Arginine vasopressin secretion in Kenyan children with severe malaria

Abstract

Hyponatraemia is common in African children with severe malaria, but the cause is unknown. We measured plasma sodium (p[Na]) and arginine vasopressin concentrations (p[AVP]) in 30 consecutive children with severe malaria (19 had cerebral malaria), on admission, at 48 and 96 h after admission. Hyponatraemia (p[Na] < 130 mmol/l) occurred in 53 per cent of the children and was unrelated to peripheral parasite density, dehydration or abnormal renal function. The highest p[AVP] were seen in patients with cerebral malaria. Overall, p[AVP] declined 96 h after treatment. In children with hyponatraemia (cerebral and non-cerebral), p[AVP] levels were not suppressed and in 67 per cent of cases they were deemed inappropriate. Inappropriate AVP secretion is common in children with severe malaria and may influence fluid therapy after correction of initial dehydration.

Sodium Disturbances in Children Admitted to a Kenyan Hospital: Magnitude, Outcome and Associated Factors

“…Previous studies performed on the Kenyan Coast have shown that over 50% of children admitted with severe malaria had hyponatremia, which is similar with this study [8, 9]. The results from that previous study [8] showed that hyponatremic children are less water depleted, often showing appropriate rather than inappropriate secretion of antidiuretic hormone.…”

“…Hyponatremia did not impair the conscious level in all children in this study, as documented in a study of children with severe malaria [19]. Cerebral salt wasting was documented in some children with cerebral malaria [8, 9], but not in this study.…”

“…Severe hyponatremia is often associated with poor outcomes including prolonged hospital stay [5], neurological deficits and death [6, 7]. There are few studies on hyponatremia in resource limited countries, where malaria is endemic and can cause perturbation in sodium levels [8, 9]. Lack of sodium level studies in these resource limited areas may lead to improper management especially with supportive fluid therapy, which should take account electrolyte concentrations [10].…”

Unidentified acids of strong prognostic significance in severe malaria*

“…Hyponatremia is a common finding in severe malaria and relates to dehydration (39). Some studies claim a role for inappropriate antidiuretic hormone secretion in severe malaria, but this is controversial (40,41). In malaria, there is a mild increase in systemic capillary permeability, which may contribute to hyponatremia by lowering plasma albumin concentrations (42).…”

Research priorities in the management of severePlasmodium falciparummalaria in children

“…Hyponatraemia is the commonest electrolyte disorder, occurring in .50% of children with severe malaria (English et al, 1996a), but its cause is unclear (English et al, 1996a;Sowunmi et al, 2000). Other electrolyte disorders include hypo-and hyperkalaemia, hypomagnesaemia and hypercalcaemia (Maitland et al, , 2005c.…”