Mise en évidence de mâles hétérozygotes chez l'hyménoptère Diadromus pulchellus (Ichneumonide)

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Levels of (1→3)-β-D-glucan, Candida mannan and Candida DNA in serum samples of pediatric cancer patients colonized with Candida species

<p>Abstract</p> <p>Background</p> <p>Surveillance cultures may be helpful in identifying patients at increased risk of developing invasive candidiasis. However, only scant information exists on the effect of <it>Candida </it>colonization on serum levels of diagnostic biomarkers. This prospective surveillance study determined the extent of <it>Candida </it>colonization among pediatric cancer patients and its possible impact on serum levels of (1-3)-β-D-glucan (BDG), <it>Candida </it>mannan and <it>Candida </it>DNA.</p> <p>Methods</p> <p>A total of 1075 swabs originating from oropharynx (n = 294), nostrils (n = 600), rectum (n = 28), groin (n = 50), ear (n = 54), and axilla (n = 49) of 63 pediatric cancer patients were cultured for the isolation of <it>Candida </it>spp. Patients yielding <it>Candida </it>spp. from any sites were considered as colonized. Serum samples were collected from patients at the time of first surveillance culture for detection of BDG by Fungitell kit and <it>Candida </it>mannan by Platelia <it>Candida </it>Ag. <it>Candida </it>DNA was detected by using panfungal primers and identification was carried out by using species-specific primers and DNA sequencing.</p> <p>Results</p> <p>Seventy-five (7.6%) swab cultures from 35 (55.5%) patients yielded <it>Candida </it>spp. These isolates included <it>C. albicans </it>(n = 62), <it>C. dubliniensis </it>(n = 8), <it>C. glabrata </it>and <it>C. tropicalis </it>(n = 2 each) and <it>C. krusei </it>(n = 1). Eleven patients were colonized at three or more sites. Eight of 36 serum samples from 6 colonized patients yielded BDG values higher than the currently recommended cut-off value of ≥80 pg/ml. However, none of the serum samples yielded <it>Candida </it>mannan levels ≥0.5 ng/ml and PCR test for <it>Candida </it>DNA was also negative in all the serum samples of colonized patients. During the study period, only two colonized patients subsequently developed candidemia due to <it>C. tropicalis</it>. Besides positive blood cultures, <it>C. tropicalis </it>DNA, BDG and <it>Candida </it>mannan were also detected in serum samples of both the patients.</p> <p>Conclusions</p> <p>The present study demonstrates that while mucosal colonization with <it>Candida </it>species in pediatric cancer patients is common, it does not give rise to diagnostically significant levels of <it>Candida </it>mannan or <it>Candida </it>DNA in serum specimens. However, BDG values may be higher than the cut-off value in some pediatric patients without clinical evidence of invasive <it>Candida </it>infection. The study suggests the utility of <it>Candida </it>mannan or <it>Candida </it>DNA in the diagnosis of invasive candidiasis, however, the BDG levels in pediatric cancer subjects should be interpreted with caution.</p

Primary cytomegalovirus infection with accompanying Pneumocystis jiroveci pneumonia in a patient with large-vessel vasculitis

A 70 year-old female patient presented with fever, nausea and dyspnea. She had been receiving immunosuppressive therapy with methotrexate and prednisone for large-vessel vasculitis. The patient was shown to have coexistent Pneumocystis jiroveci pneumonia and primary cytomegalovirus (CMV) infection with presumed CMV pneumonitis and colitis. To our knowledge, this is the first case report on the occurrence of combined primary cytomegalovirus and Pneumocystis jiroveci infection in a patient with vasculitis. It illustrates the importance of being aware of the possibility of combined opportunistic infections in patients with rheumatologic diseases

Bacterial lipopolysaccharides variably modulate in vitro biofilm formation of Candida species

The objective of this study was to evaluate the effect of the bacterial endotoxin LPS on Candida biofilm formation in vitro. The effect of the LPS of Pseudomonas aeruginosa, Klebsiella pneumoniae, Serratia marcescens and Salmonella typhimurium on six different species of Candida, comprising Candida albicans ATCC 90028, Candida glabrata ATCC 90030, Candida krusei ATCC 6258, Candida tropicalis ATCC 13803, Candida parapsilosis ATCC 22019 and Candida dubliniensis MYA 646, was studied using a standard biofilm assay. The metabolic activity of in vitro Candida biofilms treated with LPS at 90 min, 24 h and 48 h was quantified by XTT reduction assay. Viable biofilm-forming cells were qualitatively analysed using confocal laser scanning microscopy (CLSM), while scanning electron microscopy (SEM) was employed to visualize the biofilm structure. Initially, adhesion of C. albicans was significantly stimulated by Pseudomonas and Klebsiella LPS. A significant inhibition of Candida adhesion was noted for the following combinations: C. glabrata with Pseudomonas LPS, C. tropicalis with Serratia LPS, and C. glabrata, C. parapsilosis or C. dubliniensis with Salmonella LPS (