Greece during June-August 2010 to estimate the seroprevalence rate against pandemic H1N1 virus. Persons presenting in 29 health-care facilities across the country were studied. Seroprevalence was estimated employing a virus-free ELISA that specifically recognizes 2009 H1N1 virus antibodies in human sera. Sera collected from 2005 to April 2009 were also used to estimate pre-pandemic seroprevalence rates. A total of 954 persons were studied. The overall seroprevalence rate was 28.5% (95% confidence interval=25.6-31.3%). Age-specific rates were 34.2% in persons 0-4 years, 36.3% in persons 5-19 years, 25.0% in persons 20-39 years, 23.4% in persons 40-59 years, and 31.8% in persons ≥ 60 years. The highest rates were recorded in the Regions of Ionian Islands (67%) and Epirus (42.9%), while the lowest (8.4%) in the Region of Thessaly. Age-specific attack rates of infection during 2009-2010 were 28.8% in persons 0-4 years, 32.5% in persons 5-19 years, 14.3% in persons 20-39 years, 19.1% in persons 40-59 years, and 14.4% in persons ≥ 60 years. Multivariate analysis revealed that Region of residence and caring for children <5 years were associated with increased risk for seropositivity. Urbanity, personal and family characteristics, working in a health-care facility or in a school, history of pandemic H1N1 vaccination or history of influenza-like illness during 2009-2010 were not associated with increased risk for seropositivity.

Acute uncomplicated cystitis: from surveillance data to a rationale for empirical treatment.

The objectives of this study were to explore the epidemiological features and resistance rates in uropathogens isolated from cases of acute uncomplicated cystitis (AUC) in Greece, and subsequently to guide empirical treatment. Urine samples from outpatients aged >16 years were cultured and for each uropathogen isolated non-susceptibility to orally administered antimicrobial agents was defined. Demographic and clinical data were provided in questionnaire form. From January 2005 to March 2006 a total of 1936 non-duplicate positive urinary cultures were collected and 889 AUC cases were evaluated. Escherichia coli was the main aetiological agent (83%). In the AUC group, non-susceptibility rates for E. coli isolates were as follows: amoxicillin 25.8%; co-trimoxazole 19.2%; cefalothin 14.9%; nitrofurantoin 10.7%; amoxicillin/clavulanic acid 5.2%; nalidixic acid 6%; mecillinam 3.4%; ciprofloxacin 2.2%; cefuroxime 1.7%, and fosfomycin 1.6%. Amoxicillin and/or co-trimoxazole use in the previous 3 months was significantly associated with isolation of a co-trimoxazole-resistant E. coli isolate. The same applied for previous use of a fluoroquinolone agent and isolation of a ciprofloxacin-resistant E. coli isolate. In conclusion, increased co-trimoxazole non-susceptibility rates undermine its use as a first-line agent in empirical treatment, especially in cases of recent use of co-trimoxazole and/or amoxicillin. Fluoroquinolones display potent in vitro activity against community uropathogens, but prudent use is warranted for uncomplicated infections. Mecillinam and nitrofurantoin could serve as effective front-line agents in an effort to design fluoroquinolones-sparing regimens.

Increasing prevalence of HIV-1 subtype A in Greece: estimating epidemic history and origin.

BACKGROUND: In North America and Europe, human immunodeficiency virus (HIV)-1 infection has typically been dominated by subtype B transmission. More recently, however, non-B subtypes have been increasingly reported in Europe. METHODS: We analyzed 1158 HIV-1-infected individuals in Greece by DNA sequencing and phylogenetic analyses of protease and partial reverse-transcriptase regions. RESULTS: We found that the prevalence of non-B subtypes has increased over time and that this significant trend can be mainly attributed to subtype A, which eventually surpassed subtype B in prevalence in 2004 (42% and 33%, respectively). Multivariate analysis revealed that the year of HIV diagnosis was independently associated with subtype A infection (odds ratio for being infected with subtype A for a 10-year increase in the time period of diagnosis, 2.09 [95% confidence interval, 1.36-3.24]; P<.001). Phylogenetic analysis revealed that the subtype A epidemic in Greece is the result of a single founder event. The date of the most recent common ancestor of the subtype A in Greece was estimated to be 1977.9 (95% highest posterior density interval, 1973.7-1981.9). CONCLUSIONS: Subtype A circulates among the long-term residents of Greece. This is in contrast to the situation in most European countries, in which infection with non-B genetic forms is associated either with being an immigrant or heterosexual or with intravenous drug use.