Clinical and Laboratory Signs as Dengue Markers During an Outbreak in Rio de Janeiro

Background  One of the main challenges for clinical research in dengue is the low validity of clinical diagnosis. Objective  To analyze clinical and laboratory data as predicitve factors of dengue diagnosis at Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation, during the 2001–2002 dengue outbreak in Rio de Janeiro. Methods  Cross sectional study comparing clinical laboratory data collected from the National Information System for Compulsory Notification Diseases (SINAN) in two serologically confirmed groups: dengue D (N = 453) and non-dengue ND (N = 80). Results  Fever, exanthema, itching, mean platelet count < 150,000, WBC count < 4,000 and absence of vomiting and of abdominal pain help to distinguish D from ND groups. When considered individually, these signs and symptoms enhance diagnostic sensitivity and, when used in combination, improve specificity. Conclusion  A combination of symptoms not necessarily considered indicative of dengue diagnosis could improve surveillance and medical decision-making in simple clinical settings.