The differential diagnosis of hypernatraemia in children, with ...

The Diagnosis of Salt Poisoning Leading to Hypematraemia in Children – September 2009
4.2.4 Accidental or voluntary ingestion by children
Sodium, mainly in the form of salt, is a necessary component of children’s diet. Sodium
intakes by healthy children have been assessed in a number of studies, including two from
the UK in 1986.
The first study from Southampton 214 used 24-hour urinary sodium excretion as a marker
of intake in 28 children aged 3 to 5 years registered with a single general practice. Their
sodium intake was also estimated by analysis of 3-day food diaries. The average daily
excretion of sodium was 65 mmol, or 3.5 mmol/kg (range 28 to 105 mmol, or 1.6 to 6.2
mmol/kg). Analysis of the food diaries suggested a mean daily sodium intake of 69 mmol
(range 32 to 98 mmol).
The second study from London 215 obtained two 24-hour urine samples from 34 children
aged 4 to 6 years attending two primary schools. The mean urinary sodium excretion
was 64 mmol (range 20.5 to 131 mmol). Neither study calculated fractional sodium
excretion rates.
The specific question relevant to the differential diagnosis of hypernatraemia is whether an
otherwise healthy child will spontaneously and voluntarily consume sufficient salt to cause
them to become hypernatraemic. There are two sources of evidence to assist in answering
this question. The first is a national database originally developed by the Department for
Trade and Industry, subsequently transferred to the Royal Society for the Prevention of
Accidents (RoSPA). The second is the identification of all relevant case reports.
The national database held by RoSPA is collected as part of the Home and Accident
Surveillance System (HASS) and Leisure Accident Surveillance System (LASS). 216 The
resulting database holds details of home and leisure accidents that caused a serious enough
problem to warrant a visit to hospital. The data were collected by regular sampling from
each of the same representative UK hospitals from 1978 to 2002 (18 centres before 2001
and 16 centres thereafter). DTI data collection stopped with the publication of the 24 th
Report in 2003 217 and the entire database was transferred to RoSPA who have made it
available to users.
Over the 25-year period 1978-2002, 45,767 instances of suspected poisoning in children
aged 0-4 years were sampled (about 8.5% of the estimated total national occurrences of
poisoning for this age range over the same period). There were 8 recorded instances of
accidental salt ingestion in children aged 0-4 years over this time. 218 Details of these cases
are reproduced below:
47