Beta-D-Glucan for Diagnosing Pneumocystis Pneumonia: a Direct Comparison between the Wako beta-Glucan Assay and the Fungitell Assay

Measuring serum beta-d-glucan (BDG) is a useful tool for supporting a quantitative PCR (qPCR)-based diagnosis of suspected Pneumocystis pneumonia (PCP) with bronchoalveolar lavage (BAL) fluid. Since the 2000s, the Fungitell assay was the only BDG assay which was FDA cleared and Conformité Européenne (CE) marked. However, the Wako β-glucan test was also recently CE marked and commercialized. We analyzed archived sera from 116 PCP cases (who were considered to have PCP based on compatible clinical and radiological findings plus a BAL fluid qPCR threshold cycle value of ≤28) and 114 controls (those with a BAL fluid qPCR threshold cycle value of >45 and no invasive fungal infection) using the Fungitell and Wako assays in parallel and assessed their diagnostic performance using the manufacturer's proposed cutoffs of 80 pg/ml and 11 pg/ml, respectively. We found the Wako assay to be more specific (0.98 versus 0.87, P < 0.001) and the Fungitell assay to be more sensitive (0.78 versus 0.85, P = 0.039) at the proposed cutoffs. Overall performance, as determined by the area under the receiver operating characteristic curve, was similar for both assays. We determined a new Wako assay cutoff (3.616 pg/ml) to match the sensitivity of the Fungitell assay (0.88 at a cutoff of ≥60 pg/ml). Using this newly proposed cutoff, the specificity of the Wako assay was significantly better than that of the Fungitell assay (0.89 versus 0.82, P = 0.011). In conclusion, the Wako assay performed excellently compared to the Fungitell assay for the diagnosis of presumed PCP based on qPCR. In addition, contrary to the Fungitell assay, the Wako assay allows for single-sample testing with lower inter- and intrarun variability. Finally, we propose an optimized cutoff for the Wako assay to reliably exclude PCP.status: publishe

Increase of ST19A invasive pneumococcal disease in young children after the switch from PCV13 to PCV10 in Belgium.

oral presentationstatus: publishe

Serum symmetric dimethylarginine in older dogs: Reference interval and comparison of a gold standard method with the ELISA

Abstract Background Serum symmetric dimethylarginine (SDMA) is used to screen for renal dysfunction in dogs. The gold standard technique for measuring SDMA, liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) is not widely available. Age‐specific reference intervals for SDMA in older dogs are lacking. Objectives Prospective study in older dogs to validate a commercially available LC‐MS/MS method for SDMA, compare SDMA concentrations with concentrations measured using ELISA and obtain a reference interval (RI) for older dogs using both methods. Animals Client‐owned older dogs undergoing health screening. Methods The LC‐MS/MS method was analytically validated (limit of detection, precision, and linearity). Serum was sent cooled overnight for ELISA or was frozen at −80°C until batch analysis using LC‐MS/MS. Results of LC‐MS/MS and ELISA were compared and RIs for older dogs were calculated according to international guidelines. Results The LC‐MS/MS method showed good linearity (r2 = .99) and precision (coefficient of variation <10%), with a laboratory RI between 8.0 and 14.0 μg/dL. Paired measurements were available from 118 different dogs. Median SDMA concentration were 9.4 (range, 5.0‐21.2) using LC‐MS/MS and 12.0 (range, 5.0‐22.0) μg/dL using ELISA. Both methods significantly differed with a mean difference of 2.2 μg/dL. The RI for older dogs for LC‐MS/MS was 4.4‐15.0 μg/dL, and for ELISA was 6.4‐17.4 μg/dL. Conclusions and Clinical Importance The ELISA provided significantly higher SDMA concentrations compared to the validated LC‐MS/MS method, indicating the need for device‐ or assay‐specific RI. The obtained age‐specific RI for SDMA is considerably higher in older dogs compared to the general laboratory RI

A 5-year survey of dermatophytes strains circulating in Belgium

Objectives Dermatophytosis refers to superficial fungal infections of keratinized tissues caused by keratinophilic dermatophytes. They are the most common cause of superficial fungal infections worldwide. Epidemiological studies regarding dermatophytes infections have been conducted in several countries and differences in the incidence and in etiological agents have been reported. That is why national surveillance of circulating strains causing dermatophytosis is critical. The National Reference Center (NRC) for mycoses conducted a survey on dermatophytes strains circulating in Belgium from 2012 to 2016. The present study was performed to assess the profile of dermatophytosis and to identify the species involved. Methods The Belgian NRC for mycoses (Leuven and Liège) collected 14227 strains between January 2012 and December 2016. The strains were obtained from clinically suspected fungal infections of skin, hair and nails. Strains were collected from Belgian laboratories in order to confirm the fungal identification which was performed by microscopy and in case of doubt by ITS sequencing. Results Among the 14227 samples collected, 6248 were identified as dermatophytes (44%). Trichophyton rubrum was the most prevalent species accounting for 61,3% (n=3820) of the strains collected from all sources, followed by T. mentagrophytes complex (19,2%, n=1199) according to the ancient classification (including T. interdigitale, T. benhamiae and T. mentagrophytes). Other less prevalent species were also recorded: M. audouinii (n=507, 8,1%), M. canis (n=210, 3,3%), T. tonsurans (n= 140, 2,2%), T. violaceum (n=133, 2,1%), T. soudanense (n=125, 2%), M. praecox (n=60, 0,96%) and E. floccosum (n=19, 0,3%) for the main ones. Our data show the predominance of anthropophilic species causing tinea capitis especially M. audouinii responsible for 43,4% (n=303/716) of hair/scalp infection with an increasing number from 2014 to 2016. Trichophyton soudanense, rarely observed in Belgium in the past, is an emerging agent of tinea capitis particularly since 2013, accounting for 11,3% (n=81) of the cases during the 5-year study period. Zoophilic strains such as M. canis which were well represented in the past epidemiology of tinea capitis are decreasing accounting for only 8,8% (n=63) of hair/scalp infection. Finally, our data confirm the high prevalence of T. rubrum as the main etiologic agent of onychomycosis (78,1%, n=3094/3968) followed by T. mentagrophytes complex (18,8%, n=743/3968). Both latter strains were also responsible for the majority of skin infections as they were isolated respectively in 46,2% (n=693/1612) and 21,7% (n=348/1612) of skin samples. Conclusions The present epidemiological survey provides recent data on the prevalence of all dermatophytes circulating in Belgium. Analyzing such data is critical for the establishment of measures for prevention and control of dermatophytes infections. Our study confirms the predominance of T. rubrum followed by species from the ancient T. mentagrophytes complex (T. interdigitale + T. benhamiae) in the Belgian population. This survey highlights also the persistent predominance of M. audouinii and the emergence of T. soudanense as causative agents of tinea capitis

Epidémiologie et aspects cliniques des candidémies en Belgique: étude prospective nationale (Etude TANSIR)

Objectives The aim of this multicenter study was to gather epidemiological data on candidemia in the Belgian population. Another goal was to determine the time in real life setting for reporting to the treating physicians of the species involved and its antifungal susceptibility. Methods Prospective study in 29 Belgian hospitals. From March 1st, 2013 till February 28, 2014 the first Candida isolate from each episode of candidemia was included. Identification and susceptibility testing were performed according to local procedures and isolates were sent to the National Reference Lab with a completed case report form. Species identification was checked by MALDI-TOF mass spectrometry (MS) and ITS sequencing in case no reliable identification was obtained by MS. Antifungal susceptibility testing was performed according to EUCAST guidelines. The total number of patient admissions and hospitalization days during the study period was retrieved from each hospital. Results 341 isolates were retrieved from 325 patients (53.2% male, median age 66 years, range 1-94 years) admitted to the ICU (34.4%), medical wards (30.8%), surgical wards (15.2%), onco-haematology (10.6%), pediatrics (3.0%), neonatology (1.7%) and other wards (4.3%). The mean incidence rate of candidemia was 0.42 per 1,000 admissions (range 0.07 to 1.44) and 0.60 per 10,000 patient days (range from 0.11 to 2.03). Candida albicans was the main cause of candidemia (51.9%), followed by Candida glabrata (26.7%), Candida parapsilosis (9.9%), Candida tropicalis (4.4%), Candida guilliermondii (2.6%), Candida dubliniensis (1.5%), Candida lusitaniae (1.2%), Candida krusei (1.2%) and Candida metapsilosis (0.6%). Overall resistance to fluconazole was 6.7% and to anidulafungin 0.6% (2 C. glabrata isolates were echinocandin resistant). Resistance to amphotericin B was detected in 1 C. tropicalis isolate, all C. albicans, C. glabrata and C. parapsilosis isolates remained susceptible to this drug. Resistance to fluconazole ranged from 3.5% in C. albicans, 8.6% in C. glabrata, 5.6% in C. parapsilosis to 35.7% (5/14 isolates) in C. tropicalis. These five C. tropicalis isolates showed cross resistance to voriconazole and posaconazole. MIC values for caspofungin ranged from 8mg/L, with MIC50 of 0.06mg/L and MIC90 of 0.25mg/L. The median time between blood sampling and positivity of the blood culture bottle was 37h07min (Q1-Q3: 25h42min-54h28min). The median time between blood culture positivity and reporting of isolate identification and susceptibility to the treating physician was 29h58min (Q1-Q3: 23h21min-40h34min) and 59h34min (Q1-Q3: 48h28min-75h20min) respectively. Conclusions A large variation in the incidence of candidemia among Belgian hospitals was observed. Resistance to azole drugs remained low but emerging resistance to these drugs among C. tropicalis was noted. Resistance to echinocandins remains rare in Belgian Candida isolates. These data will be further analyzed in order to evaluate the influence of the identification and susceptibility testing method on the time to report results to the treating physicians.TANSI