A Novel Mutation in Cystic Fibrosis Presenting as Pseudo Bartter Syndrome: A Case Report.

Pseudo-Bartter's (PB) syndrome is characterized by hypokalemic metabolic alkalosis and failure to thrive which constitutes a rare but typical presentation of cystic fibrosis (CF) in children. The most common mutation of CF is F508del, due to loss of 3 base pairs, causing deletion of phenylalanine, at position 508. We present a case of CF presenting with failure to thrive, dehydration, PB syndrome associated with urosepsis and primo-colonization with Escherichia coli suggesting the role of epigenetic factors. The heterozygous state for Phe508del mutation in Exon 11 combination with Glu92Ala in Exon 4 resulted in epigenetic effect on atypical phenotype as PBS, a novel mutation identified in our case.