Disaccharide Intolerance in Infancy

Abstract

In 1958 Durand published an account of an infant with vomiting and diarrhoea since birth, and he demonstrated the presence of lactose in the urine. Since that time more widespread attention has been paid to sugar intolerance in infants, and an increasing number of reports on such cases have been published.A survey of the available published material suggests that two forms of this condition exist, which from a clinical and biochemical standpoint show certain distinguishing features.In the first, diarrhoea is the presenting symptom and the occurrence of vomiting is not stressed: in these cases mellituria occurs but rarely, or not at all; where such studies have been carried out, tolerance curves utilizing the offending sugar have been flat, suggesting impairment of absorption from the intestinal lumen. The diarrhoea in these cases is deemed to be caused by the presence of large quantities of unhydrolysed and unabsorbed sugars in the intestine, and is mediated by osmotic factors or by bacterial action. Characteristically the stools are frothy, strongly acid, and have a high lactic acid content. Such cases have been described by

Lactase Deficiency and the Lactose Tolerance Test

“…Previous reports (Carson and Neely, 1963, Dahlqvist et aI, 1963, Haemmerli et aI, 1965, Kern, Struthers . and Attwood, 1963, Sheehy and Anderson, 1965 have shown wide variation both in the challenging dose of lactose and in the amount of water used to dissolve the sugar.…”

“…The figure of 2 gjkg (Carson andNeely, 1963, Cook, 1967), is considered excessive in that, for example, a child of six years weighing 20 kg would require 40 g of lactose in 800 ml of fluid, a quantity difficult for a child of this age to drink within thirty minutes. A dose of 1 g/kg would comprise 20 g of lactose in 400 ml of water; this reduced volume is more likely to give a successful test.…”

Congenital Lactose Intolerance of Gastrogen Origin Associated With Cataracts

“…Severe congenital lactose intolerance, first described in 1958 (7), is a rare disease which some authors (9,14) identify with congenital lactase deficiency, while many others (1, 5, 10-12) consider it a separate entity. The peculiar feature of severe lactose intolerance, absent in congenital lactose deficiency, is lactosuria, though other distinctive features have been recognized: signs of impaired renal function (hyperaminoaciduria, proteinuria, renal acidosis) (4, 6, 7); a self-limited natural history with return to a normal lactose absorption after brief periods of lactose-free diet (4,11) and with normal lactase activity of the intestinal hucosa after "recovery" (1,10); and a rise in the blood glucose levels after oral lactose loads even in the active phase of the disease (6,8,11).…”