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Background: In-house real-time PCR (qPCR) is increasingly used to diagnose the so-called endemic mycoses as commercial assays are not widely available. Objectives: To compare the performance of different molecular diagnostic assays for detecting Histoplasma capsulatum and Coccidioides spp. in five European reference laboratories. Methods: Two blinded external quality assessment (EQA) panels were sent to each laboratory that performed the analysis with their in-house assays. Both panels included a range of concentrations of H. capsulatum (n = 7) and Coccidioides spp. (n = 6), negative control and DNA from other fungi. Four laboratories used specific qPCRs, and one laboratory a broad-range fungal conventional PCR (cPCR) and a specific cPCR for H. capsulatum with subsequent sequencing. Results: qPCR assays were the most sensitive for the detection of H. capsulatum DNA. The lowest amount of H. capsulatum DNA detected was 1-4 fg, 0.1 pg and 10 pg for qPCRs, specific cPCR and broad-range cPCR, respectively. False positive results occurred with high concentrations of Blastomyces dermatitidis DNA in two laboratories and with Emergomyces spp. in one laboratory. For the Coccidioides panel, the lowest amount of DNA detected was 1-16 fg by qPCRs and 10 pg with the broad-range cPCR. One laboratory reported a false positive result by qPCR with high load of Uncinocarpus DNA. Conclusion: All five laboratories were able to correctly detect H. capsulatum and Coccidioides spp. DNA and qPCRs had a better performance than specific cPCR and broad-range cPCR. EQAs may help standardise in-house molecular tests for the so-called endemic mycoses improving patient management. This work was supported by research project PI21CIII/00007 from Spanish Fondo de Investigaciones Sanitarias of the Instituto de Salud Carlos III Sí

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM Introduction In-house real-time PCR (qPCR) is increasingly used for the diagnosis of endemic mycoses and diverse assays are in use in specialized laboratories. External quality control is currently lacking. Objective To compare the performance of different molecular detection protocols for the detection of Histoplasma capsulatum and Coccidioides spp. in a multicenter study involving five European laboratories. Methods Two test sample panels were sent to each laboratory which performed the analysis with their in-house assays. Recipients were blinded to sample content. The Histoplasma-panel included 14 samples representing a range of concentrations of Histoplasma DNA (n = 7), as well as a negative control and DNA from other fungi to test for specificity (Paracoccidioides lutzii n = 1; Blastomyces dermatitidis n = 1; Aspergillus fumigatus n = 1; Emergomyces spp. n = 2, and Candida albicans n = 1). The Coccidioides-panel included 10 samples representing a range of DNA concentrations of Coccidioides posadasii (n = 6), as well as a negative control and DNA from other fungi to test specificity (Uncinocarpus reesii n = 1; Trichophyton violaceum n = 1; and Candida albicans n = 1). Regarding techniques used, four laboratories used Histoplasma qPCRs, and one laboratory a conventional PCR and a broad-range PCR (brPCR) for fungal DNA. Four laboratories used different Coccidioides qPCRs and one laboratory a brPCR to detect Coccidioides DNA. Results Concerning the Histoplasma panel, qPCR assays were the most sensitives and agreement in the lowest detected amount of Histoplasma DNA was very suitable, ranging from 1 pg to 4 pg [ Conclusion Specific protocols based on qPCR showed better sensitivity than conventional and brPCR. These methods are useful for the rapid and sensitive detection Histoplasma and Coccidioides. Application of these tests on clinical samples may speed up diagnosis and potentially limit laboratory exposure to these fungi. Comparisons of in-house tests are essential to assess the performance and detect potential cross-reactivities and achieve a consensus.

In times of massive biodiversity loss and ongoing environmental crises, it is extremely important to ensure long-term conservation efforts of threatened species like Eurasian otters (Lutra lutra). To gain insights into the status of Northern Germany’s otter population, 92 otters found dead in Schleswig-Holstein between 2015−2020 were collected and underwent detailed dissection with the aim to establish a monitoring program for this population. Examinations followed a protocol especially designed for otters, including various biological data assessments and extended sampling. The finding sites showed a clear concentration in the Continental region. Seasonal concentration differed among the years, yet peaks were seen from fall to winter. Overall, more males than females were found, although this differed among the years. The majority of otters that could be aged were between 1–3 years. Placental scars and pregnancy were recorded in only few females. Nutritional status was good in most cases. Infectious diseases found included Vagococcus lutrae, Toxoplasma gondii, and Emmonsia spp. A major cause of death was roadkill. Known sample bias in studies focusing on roadkill was considered in the finding interpretation. Continuation of the population health investigations is mandatory to analyze potential trends and to establish an actual monitoring program for Eurasian otters in Schleswig-Holstein.