Interference of confounding factors on the use of (1,3)-beta-D-glucan in the diagnosis of invasive candidiasis in the intensive care unit.

Invasive fungal infections (IFIs) are an increasing problem in intensive care units (ICUs), and conventional diagnostic methods are not always reliable or timely enough to deliver appropriate antimicrobial therapy. The dosage of fungal antigens in serum is a promising diagnostic technique, but several confounding factors, such as treatment with immunoglobulins (Ig), albumin, or antifungals, could interfere with the correct interpretation of the (1,3)-beta-D-glucan (BG) assay. This study assessed the reliability of the BG assay and the influence of timing and dosage of major confounding factors on circulating levels of IFI biomarkers. 267 ICU patients who underwent a BG assay were retrospectively studied. The timing and dosage of albumin, use of azole treatment, and infusions of intravenous IgG, red blood cells, concentrated platelets, and frozen plasma were analyzed to find possible correlations with the BG results. The sensitivity and specificity of the BG assay were calculated. The BG test in serum showed high sensitivity (82.9 %) but low specificity (56.7 %). The optimal cut-off for the test was 95.9 pg/mL. The mean BG level in proven invasive candidiasis was around 400 pg/mL. The only factor that was found to significantly confound (p < 0.05) the diagnostic performance of the BG assay was the administration of more than 30 g of albumin within 2 days prior to BG testing. The BG assay remains a useful diagnostic test in ICU patients and the levels of BG are useful in evaluating the positive predictive value of this biomarker. The only confounding factor in our study was the use of albumin.

A rare association of emphysematous pyelonephritis with unrecognized diabetes and polycystic kidney.

Emphysematous pyelonephritis (EPN) is a rare, severe, gas-forming infection for which the treatment of choice is often an immediate nephrectomy, although many reports exist of conservative treatment of cases with antibiotic therapy and percutaneous drainage of abscesses. It usually occurs in diabetic patients and less frequently in subjects with an obstruction of the corresponding renoureteral unit; other predisposing factors are not common. We report here the case of a 51 year-old woman with a rare association of unrecognized diabetes and bilateral polycystic kidney disease who developed monolateral EPN. She had an emergency right nephrectomy and was admitted to Intensive Care Unit (ICU) for septic shock after surgery, requiring intensive resuscitation. The patient was managed with Coupled Plasma Filtration Adsorption (CPFA). Her clinical conditions rapidly improved and the hemofiltration was soon suspended. Urine and blood cultures were positive for the same Escherichia coli, which was susceptible to all tested antibiotics. The patient was transferred to the Nephrology Division and was discharged from the hospital without further dialysis after 34 days. This case report is somewhat unique because of the unusual association between undetected diabetes and polycystic kidney as predisposing factors of a severe infection of the urinary tract.

Hyperacute unilateral gonococcal endophthalmitis in an HIV-infected man without genital infection.

PURPOSE: To demonstrate the necessity of obtaining an accurate history from patients presenting abnormal evolution of ophthalmologic diseases. METHODS: A 42-year-old patient, denying any previous ocular or systemic morbidity, presented with an unusual severe and hyperacute gonococcal endophthalmitis with corneal abscess but no concurrent genitourinary infection. Only after a further interview did the patient reveal his human immunodeficiency virus status and a previous diagnosis of acquired immunodeficiency syndrome. RESULTS: Adequate topical and intravenous antibiotic treatment and surgery led to salvage of the eye. CONCLUSIONS: An accurate history should be obtained by patients with an abnormal course of an ophthalmologic disease, focusing on immunologic deficiencies that can cause extremely serious ophthalmologic complications with ensuing risk of visual impairment or ocular loss (bulbar enucleation).

Secular trends in nosocomial candidaemia in non-neutropenic patients in an Italian tertiary hospital.

A retrospective study was performed in an Italian tertiary hospital to evaluate trends in candidaemia between 1992 and 2001, and to compare the characteristics of episodes of fungaemia between 1992--1997 and 1998--2001. In total, 370 episodes of candidaemia were identified, with an average incidence of 0.99 episodes/10 000 patient-days/year (range 0.49--1.29 episodes). On an annual trend basis, the overall incidence was essentially stable in surgical and medical wards, but decreased in intensive care units (ICUs) (p 0.0065). The average use of fluconazole was 37.9 g/10 000 patient-days/year (range 21.4--56.1 g), and did not change significantly during the 10-year period. Nearly two-thirds of patients were in ICUs at the onset of candidaemia, but none was neutropenic in either study period. Candida albicans remained the predominant species isolated (53.8% vs. 48.1%), followed by Candida parapsilosis, Candida glabrata and Candida tropicalis, the distribution of which did not change significantly. The 30-day crude mortality rate was essentially similar (44% vs. 35%) in both study periods. Thus the incidence of nosocomial candidaemia, although high in this institution, decreased among critically-ill patients during the 10-year period. This finding seemed to be related to an improvement in infection control practices, particularly regarding the prevention of intravascular catheter-related infections in ICUs. Although the overall use of fluconazole was considerable, no increase in azole-resistant non-albicans Candida spp. was detected.

Directed evolution to increase camptothecin sensitivity of human DNA topoisomerase I.

BACKGROUND: Human DNA topoisomerase I (top1) relaxes DNA supercoiling during basic nuclear processes. The enzyme is the main target of antitumor agents, such as camptothecins (CPT), that transform top1 into a DNA-damaging agent. RESULTS: By directed evolution of a C-terminal portion, we selected human top1 mutants that were 22-28-fold more CPT-sensitive than wild-type top1 in Saccharomyces cerevisiae cells. The evolved enzymes showed unique mutation patterns and were more processive in plasmid relaxation assays. A top1 mutant had only two amino acid changes in the linker domain, one of which may change a linker/core domain contact surface. The mutant stimulated DNA cleavage to higher levels than the wild-type enzyme and was more sensitive to CPT in a cleavage assay. Moreover, the mutant was more CPT-sensitive than wild-type top1 in a repair-deficient yeast strain. CONCLUSIONS: Mutations in the linker domain can affect DNA binding and CPT sensitivity of human top1. Such drug-hypersensitive topoisomerases may be useful in developing DNA cutters with high cell lethality and in new drug discovery programs.

Saccharification of bamboo carbohydrates for the production of ethanol.

Bamboo carbohydrates were hydrolyzed with commercial amylases and a mixture of fungal culture broths containing cellulolytic and hemicellulolytic enzymes. The effects of cooking temperature and the size of fiber particles were also investigated. It was found that the higher the cooking temperature, the higher the rate of sugar formation and the lower the viscosity of the slurry. Additions of cellulose and hemicellulose digesting enzymes increased the sugar yield and decreased the viscosity of both the cooked and noncooked slurries. A smaller size of particle appeared to favor the average saccharification rate. Although glucose, xylose, and cellobiose were present in the hydrolysates, only 50% of the total carbohydrate was digested, and 78.9% of this was converted to reducing sugars. The alcohol efficiency for the fermentation of cooked and noncooked mashes by Saccharomyces was about 85%.