...sounds like he may have had secondary pseudohypoaldosteronism which sounds as if it is due to a blockage and that is resolved?  Or is it a mineral imbalance that causes a blockage? 

Sounds like there is treatment though:

 

• Renal PHA-I: Patients with renal PHA-I have a characteristic lack of improvement despite administration of large doses of mineralocorticoids. Therapy consists of fluid and sodium supplementation, with requirements being higher early in infancy and tending to diminish over time. Large doses may be necessary to correct serum electrolyte abnormalities. Sodium chloride supplementation is followed by significant clinical improvement and correction of electrolyte abnormalities. Expansion of ECF will increase the renal tubular flow and sodium chloride delivery to the distal nephron, thus creating a favorable gradient for secretion of potassium despite the lack of mineralocorticoid action.

• MTOD PHA-I: Although administration of exogenous mineralocorticoids is ineffective in correcting the abnormalities in this disorder, ingestion of a high sodium and low potassium diet generally is effective in preventing volume depletion and in partially reducing, but not completely correcting, the hyperkalemia. Patients may require oxygen for episodes of dyspnea and cyanosis associated with lower respiratory tract infections.

• PHA-II: Restriction of dietary sodium in some patients has resulted in normalization of blood pressure, plasma potassium, aldosterone, renin, and urinary calcium levels. Correction of acidosis with bicarbonate, however, does not correct the hyperkalemia.