Predictors of complicated dengue infections in endemic region of Pakistan

Objective: To predict the factors associated with progression to severe dengue infection to prevent potentially fatal complications and to identify the determinants of severe complicated dengue. Methods: The study was conducted in a tertiary care hospitaldengue ward from September to November 2021 including confirmed dengue infected patients (positive NS1 antigen or anti-dengue-antibodies IgM). Secondary dengue infection was labelled by positive anti-dengue-antibodies IgG in active dengue infected patients. Detailed history, physical examination, laboratory and radiological parameters, hospital stay (days) and mortality percentages were noted. Patients were classified into three groups according to disease severity: dengue fever (DF), dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). The predictors of complicated dengue infection were determined by regression analysis. Results: The most common symptom was fever (96.9%). Among 129 patients, 62.8% had DF, 31.0% had DHF and only 6.2% developed DSS. History of previous symptomatic dengue and positive anti-dengue-antibodies IgG were present in 100% DSS patients and nearly 75.0% DHF patients (P<0.05). The moratlity rate in patients with DSS, DHF and DF was 50.0%, 2.5% and none respectively (P<0.05). Clinical parameters (body aches, bleeding, conjunctival hemorrhage, maculopapular rash, right hypochondrial tenderness, ascites, pleural effusion) and laboratory parameters (thrombocytopenia, raised alanine aminotransferase and secondary dengue infection) were determinants that complicate the dengue infection. Conclusions: Thrombocytopenia, raised alanine aminotransferase and secondary dengue infection are important laboratory parameters to complicate the disease process of dengue infection.