Abstract 16768: Improving Detection and Diagnosis of Rheumatic Fever in Low Resource Settings

Abstract

Introduction: Acute rheumatic fever (ARF) remains under diagnosed in low resource settings yet it is associated with dire consequences. Application of Jones criteria, the standard criteria used for diagnosis of ARF in these settings is challenging as many of its features are not readily available. Objective: To determine the performance of readily available information at each level of the healthcare system in Uganda, to determine the sensitivity and specificity of ARF diagnosis in resource limited settings. Methods: Variables that might positively or negatively predict ARF based on typical diagnostic capacity at 3 tiers of Uganda’s health system (community health center, district hospital, and national referral) were selected from a large epidemiological study conducted in northern and central Uganda. These variables were put into three statistical models to determine those that were associated with the disease. Model 1 included those variables commonly found at community health centers (features from history and clinical exam), the second model included all variables from the first model plus laboratory tests that are sometimes available (malaria antigen test, complete blood count and EKG) while the 3 rd model comprised of all variables from the 2 nd model and advanced tests that are not commonly available (ASO titers, acute phase reactants and echocardiography).Youden’s index was used to calculate sensitivity and specificity of the models and ROC curves plotted. Results: Presence of visible joint swelling and heart murmur were associated with ARF in the first and second models while carditis on echocardiogram had the highest odds ratios in the 3 rd model. Sensitivity and specificity for ARF were (51.3%, 81.0%), (60.5%, 84%) and (79.8%, 92.5%) for model 1, 2 and 3 respectively. Conclusions: Our data supports the importance of including echocardiography for the diagnosis of carditis in Jones criteria for ARF. At the same time, Jones criteria are not practical in endemic settings that not have access to definitive diagnostic testing. A new approach that is appropriate for endemic regions is therefore needed.