RESUMO
Phenotypic manifestations of infectious diseases are closely related to individual immune responses. Methods to extract information from patients' own immune reactions would be of great use for both diagnosis and treatment. Dengue fever is one of the diseases that clinical aggravations could occur paradoxically after humoral immunity appears. This property makes dengue fever an excellent disease model to explore. A principal component analyses (PCAs)-based framework derived from a prior vaccination study was developed. The framework was verified by successful demonstrations of known IgG signatures from a Mexico Dengue data set. Afterward the pipeline was tested upon de novo IgG and IgA libraries of Dengue patients from southern Taiwan. We discovered four infection signatures within IgG repertoires, two of which were identical to previous reports. However, it was IgA but not IgG that could differentiate hemorrhagic from non-hemorrhagic patients. IgA repertoires were found more diversified among bleeders, from whom seven signature clusters were characterized. The expressions of transforming growth factor beta 1 (TGFß1) and accordingly mediated class-switch activity of IgA were distinct only among the PCA-segregated bleeding group. In sum, intercontinental sharing of IgG signatures in dengue fever was demonstrated via a unified working flow. Differential regulation of IgA class-switch with associated diversity expansion plus existences of hemorrhage-restricted clusters were shown. The ability of the framework to find common IgG signatures would implicate applications to infections even from unknown pathogens. The clusters within IgA repertoires could offer perspectives to other IgA-related bleeding disorders such as Henoch-Schönlein purpura or IgA nephropathy. Substantiated grounds for IgA-specific effector function via TGFß1-mediated class-switch would be a new factor to consider for infectious diseases.
RESUMO
BACKGROUND: The gastroesophageal reflux disease (GERD) questionnaire (GerdQ) is a validated questionnaire that was developed recently to help identify GERD patients. The sensitivity and specificity of GerdQ for the diagnosis of GERD in adult patients were 65% and 71%, respectively. Because the application of GerdQ in pediatric population is largely unknown, the aim of this study is to establish the endoscopic correlation between Chinese GerdQ and grades of erosive esophagitis (EE) in Taiwanese children. METHODS: Seventy-four children (aged 9-18 years) were evaluated by our version of the Chinese GerdQ prior to receiving esophagogastroduodenoscopy for warning upper gastrointestinal symptoms. Grades of EE were assessed blindly, according to the Los Angeles classification. The sensitivity and specificity of GerdQ for detecting endoscopic EE were analyzed. RESULTS: In 74 patients, the male to female ratio was 1:1.1 and the mean age was 14.2 ± 2.3 years (age range: 9.2-17.9 years). Thirty-nine percent of the enrolled patients had EE. The sensitivity and specificity of GerdQ (with a cutoff score of ≥7) to identify EE patients were 65.5% and 80%, respectively. The odds ratio of GerdQ for a cutoff score of 7 to identify EE was 7.6 (95% confidence interval = 2.6-21.9, p < 0.001). CONCLUSION: For the identification of EE in children, the Chinese GerdQ had similar sensitivity and specificity to that used for adults. This questionnaire may be applied as a noninvasive screening tool.