Butyricimonas virosa bacteraemia and bowel disease: case report and review.

Only two cases of human infection with the anaerobic Gram-negative bacillus Butyricimonas virosa have been previously reported. We describe the case of a 69-year-old man with B. virosa and diverticulitis, further supporting an association of bacteraemia with this pathogen to bowel disease. We also summarize the characteristics of the previously described cases.

Diagnosis and inflammatory response of patients with candiduria.

Candiduria is common in hospitalised patients, but the clinical relevance is still unclear. This study was done to further our knowledge on detection of and host responses to candiduria. Urines and clinical data from 136 patients in whom presence of yeast was diagnosed by microscopic urinalysis were collected. Diagnosis by standard urine culture methods on blood and MacConkey agar as well as on fungal culture medium (Sabouraud dextrose agar) was compared. Inflammatory parameters (IL-6 and IL-17, Ig) were quantified in the urine and compared with levels in control patients without candiduria. Standard urine culture methods detected only 37% of Candida spp. in urine. Sensitivity was especially low (23%) for C. glabrata and was independent of fungal burden. Candida specific IgG but not IgA was significantly elevated when compared with control patients (P < 0.0001 and 0.07 respectively). In addition, urine levels of IL-6 and IL-17 were significantly higher in candiduric patients when compared with control patients (P < 0.001). Multivariate analysis documented an independent association between an increased IgG (odds ratio (OR) 136.0, 95% confidence interval (CI) 25.7-719.2; P < 0.0001), an increased IL-17 (OR 17.4, 95% CI 5.3-57.0; P < 0.0001) and an increased IL-6 level (OR 4.9, 95% CI 1.9-12.4; P = 0.001) and candiduria. In summary, our data indicate that clinical studies on candiduria should include fungal urine culture and that inflammatory parameters may be helpful to identify patients with clinically relevant candiduria.

Successful treatment of a left ventricular assist device infection with daptomycin non-susceptible methicillin-resistant Staphylococcus aureus: case report and review of the literature.

Recipients of left ventricular assist devices (LVADs) are highly susceptible to the development of infections with multidrug-resistant (MDR) organisms. We describe the case of a patient with an LVAD who developed a device-related, daptomycin non-susceptible, methicillin-resistant Staphylococcus aureus infection, highlighting this patient population as highly vulnerable to the development of such antimicrobial resistance. This report includes a thorough review of the literature on the mechanisms of development of daptomycin non-susceptibility and suggests ways to prevent its emergence. We also provide and underscore the appropriate guidelines to abide by when attempting to control infections with such resistant isolates. This case also demonstrates the importance of definitive treatment with LVAD removal and transplantation as a component of appropriate management of invasive LVAD infections. In addition, we suggest that even infections with MDR organisms may not adversely affect post-transplant outcomes.

Biofilm formation by and antifungal susceptibility of Candida isolates from urine.

Biofilm formation (BF) in the setting of candiduria has not been well studied. We determined BF and MIC to antifungals in Candida spp. isolates grown from urine samples of patients and performed a retrospective chart review to examine the correlation with risk factors. A total of 67 Candida spp. isolates were grown from urine samples from 55 patients. The species distribution was C. albicans (54%), C. glabrata (36%), and C. tropicalis (10%). BF varied greatly among individual Candida isolates but was stable in sequential isolates during chronic infection. BF also depended on the growth medium and especially in C. albicans was significantly enhanced in artificial urine (AU) compared to RPMI medium. In nine of the C. albicans strains BF was 4- to 10-fold higher in AU, whereas in three of the C. albicans strains and two of the C. glabrata strains higher BF was measured in RPMI medium than in AU. Determination of the MICs showed that planktonic cells of all strains were susceptible to amphotericin B (AMB) and caspofungin (CASPO) and that three of the C. glabrata strains and two of the C. albicans strains were resistant to fluconazole (FLU). In contrast, all biofilm-associated adherent cells were resistant to CASPO and FLU. The biofilms of 14 strains (28%) were sensitive to AMB (MIC(50) of <1 mug/ml). Correlation between degree of BF and MIC of AMB was not seen in RPMI grown biofilms but was present when grown in AU. A retrospective chart review demonstrated no correlation of known risk factors of candiduria with BF in AU or RPMI. We conclude that BF is a stable characteristic of Candida strains that varies greatly among clinical strains and is dependent on the growth medium. Resistance to AMB is associated with higher BF in AU, which may represent the more physiologic medium to test BF. Future studies should address whether in vitro BF can predict treatment failure in vivo.

Development of candidemia on caspofungin therapy: a case report.

Caspofungin, an echinocandin, is approved for use in invasive candidiasis. Few cases of break-through candidal infections during caspofungin therapy have been reported and none have involved Candida parapsilosis. Here, we report a patient who developed multiple post-operative complications after pancreaticoduodenectomy for a pancreatic mass, including fungemia due to C. parapsilosis, while on caspofungin for treatment of Candida glabrata peritonitis. The fungemia resolved after a central venous catheter was removed and therapy was switched from caspofungin to amphotericin B lipid complex. Studies of C. parapsilosis susceptibility and the pharmacodynamics and drug interactions of caspofungin that may contribute to breakthrough fungemia are discussed.

In vitro activities of ciprofloxacin and rifampin alone and in combination against growing and nongrowing strains of methicillin-susceptible and methicillin-resistant Staphylococcus aureus.

We characterized the effects of ciprofloxacin and rifampin alone and in combination on Staphylococcus aureus in vitro. The effects of drug combinations (e.g., indifferent, antagonistic, or additive interactions) on growth inhibition were compared by disk approximation studies and by determining the fractional inhibitory concentrations. Bactericidal effects in log-phase bacteria and in nongrowing isolates were characterized by time-kill methods. The effect of drug combinations was dependent upon whether or not cells were growing and whether killing or growth inhibition was the endpoint used to measure drug interaction. Despite bactericidal antagonism in time-kill experiments, our in vitro studies suggest several possible explanations for the observed benefits in patients treated with a combination of ciprofloxacin and rifampin for deep-seated staphylococcal infections. Notably, when growth inhibition rather than killing was used to characterize drug interaction, indifference rather than antagonism was observed. An additive bactericidal effect was observed in nongrowing bacteria suspended in phosphate-buffered saline. While rifampin antagonized the bactericidal effects of ciprofloxacin, ciprofloxacin did not antagonize the bactericidal effects of rifampin. Each antimicrobial prevented the emergence of subpopulations that were resistant to the other.

Paecilomyces sinusitis in an immunocompromised adult patient: case report and review.

A case of fungal sinusitis caused by Paecilomyces lilacinus that was unresponsive to amphotericin B and involved a patient with acute myeloid leukemia is described. Histologic examination of sinus tissue and periorbital bone demonstrated invasion by a fungus with septate hyphae, which was identified in culture as P. lilacinus. The isolate was resistant to amphotericin B but susceptible to itraconazole. The patient responded clinically when itraconazole was added to the treatment regimen. Invasive aspergilar infections are frequently diagnosed by histology. Other fungi such as Fusarium, Pseudallescheria, and Paecilomyces species also produce hyphae in tissue and can be confused with Aspergillus species. However, these pathogens may be resistant to amphotericin B. Since alternative therapy is now available for infections with some of the amphotericin B-resistant fungi, such as P. lilacinus, every effort should be made to recover the fungal pathogen so that effective treatment can be administered.

Improved identification of Staphylococcus aureus using a new agglutination test. Results of an international study.

A new reagent for the identification of Staphylococcus aureus, SLIDEX STAPH-KIT, operates on the principle of a latex and red blood cell combination agglutination: red blood cells are coated with fibrinogen for the detection of clumping factor, and latex particles are sensitized with anti-S. aureus serotype 18 monoclonal antibody for the detection of protein A and antigen 18. French strains belonging to serotype 18 are methicillin-resistant. The performance of this reagent was compared with STAPHYSLIDE and STAPHAUREX in Europe (France, Germany, Italy), in the United States and in Japan using 548 methicillin-resistant S. aureus strains, 392 methicillin-sensitive S. aureus strains, and 441 non-aureus staphylococci. The specificity of the three reagents was equivalent (98.8% for SLIDEX STAPH-KIT, 99.1% for STAPHYSLIDE, 98.1% for STAPHAUREX). SLIDEX STAPH-KIT (97.3%) was more sensitive than STAPHYSLIDE (93.5%) and STAPHAUREX (89.7%) for all S. aureus strains due to a higher rate of identified methicillin-resistant S. aureus strains.

Rapid detection of positive blood cultures with the BACTEC NR-660 does not require first-day subculturing.

An analysis of blood culture data was performed to determine whether subculturing within the first 24 h of incubation decreased the time to detection of positive blood cultures when compared with the routine use of the BACTEC NR-660 system (Johnston Laboratories, Inc., Towson, Md.). During a 9-month period (June 1985 to February 1986), 17,913 blood cultures were received in our laboratory, of which 1,463 (8.2%) became positive. Of the positive cultures, 97% were detected with equal or greater rapidity by the NR-660 system than by visual inspection and first-day blind subculturing. There were 37 delayed positive cultures from which only one isolate (0.07%) was not eventually detected by the NR-660 system. Coagulase-negative staphylococcus was the most frequent isolate among the delayed positive cultures, but only 3 of 15 isolates were known to be clinically significant isolates. The longest delay in detection by the NR-660 system was 6 days for one isolate of Cryptococcus neoformans and one isolate of Klebsiella pneumoniae. Although subculturing may decrease the time to detection of a few cultures, the majority of positive blood cultures were detected faster or with equal speed by the NR-660 system. When the data were evaluated, routine use of the NR-660 system was sufficient for the detection of positive blood cultures and was cost-effective.