Serum ionic calcium levels and hypocalcemia in dengue fever in children and its correlation with its severity: case control study

Abstract

Background: Dengue fever (DF) is a major health problem, 90% of dengue hemorrhagic fever (DHF) occurring in children <5 years and mortality of 2.5%. Abnormalities like metabolic acidosis, hyponatremia and hypocalcemia can occur in severe dengue especially in dengue shock patients. Alterations in calcium homeostasis, may play a role in the pathogenesis of dengue shock. Objectives is to evaluate serum ionic calcium (Ca2+) levels in children aged 1-18yrs with dengue fever and correlate it with severity and outcomeMethods: The study was prospective hospital based case-control study. Case group had 75 children with dengue fever with equal number of controls. Cases were classified according to WHO classification. Serum Ca2+ levels were estimated within 24 hours of admission.Results: Majority of children with dengue were in the age-group of 6-15 years (71.4%). Out of 75 cases,16% were dengue without warning signs, 54.7% dengue with warning signs and 29.3% were severe dengue cases. Mean Ca2+ level (in mmol/l) was 1.2009 (±0.09) among controls and 1.0911 (±0.10) in dengue cases (p=0.0001). Mean Ca2+ level in dengue without warning signs was 1.0950 mmol/l, dengue with warning signs was 1.1088 mmol/l and severe dengue was 1.0559 mmol/l. Mean Ca2+ level in severe dengue was significantly lower compared to dengue with warning signs (p=0.04). Hypocalcemia was seen in 56% of dengue cases but only 14% among controls. Seven children with severe dengue who died had hypocalemia.Conclusions: Hypocalcemia is common in dengue fever. Lower levels of ionic calcium correlate with severity of dengue illness and may be considered as a prognostic indicator of poor outcome.