Rhino-orbito-cerebral mucormycosis caused by Rhizopus microsporus var. microsporus in a diabetic patient with COVID-19

Abstract COVID-19 disease caused by the SARS-CoV-2 coronavirus causes a wide range of clinical manifestations, ranging from mild to severe, with the main ones affecting the respiratory tract, such as pneumonia. In patients with greater severity, the high frequency of bacterial and fungal coinfection stands out, a situation related both to the patient's pre-existing comorbidities and due to the hospitalization itself. Cases of mucormycosis associated with COVID-19 were highlighted in the lay and scientific media, with the increase in mycosis cases being directly and indirectly attributed to the viral infection. This report describes a case of rhino-orbito-cerebral mucormycosis in a diabetic patient hospitalized for COVID-19, whose diagnosis was confirmed by identifying the agent Rhizopus microsporus var. microsporus through culture for fungi and PCR examination.

Significant performance variation among PCR systems in diagnosing congenital toxoplasmosis in São Paulo, Brazil: analysis of 467 amniotic fluid samples

INTRODUCTION: Performance variation among PCR systems in detecting Toxoplasma gondii has been extensively reported and associated with target genes, primer composition, amplification parameters, treatment during pregnancy, host genetic susceptibility and genotypes of different parasites according to geographical characteristics. PATIENTS: A total of 467 amniotic fluid samples from T. gondii IgM- and IgG-positive Brazilian pregnant women being treated for 1 to 6 weeks at the time of amniocentesis (gestational ages of 14 to 25 weeks). METHODS: One nested-B1-PCR and three one-round amplification systems targeted to rDNA, AF146527 and the B1 gene were employed. RESULTS: Of the 467 samples, 189 (40.47 percent) were positive for one-round amplifications: 120 (63.49 percent) for the B1 gene, 24 (12.69 percent) for AF146527, 45 (23.80 percent) for both AF146527 and the B1 gene, and none for rDNA. Fifty previously negative one-round PCR samples were chosen by computer-assisted randomization analysis and re-tested (nested-B1-PCR), during which nine additional cases were detected (9/50 or 18 percent). DISCUSSION: The B1 gene PCR was far more sensitive than the AF146527 PCR, and the rDNA PCR was the least effective even though the rDNA had the most repetitive sequence. Considering that the four amplification systems were equally affected by treatment, that the amplification conditions were optimized for the target genes and that most of the primers have already been reported, it is plausible that the striking differences found among PCR performances could be associated with genetic diversity in patients and/or with different Toxoplasma gondii genotypes occurring in Brazil. CONCLUSION: The use of PCR for the diagnosis of fetal Toxoplasma infections in Brazil should be targeted to the B1 gene when only one gene can be amplified, preferably by nested amplification with primers B22/B23.

Radiometric detection of metabolic activity of Paracoccidioides brasiliensis and its susceptibility to amphotericin B and diethylstilbestrol

A paracoccidiodomicose (blastomicose sul-americana) é uma doença sistêmica muito mais freqüente no sexo masculino, causada pelo fungo dimórfico Paracoccidioides brasiliensis. Um sistema radiométrico foi utilizado para estudar a atividade metabólica e o efeito de drogas sobre este fungo "in vitro". A forma Y do fungo, cultivada em Sabouraud líquido, foi inoculada em frascos estéreis contendo o meio aeróbio 6B, juntamente com 2,0 uCi de substâncias marcadas com carbono-14. Frascos-controle, preparados da mesma foram inoculados com fungos autoclavados. Para estudar os efeitos da anfotericina B (AB) (0,1 e 10 microng/ml) e do dietilestilbestrol (DEB) (1,5 e 10 microng/ml), controles adicionais foram preparados, contendo fungos viáveis mas näo a droga. Todos os frascos foram incubados a 35-C e o metabolismo medio diariamente com uma máquina Bactec. A produçäo de CO2 pelo P.brasiliensis foi lenta e pôde ser acompanhada por 50 dias. Concentraçöes de 10 microng/ml de AB e 5 microng/ml de DEB inibiram o metabolismo e tiveram efeito fungicida. Os resultados com DEB poderiam explicar a baixa incidência da doença em mulheres. Esta técnica é promissora para estudar as vias metabólicas, investigar substâncias marcadas mais adequadas para tornar mais rápida a detecçäo radiométrica do fungo e para acompanhar os efeitos de outras drogas e fatores sobre o metabolismo do P.brasiliensis "in vitro" (