Successful therapy of Candida pulcherrima fungemia in a premature newborn with liposomal amphotericin B and micafungin.

New Candida species may cause bloodstream infections challenging current therapeutic approaches because of unpredictable susceptibility and virulence. In the present report, we describe a fungemia case due to Candida pulcherrima in a premature neonate. After full in vitro diagnostic workup, the neonate was successfully treated with liposomal amphotericin B and micafungin achieving rapid fungal eradication from blood.

Susceptibility patterns to extended-spectrum cephalosporins among Enterobacteriaceae harbouring extended-spectrum ß-lactamases using the updated Clinical and Laboratory Standards Institute interpretive criteria.

We examined the effect of applying the updated 2010 Clinical and Laboratory Standards Institute (CLSI) susceptibility breakpoints for extended-spectrum cephalosporins (ESCs) to detect extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae. In total, 202 ESBL-producing, plasmidic AmpC- and carbapenemase-negative isolates derived from separate patients were collected from three Greek hospitals during 2007-2011, including 150 Escherichia coli, 43 Klebsiella pneumoniae and 9 Enterobacter cloacae clinical isolates. ESBLs were detected using the ESBL CLSI confirmatory test and PCR assays. Sequencing analysis showed that 91 (45.0%) of the ESBL-producers carried the bla(CTX-M-3) gene, 66 (32.7%) carried the bla(CTX-M-15) gene and the remaining 45 (22.3%) carried the bla(SHV-5) gene. Minimum inhibitory concentrations for cefotaxime, ceftazidime and cefepime were determined by the agar dilution method. Based on the new CLSI breakpoints, 13 (6.4%) of the ESBL-producers were susceptible to cefotaxime, 90 (44.6%) to ceftazidime and 112 (55.4%) to cefepime; as many as 145 (71.8%) were susceptible to at least one ESC. Among the 150 E. coli, 12 (8.0%), 87 (58.0%) and 79 (52.7%) were susceptible to cefotaxime, ceftazidime and cefepime, respectively, whilst among the 43 K. pneumoniae, 1 (2.3%), 3 (7.0%) and 25 (58.1%) were susceptible to the above ESCs, respectively. None of the nine E. cloacae were susceptible to cefotaxime and ceftazidime, but all except one were susceptible to cefepime. By implementation of the new 2010 CLSI breakpoints, a considerable proportion of ESBL-possessing Enterobacteriaceae would be reported as susceptible, mostly to ceftazidime and cefepime, leading to possible infection control and therapeutic implications.

Comparative evaluation of a prototype chromogenic medium (ChromID CARBA) for detecting carbapenemase-producing Enterobacteriaceae in surveillance rectal swabs.

Carbapenemase-producing Enterobacteriaceae (CPE) are an increasing problem worldwide, and rectal swab surveillance is recommended as a component of infection control programs. The performance of a prototype chromogenic medium (chromID CARBA) was evaluated and compared with media tested by four other screening methods: (i) overnight selective enrichment in 5 ml tryptic soy broth with a 10-µg ertapenem disk followed by plating onto MacConkey agar (CDC-TS), (ii) short selective enrichment in 9 ml brain heart infusion broth with a 10-µg ertapenem disk followed by plating onto chromID ESBL medium (ESBL-BH), (iii) direct plating onto chromID ESBL, and (iv) direct plating onto MacConkey agar supplemented with meropenem (1 µg/ml) (MCM). The screening methods were applied to detect CPE in 200 rectal swab specimens taken from different hospitalized patients. Identification and antimicrobial susceptibility were performed by the Vitek 2 system. Carbapenem MICs were checked by Etest. Carbapenemase production was confirmed using the modified Hodge test, combined-disk tests, and PCR assays. In total, 133 presumptive CPE strains were detected. Phenotypic and genotypic assays confirmed 92 strains to be CPE (56 KPC-positive Klebsiella pneumoniae, 29 VIM-positive K. pneumoniae, and 7 KPC-positive Enterobacter aerogenes strains) recovered from 73 patients, while the remaining 41 strains were confirmed to be CPE negative (19 ESBL producers and 22 nonfermenters). chromID CARBA, ESBL-BH, and chromID ESBL exhibited the highest sensitivity (92.4%), followed by CDC-TS and MCM (89.1%) (P = 0.631). The specificity was greater for chromID CARBA (96.9%) and ESBL-BH (93.2%) than for CDC-TS (86.4%), MCM (85.2%), and chromID ESBL (84.7%) (P = 0.014). In conclusion, chromID CARBA was found to be a rapid and accurate culture screening method for active CPE surveillance.

Two cases of severe sepsis caused by Bacillus pumilus in neonatal infants.

Bacillus pumilus is an environmental contaminant that has been rarely associated with clinical infections. Here, two cases of severe sepsis caused by B. pumilus are described in two full-term neonates; one in a female infant with no factors predisposing her to infection and the other in a male infant requiring mechanical ventilation and an intravenous catheter. In both cases, the micro-organism was recovered from repeated blood cultures and was identified using biochemical assays and 16S rRNA gene sequencing. Both infants were successfully treated with vancomycin. This report reveals the potential role of B. pumilus as a bloodstream pathogen during infancy.

In vivo acquisition of a plasmid-mediated bla(KPC-2) gene among clonal isolates of Serratia marcescens.

Three patients admitted to a Greek hospital were infected with Serratia marcescens isolates that exhibited reduced susceptibility to carbapenems and harbored Klebsiella pneumoniae carbapenemase (KPC) enzymes. In two of these cases, the patients were initially infected by carbapenem-susceptible S. marcescens isolates. Molecular typing and plasmid analysis suggested that all three patients had clonally indistinguishable isolates of S. marcescens that acquired a plasmid-mediated bla(KPC-2) gene during the hospitalization.

Polymorphisms of fractalkine receptor CX3CR1 gene in patients with symptomatic and asymptomatic carotid artery stenosis.

AIM: The chemokine fractalikine is expressed in vascular endothelium, exerting a pro-atherogenic effect. Two single-nucleotide polymorphisms of the CX3CR1 gene (T280M and V249I) affect frac-talkine receptor expression and function. We aimed to assess the prevalence of CX3CR1 polymor-phisms and the association with ischemic cerebrovascular attacks in a cohort of carotid atheromatous disease patients and age-matched controls. METHODS: Using PCR-RFLP, we analyzed allelotypes for T280M and V249I in 150 patients with and 151 controls without carotid atherosclerosis assessed using carotid duplex ultrasound; the subjects were patients admitted for any reason to a tertiary hospital. Genotype data were compared with modifiable risk factors for cerebrovascular disease and the reason for admission, using ischemic stroke as an endpoint. Stroke types associated with carotid atherosclerosis were analysed separately. RESULTS: The M280 allelic frequency was lower among carotid atherosclerosis patients than controls (0.15 versus 0.23, adjusted OR 0.47, 95% CI 0.30-0.74). Absence of M280 allele was an indepen-dent factor associated with carotid atherosclerosis (OR 3.70, 95% CI 1.92-7.14), stronger than hypertension, dyslipidemia, diabetes and cigarette smoking. The I249 allele was also under-repre-sented in carotid atherosclerosis; this was not statistically significant. T280M and V249I genotypes were not associated with admission due to ischemic stroke of the large vessel subtype (TOAST classi-fication, 73 episodes), whereas carotid atherosclerosis, previous ischemic event, age, hypertension, diabetes, hyperlipidemia and cigarette smoking were all independently associated. CONCLUSIONS: The M280 fractalkine receptor gene allele is associated with a lower risk of carotid ath-eromatous disease, independent from the modifiable cerebrovascular risk factors.

The effect of an exon 12 polymorphism of the human thromboxane synthase (CYP5A1) gene in stroke patients.

BACKGROUND: To examine the prevalence of an exon 12 polymorphism on the human Thromboxane synthase (CYP5A1) gene. MATERIAL/METHODS: Using sequence-specific PCR, we examined the allelic prevalence in 237 Greek patients with ischemic strokes and in 171 controls. In addition, we compared the CYP5A1 allelic prevalence in 71 patients with stroke recurrence despite Aspirin use, in comparison with patients who have not experienced recurrent stroke while taking Aspirin. RESULTS: The frequencies of the CYP5A1*9 mutant (substitution of guanine by adenine near the heme-binding catalytic domain) and of the wild-type allele were 0.197 and 0.803, respectively; they did not differ significantly between stroke patients and controls. The wild-type allele was more frequent in the Cretan population compared to continental Greece (OR 1.80, 95% CI 1.19-2.74). The wild-type allele was more frequent among hypertensive and less frequent among diabetic stroke sufferers, respectively. The CYP5A1*9 mutant was significantly more prevalent among stroke patients with history of previous cerebrovascular attacks (p<0.01); and among those who failed secondary Aspirin prophylaxis even after adjusting for the common risk factors for cardiovascular disease (OR 1.49, 95% CI 1.06-2.11). CONCLUSIONS: Allelic prevalence of the CYP5A1 exon 12 might differ between geographic areas within the same ethnic group, and is associated with particular characteristics of stroke patients. Allele mutations can abolish the enzymatic activity of thromboxane synthase, via impaired heme binding, associated with defective response to Aspirin used as secondary prevention, an effect independent from the conventional risk factors for cerebrovascular disease.