The Usefulness of Computerized Scoring System for Assessing the Severity and Outcome of Therapy in Patients with Dengue Infection

Introduction: The clinical manifestations of dengue infection range from asymptomatic infection, undifferentiated fever, an influenza-like symptom as dengue fever (DF) to a severe, sometimes fatal disease characterized by hemorrhage and shock known as dengue hemorrhagic fever (DHF). In mild degrees of DHF (WHO grades I and II), the changes in the vital signs are minimal and transient while the severe degrees (WHO grades III and IV), also known as dengue shock syndrome (DSS), the blood pressure ranges from narrowing pulse pressure (<20 mmHg) with a characteristically elevated diastolic pressure (e.g. 100/90 mmHg) to profound shock. Bleeding diathesis is caused by vasculopathy, thrombocytopenia and coagulopathy. Vasculopathy resulting in plasma leakage is significantly found during the end of febrile stage and the toxic stage when an abrupt fall to normal or subnormal temperature occurs. The evidence of plasma leakage is manifested by hemoconcentration, hypoproteinemia, pleural effusion, ascites and shock. The toxic stage lasts 24–48 hours followed by the uneventful convalescent stage in the majority of patients. Therapy of DHF is wholly symptomatic and aims at controlling the clinical manifestations of bleeding and shock. The rate and volume of fluid replacement should be adjusted according to the rate of plasma leakage as guided by hematocrit, vital signs and urine output. Frequent monitoring of vital signs, hematocrit and urine output is necessary for evaluating the outcome of therapy. Patients who do not receive the appropriate treatment usually die within 12–24 hours after the occurrence of shock. Prolonged shock is often complicated with metabolic acidosis that may precipitate disseminated intravascular coagulation (DIC) or enhance the ongoing DIC to aggravate massive bleeding. The close monitoring of clinical manifestations and results of laboratory tests by the attending physicians and nurses is essential for favorable outcome.

Methods: A computerized program of scoring system for assessing the clinical manifestations and outcome of management in patients with dengue infection, was created. It was written by Microsoft Access. Sixteen items involving vital signs of pulse rate, blood pressure, duration to achieve the pulse pressure ≥ 20 mmHg, urine output; number of bleeding site; amount of required crystalloid, colloid, packed red cells and platelet concentrate; manifestations of hepatic failure, encephalopathy, respiratory distress syndrome, reshock or requiring inotropic drugs; as well as the requirement of central line application, ventilator or dialysis, were included. The scores of 3 to 10 were given to each item with a total score of 100. The scores in each item was also classified by the severity of clinical manifestations according to the patient’s age. The higher scores were given to a more severe manifestation. The total scores would be automatically shown on the computerized screen when the clinical data input was added.

Results: The scoring system was retrospectively and prospectively applied to children with dengue infection whose ages ranged from 5–15 years. All patients had positive dengue-specific IgM and IgG antibodies in the acute and convalescent sera determined by capture ELISA technique. The results revealed that the scores increased accordingly with the severity of the manifestations (DF 0–10, DHF grade I 5–15, grade II 10–25, Grade III 20–50, grade IV 40–75 and DSS with reshock or uncontrolled bleeding 50–100). The case-fatality was found in patients with higher scores of 75–100.

Conclusion: The computerized scoring system for assessing the severity of patients with dengue infection is helpful in the clinical practice especially for the management of high risk patients with severe degree or DSS.