A descriptive cross-sectional study to assess the changes in urine output, urine osmolality and proteinuria in critical phase of dengue; Interim Analysis

Abstract

Annually, approximately 50-100 million individuals are infected with dengue and two to three billion people are at risk of developing Dengue Fever (DF). Dengue causes a spectrum of disease, ranging from a mild febrile illness to a life-threatening dengue hemorrhagic fever and dengue shock syndrome. The classical features of dengue infection are high-grade fever, headache, retro orbital pain, arthralgia and myalgia, vomiting, sore throat, and maculopapular rash. The initial stage of DF is febrile phase followed by critical or leaking phase and finally the convalescent phase. The main clinical features which are detected at the time of plasma leakage is haemoconcentration detected by packed cell volume, a sudden drop of platelet count and the reduction of urine output. As the haemoconcentration can be controversial where the patient is having concealed bleeding, the practical clinical sign of detecting leakage is the sudden reduction of platelet count and the urine output. Renal involvement in dengue is one of the complications identified. It can range from mild proteinuria to acute renal failure in severe dengue haemorrhagic fever. This study is planned to detect the time at which the renal functions are deranged in DF, by detecting the changes that occur in urine and serum. A descriptive cross-sectional study is being conducted at the medical wards of Provincial General Hospital-Kurunegala. All the patients diagnosed with DF were recruited for the cohort. Demographic data, duration of illness on admission and presenting clinical manifestations, were obtained using an interviewer administered questionnaire before discharging the patient from the ward. The recorded data in BHT and the data of the attachments of BHT on selected investigations were extracted into a data extraction sheet. On admission, all patients with DF investigated for baseline tests of serum creatinine, urine osmolality, urine protein, and urine glucose. Further, the diagnosis was confirmed with serological testing. Once the patient enters into leaking phase, 6 hourly urine samples was taken for urine osmolality and urine protein and a serum sample was obtained for serum creatinine. On discharge a urine sample and a serum sample was obtained for above mentioned tests. From the recruited 51 patients, 9 patients were excluded due to incomplete data. The sample consists of 36 non-leaking and 8 leaking patients up to now. Majority of the patients were in 20- 29 years’ age group (31%) and females (76.2%). According to current literature, DF is more common among males and young age group in Sri Lanka. Majority of the patients were Sinhalese (92.9%) and educated up to GCE O/L (38.1%). In accordance with the literature, patients fromfamilies with low income levels were predominant (57.1%) and that may be due to poor environmental conditions of the houses. From the onset of the disease, 42.9% of the patients had fever whilst 2.4% of the patients had no fever. Major signs and symptoms of the disease were generalized body ache (61.9%), myalgia (54.8%), anorexia (50%), headache (45.2%), arthralgia (35.7%), sore throat (19%), nausea (16.7%), vomiting (7.1%), and retro orbital pain (2.4%). Diabetes mellitus and hypertension were reported as comorbid conditions for 11.9% and 7.1% of patients respectively. Contact history was not reported in majority of patients (61.9%). As per the hypothesis postulated at the inception of the study, it reveals that there is a discrepancy in the renal water conservation at the time of reduced urine output (Figure:1). Four out of five patients showed a reduction in the urine osmolality with the reduction in urine output without a change in the fluid input. At the same time, there was a transient proteinuria during the leaking period of dengue. Although the number of cases tested is not adequate to postulate a theory, it is quite obvious that the renal tubular and glomerular functions are affected in the early stages of the dengue infection and it can lead to long-term effects unidentified. With the available data up to now, it can be proven that, the renal involvement in dengue fever comes early in the disease process and it may need to adopt reno-protective management strategies in managing even mild cases of dengue fever without overburdening the renal parenchyma. We would like to acknowledge for Wayamba University for providing support for this study.