Revista Do Instituto De Medicina Tropical De Sao Paulo最新文献

To assess SARS-CoV-2 reinfection incidence in the post-vaccination period, we carried out a prospective cohort study of blood donors from Amazonas and Sao Paulo States, Brazil. Anti-nucleocapsid immunoglobulin (IgG anti-N) tests carried out by blood centers in 2020 were used to identify previous SARS-CoV-2 infections in blood donors and divide them into two groups: prior infection (n=386) and no prior infection (n=111). From March 2021 to January 2022, donors were followed up for six months, during which IgG anti-N and real-time reverse transcription polymerase chain reaction tests were performed every two months to detect SARS-CoV-2 infections. Symptoms and vaccination status were also recorded. Most participants (93.6%) received at least one COVID-19 vaccine dose. Reinfection incidence in the prior infection group equaled 1.39 per 100 person-months (95% CI: 0.90-2.06), in comparison to 2.68 per 100 person-months (95% CI: 1.28-4.93) for new infections in those without prior infection. The incidence risk ratio showed no significant association (0.52, 95% CI: 0.25-1.13). However, prior infection significantly increased the probability of remaining uninfected (Log-rank: p=0.009). Most reinfections (84%) showed no symptoms and occurred post-vaccination during the Delta and Omicron waves. IgG anti-N seroprevalence decreased in the prior infection group (from 35.5% at baseline to 22.5% after six months, p=0.003). Despite no significant incidence risk ratio differences, donors with prior infection had lower infection rates and a higher likelihood of remaining uninfected. Persistent post-vaccination asymptomatic infections emphasize the need for ongoing prevention, genomic surveillance, and booster programs to address emerging variants and protect vulnerable populations.

Mycobacterium marinum is a nontuberculous mycobacterium and an opportunistic pathogen which infects humans. Here, we report a case of an 87-year-old female who had extensive verrucous skin lesions on her upper limbs for 18 months. The patient was diagnosed with Mycobacterium marinum infection by pathology and quantitative polymerase chain reaction (qPCR) assay of skin tissue. After five months of oral rifampicin and clarithromycin, the skin lesions regressed completely.

Sporotrichosis, a neglected zoonotic fungal infection, is becoming increasingly prevalent in Brazil, with cats being the primary source of human transmission. This report details the first documented case of zoonotic human sporotrichosis in Mato Grosso State, a non-endemic area; the infection was acquired from an animal in an endemic area. The patient developed a subcutaneous ulcerative lesion following contact with a cat from Minas Gerais State, a known disease hotspot. Initially misdiagnosed, the infection was later confirmed as Sporothrix brasiliensis after fungal culture and molecular analysis. The patient was successfully treated with itraconazole. This case highlights the importance of considering sporotrichosis in the differential diagnosis, even in non-endemic areas, due to the risk of zoonotic transmission. It also emphasizes the need for a One Health approach to improve surveillance, diagnostic accuracy, and management of emerging fungal diseases in endemic and expanding areas.

The recent Oropouche fever outbreak in Sergipe State, Northeastern Brazil, represents a significant expansion of the disease beyond the Amazon. This shift in transmission patterns highlights the urgent need to adapt public health strategies and strengthen surveillance efforts to better understand and manage the spread of the Oropouche virus across diverse ecological and climatic settings.

Early infant immunity to SARS-CoV-2 depends on maternofetal transfer of antibodies. We aimed to analyze the factors modulating the maternofetal transfer of anti-SARS-CoV-2 IgG antibodies following gestational infection during the pandemic in Brazil (April-August 2021). We conducted a retrospective and prospective cohort study involving 509 mother-child dyads tested simultaneously for IgG anti-nucleocapsid antibodies during universal neonatal screening. There were 341 seronegative dyads and 168 seropositive ones. Seropositive neonates were retested two to three months later. We examined the association of neonatal serological status and IgG concentrations with gestational mRNA vaccination, timing of maternal infection, neonatal conditions, and gender. Gestational SARS-CoV-2 infection predicted neonatal IgG seropositivity (OR=3.97; 95%CI=2.69-5.88). Maternal infection in the first, second, or third trimester was associated with progressively greater seropositivity in neonates (34.4%, 51.6%, and 58.2%, respectively; p=0.03). Among seropositive neonates, IgG concentration was higher when mothers reported they had COVID-19 during pregnancy (p=0.04) and tended to be lower in girls (p=0.06). More than half of the seropositive neonates remained seropositive two to three months later (54.1%), which was associated with both maternal and neonatal IgG concentration at birth (p<0.001). Higher neonatal IgG concentrations at birth were associated with the persistence of anti-N IgG antibodies for two to three months in more than half of the seropositive newborns. This study provides an additional understanding of the dynamics of maternofetal antibody transfer.

Most SARS-CoV-2 infections are asymptomatic or cause only mild illness, but severe respiratory disease can develop, sometimes requiring oxygen support. Immunopathological damage resulting from an abnormal inflammatory response in patients with severe disease is known to be the main determinant of disease outcome. Studies show that anti-inflammatory therapies work best when used before widespread immunopathological damage has occurred. Similarly, it was thought that intravenous immunoglobulin (IVIG)-holding multiple immunomodulatory effects-would provide clinically favorable results, but recent studies suggest otherwise. Still, the literature shows few studies evaluating the efficacy of IVIG according to the time of administration and there are no studies comparing it with established treatments, such as tocilizumab. In this study, we aimed to evaluate the effects of early administration of tocilizumab and IVIG on clinical outcome in patients with severe COVID-19. Patients with progressive clinical and laboratory deterioration who received tocilizumab or IVIG between 07/2020 and 10/2020 in a public hospital ward were retrospectively evaluated. A total of 74 patients were identified, of whom 29 (39%) received IVIG only and 26 (35%) received tocilizumab only. As a result, patients with severe COVID-19 who received IVIG in early stages of the disease did not have better clinical outcomes regarding mortality, length of hospital stay and ICU admission compared to those who received tocilizumab. Moreover, there is no data to support the use of IVIG in COVID-19 patients with severe disease, as it is associated with more severe side effects and is more expensive than tocilizumab.

Coinfection with leptospirosis and other infectious agents pose major challenges in medical practice, often due to difficulties in isolating these agents, symptoms overlap, and lack of specific investigation protocols in areas with emerging and re-emerging diseases. Consequently, knowledge regarding these coinfections and their impact on clinical outcomes are limited. A previously healthy 33-year-old woman, with no history of chronic or malignance diseases, was admitted with febrile icteric illness, pulmonary hemorrhage, acute kidney injury, thrombocytopenia, and shock. Leptospirosis, COVID-19, human rhinovirus, and dengue in the acute phase were clinically and pathologically diagnosed. Multiple coinfections can rapidly lead to multiple organ and system failure, often resulting in a fatal outcome.

Psoas muscle abscess is an insidious disease, with varied clinical manifestations and a challenging diagnosis. This pathology has been more frequently identified due to the increased availability of high-quality radiological imaging, such as computed tomography. In Brazil, Mycobacterium tuberculosis is the most common secondary etiologic agent of psoas abscess. We report the case of a 28-year-old immunocompetent man diagnosed with disseminated tuberculosis, affecting the lungs, lumbar spine, and psoas muscle, leading to permanent locomotion sequelae. This case is very relevant for osteoarticular complaints, as low back pain and limping were the initial symptoms. Diagnosis was confirmed by ultrasound-guided percutaneous drainage of the psoas muscle abscess and detection of the M. tuberculosis complex via Xpert MTB/RIF. A 12-month treatment with antitubercular drugs was effective.

[This corrects the article doi: 10.1590/S1678-9946202466024].