Assessment of performance and comparison of three commercial HDV RNA detection assays: implications for diagnosis and treatment monitoring.

Objectives: Precise HDV-RNA detection and quantification are pivotal for diagnosis and monitoring of response to newly approved treatment. We evaluate the performance of three HDV RNA detection and quantification assays. Methods: Hepatitis Delta RT-PCR system kit, EurobioPlex HDV assay, and RoboGene HDV RNA Quantification kit 2.0 were used for testing 151 HBsAg-positive samples, 90 HDV-RNA negative and 61 HDV-RNA positive. We also evaluated serial dilutions of the WHO international standard for HDV, PEI 7657/12. All HDV-RNA positive samples were genotyped using a next-generation sequencing strategy. Results: Qualitative results indicated a 100% concordance between tests. Quantitative results correlated well, r2 = 0.703 (Vircell-vs-Eurobio), r2 = 0.833 (Vircell-vs-RoboGene), r2 = 0.835 (Robogene-vs-Eurobio). Bias index was 2.083 (Vircell-vs-Eurobio), -1.283 (Vircell-vs-RoboGene), and -3.36 (Robogene-vs-Eurobio). Using the WHO IS, Vircell overestimated the viral load by 0.98 log IU/mL, Eurobio by 1.46 log IU/mL, and RoboGene underestimated it by 0.98 log IU/mL. Fifty-nine samples were successfully genotyped (Genotype 1, n=52; Genotype 5, n=7; Genotype 6, n=1), with similar results for correlation and bias. Conclusion: This study underscores the necessity of using reliable HDV-RNA detection and quantification assays, as evidenced by the high concordance rates in qualitative detection and the observed variability in quantitative results. These findings highlight the importance of consistent assay use in clinical practice to ensure accurate diagnosis and effective treatment monitoring of HDV infection.

[Fungemia due to Trichosporon asahii in a patient with hematological malignancy]. / Fungemia por Trichosporon asahii en un paciente con neoplasia hematológica.

BACKGROUND: Trichosporonosis is an opportunistic infection caused by the genus Trichosporon. The majority of cases of invasive trichosporonosis occurs in immunocompromised individuals. CASE REPORT: We describe a case of disseminated infection by Trichosporon asahii in a hematology patient. A 52-year-old man diagnosed with acute lymphoblastic leukemia developed a febrile episode during the third cycle of the induction chemotherapy. The blood cultures were positive after 24h incubation, showing elongated structures compatible with fungal elements in the Gram stain. The identification of the fungus as Trichosporon asahii was carried out by the assimilation of compounds of carbon and the amplification and sequencing of the D1/D2 domain and the internal transcribed spacer of the ribosomal DNA. The fungus was also isolated from the pustular lesions that the patient had in the chest. After treatment with amphotericin B, the patient progressed satisfactorily. CONCLUSIONS: Trichosporon asahii is an emergent pathogen in immunosupressed patients and its presence should not be considered as colonization, as there is risk of invasive infection.