RESUMO
We reviewed the performance of a panfungal ITS-2 PCR and Sanger sequencing assay performed on 88 FFPE specimens at The Hospital for Sick Children (Toronto, Canada) in 2019. A potential fungal pathogen was identified by ITS PCR in 62.7 and 2.9% of positive and negative direct slide examination of tissue specimens, respectively. ITS amplicons were detected in 87/88 specimens, with 53/88 (60.2%) considered as 'positive-contaminants' and 34/88 (38.6%) as 'positive-potential pathogen' upon sequencing. Potential pathogens included Blastomyces dermatitidis (17.1%), Cryptococcus neoformans (17.1%), Histoplasma capsulatum (14.3%) and Mucormycetes (11.4%). Laboratories should only perform ITS PCR on FFPE tissues if fungal elements have been confirmed on histopathology slides. LAY SUMMARY: In this study, we examined how well a DNA-based test could detect DNA from fungi in archived human biopsy tissues. The best performance was achieved if fungi were seen in the tissue under a microscope before being tested. Our results indicate that we should only use this test if these conditions are met.
Assuntos
Formaldeído , Histoplasma , Animais , DNA Fúngico/genética , Histoplasma/genética , Inclusão em Parafina/veterinária , Reação em Cadeia da Polimerase/veterinária , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: The role of respiratory viruses in cystic fibrosis (CF) exacerbations is incompletely understood. METHODS: Cross-sectional study of CF children with a pulmonary exacerbation. Mid-turbinate swabs were tested by a direct immunofluorescent antibody assay and a multiplex PCR panel (ResPlex II v2.0, Qiagen). Resplex II was also applied to sputum or throat swab samples. Pulmonary function tests and quality of life and severity scores were recorded. Sputum cell counts, bacterial density and cytokines were measured. RESULTS: 26/43 (60.5%) subjects tested positive for at least one respiratory virus by any diagnostic method applied to any sample type. Virus-positive patients were younger (p=0.047), more likely to be male (p=0.029), and had higher CF clinical severity (p=0.041) and lower quality of life (physical) scores (p=0.023) but similar IL-8, neutrophil percentage and elastase levels. CONCLUSIONS: Compared to non-viral exacerbations, viral-related exacerbations were associated with worse severity and quality of life scores but similar pulmonary inflammation.
Assuntos
Fibrose Cística , Infecções Respiratórias , Viroses , Vírus , Adolescente , Fatores Etários , Bactérias/classificação , Bactérias/isolamento & purificação , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/fisiopatologia , Canadá/epidemiologia , Criança , Pré-Escolar , Coinfecção/epidemiologia , Estudos Transversais , Fibrose Cística/epidemiologia , Fibrose Cística/fisiopatologia , Fibrose Cística/psicologia , Fibrose Cística/virologia , Feminino , Humanos , Masculino , Faringe/microbiologia , Prevalência , Qualidade de Vida , Testes de Função Respiratória , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/fisiopatologia , Infecções Respiratórias/virologia , Índice de Gravidade de Doença , Fatores Sexuais , Viroses/diagnóstico , Viroses/epidemiologia , Viroses/fisiopatologia , Vírus/classificação , Vírus/isolamento & purificaçãoRESUMO
We report the case of a 15-year old with acute myeloid leukemia who developed breakthrough invasive fungal rhinitis. The fungus was identified as Alternaria infectoria by polymerase chain reaction (PCR) and successfully treated by surgical excision and combination antifungal therapy, emphasizing the utility of fungal PCR in timely diagnosis of invasive fungal infections.