The 2011 dengue haemorrhagic fever outbreak in Lahore - an account of clinical parameters and pattern of haemorrhagic complications.

Abstract

To describe the frequency and outcome of dengue haemorrhagic fever (DHF) cases and determine the association of clinical and laboratory parameters with haemorrhagic complications. A descriptive study. Combined Military Hospital, Lahore, from August to November 2011. Clinical profile and outcome of 640 adult patients hospitalized with a strong clinical suspicion of dengue fever (DF) was evaluated. Based on serological confirmation, these patients were divided into confirmed DF and probable DF cases. They were also categorized according to severity into dengue fever (DF), dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS) cases according to WHO guidelines. After detailed clinical evaluation, blood samples were taken for a complete blood count, urea, creatinine, sodium, potassium, bilirubin, alanine aminotransferase (ALT), prothrombin time (PT) and activated partial thromboplastin time (APTT). Patients were managed according to standard protocols with intravenous fluids and symptomatic treatment. SPSS 18 was used for statistical analysis of clinical data. Comparison of features among the groups was made using chi-square or t-test with significance at p < 0.05. There was 359 probable DF and 281 confirmed DF cases. The development of DHF, neurological manifestations and overall mortality was more frequent in confirmed DF group. Comparison between DHF/DSS and DF cases revealed a significant difference in vomiting (p = 0.04), purpuric rash (p < 0.001), systolic blood pressure (p = 0.002), serum ALT (p < 0.001), hospital stay (p < 0.001), neurological involvement (p < 0.001) and coagulopathy (p < 0.001) between the two groups. Among 159 DHF patients, 108 (67.9%) had bleeding from gums and oral cavity, 73 (45.9%) had haemetemesis and 82 (51.5%) malaena, 41 (25.8%) had epistaxis, 12 (7.5%) developed intracranial bleeding, 18 (11%) had hematuria, 12 (7.5%) had fresh bleeding per rectum and 37 (23%) developed haemoptysis. Overall mortality was 3%, but mortality in DHF/DSS cases was 6% and 41.6% for DSS cases. Logistic regression analysis showed that abdominal pain, purpuric rash, ascites, thrombocytopenia, coagulopathy and raised ALT had a statistically significant predictability for developing DHF. A variety of manifestations including that abdominal pain, purpuric rash, ascites, thrombocytopenia, coagulopathy and raised ALT had a statistically significant predictability for developing DHF. A knowledge and understanging of these complictions would be useful for the management of patients if such outbreaks of DHF are encountered again.