Mariângela Ribeiro Resende

In countries where Dengue virus is endemic, the occurrence of outbreaks and epidemic events is strongly associated with viral genomic evolution. In addition, the introduction of a new agent, such as Zika virus, in a naive population and its concomitant circulation may increase mutations and virulence. This study aimed to characterize the molecular patterns and circulation of Zika and Dengue viruses inland of midwestern Brazil. Samples from reported cases of zika and dengue fever were subjected to molecular and phylogenetic analyses. Partial genomes of these viruses were recovered and characterized from six samples. Phylogenetic analysis revealed that the Zika virus clustered within the American strain of Asian/American lineage and Dengue virus grouped within the Brazilian lineage (BR04) of serotype 2 from the Asian/American genotype. Amino acid substitutions, and consequently nonsynonymous mutations, were identified in the RdRp domain of the NS5 protein coding region in the recovered genomes from both viruses. These findings highlight the importance of molecular epidemiological surveillance, especially in endemic regions with cocirculation and substantial epidemic risk. Ongoing monitoring efforts are crucial to better understand viral evolution and its potential impact on future outbreaks and epidemic dynamics.

Spinal infections caused by Mycobacterium abscessus are rare and difficult to treat. We report the first case of M. abscessus subsp. massiliense spondylodiscitis temporally associated with spinal anesthesia. A 57-year-old man developed back pain after undergoing spinal anesthesia for prostate surgery. Six months later, decompressive laminectomy was performed; results for bacterial and fungal culture and molecular testing for Mycobacterium tuberculosis were negative. Two years later, a mycobacterial culture of material from a paravertebral abscess revealed the presence of M. abscessus, later identified as subsp. massiliense. Treatment with imipenem, amikacin, tigecycline, clofazimine, and clarithromycin resulted in clinical and radiological improvement. This report highlights the diagnostic and therapeutic challenges of this case.

Introduction: Since 2018, WHO has endorsed the use of whole-genome sequencing (WGS) of Mycobacterium tuberculosis complex isolates to detect drug-resistant tuberculosis (DR-TB). This endorsement was based on the assumption that a faster and more detailed description of the resistance profile would improve treatment prescription for DR-TB by healthcare providers, and hence the treatment outcomes of patients. Nonetheless, this assumption has not been tested in routine clinical practice and different scenarios. In Brazil, WGS is not routinely used for the diagnosis of DR-TB, having been carried out in only a few centres for research purposes. With this trial, we will evaluate whether a WGS-based drug-resistance report improves treatment adequacy in patients with pulmonary DR-TB, compared with the current standard-of-care diagnostic methods used in the state of São Paulo, Brazil. Methods and analysis: We will conduct a non-randomised controlled clinical trial with two arms to compare the intervention group (ie, individuals receiving a WGS-based report) with a historical control group (i.e., individuals who received resistance diagnostics based on the standard of care of conventional genotyping and phenotyping techniques). The primary outcome will be the proportion of patients whose treatment scheme was adequate based on complete resistance profile determined by WGS and/or phenotypic drug-susceptibility testing (pDST). Other secondary outcomes will also be considered. The target sample size is 88 eligible patients per group. The intervention group will be prospectively recruited over 18 months and the control group will be composed of patients diagnosed with pulmonary DR-TB up to 2 years before the start of the trial. To ensure comparability, isolates from the control group will undergo WGS retrospectively, and pDST will be performed retrospectively in both groups. This clinical trial will take place in six medical centres for the treatment of DR-TB in the state of São Paulo. This study is intended to support the implementation of the WGS in the routine diagnosis of DR-TB in the state of São Paulo. Ethics and dissemination: Ethical approval was obtained from the Human Research Committee of the Institute of Biomedical Sciences, University of São Paulo, Brazil (CAAE: 79497924.1.1001.5467). Study results will be published in peer-reviewed journals and disseminated to policymakers and stakeholders. Trial registration number: U1111-1308-4669.

Arboviruses represent a public health problem in developing countries. Accurate diagnosis has been challenging in Dengue virus endemic countries, especially since the introduction of the Zika and Chikungunya viruses. The aim of this study was to determine the sensitivity and specificity of nested Reverse Transcription Polymerase Chain Reaction (nested-RT-PCR) in a Zika virus epidemic setting. A total of 179 serum samples from patients with acute febrile syndrome reported between 2015 and 2016 were analyzed by nested-RT-PCR using real-time PCR (RT-qPCR) as reference test. The nested-RT-PCR assay demonstrated moderate agreement (kappa = 0.49) in identifying Dengue virus, resulting in 40.00% positive and 99.42% negative predictive values. Zika virus detection showed fair agreement (kappa = 0.29), with 100% positive and 92.61% negative predictive values (p-value < 0.05, Fisher’s exact test). The diagnostic accuracy rates for the nested-RT-PCR assays were 97.76% for Dengue virus and 92.74% for Zika virus. The sensitivity and specificity of nested-RT‒PCR for detecting Dengue virus were 66.66% and 98.29%, respectively; Zika virus RNA detection had 18.75% sensitivity and 100% specificity with the nested-RT-PCR protocol. In conclusion, the RT-qPCR assay is the most reliable method for diagnosing suspected cases of dengue and zika fever, providing adequate, timely and accurate laboratory responses to the proper management of patients, despite the high overall analytical accuracy of nested-RT-PCR.

Streptococcus constellatus, a member of the Streptococcus anginosus group, is a commensal bacterium that causes pyogenic infections, particularly abscesses. This report describes the case of a 28-year-old immunocompetent man who developed a brain abscess and epidural empyema after pneumonia. MRI suggested an abscess, which was confirmed by culture, revealing S. constellatus. Treatment included abscess drainage and ceftriaxone administration, which led to a full recovery. Diagnosis is challenging because of overlapping features with other bacteria. Imaging and culturing are crucial for identification. This case highlights the importance of considering S. constellatus in central nervous system infections, even in immunocompetent individuals.

Justificativa e Objetivos: Arboviroses impactam a saúde pública mundialmente, causando graves prejuízos à saúde humana. Os arbovírus causam síndromes febris agudas semelhantes, desafiando o diagnóstico diferencial e a notificação adequada. O objetivo desta pesquisa foi descrever o perfil epidemiológico e laboratorial dos casos suspeitos de arboviroses notificados no sudeste de Mato Grosso (MT) durante a primeira emergência brasileira do Zika vírus. Métodos: as características clínicas e epidemiológicas das arboviroses foram analisadas de forma retrospectiva e descritiva. Amostras de soro foram avaliadas por reação em cadeia da polimerase em tempo real via transcriptase reversa para detecção de Zika, Dengue e Chikungunya, e por imunoensaio para detecção de IgM e IgG contra Zika. Resultados:Dos 197 pacientes, 63% eram do sexo feminino e oito estavam grávidas. A média de idade foi de 32 anos, dos quais 44% tinham 19 e 59 anos; 28% eram brancos; 34% eram alfabetizados; e 58,9% eram residentes urbanos. Cerca de 61% dos casos ocorreram durante os períodos chuvosos, sendo 12,1% em três regiões da área de estudo. Os distúrbios musculoesqueléticos foram as principais queixas (22,8%), seguidos de febre (13,7%), exantema e petéquias (12,6%), cefaleia (11,7%), prurido (10%), manifestações oftalmológicas (6,1%) e manifestações gastrointestinais (5,6%). Por meio de ensaios moleculares, foram detectados 8,9% e 1,7% de Zika e Dengue, respectivamente, nas amostras testadas. Os ensaios sorológicos para Zika mostraram 10,6% de amostras positivas para IgM e 55,8% para IgG. Conclusão: Este estudo fornece o perfil clínico, epidemiológico e laboratorial da emergência do Zika vírus em ambientes de alta endemicidade de dengue. A relevância do estudo é compreender a introdução e ocorrência concomitante de uma nova arbovirose.

We present a patient referred for investigation of adrenal insufficiency, confirmed due to disseminated paracoccidioidomycosis (PCM), with abdominal and central nervous system (CNS) involvement. Establishing the pathogenesis and immunological processes involved in chronic or latent infections by PCM has been challenging. Medical doctors caring for patients with immunodeficiencies should learn about these fungal infections to properly guide travel planning and have this possibility in the diagnostic arsenal when the patient returns from endemic areas. After 13 months of treatment, the patient showed good clinical evolution, and we repeated imaging exams, showing partial improvement of the preview lesions. Diagnosis and treatment can prevent catastrophic events.