Pegivirus Detection in Cerebrospinal Fluid from Patients with Central Nervous System Infections of Unknown Etiology in Brazil by Viral Metagenomics

Metagenomic next-generation sequencing (mNGS) methodology serves as an excellent supplement in cases where diagnosis is challenging to establish through conventional laboratory tests, and its usage is increasingly prevalent. Examining the causes of infectious diseases in the central nervous system (CNS) is vital for understanding their spread, managing outbreaks, and effective patient care. In a study conducted in the state of São Paulo, Brazil, cerebrospinal fluid (CSF) samples from 500 patients with CNS diseases of indeterminate etiology, collected between 2017 and 2021, were analyzed. Employing a mNGS approach, we obtained the complete coding sequence of Pegivirus hominis (HPgV) genotype 2 in a sample from a patient with encephalitis (named IAL-425/BRA/SP/2019); no other pathogen was detected. Subsequently, to determine the extent of this virus's presence, both polymerase chain reaction (PCR) and/or real-time PCR assays were utilized on the entire collection. The presence of the virus was identified in 4.0% of the samples analyzed. This research constitutes the first report of HPgV detection in CSF samples in South America. Analysis of the IAL-425 genome (9107 nt) revealed a 90% nucleotide identity with HPgV strains from various countries. Evolutionary analyses suggest that HPgV is both endemic and extensively distributed. The direct involvement of HPgV in CNS infections in these patients remains uncertain.

[Endocarditis due to Coxiella burnetii (Q fever): a rare or underdiagnosed disease? Case report]

Q fever is a zoonosis of worldwide distribution that is caused by Coxiella burnetii. However, reports of this disease in Brazil are rare. Seroepidemiological studies have shown relatively high frequencies of antibodies against Coxiella burnetii in populations with occupational exposure. In humans, it can be manifested clinically as acute or chronic disease. Endocarditis is the most frequent chronic form of Q fever and the form with the greatest morbidity and mortality. We report a severe case of endocarditis due to Coxiella burnetii acquired in Brazil that had a fatal outcome, despite specific antibiotic therapy and valve surgery treatment.

Infective Endocarditis due to Bartonella spp. and Coxiella burnetii: Experience at a Cardiology Hospital in Sao Paulo, Brazil

Bartonella spp. and Coxiella burnetii are recognized as causative agents of blood culture-negative endocarditis (BCNE) in humans and there are no studies of their occurrences in Brazil. The purpose of this study is to investigate Bartonella spp. and C. burnetii as a causative agent of culture-negative endocarditis patients at a cardiology hospital in São Paulo, Brazil. From January 2004 to December 2004 patients with a diagnosis of endocarditis at our Institute were identified and recorded prospectively. They were considered to have possible or definite endocarditis according to the modified Duke criteria. Those with blood culture-negative were tested serologically using the indirect immunofluorescent assay (IFA) for Bartonella henselae, B. quintana, and C. burnetii. IFA-IgG titers >800 for Bartonella spp. and C. burnetii were considered positive. A total of 61 patients with endocarditis diagnosis were evaluated, 17 (27%) were culture-negative. Two have had IgG titer greater than 800 (>/=3,200) against Bartonella spp. and one against C. burnetii (phase I and II>/=6,400). Those with Bartonella-induced endocarditis had a fatal disease. Necropsy showed calcifications and extensive destruction of the valve tissue, which is diffusely infiltrated with mononuclear inflammatory cells predominantly by foamy macrophages. The patient with C. burnetii endocarditis received specific antibiotic therapy. Reports of infective endocartitis due to Bartonella spp. and C. burnetii in Brazil reveal the importance of investigating the infectious agents in culture-negative endocarditis.