Cosegregation of familial intestinal pseudoobstruction and presence of digital arches in a large multigenerational pedigree.

Previous studies have suggested a relationship between the presence of digital arches and the occurrence of early-onset chronic intestinal pseudoobstruction (CIP). We recently had under our care a patient who died of complications from neuropathic familial CIP (FCIP) and who had family members with symptoms and radiographic findings consistent with FCIP. Our aim was to determine if there is a relationship between FCIP and digital arches using members of this patient's family tree. Questionnaires, telephone follow-up, and clinical and radiographic evidence were all utilized to determine whether a diagnosis of CIP could be made for the family members of this deceased FCIP patient. Fingerprints were sought for all study subjects. Eight of the 26 study subjects who were fingerprinted had clinically diagnosed FCIP and four of these eight had radiographic confirmation. All eight were positive for one or more arches (sensitivity = 100%). Only one of the 18 subjects without a diagnosis of FCIP who were fingerprinted had arches (specifically 94%). The likelihood of linkage between the presence of digital arches and FCIP in our study family was significant by genetic linkage analysis criteria. These results show a significant correlation between FCIP and digital arches (P < 0.0001). Whether this relationship is a causal one, ie, the gene responsible for digital arches is also responsible for FCIP, or is the result of linkage between the genes for FCIP and digital arches remains unclear.