We present 2 cousin brother and sister, MK and AK (family tree attached in Fig) who presented with a common pattern of hyponatremia with hyperkalemia, hypomagnesaemia, salt wasting, hyperaldosterinism and hyper-reninaemia in their neonatal life with polyuria. A diagnosis of pseudohypoaldosteronism was made and they were commenced on sodium supplements and indomethacin.
The shaded boxes are in utero deaths. MK and AK are the other off springs.
The cousin sister later developed UTI when she was found out to have nephrocalcinosis and calcuria, which are unheard of in pseudohypoaldosteronism There are however reports of neonatal Bartters also presenting with hyperkalemia metabolic acidosis which usually reverts after 46weeks of life and shifts to a picture of hypokalaemic metabolic alkalosis, with hyperreninaemia, hyperaldosterinism. Nephrocalcinosis is documented in Bartters but not in pseudohypoaldosteronism. Further investigations proved that both have got neonatal Barters syndrome as a result of de novo mutations for the ROMK gene.
The genetic basis of Bartters relates a defect in NaCl transport in the distal nephron. Two molecular defects have been identified: Either bumetanide-sensitive Na-K-2CL cotransporter (NKCC2) or the adenosine triphosphate-sensitive inwardly-rectifying K channel (ROMK). Our Patients demonstrate a ROMK gene defect. Patients with the ROMK channel gene defects are especially sensitive to indomethacin and hence important factor for the long-term management.
05 - 07 Nov 2008
British Society for Paediatric Endocrinology and Diabetes