This case report describes a premature male infant born after a pregnancy complicated by oligohydramnios of unknown aetiology but otherwise unremarkable prenatal scans. He had sudden onset of projectile emesis and severe hypertension in the third week of life, and further investigations revealed both pyloric stenosis and polycystic kidneys, at just 36 weeks' postmenstrual age (PMA). His course thereafter was complicated by severe refractory hypertension requiring multiple antihypertensive agents in order to gain control, although his renal function remained normal. Few case reports have previously described this unusual association, but none have presented with both entities at such an early PMA.
