LCT and hyperinsulinemic hypoglycemia, familial, 4: The infant can suffer from watery diarrhoea after being fed with breast milk or food containing milk, and it can become a severe condition, as the shortage of nutritive ingredients can lead to growth delay, dehydration, and alkalosis; infants with congenital lactase deficiency were not expected to survive before the 20th century, when adequate lactose-free milk substitutes were not readily accessible [15]