Understanding yellow fever-associated myocardial injury: an autopsy study

BACKGROUND

Yellow fever (YF) is a viral hemorrhagic fever, endemic in parts of South America and Africa. There is scarce evidence about the pathogenesis of the myocardial injury. The objective of this study is to evaluate the cardiac pathology in fatal cases of YF.

METHODS

This retrospective autopsy study included cases from the São Paulo (Brazil) epidemic of 2017-2019. We reviewed medical records and performed cardiac tissue histopathological evaluation, electron microscopy, immunohistochemical assays, RT-qPCR for YF virus (YFV)-RNA, and proteomics analysis on inflammatory and endothelial biomarkers.

FINDINGS

Seventy-three confirmed YF cases with a median age of 48 (34-60) years were included. We observed myocardial fibrosis in 68 (93.2%) patients; cardiomyocyte hypertrophy in 68 (93.2%); endothelial alterations in 67 (91.8%); fiber necrosis in 50 (68.5%); viral myocarditis in 9 (12.3%); and secondary myocarditis in 5 (6.8%). Four out of five patients with 17DD vaccine-associated viscerotropic disease presented with myocarditis. The cardiac conduction system showed edema, hemorrhages and endothelial fibrinoid necrosis. Immunohistochemistry detected CD68-positive inflammatory interstitial cells and YFV antigens in endothelial and inflammatory cells. YFV-RNA was detected positive in 95.7% of the cardiac samples. The proteomics analysis demonstrated that YF patients had higher levels of multiple inflammatory and endothelial biomarkers in comparison to cardiovascular controls, and higher levels of interferon gamma-induced protein 10 (IP-10) in comparison to sepsis (p = 0.01) and cardiovascular controls (p < 0.001) in Dunn test.

INTERPRETATION

Myocardial injury is frequent in severe YF, due to multifactorial mechanisms, including direct YFV-mediated damage, endothelial cell injury, and inflammatory response, with a possible prominent role for IP-10.

FUNDING

This study was funded by Fundação de Amparo à Pesquisa do Estado de São Paulo, Bill and Melinda Gates Foundation, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior.

Impact of Three Methods of Ischemic Preconditioning on Ischemia-Reperfusion Injury in a Pig Model of Liver Transplantation

BACKGROUND

Ischemic preconditioning (IPC), either direct (DIPC) or remote (RIPC), is a procedure aimed at reducing the harmful effects of ischemia-reperfusion (I/R) injury.

OBJECTIVES

To assess the local and systemic effects of DIPC, RIPC, and both combined, in the pig liver transplant model.

MATERIALS AND METHODS

Twenty-four pigs underwent orthotopic liver transplantation and were divided into 4 groups: control, direct donor preconditioning, indirect preconditioning at the recipient, and direct donor with indirect recipient preconditioning. The recorded parameters were: donor and recipient weight, graft-to-recipient weight ratio (GRWR), surgery time, warm and cold ischemia time, and intraoperative hemodynamic values. Blood samples were collected before native liver removal (BL) and at 0 h, 1 h, 3 h, 6 h, 12 h, 18 h, and 24 h post-reperfusion for the biochemical tests: aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), creatinine, BUN (blood urea nitrogen), lactate, total and direct bilirubin. Histopathological examination of liver, gut, kidney, and lung fragments were performed, as well as molecular analyses for expression of the apoptosis-related BAX (pro-apoptotic) and Bcl-XL (anti-apoptotic) genes, eNOS (endothelial nitric oxide synthase) gene, and IL-6 gene related to inflammatory ischemia-reperfusion injury, using real-time polymerase chain reaction (RT-PCR).

RESULTS

There were no differences between the groups regarding biochemical and histopathological parameters. We found a reduced ratio between the expression of the BAX gene and Bcl-XL in the livers of animals with IPC versus the control group.

CONCLUSIONS

DIPC, RIPC or a combination of both, produce beneficial effects at the molecular level without biochemical or histological changes.

How a discerning cytological examination can aid in the diagnosis of infectious diseases: case reports

Infections caused by uncommon and resistant pathogens in unusual sites have been increasingly reported in medical literature. We describe four cases of rare cytological findings and clinical impact for patients. In the first case, Aspergillus sp and Pneumocystis jirovecii were observed in the bronchoalveolar lavage of a patient with severe systemic lupus. In the second and third cases, we describe the presence of Trichomonas sp and Strongyloides sp larvae in samples of pleural and peritoneal fluid, respectively. The fourth report is about a patient with a wrist subcutaneous nodule whose synovial aspiration and cytology revealed the presence of brown septate hyphae. The early identification of the infectious agent in the cytological examination was essential for the introduction and/or re-adaptation of therapy in the four cases described. Patients in this report were immunocompromised with severe comorbidities, conditions often associated with unfavorable clinical outcomes.

Detection of sputum cofilin-1 as indicator of malignancy

Cofilin-1 (CFL1), a small protein of 18 kDa, has been studied as a biomarker due to its involvement in tumor cell migration and invasion. Our aim was to evaluate CFL1 as an indicator of malignancy and aggressiveness in sputum samples. CFL1 was analyzed by ELISA immunoassay in the sputum of 73 lung cancer patients, 13 cancer-free patients, and 6 healthy volunteers. Statistical analyses included ANOVA, ROC curves, Spearman correlation, and logistic regression. Sputum CFL1 levels were increased in cancer patients compared to cancer-free patients and volunteers (P<0.05). High expression of sputum CFL1 was correlated to T4 stage (P=0.01) and N stage (P=0.03), tobacco history (P=0.01), and squamous cell carcinoma histologic type (P=0.04). The accuracy of sputum CFL1 in discriminating cancer patients from cancer-free patients and healthy volunteers were 0.78 and 0.69, respectively. CFL1 at a cut-off value of 415.25 pg/mL showed sensitivity/specificity of 0.80/0.70 in differentiating between healthy volunteers and cancer patients. Sputum CFL1 was also able to identify cancer-free patients from patients with lung cancer. The AUC was 0.70 and, at a cut-off point ≥662.63 pg/mL, we obtained 60% sensitivity and 54% specificity. Logistic regression analysis controlled for tobacco history, histologic types, and N stage showed that cancer cell-associated CFL1 was an independent predictor of death. Smoker patients with squamous cell carcinoma, lymph node metastasis and sputum CFL1>1.475 pg/mL showed augmented chance of death, suggesting lung cancer aggressiveness. CFL1 presented diagnostic value in detecting lung cancer and was associated to tumor aggressiveness.

Long and short-term effect of prednisolone in hospitalized infants with acute bronchiolitis

OBJECTIVE

To assess long and short-term effect of prednisolone in hospitalized infants with bronchiolitis.

METHODOLOGY

A randomized and controlled trial was carried out at the Federal University of Rio Grande, Rio Grande-RS, Brazil. Twenty-eight patients were randomly allocated prednisolone (1 mg/kg/day for 5 days) plus standard care, and 24 patients allocated standard care alone. The primary endpoint was the prevalence of post-bronchiolitis wheezing at 1, 3, 6 and 12 months after hospital discharge. The secondary endpoints were: length of hospital stay, duration of oxygen therapy and time to clinical improvement during the hospitalization.

RESULTS

There were no significant differences between the prednisolone and control group in the prevalence of post-bronchioltis wheezing at 1 month (73.1 vs 83.3%, P = 0.5), 3 months (73.1 vs 79.2%, P = 0.7), 6 months (65.4 vs 66.7%, P = 0.9) and 12 months (50.0 vs 58.3%, P = 0.5) after hospital discharge. No reduction was observed in the prednisolone group, compared with the control group, in terms of length of hospital stay (6.0 vs 5.0 days, P = 0.7), duration of oxygen therapy (24.0 vs 24.0 h, P = 0.4) and time to clinical resolution (4.0 vs 4.0 days, P = 0.8).

CONCLUSIONS

Prednisolone has no significant effect on reducing the prevalence of post-bronchiolitis wheezing and on improving the acute course of illness in hospitalized infants with bronchiolitis.

[Intracranial saccular aneurysm: report of 3 cases in a same family]

The authors report the cases of three patients from the same family, all with intracranial saccular aneurysm (left carotid artery, anterior communicating artery, and middle cerebral artery). All three patients were operated on with good recovery and no complications. The authors call attention for some etiopathogenic aspects of familial saccular aneurysms.