Background Steroid use for COVID-19 is based on the possible role of these drugs in mitigating the inflammatory response, mainly in the lungs, triggered by SARS-CoV-2. This study aimed at evaluating at evaluating the efficacy of methylprednisolone (MP) among hospitalized patients with suspected COVID-19. Methods Parallel, double-blind, placebo-controlled, randomized, phase IIb clinical trial was performed with hospitalized patients aged ≥ 18 years with clinical, epidemiological and/or radiological suspected COVID-19, at a tertiary care facility in Manaus, Brazil. Patients were randomly allocated (1:1 ratio) to receive either intravenous MP (0.5 mg/kg) or placebo (saline solution), twice daily, for 5 days. A modified intention-to-treat (mITT) analysis was conducted. The primary outcome was 28-day mortality. ClinicalTrials Identifier NCT04343729. Findings From April 18 to June 16, 2020, 647 patients were screened, 416 randomized, and 393 analyzed as mITT, MP in 194 and placebo in 199 individuals. SARS-CoV-2 infection was confirmed by RT-PCR in 81.3%. Mortality at day 28 was not different between groups. A subgroup analysis showed that patients over 60 years in the MP group had a lower mortality rate at day 28. Patients in the MP arm tended to need more insulin therapy, and no difference was seen in virus clearance in respiratory secretion until day 7. Conclusion The findings of this study suggest that a short course of MP in hospitalized patients with COVID-19 did not reduce mortality in the overall population.

Background The presence of Plasmodium vivax malaria parasites in the human bone marrow (BM) is still controversial. However, recent data from a clinical case and experimental infections in splenectomized nonhuman primates unequivocally demonstrated the presence of parasites in this tissue. Methods In the current study, we analyzed BM aspirates of 7 patients during the acute attack and 42 days after drug treatment. RNA extracted from CD71+ cell suspensions was used for sequencing and transcriptomic analysis. Results We demonstrated the presence of parasites in all patients during acute infections. To provide further insights, we purified CD71+ BM cells and demonstrated dyserythropoiesis and inefficient erythropoiesis in all patients. In addition, RNA sequencing from 3 patients showed that genes related to erythroid maturation were down-regulated during acute infections, whereas immune response genes were up-regulated. Conclusions This study thus shows that during P. vivax infections, parasites are always present in the BM and that such infections induced dyserythropoiesis and ineffective erythropoiesis. Moreover, infections induce transcriptional changes associated with such altered erythropoietic response, thus highlighting the importance of this hidden niche during natural infections.

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Despite the availability of effective antimicrobials, tuberculosis (TB) is still a serious health threat. Mortality is even higher in people living with HIV who are diagnosed with TB. New therapies are needed to shorten the time required to cure TB and decrease fatality rates in this population. N-acetylcysteine (NAC) is a glutathione precursor and has shown recently in experimental setting to present in vitro and in vivo anti-mycobacterial activity. We test the hypothesis that NAC is safe, well tolerated and secondarily efficacious as adjunctive anti-TB therapy in hospitalized individuals with HIV-associated TB. Patients were enrolled sequentially in a tertiary care center, in the Brazilian Amazon. We performed a randomized, parallel group, single-center, open study trial of two arms, in hospitalized patients over 18 years of age, with microbiologically confirmed pulmonary TB in HIV: one with rifampicin, isoniazid, pyrazinamide and ethambutol at standard doses (Control Group), and a second in which NAC 600 mg bid for eight weeks was added (NAC Group). A total of 21 and 18 patients were enrolled to the Control Group and NAC Group, respectively. Adverse event rates were similar in the two arms. Our findings suggest that in the more critical population of hospitalized patients with HIV-associated TB, the use of NAC was not unsafe, despite the low

Tuberculosis (TB) still causes significant morbidity and mortality worldwide, especially in persons living with human immunodeficiency virus (HIV). This disease is hallmarked by persistent oxidative stress and systemic inflammation. N-acetylcysteine (NAC), a glutathione (GSH) precursor, has been shown in experimental models to limit Mycobacterium tuberculosis infection and disease both by suppression of the host oxidative response and through direct antimicrobial activity. In a recent phase II randomized clinical trial (RIPENACTB study), use of NAC as adjunct therapy during the first two months of anti-TB treatment was safe. Whether adjunct NAC therapy of patients with TB-HIV coinfection in the context of anti-TB treatment could directly affect pro-oxidation and systemic inflammation has not been yet formally demonstrated. To test this hypothesis, we leveraged existing data and biospecimens from the RIPENACTB trial to measure a number of surrogate markers of oxidative stress and of immune activation in peripheral blood of the participants at pre-treatment and at the day 60 of anti-TB treatment. Upon initiation of therapy, we found that the group of patients undertaking NAC exhibited significant increase in GSH levels and in total antioxidant status while displaying substantial reduction in lipid peroxidation compared to the control group. Only small changes in plasma concentrations of cytokines were noted. Pharmacological improvement of the host antioxidant status appears to be a reasonable strategy to reduce TB-associated immunopathology.

Snakebites were included by the World Health Organization in their list of neglected diseases. In Latin America, most snakebites are caused by species of the Viperidae family, notably by the genus Bothrops. Bothrops atrox accounts for 90% of the cases of envenoming in the Brazilian Amazon. In this report, we present a series of three cases of snakebites that evolved with hemorrhagic stroke due to delays in the access to antivenom in the Brazilian Amazon, being fundamental for diagnosis to validate the clinical suspicion and make decisions that would improve the treatment and prognosis of the patients.

Background: The detection of Mycobacterium tuberculosis (MTB) in the intensive care unit (ICU) presents several challenges, mainly associated to the clinical state of the patient. The presence of HIV infection further aggravates this scenario, requiring a reliable collection method, with better performance in the microbiological/molecular techniques to be used. We evaluated the performance of two methods for sample collection, mini bronchoalveolar lavage (Mini-BAL) and endotracheal aspirate (ETA), for diagnosis of pulmonary tuberculosis (PTB) in critically ill patients.Methods: This prospective study involved 26 HIV positive ICU internalized patients, with presumptive PTB who required mechanical ventilation. Two samples were obtained prospectively from 26 HIV ICU patients with presumptive PTB by Mini-BAL and ETA. The samples were processed for smear microscopy, Löwenstein-Jensen medium and the BACTEC Mycobacteria Growth Indicator Tube 960 system®. We define as confirmed PTB patients with positive MTB culture. Furthermore, all samples obtained through the Mini-BAL were analyzed by Xpert® MTB/RIF. Results: Our results demonstrated that the respiratory samples obtained by Mini-BAL were able to increase MTB detection in critically ill patients with presumptive PTB. The Mini-BAL allowed 30% increased recovery and guaranteed enough sample volume for processing in all methods. In addition, the larger volume of the samples obtained with this technique enabled the Xpert® MTB/RIF molecular test for diagnosis of TB. Conclusions:The Mini-BAL showed be an acceptable alternative to ETA in this population, since these critically ill and often-immunocompromised patients are more likely to develop complications related to invasive procedures.

Gas-forming pyogenic liver abscess (GPLA) is an uncommon and potentially fatal disease that represents 7-24% of pyogenic liver abscess cases. Diabetes mellitus is a wellknown risk factor, and the main etiological agent is Klebsiella pneumoniae. Escherichia coli is also associated with gas formation, particularly in the presence of biliary disorders. In South America, parasitic diseases have been described as predisposing factors for pyogenic liver abscesses and should be considered during etiological investigation. Clinical symptoms include fever and abdominal pain, but the presentation can be non-specifi c. Diagnosis is facilitated by abdominal ultrasound and computed tomography scanning ( Figure A); the presence of air is observed in less than 36% of chest roentgenograms, simulating pneumoperitoneum ( Figure B). The fatality rate due to gas-forming abscesses is higher than that due to non-