An unusual case of Pseudohypoaldosteronism coexisting with cystic fibrosis

Pseudohypoaldosteronism type 1 is a rare congenital autosomal recessive disorder, characterised by failure of receptor response to aldosterone. It is caused by mutation in SCNN1A gene with clinical features like failure to thrive in infancy, hyponatraemia, hyperkalaemia and metabolic acidosis. We present a male infant with seizures, hyperkalaemia and with failure to thrive, diagnosed at day 6 of life. The baby required repeated correction for hyperkalaemia; hence, after ruling out treatable causes for hyperkalaemia, exonerated sequencing was done which showed pathogenic mutation for cystic fibrosis and recessive mutation for pseudohypoaldosteronism. But the child was clinically in favour of pseudohypoaldosteronism. Hence, features of pseudohypoaldosteronism predominate cystic fibrosis; they both may coexist.