Is the incidence of gastroschisis rising in South Africa in accordance with international trends? A retrospective analysis at Pretoria Academic and Kalafong Hospitals, 1981-2001.

OBJECTIVES: Analysis of the incidence of gastroschisis compared with the incidence of exomphalos as a percentage of total paediatric surgical admissions. DESIGN: Retrospective observational analysis using data from the ward admissions registers of the paediatric surgical wards of Pretoria Academic and Kalafong hospitals and from the weekly statistics sheets and audits thereof of the Paediatric Surgery Department at Pretoria Academic Hospital. Patient files from Pretoria Academic were used where available to confirm data. SETTING: Pretoria Academic Hospital (PAH) and Kalafong Hospital (KH), Pretoria, from March 1981 to December 2001, excluding Kalafong Hospital data from February 1984 to 12 June 1984 and for 2001. RESULTS: Forty-eight cases of gastroschisis and 139 cases of exomphalos were seen at PAH and KH out of 21 495 total paediatric surgery ward admissions. The average incidence of gastroschisis increased 35-fold from the 7-year period 1981 - 1987 to the 7-year period 1995 - 2001, while the average incidence of exomphalos compared across the same periods only showed a 1.82-fold increase. The incidence of gastroschisis rose above that of exomphalos in 1999 and remained so through to 2001. The incidence of exomphalos showed a general rising trend from 1981 to 2001 except for a sudden unexplained increase in 1995 and 1996. Gastroschisis presenting at PAH was associated with a mortality rate of at least 38.7%. Reasons for this high mortality rate cannot be adequately evaluated owing to poor record keeping. CONCLUSIONS: The incidence of gastroschisis presenting at PAH and KH has risen dramatically relative to the incidence of the macroscopically similar exomphalos over the period 1981 - 2001, with the incidence of gastroschisis rising above the incidence of exomphalos. A larger scale study looking at birth prevalence of gastroschisis and exomphalos in South Africa is necessary to determine whether this represents a true differential change in the incidence of gastroschisis, reflecting internationally observed increases in the birth prevalence of this defect, or whether it is merely due to logistical changes within the administration of the Department of Health serving the area.