Acid secretion in Zulu and Indian patients with duodenal ulcers.
Pentagastrin-stimulated maximal acid output (MAO) was measured in 337 male patients with duodenal ulcers, 209 of whom were Indian, and 128 of whom were Zulus. The mean MAO standard deviation (SD) value for Zulu patients with uncomplicated ulcers was 36,2 +/- 10,5 mEq/h. In the patients with complicated ulcers, the maximal acid output was 38,5 +/- 6,3 mEq/h in patients with pyloric stenosis, 31,5 +/- 13,7 mEq/h in patients with haemorrhage and 42,9 +/- 9,2 mEq/h in patients with perforation. A statistically significant difference was obtained only in the group with perforation (Pless than0.05). The mean MAO +/- SD value for Indian patients with uncomplicated ulcers was 29,2 +/- 17,0 mEq/h. In those with complicated ulcers, the MAO value in pyloric stenosis was 30,5 +/- 5,5 mEq/h in those with haemorrhage 22,0 +/- 13,7 mEq/h and for patients with perforation, 27,8 +/- 7,5 mEq/h. A statistically significant difference in values was not obtained in Indian patients. In the Zulu patients, 77,6% had MAO values above the upper limit of normal (mean + 2 SD), while in Indian patients only 17.6% had MAO values above the upper limit of normal. The difference between the 2 percentages is highly significant (Pless than0,0001). The proportion of male patients with stimulated acid secretion measurements above the upper limit of normal in other reported series is 30-50%.