Ceftazidime/avibactam in the era of carbapenemase-producing Klebsiella pneumoniae: experience from a national registry study.

BACKGROUND: Infections caused by KPC-producing Klebsiella pneumoniae (Kp) are associated with high mortality. Therefore, new treatment options are urgently required. OBJECTIVES: To assess the outcomes and predictors of mortality in patients with KPC- or OXA-48-Kp infections treated with ceftazidime/avibactam with an emphasis on KPC-Kp bloodstream infections (BSIs). METHODS: A multicentre prospective observational study was conducted between January 2018 and March 2019. Patients with KPC- or OXA-48-Kp infections treated with ceftazidime/avibactam were included in the analysis. The subgroup of patients with KPC-Kp BSIs treated with ceftazidime/avibactam was matched by propensity score with a cohort of patients whose KPC-Kp BSIs had been treated with agents other than ceftazidime/avibactam with in vitro activity. RESULTS: One hundred and forty-seven patients were identified; 140 were infected with KPC producers and 7 with OXA-48 producers. For targeted therapy, 68 (46.3%) patients received monotherapy with ceftazidime/avibactam and 79 (53.7%) patients received ceftazidime/avibactam in combination with at least another active agent. The 14 and 28 day mortality rates were 9% and 20%, respectively. The 28 day mortality among the 71 patients with KPC-Kp BSIs treated with ceftazidime/avibactam was significantly lower than that observed in the 71 matched patients, whose KPC-Kp BSIs had been treated with agents other than ceftazidime/avibactam (18.3% versus 40.8%; P = 0.005). In the Cox proportional hazards model, ultimately fatal disease, rapidly fatal disease and Charlson comorbidity index ≥2 were independent predictors of death, whereas treatment with ceftazidime/avibactam-containing regimens was the only independent predictor of survival. CONCLUSIONS: Ceftazidime/avibactam appears to be an effective treatment against serious infections caused by KPC-Kp.

First-year results of an antibiotic stewardship program in a Greek tertiary care hospital.

The aim of this study was to investigate the effect of the implementation of an antibiotic stewardship program (ASP) on antibiotic consumption in our 428-bed hospital. The Infection Control Committee implemented an ASP beginning in January 2016, aiming to reduce inappropriate antibiotic use through improved prescribing practices. The ASP included both pre-authorization and prospective audit and feedback strategies. We collected pharmacy and hospital data for the years 2015 (pre-intervention) and 2016 (post-intervention). Consumption data were expressed as daily defined doses (DDDs) per 100 patient-days (PD) and the significance of the differences between 2015 and 2016 was assessed by paired t-test. Antibiotic resistance rates for the most important hospital pathogens were monitored for 2015-2016. The ASP effectively reduced consumption of most antimicrobials; total antibiotic use decreased by 16.7% (from 104.3 in 2015 to 86.9 DDDs/100 patient-days in 2016, p < 0.001) owing to reduction of 19.1% for non-restricted and 13.8% for restricted antibiotics. Important restricted antimicrobials, such as colistin, carbapenems, quinolones and tigecycline showed significantly decreased usage post-intervention. Significant changes in the resistance rates were not observed, except a decreasing trend for colistin and tigecycline (Acinetobacter baumannii and Klebsiella pneumoniae) and also vancomycin (enterococci). The ASP was successful in terms of reducing the antibiotic consumption for the first year of its implementation. Interestingly, antimicrobials requiring pre-authorization exhibited a lower reduction than other antibiotics. Potential effects of the ASP in reducing resistance rates remain to be shown.

Prevalence of drug resistance among HIV-1 treatment-naive patients in Greece during 2003-2015: Transmitted drug resistance is due to onward transmissions.

BACKGROUND: The prevalence of HIV-1 drug resistance among treatment-naïve patients ranges between 8.3% and 15% in Europe and North America. Previous studies showed that subtypes A and B were the most prevalent in the Greek HIV-1 epidemic. Our aim was to estimate the prevalence of resistance among drug naïve patients in Greece and to investigate the levels of transmission networking among those carrying resistant strains. METHODS: HIV-1 sequences were determined from 3428 drug naïve HIV-1 patients, in Greece sampled during 01/01/2003-30/6/2015. Transmission clusters were estimated by means of phylogenetic analysis including as references sequences from patients failing antiretroviral treatment in Greece and sequences sampled globally. RESULTS: The proportion of sequences with SDRMs was 5.98% (n=205). The most prevalent SDRMs were found for NNRTIs (3.76%), followed by N(t)RTIs (2.28%) and PIs (1.02%). The resistance prevalence was 22.2% based on all mutations associated with resistance estimated using the HIVdb resistance interpretation algorithm. Resistance to NNRTIs was the most common (16.9%) followed by PIs (4.9%) and N(t)RTIs (2.8%). The most frequently observed NNRTI resistant mutations were E138A (7.7%), E138Q (4.0%), K103N (2.3%) and V179D (1.3%). The majority of subtype A sequences (89.7%; 245 out of 273) with the dominant NNRTI resistance mutations (E138A, K103N, E138Q, V179D) were found to belong to monophyletic clusters suggesting regional dispersal. For subtype B, 68.1% (139 out of 204) of resistant strains (E138A, K103N, E138Q V179D) belonged to clusters. For N(t)RTI-resistance, evidence for regional dispersal was found for 27.3% and 21.6% of subtype A and B sequences, respectively. CONCLUSIONS: The TDR rate based on the prevalence of SDRM is lower than the average rate in Europe. However, the prevalence of NNRTI resistance estimated using the HIVdb approach, is high in Greece and it is mostly due to onward transmissions among drug-naïve patients.

Intracranial haemorrhage possibly related to Tipranavir in an HIV-1 patient with cryptococcal meningitis.

A 55-year-old HIV-infected patient on antiretroviral treatment with Ritonavir-boosted Tipranavir as part of HAART developed intracranial haemorrhage during the acute phase of cryptococcal meningitis. CT scan and MRI confirmed the intracranial haemorrhage. Positive cryptococcal antigen and cultures of both blood and CSF confirmed the diagnosis of meningitis caused by Cryptococcus neoformans. There was no evidence of any bleeding disorder, use of aspirin or antiplatelet agents. The patient was treated with Liposomal Amphotericin B for cryptococcal meningitis. No special treatment was needed for the intracranial haemorrhage, but Tipranavir was discontinued and replaced by Kaletra and Saquinavir. Intracranial haemorrhage could be related to Tipranavir and cryptococcal meningitis was a predisposing factor. Headache stopped 3 days after starting antifungal treatment. To the best of our knowledge, this is the first reported case of intracranial haemorrhage related to Tipranavir treatment after the end of the "RESIST" studies and the only one related to meningitis.

Body composition changes in protease inhibitor-naive HIV-infected patients treated with two nucleoside reverse transcriptase inhibitors.

OBJECTIVES: In the era of highly active antiretroviral treatment (HAART), there are insufficient data regarding lipodystrophy syndromes in HIV-1-infected patients treated with regimens that do not include protease inhibitors (PIs). We studied changes in body composition in HIV-1-infected patients before and 2 years after starting a non-PI-containing antiretroviral treatment regimen. METHODS: We studied retrospectively the whole body dual energy X-ray absorptiometry (DEXA) scans of 23 PI-naive HIV-1-infected patients (17 males, six females), aged 37.4 +/- 9.3 years with mean CD4 count 401 +/- 130 cells/microL. Thirteen patients were on zidovudine (ZDV) + lamivudine (3TC) and 10 on ZDV + didanosine (ddI). Subjects were evaluated before the beginning of antiretroviral treatment and approximately 24 months later. For each patient body weight, CD4 T-cell counts, bone mineral content (BMC), bone mineral density (BMD) and whole body as well as regional fat and lean body mass were evaluated. RESULTS: A significant decrease in BMC was observed, although the T scores remained within the normal limits. Our patients also exhibited a significant decrease in body weight due almost exclusively to fat loss, while lean mass was minimally affected. Fat loss was statistically significant in the arms and legs, but not in the trunk. The above changes were most prominent in the ZDV + 3TC treatment group; in this group of patients, fat loss was also evident in the trunk. Patients on ZDV + ddI, on the other hand, only showed a significant increase in their legs' lean mass; they preserved their total fat mass and exhibited no other significant changes between the two assessments. CONCLUSIONS: Dual NRTI therapy contributes to fat loss and reduction of bone mineral content in otherwise healthy, clinically stable, PI-naive HIV-infected adults. Compared with patients on ZDV + ddI, patients on ZDV + 3TC had a more prominent fat loss in all body regions.

Virological and immunological response to HAART therapy in a community-based cohort of HIV-1-positive individuals.

PURPOSE: To determine virological and immunological response to highly active antiretroviral therapy (HAART) and to investigate factors influencing response in a community-based setting. METHOD: Plasma HIV RNA levels and CD4 cell counts were studied in 168 unselected individuals starting HAART including indinavir or ritonavir or hard-gel saquinavir-containing regimens. RESULTS: Overall, 60% of the patients reduced their HIV RNA to below 500 Eq/mL, but half of them experienced a subsequent virologic rebound. Patients with higher baseline HIV RNA, higher baseline CD4 cell count, and simultaneous initiation of combination therapy and patients on indinavir or ritonavir regimen were more likely to have virologic response within 6 months since HAART initiation. Patients with lower baseline CD4 cell count and with lower rates of viral clearance had a higher probability of a subsequent virologic rebound. Forty percent of the patients had increased their CD4 cell counts by more than 100 cells/microL (immunologic response). The probability of immunologic response was independent of baseline HIV RNA levels and CD4 cell count; however, the more complete the virologic suppression, the higher the probability of immunologic response. Thirty percent of the patients had discordance between virologic and immunologic responses. CONCLUSION: The rate of virologic failure in this unselected group of patients was higher than that observed in randomized clinical trials, but only a minority (11%) of the patients were treatment naïve. Starting combination therapy simultaneously and initiating antiretroviral therapy before advanced HIV disease has developed predict virologic response, whereas the magnitude of viral suppression predicts mid to long immunological response.

Molecular characterization of a complex, recombinant human immunodeficiency virus type 1 (HIV-1) isolate (A/G/J/K/?): evidence to support the existence of a novel HIV-1 subtype.

Recombination is one of several factors that contribute to the great genetic diversity of human immunodeficiency virus type 1 (HIV-1). In the current study, analysis of the full-length genome of a novel complex mosaic HIV-1 isolate (99GR303) from a Greek sailor who was possibly infected in Sierra Leone, Africa is presented. The 99GR303 isolate was found to comprise genomic regions belonging to subtypes A, G, J and K as well as of regions of a subtype that remains unclassified. For a partial region of env as well as vpr, no apparent similarity to the known HIV-1 subtypes or to any of the circulating recombinant forms was found. In fact, in the partial env gene, including the C2-V3 region, the 99GR303 isolate formed a new clade, suggesting the existence of an additional HIV-1 subtype. Thus, novel recombinants embody partial genomic regions which may have originated either from subtypes that existed in the past and became extinct or from contemporary subtypes that are extremely rare.

Comparative in-vitro activity of azithromycin, macrolides (erythromycin, clarithromycin and spiramycin) and streptogramin RP 59500 against oral organisms.

The in-vitro activities of azithromycin, clarithromycin, spiramycin and RP 59500 were compared with erythromycin against a wide range of oral organisms which have been implicated in oral infections and/or endocarditis (clindamycin was included for oral streptococci). All compounds tested showed good activity against many of these organisms, although some variation was observed with different species. Clarithromycin was the most active of the antibiotics tested against Gram-positive anaerobes, including Actinomyces spp., Propionibacterium spp., Lactobacillus spp. and Bifidobacterium dentium. Azithromycin was slightly less active than erythromycin against these species. In general, RP 59500 had higher MICs than the macrolides, other than spiramycin, against these organisms, but was superior in activity against Peptostreptococcus spp., inhibiting all isolates at 2 mg/L. Azithromycin was, in general, the most active antibiotic tested against the Gram-negative anaerobes: Fusobacterium spp., Bacteroides spp., Wolinella spp., Actinobacillus actinomycetemcomitans, Selenomonas spp. and Mitsuokella multiacida, including those isolates which were insusceptible to erythromycin. Clarithromycin showed similar activity to erythromycin against most Gram-negative species, but was superior against Capnocytophaga ochraceus and Eikenella corrodens. RP 59500 was less active than the macrolides against most Gram-negative anaerobes, but was superior to erythromycin and clarithromycin against Fusobacterium spp. and Leptotrichia buccalis, some strains of which were moderately resistant to erythromycin. The macrolides and clindamycin were about equally active against the oral streptococci, whereas RP 59500 showed lower inhibitory activity. The in-vitro results suggest that azithromycin and clarithromycin may be of value in the treatment of dental sepsis and the prophylaxis of endocarditis. RP 59500 showed useful activity against Gram-positive anaerobes and, because of its bactericidal activity against oral streptococci, may also prove to have a role in these areas.