A family study of protracted diarrhoea in infancy.

A family study of undiagnosed protracted diarrhoea in infancy was undertaken, based on 67 such patients, seen at The Hospital for Sick Children, London, over a 6-year period. All were fully investigated with the exclusion of those with known cause, such as coeliac disease, cow's milk intolerance, or enteric infections. The families were traced and visited. The material is certainly heterogeneous. In the case of five patients the condition was associated with a syndrome. The remaining 62 index patients could be divided into a group of 15 with severe illness and 47 with a milder illness. Six had onset before one month of age, four died, and in five the diarrhoea lasted more than 12 months and the children persistently failed to thrive. These 15 severe cases had six affected sibs out of 22 (Weinberg proband method) and in all but one of these affected sibs the condition was also severe. Two further sibs had had protracted diarrhoea, but this had not been fully investigated. The 47 index patients with milder disease had 68 sibs of whom only one was affected (this boy was one of the severely affected index patients), and one other sib had protracted diarrhoea which was not fully investigated. It is proposed that the severe group includes one or more autosomal recessive entities, in which the basic defects are not yet known, but are likely to be inborn metabolic errors.