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Background Cryptococcus neoformans causes life-threatening meningitis. A recently introduced lateral flow immunoassay (LFA) to detect cryptococcal antigen (CRAG) is reportedly more rapid and convenient than standard latex agglutination (LA), but has not yet been evaluated in a diagnostic laboratory setting.MethodsOne hundred and six serum, 42 cerebrospinal fluid (CSF), and 20 urine samples from 92 patients with known or suspected cryptococcosis were tested by LA and LFA, and titres were compared. Results were correlated with laboratory-confirmed cryptococcosis. Serial samples were tested in nine treated patients.ResultsTwenty-five of 92 patients had confirmed cryptococcosis; all sera (n = 56) from these patients were positive by LFA (sensitivity 100%, 95% confidence interval (CI) 93.6–100%) compared with 51/56 positive by LA (sensitivity 91.1%, 95% CI 80.7–96.1%). Fifty sera from 67 patients without cryptococcosis tested negative in both assays. While LA yielded more false negative results (5/56) this did not reach statistical significance (p = 0.063). Nine CSF samples from patients with cryptococcal meningitis yielded positive results using both assays while 17/18 urine samples from patients with cryptococcosis were positive by the LFA. The LFA detected CRAG in C. gattii infection (n = 4 patients). Agreement between titres obtained by both methods (n = 38 samples) was imperfect; correlation between log-transformed titres (r) was 0.84. Turn-around-time was 20 minutes for the LFA and 2 h for LA. The cost per qualitative sample was 18USD and 91 USD, respectively and per quantitative sample was 38USD and 144USD, respectively.ConclusionsQualitative agreement between the LFA and LA assays performed on serum and CSF was good but agreement between titres was imperfect. Ease of performance of the LFA and the capacity for testing urine suggest it has a role in the routine laboratory as a rapid diagnostic test or point-of-care test.

Respiratory samples from cystic fibrosis outpatients were cultured on Sabouraud's dextrose agar (SABD) containing antibiotics, Mycosel, and Scedosporium-selective medium (SceSel؉). Thirty-two (14.7%) of 218 specimens from 11/69 (15.9%) patients yielded a Scedosporium sp., most frequently Scedosporium aurantiacum (17/218). Scedosporium was recovered on SceSel؉, Mycosel, and SABD from 90.6%, 50.0%, and 46.9% of the specimens tested, respectively.Opportunistic molds are increasingly isolated in respiratory specimens from children and adults with cystic fibrosis (CF) (17). Scedosporium species are the second most frequently recovered fungi, after Aspergillus fumigatus (4). Although invasive scedosporiosis is reportedly rare in CF prior to lung transplantation (11), colonization may be a risk factor for invasive disease posttransplantation, with associated high mortality (14,19,(21)(22)(23). The impact of airway colonization by Scedosporium spp. on respiratory function has not been studied; nevertheless, as Scedosporium spp. are resistant to many antifungal agents, colonization may be a relative contraindication to transplantation (18).Isolation of multiple fungi from respiratory specimens is frequent (19). The prevalence of non-Aspergillus molds may be underestimated due to overgrowth of Aspergillus spp. on routine media (4). A medium (SceSelϩ) containing the selective antifungal agents dichloran and benomyl has been described for the recovery of Scedosporium from environmental samples (16,20), but its utility in detecting Scedosporium spp. in clinical specimens has not been determined. No commercial preparation is available. Scedosporium spp. have been identified previously in respiratory specimens from 8.6 to 10% of CF patients (4, 24). These data were published prior to recent taxonomic reassignments of Scedosporium spp. (9, 10), and selective media were not used. We therefore compared the performance of two general media and one selective medium for the isolation of Scedosporium spp. from respiratory specimens and prospectively investigated the frequency and species distribution of Scedosporium in CF patients. Plates were incubated at 30°C in air and examined twice weekly for 28 days. Suspicious colonies were identified to the species level (Aspergillus and Scedosporium spp.) or the genus level (other molds) by standard morphological/ phenotypic methods (7, 9, 10). Scedosporium strains were identified as Scedosporium prolificans, S. aurantiacum, or S. apiospermum by restriction fragment length analysis of the internal transcribed spacer (ITS) region (8). ITS sequence analysis was performed on all S. apiospermum isolates and selected S. aurantiacum isolates (8).Samples (n ϭ 218) were received from 69 patients. Filamentous fungi were detected in 142 samples (65.1%) from 56 patients (81.2%; Table 1). The majority of the fungi (83.9%) were recovered following 6 days of incubation, and 95.1% were recovered following 10 days. Aspergillus spp. were the most frequently recovered, with A. fumigatus isolated in 45.4% of t...

Invasive fungal infections are an important cause of infectious morbidity. Nonculture-based methods are increasingly used for rapid, accurate diagnosis to improve patient outcomes. New and existing DNA amplification platforms have high sensitivity and specificity for direct detection and identification of fungi in clinical specimens. Since laboratories are increasingly reliant on DNA sequencing for fungal identification, measures to improve sequence interpretation should support validation of reference isolates and quality control in public gene repositories. Novel technologies (e.g., isothermal and PNA FISH methods), platforms enabling high-throughput analyses (e.g., DNA microarrays and Luminex xMAP) and/or commercial PCR assays warrant further evaluation for routine diagnostic use. Notwithstanding the advantages of molecular tests, serological assays remain clinically useful for patient management. The serum Aspergillus galactomannan test has been incorporated into diagnostic algorithms of invasive aspergillosis. Both the galactomannan and the serum beta-D-glucan test have value for diagnosing infection and monitoring therapeutic response.

dWe developed an Australian database for the identification of Aspergillus, Scedosporium, and Fusarium species (n ‫؍‬ 28) by matrix-assisted laser desorption ionization؊time of flight mass spectrometry (MALDI-TOF MS). In a challenge against 117 isolates, species identification significantly improved when the in-house-built database was combined with the Bruker Filamentous Fungi Library compared with that for the Bruker library alone (Aspergillus, 93% versus 69%; Fusarium, 84% versus 42%; and Scedosporium, 94% versus 18%, respectively). Rapid, accurate mold identification is important due to the widening spectrum of pathogens and species-specific differences in antifungal susceptibility (1-3). Matrix-assisted laser desorption ionizationϪtime of flight mass spectrometry (MALDI-TOF MS) has proven useful, but mold identification remains challenged by the limited access to validated purpose-built databases that are necessary because of small species and strain representations in commercial libraries (4-16).Given the prior poor performance of the Bruker Filamentous Fungi Library v1.0 (Bruker Daltonics, Bremen, Germany) for mold identification using the manufacturer-recommended broth-based protein extraction methods (in our laboratory Ͼ50% of isolates were not identified; internal data) and because the geographic generalizability of in-house-built databases is not yet known, we hypothesized that a MS library of molds relevant to our region (17-21) will improve identification. Here, we constructed an in-house database containing 117 strains (see Table S1 in the supplemental material) covering 28 species of Aspergillus, Scedosporium, and Fusarium encountered in Australia. Challenge isolates (also n ϭ 117; 21 species) comprising 55 Aspergillus, 45 Fusarium, and 17 Scedosporium clinical strains (Table 1) were then used to assess the performance of the Bruker library alone versus that of the Bruker library supplemented with the in-house library for species identification.All isolates were identified using phenotypic methods (22) with definitive identification by DNA sequencing of the internal transcribed spacer (ITS) (all isolates), ␤-tubulin (Aspergillus and Scedosporium spp.), and partial elongation factor-1alpha (EF-1␣) (to identify Fusarium to the species complex level) gene regions (23)(24)(25)(26). Sequence data were analyzed against the Centraalbureau voor Schimmelkultures (http://www.cbs.knaw.nl/Collections /BioloMICSSequences.aspx?fileϭall), International Society for Human and Animal Mycology ITS (http://its.mycologylab.org/), and Fusarium-ID (http://www.fusariumdb.org/index.php) databases, and species were assigned using published criteria (27).Protein extraction for MALDI-TOF MS was performed as previously described (11). The Bruker bacterial test standard (Bruker Daltonics) was used for calibration and Aspergillus ustus CBS 261.67T scoring of Ն2.00 was required for quality extraction and spectra acceptability (11). The in-house database was constructed using published protocols (11, 28) with 20 to 25 quality spe...

The high sensitivity of antidoping detection tests creates the possibility of inadvertent doping due to an athlete's unknowing ingestion of contaminated environmental sources such as dietary supplements, food, or drinks. Recently, athletes denying use of a prohibited substance have claimed that the positive antidoping tests was due to exchange of bodily fluids with a nonathlete partner using a prohibited substance.Measurement of drugs in semen is largely limited to one or very few samples due to the inaccessibility of sufficiently frequent semen samples for detailed pharmacokinetics. An emerging issue in semen drug measurements is that semen samples may contain residual urine from ejaculation left in the urethra; however, the urine content in semen samples has not been studied. In the present study, we employed concurrent creatinine measurements in urine and seminal plasma to determine the urine content of semen samples.

Disseminated histoplasmosis and nocardiosis typically affect immunocompromised hosts. We report a case of gastrointestinal and adrenal histoplasmosis, presenting as protein-losing enteropathy and hypogammaglobulinaemia, coincident with Nocardia infection, in a HIV-negative patient in whom a specific immunological defect could not be identified. Clinicians in areas of non-endemicity should be vigilant for rare manifestations of histoplasmosis.

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