Evidence of anti-Hcp100 antibodies in COVID-19 critically ill patients with detectable anti-histoplasmin antibodies in a highly endemic area for histoplasmosis.

Patients with severe COVID-19 are at increased risk for invasive fungal infections, which are underestimated. Histoplasmosis reactivation in endemic areas should not be overlooked in this population. In a previous study, seroconversion to anti-histoplasmin antibodies by ELISA was detected in 6/39 (15.4%) patients with severe COVID-19. In this work, samples were further investigated to detect seroconversion to antibodies against the Histoplasma capsulatum 100-kDa antigen (Hcp100) by ELISA. Seroconversion to anti-Hcp100 antibodies was detected in 7/39 patients, of whom 6 also seroconverted anti-histoplasmin antibodies. These results reinforce previous findings that show histoplasmosis as an underdiagnosed fungal entity complicating COVID-19.

This study verifies that patients with severe COVID-19 at intensive care units are at risk for histoplasmosis reactivation in endemic areas. Accurate diagnosis of this deadly fungal disease among critically ill patients with COVID-19 living in endemic areas for histoplasmosis is needed.

Quantitative determination of voriconazole by thionine reduction and its potential application in a pharmaceutical and clinical setting.

Voriconazole (VCZ) is a triazolic drug used to treat serious fungal infections and invasive mycosis and has also been more recently used as a generic antifungal treatment. However, VCZ therapies can cause undesirable side effects and doses must be carefully monitored before administration to avoid or reduce severe toxic effects. Analytical techniques used to quantify VCZ are mostly based on HPLC/UV and often associated with multiple technical steps as well as expensive equipment. The present work aimed to develop an accessible and affordable spectrophotometric technique in the visible range (λ = 514 nm) for the simple quantification of VCZ. The technique was based on VCZ-induced reduction of thionine (TH, red) to leucothionine (LTH, colorless) under alkaline conditions. The reaction showed a linear correlation over the range of 1.00 µg mL-1 to 60.00 µg mL-1 at room temperature, the limits of detection and quantification being 1.93 µg mL-1 and 6.45 µg mL-1, respectively. VCZ degradation products (DPs) according to 1H and 13C-NMR spectrometric determinations not only showed good agreement with the ones previously reported (DP1 and DP2 - T. M. Barbosa, G. A. Morris, M. Nilsson, R. Rittner and C. F. Tormena, RSC Adv., 2017, DOI: 10.1039/c7ra03822d), but also revealed a new degradation product (DP3). Mass spectrometry not only confirmed the presence of LTH as a result of the VCZ DP-induced TH reduction, but also revealed the formation of a novel and stable Schiff base as a reaction product between DP1 and LTH. The latter finding became significant as it stabilizes the reaction for quantification purposes, by hindering LTH ↔TH redox reversibility. This analytical method was then validated according to the ICH Q2 (R1) guidelines, and additionally, it could be demonstrated as applicable for the reliable VCZ quantification in commercially available tablets. Importantly, it also represents a useful tool for detecting toxic threshold concentrations in human plasma from VCZ-treated patients, alerting when these risky limits are exceeded. In this way, this technique independent from sophisticated equipment, highly qualifies as a low-cost, reproducible, trustable, and non-laborious alternative method for VCZ measurements from different matrices.

Evaluación de virus papiloma humano de alto y bajo riesgo oncogénico en la cavidad bucal de pacientes VIH positivos / Evaluation of human papillomavirus of high and low oncogenic risk in the oral cavity of HIV positive patients

Objetivo. Realizar la detección y tipificación de virus papiloma humano (VPH) en la cavidad bucal de un grupo de pacientes VIH positivos, atendidos en el Centro de Atención de Pacientes con Enfermedades Infectocontagiosas (CAPEI) de la Facultad de Odontología-Universidad Central de Venezuela. Métodos. Se evaluaron 31 hisopados bucales de pacientes VIH positivos para la infección por VPH, mediante el Sistema de Hibridación Reversa de INNO-LiPA que detecta 28 genotipos de VPH de alto y bajo riesgo oncogénico. Resultados. El 61,0% de las muestras evaluadas presentó infección por VPH. El genotipo 6 fue el más frecuente (73,68%), seguido de los genotipos 18, 11 y 16 con 63,16%, 37,0% y 32,0% respectivamente. El 74,0% de las muestras positivas para VPH presentaron infecciones múltiples, siendo más frecuente la coinfección mixta (35,70%) con los genotipos de VPH-6/18 de bajo y alto riesgo oncogénico, 21,40% con los genotipos 6/11/18 y 6/11, cada una. Seguido de 14,30% de las muestras que presentaron infección con VPH-6/11/16/18 y 7,10% con los genotipos 11/16 de bajo y alto riesgo oncogénico. Conclusiones. La alta frecuencia de infección con VPH de alto riesgo oncogénico y la presencia de múltiples genotipos observada en la cavidad bucal de individuos VIH positivos, que no presentaron lesiones compatibles con esta infección en el examen extra e intrabucal, indica que los métodos moleculares de diagnóstico son importantes en la detección de infecciones subclínicas y latentes, lo que puede permitir un mejor seguimiento y manejo más oportuno de estos pacientes con mayor riesgo de desarrollar neoplasias malignas en la cavidad bucal.

Objective. Perform human papilomavirus (HPV) detection and typing in the oral cavity in a group of HIV positive patients, treated at the Center for Care of Patients with Infectious Diseases (CAPEI) of the Faculty of Dentistry-Central University of Venezuela. Methods. Thirty-one oral swabs from HIV-positive patients were evaluated to detect HPV infection using the INNO-LiPA Reverse Hybridization System that detects 28 HPV genotypes of high and low oncogenic risk. Results. The 61.0% of the evaluated samples had an HPV infection. The low risk genotype 6 was the most frequent (73.68%), followed by genotypes 18, 11 and 16 with 63.16%, 37.0%, and 32.0%, respectively. Seventy-four percent of HPV positive samples had multiple infections, being the more frequent the mixed coinfection (35.70%), with HPV genotypes 6/18 of low and high oncogenic risk, 21.40% with genotypes 11/6/18 and 6/11, each one, followed by 14.30% of the samples presented infection with HPV-6/11/16/18 and 7.10% with the 11/16 genotypes of low and high oncogenic risk. Conclusions. The high frequency of infection with high oncogenic risk HPV types and the presence of multiple genotypes observed in the oral cavity of HIV positive patients, who did not present lesions compatible with this infection in the extra and intraoral examination, indicates that molecular diagnostic methods are important in the detection of subclinical and latent infections, which may allow better follow-up and more timely management of these patients with a higher risk of developing malignant lesions in the oral cavity