Background: Recent studies have suggested that the gut microbiota is altered in children with juvenile idiopathic arthritis (JIA). However, age, sex, and body mass index (BMI) were not matched in the previous studies, and the results are inconsistent. We conducted an age-, sex-, and BMI-matched cross-sectional study to characterize the gut microbiota in children with JIA, and evaluate its potential in clinical prediction. Methods: A total of 40 patients with JIA and 42 healthy controls, ranging from 1 to 16 years, were enrolled in this study. Fecal samples were collected for 16S rDNA sequencing. The data were analyzed using QIIME software and R packages. Specifically, the random forest model was used to identify biomarkers, and the receiver operating characteristic curve and the decision curve analysis were used to evaluate model performance. Results: A total of 39 fecal samples from patients with JIA, and 42 fecal samples from healthy controls were sequenced successfully. The Chao 1 and Shannon-Wiener index in the JIA group were significantly lower than those in the control group, and the Bray-Curtis dissimilarity also differed significantly between the two groups. The relative abundance of 4 genera, Anaerostipes, Dialister, Lachnospira, and Roseburia, decreased significantly in the JIA group compared to those in the control group. The 4 genera included microbes that produce short-chain fatty acids (SCFAs) and were negatively correlated with some rheumatic indices. Moreover, 12 genera were identified as potential biomarkers by using the nested cross-validation function of the random forest. A random forest model constructed using these genera was able to differentiate the patients with JIA from the healthy controls, and the area under the receiver operating characteristic curve was 0.7975. The decision curve analysis indicated that the model had usefulness in clinical practice.

BackgroundTakayasu arteritis (TA) is a chronic granulomatous vasculitis with unknown pathophysiology. TA with severe aortic obstruction has a poor prognosis. However, the efficacy of biologics and appropriate timing of surgical intervention remain controversial. We report a case of tuberculosis (TB)-associated TA with aggressive acute heart failure (AHF), pulmonary hypertension (PH), thrombosis, and seizure, who failed to survive after surgery.Case presentationA 10-year-old boy who developed a cough with chest tightness, shortness of breath, hemoptysis with reduced left ventricular ejection fraction, PH, and increased C-reactive protein and erythrocyte sedimentation rate was hospitalized at the pediatric intensive care unit of our hospital. He had strongly positive purified protein derivative skin test and interferon-gamma release assay result. Computed tomography angiography (CTA) showed occlusion of proximal left subclavian artery and stenosis of descending aorta and upper abdominal aorta. His condition did not improve after administration of milrinone, diuretics, antihypertensive agents, and intravenous methylprednisolone pulse followed by oral prednisone. Intravenous tocilizumab was administered for five doses, followed by two doses of infliximab, but his HF worsened, and CTA on day 77 showed complete occlusion of the descending aorta with large thrombus. He had a seizure on day 99 with deterioration of renal function. Balloon angioplasty and catheter-directed thrombolysis were performed on day 127. Unfortunately, the child's heart function continued to deteriorate and died on day 133.ConclusionTB infection may be related to juvenile TA. The biologics, thrombolysis, and surgical intervention failed to achieve the anticipated effect in our case with aggressive AHF due to severe aortic stenosis and thrombosis. More studies are needed to determine the role of biologics and surgery in such dire cases.