Hypertensive posterior reversible encephalopathy syndrome in Lesch–Nyhan disease: possible contribution of chronic hyperuricemia and renin activation – a case report

<title>Abstract</title> Background Posterior reversible encephalopathy syndrome (PRES) is characterized by seizures, altered consciousness, and vasogenic edema predominantly affecting the parieto-occipital regions. Although acute hypertension is a major precipitating factor, impaired cerebral autoregulation and endothelial dysfunction are also considered to contribute to its pathophysiology. Lesch–Nyhan disease (LND) is a rare X-linked disorder caused by hypoxanthine–guanine phosphoribosyltransferase deficiency and is associated with chronic hyperuricemia and severe neurological manifestations. Hypertension has rarely been described in association with LND. Case presentation We report a 4-year-old boy with genetically confirmed LND who developed hypertensive PRES during status epilepticus. On admission, his blood pressure was markedly elevated (207/101 mmHg). Neurological symptoms improved promptly after antihypertensive therapy. Brain magnetic resonance imaging demonstrated bilateral occipital subcortical hyperintensities on T2-weighted and fluid-attenuated inversion recovery images. Echocardiography revealed left ventricular hypertrophy. Plasma renin activity was elevated prior to initiation of angiotensin-converting enzyme inhibitor therapy. No structural renal abnormalities were detected. Conclusions This case suggests that chronic hyperuricemia-related vascular dysfunction, including cerebral vascular endothelial vulnerability, together with activation of the renin–angiotensin system, may increase susceptibility to the development of hypertensive PRES.