The diagnostic dilemma of a multilocular renal cyst: a case report

INTRODUCTION: Renal cysts presenting in childhood are rare. Historically, renal cysts have been subject to variable nomenclature which has contributed to diagnostic difficulties. They can occur as solitary, unilateral or multiple lesions. Cysts can be further classified according to loculation, communications within the structure and tissue types present. CASE PRESENTATION: We report the case of a 15-month-old Caucasian boy presenting with abdominal distension as the only clinical symptom. On examination, an ill-defined abdominal mass was found. This was confirmed on ultrasound to be a multiseptated cystic mass with a solid element, arising from the right side of the abdomen. Despite further imaging, the origin of the mass could not be identified. The mass was suspected of malignancy but all blood tests and tumour markers were normal. The mass proved to be a diagnostic challenge. The renal origin of the mass was only confirmed at surgery. CONCLUSION: Imaging appears to be unreliable in differentiating benign cysts from malignant renal tumours, raising a diagnostic dilemma where surgery seems the only way to reliably establish aetiology of the mass.