Study to ascertain the clinical and biochemical changes that occur in dengue patients in an urban population of Sri Lanka and to identity the high-risk dengue patient

Abstract

700 patients were enrolled but those who subsequently developed signs of specific infection other than the sign of fever were, subsequently excluded from the study. Therefore, only 524 continued to be in the study. Of the 524 patients evaluated, 262 had dengue fever, 100 had dengue Hemorrhagic fever(DHF). 162 had non-dengue febrile illnesses(NDF). The symptoms at onset that were most useful for making a diagnosis of Dengue infection were, fever with rigors or fever with chills and rigors, severe vomiting, right-sided abdominal pain, faintness and coryza. In Dengue fever, a relative bradycardia was a consistent finding. In DHF, the tourniquet test (Hess's test) was a fairly sensitive diagnostic marker. Tender hepatomegaly was also a significant finding in those with DHF. Itching of either the palms or soles or a combination of both occur at the onset of the recovery phase in dengue infections. Patients with dengue and dengu hemorrhagic fever had lower white cell and absolute neutrophil counts but a higher lymphocyte count than those with NDF. Neutrphil leucocytosis was a significant observation in the NDF group. Plasma SGPT levels were higher in those who developed DHF than those with DF. In patients with dengue infections, there was a significant fall in the PC and as a significant rise in he PCV coincided with the defervescence of fever. The immunochromatographic technique using the PanBio Dengue Duo Rapid Strip showed a good sensitivity for the detection of dengue infection and enabled the differentiation between primary and secondary dengue infections. An ultrasound scan is an important adjunct to clinical and laboratory profile in diagnosing plasma leakage in dengue hemorrhagic fever. Ultrasound features of fluid around the gall bladder, pleural effusion and ascites strongly favor the diagnosis of dengue hemorrhagic fever. The above features are simple clinical and laboratory parameters that help identify those with dengue infections.