Pathophysiological clinical features of an infant with hypertension secondary to multicystic dysplastic kidney: a case report

BACKGROUND: The association of hypertension with congenital renal hypoplasia has been established. We report a case of an infant who underwent nephrectomy for hypertension. CASE PRESENTATION: Magnetic resonance imaging for the mother revealed fetal renal masses, and fetal multicystic dysplastic kidney was suspected. Following birth, the baby developed hypertension. Numerous investigations revealed that the left kidney was non-functional, and she was initiated on benazepril hydrochloride. However, because the drug response was poor, the left kidney was removed at the age of 7 months. Examination of the renal specimen revealed abrupt transition from normal to atrophic cortex with lobar atrophy and cysts. Tubular atrophy, marked abnormal blood vessels with wall thickening, gathered immature glomeruli, and parenchymal destruction were observed. Renin was partially localized in the proximal tubules and the parietal epithelium of the Bowman’s capsule in the immature glomeruli. We speculated that an abnormal vascular structure and irregular renin localizations may be the cause of hypertension. Serum renin and aldosterone levels gradually reduced post-surgery, reaching normal levels on the 90th postoperative day. A long follow-up is needed due to the possibility of the child developing hypertension in the future. CONCLUSION: This is a case of an infant with MCDK, which discusses the clinicopathological features based on the pathophysiological analysis, including renin evaluation.