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Pseudohypoaldosteronism type 1B (PHA type 1B) is a very rare multi-system salt-wasting disease. Severe life-long salt loss is seen in multiple target organs expressing the amiloride-sensitive epithelial sodium channel (ENaC) including the kidney, sweat glands, salivary glands, colon and lung. In the lungs, ENaC channels are located on the motile cilia and regulate the osmolarity of the periciliary liquid, necesarry for a normal motile cilia function. The loss-of- function of ENaC in PHA type 1B patients leads to an increase in the airway surface liquid (ASL), resulting in ‘intrapulmonary drowning’. Patients present with recurrent episodes of chest congestion, coughing, and wheezing. Despite the different pathophysiology, this pulmonary syndrome with increased sweat and saliva electrolyte can easily be confused with cystic fibrosis (CF). We report a case of PHA type 1B with a very severe respiratory phenotype. Reviewing all other PHA type 1B patients with respiratory symptoms, it seems that our patient presents the most severe respiratory course ever described. Up to now, the pulmonary phenotype in PHA type 1B can not be predicted. Nevertheless, it would be useful for the follow-up of these patients, resulting in a better long-term prognosis. To our knowledge, a respiratory comorbidity like asthma could be such a predictor. More research is needed on this topic.