Sylviane Chevrier

Comparison of Epidemiological, Clinical, and Biological Features of Invasive Aspergillosis in Neutropenic and Nonneutropenic Patients: A 6-Year Survey

BACKGROUND Invasive aspergillosis is an opportunistic infection that occurs mainly among patients with prolonged neutropenia. Few data are available on invasive aspergillosis in nonneutropenic patients. METHODS The aim of this survey was to compare neutropenic and nonneutropenic patients who had received a diagnosis of invasive aspergillosis at our institution during a 6-year period. RESULTS Among the 88 cases of invasive aspergillosis analyzed here, 12 were histologically proven, 52 were probable, and 24 were possible. Forty-seven percent of cases were diagnosed in the intensive care unit, and 40% were diagnosed in hematology units. Neutropenia was a risk factor for 52 patients (59%), most of whom had hematological or solid malignancies. Among the 36 nonneutropenic patients (41%), the main underlying conditions were steroid-treated chronic obstructive pulmonary disease, asthma, rheumatoid arthritis, giant-cell arteritis, and microvascular disorders; 10 patients were recipients of solid-organ transplants, and 1 patient was seropositive for human immunodeficiency virus. The distribution of proven and probable invasive aspergillosis was similar for neutropenic and nonneutropenic patients. The mortality rate was 71.5% overall and was significantly higher among nonneutropenic patients than among neutropenic patients (89% vs. 60%; P<.05). Compared with neutropenic patients, nonneutropenic patients were significantly less likely to have symptoms of invasive aspergillosis and more likely to have frequent intercurrent pneumonia due to another microorganism. The sensitivity of mycological examination of bronchoalveolar lavage fluid specimens was higher for nonneutropenic patients than for neutropenic patients (85% vs. 58%; P<.05), whereas the sensitivity of antigenemia was the same for the 2 populations (65% vs. 64%). Findings on thoracic computed tomographs were similar, except that segmental areas of consolidation occurred more frequently among neutropenic patients. CONCLUSION This survey at a whole institution underlines the high number of cases of invasive aspergillosis among nonneutropenic patients, with an overall mortality rate that was significantly higher than that for neutropenic patients.

USE OF DNA FINGERPRINTING AND BIOTYPING METHODS TO STUDY A CANDIDA ALBICANS OUTBREAK IN A NEONATAL INTENSIVE CARE UNIT

During a 15-day period, 7 premature infants hospitalized in a neonatal intensive care unit presented with sepsis caused by Candida albicans. The local environment and hands of all 54 persons involved in the intensive care unit were examined for the presence of this organism. Five techniques were used in the analysis in the analysis of the isolates recovered from blood cultures of the children, the hands of personnel and 10 control isolates. The methods used were serotype determination, genetic fingerprinting, morphotyping, resistotyping and killer yeast typing. Morphotyping and genetic fingerprinting proved to be the most discriminatory techniques, and only combined analysis of the results obtained with these various methods allowed the source of the outbreak to be identified. An isolate from the hands of a healthy staff member and isolates from infected children all belonged to the same strain.

Bacterial and Fungal Counts in Hospital Air: Comparative Yields for 4 Sieve Impactor Air Samplers With 2 Culture Media

We compared the yields of 4 recently developed sieve impactor air samplers that meet international standard ISO 14698-1, using 2 growth media (tryptic soy agar and malt extract agar) in real conditions of use. Several hospital sites expected to have different densities of airborne microflora were selected in 2 hospitals. The Samplair MK2, Air Ideal, and Mas-100 samplers yielded higher bacterial counts than did the SAS Super-100 device (P<.05). No significant differences in fungal counts were noted between the 4 devices. The use of malt extract agar in addition to tryptic soy agar significantly improved the fungal yield.

Diagnosis of Pneumocystis jirovecii Pneumonia in Immunocompromised Patients by Real-Time PCR: a 4-Year Prospective Study

ABSTRACT Pneumocystis jirovecii pneumonia (PCP) is a life-threatening infection in immunocompromised patients. Quantitative real-time PCR (qPCR) is more sensitive than microscopic examination for the detection of P. jirovecii but also detects colonized patients. Hence, its positive predictive value (PPV) needs evaluation. In this 4-year prospective observational study, all immunocompromised patients with acute respiratory symptoms who were investigated for PCP were included, totaling 659 patients (814 bronchoalveolar lavage fluid samples). Patients with negative microscopy but positive qPCR were classified through medical chart review as having retained PCP, possible PCP, or colonization, and their clinical outcomes were compared to those of patients with microscopically proven PCP. Overall, 119 patients were included for analysis, of whom 35, 41, and 43 were classified as having retained PCP, possible PCP, and colonization, respectively. The 35 patients with retained PCP had clinical findings similar to those with microscopically proven PCP but lower fungal loads (P < 0.001) and were mainly non-HIV-infected patients (P < 0.05). Although the mean amplification threshold was higher in colonized patients, it was not possible to determine a discriminant qPCR cutoff. The PPV of qPCR in patients with negative microscopy were 29.4% and 63.8% when considering retained PCP and retained plus possible PCP, respectively. Patients with possible PCP had a higher mortality rate than patients with retained PCP or colonization (63% versus 3% and 16%, respectively); patients who died had not received co-trimoxazole. In conclusion, qPCR is a useful tool to diagnose PCP in non-HIV patients, and treatment might be better targeted through a multicomponent algorithm including both clinical/radiological parameters and qPCR results.

Post-Traumatic Course Complicated by Cutaneous Infection with Absidia corymbifera

Abstract Cutaneous mucormycosis is a rare but serious infection in trauma patients. Reported here is the case of a young patient with cutaneous mucormycosis due to Absidia corymbifera probably caused by a soil-contaminated wound. Despite daily surgical debridement and amphotericin B therapy, cure could be achieved only by amputation of the lower limb.

Epidemiology of Trichophyton verrucosum infection in Rennes University Hospital, France: A 12-year retrospective study

Abstract Trichophyton verrucosum is a zoophilic dermatophyte, known as a causative agent of inflammatory mycoses of the skin and the scalp in humans. In this study, we reviewed all cases of T. verrucosum infection diagnosed in our laboratory over a 12‐year period, to determine epidemiological and clinical characteristics. Among 18,340 samples analyzed, 5,186 cultured positive with dermatophytes (2674 patients), of which 64 samples (41 patients) were positive for T. verrucosum. Our data show that there was a strong influence of age on the type of lesion, with children and adults presenting more frequently with tinea capitis and skin infections, respectively (P < .0001). Infection of children and adults resulted more frequently from indirect and direct exposure to cattle, respectively (P < .01). We observed a marked increase of cases over the last 4 years, with a correlation of the number of cases and the mean annual rainfall (P < .05), suggesting that increasing humidity favors cattle infection, and thereby, human infection. Whether this increase is the consequence of climate changes remains to be determined but should be considered.

Performance of Molecular Approaches for Aspergillus Detection and Azole Resistance Surveillance in Cystic Fibrosis

Aspergillus fumigatus triazole resistance is an emerging concern for treating chronically infected/colonized patients. This study sought to evaluate the performance of PCR assays to detect Aspergillus fungi together with azole resistance in sputum samples from cystic fibrosis (CF) patients. In total, 119 sputum samples from 87 CF patients were prospectively processed for Aspergillus detection by means of mycological culture and four qPCR assays, 2 in-house methods and two commercial multiplex real-time PCR assays simultaneously detecting Aspergillus and the most relevant cyp51A gene mutations (MycoGENIE® and AsperGenius®). Azole susceptibility of A. fumigatus isolates was assessed using Etest® method and cyp51A gene mutation were characterized by sequencing. The overall rate of Aspergillus detection with the four qPCR assays ranged from 47.9 to 57.1%, contrasting with 42/119 (35.3%) positive cultures with A. fumigatus. The high sensitivity of PCR on sputum could then contribute to more effective grading of Aspergillus disease in CF patients. Five out of 41 isolated strains (12.2%) exhibited azole-resistant MIC patterns, three of which harbored cyp51A mutations and only 1/3 with the sequence TR34/L98H. Combined with culture, PCR assay achieved high sensitivity Aspergillus screening in CF samples. However, cyp51A targeting was only moderately effective for azole resistance monitoring, while Aspergillus resistance remains of great concern.

Mycoses profondes et transplantation

Resume De nombreux agents fongiques opportunistes sont responsables de mycoses profondes gravissimes en cas d’alteration des defenses de l’hote. La greffe de moelle et les transplantations d’organes solides, de part les protocoles utilises et les maladies de fond traitees, constituent des terrains favorisant ces infections. La premiere difficulte est diagnostique. Elle est due a la biodiversite de ces agents, nombreux genres de levures et de filamenteux, pour lesquels le biologiste doit savoir utiliser les outils de laboratoire necessaires a leur isolement et a leur identification. La seconde difficulte est la prise en charge medicale, qui repose sur une therapeutique adaptee en fonction des indications mycologiques donnees par le biologiste, mais qui repose egalement sur des strategies de prevention, vis-a-vis des reservoirs endogenes de levures, ou du reservoir environnemental de filamenteux.

Infections fongiques systémiques

Les mycoses systemiques sont liees soit a des champignons pathogenes (certains tres rares en Europe de l’Ouest1) soit a des champignons opportunistes de plus en plus nombreux. Ces derniers constituent une complication de plus en plus frequente et redoutable des patients : porteurs d’affections debilitantes : diabete, cirrhose, grande prematurite, dermatoses etendues, brulures, traitements au long cours par corticoides, antibiotiques ou radiotherapie, nouveau-nes, grands prematures; les immunodeprimes essentiellement hemopathes, cancereux, sideens, transplantes d’organe ou de moelle ou, plus rarement, les enfants atteints de deficits immunitaires congenitaux complexes ou acquis selectifs (lymphopenie CD4) 2, 3, 4, 5, 6, 7.