Spontaneous Retroperitoneal Haemorrhage From Bilateral Renal Angiomyolipomas: A Case Report on a First Presentation of Tuberous Sclerosis Complex

Renal angiomyolipomas (AMLs) are benign mesenchymal tumours that may present with life-threatening haemorrhages when associated with underlying genetic conditions. AMLs are comprised of mature but disorganised vasculature, smooth muscle and fatty adipose tissue. Whilst the majority of intrarenal AMLs are sporadic and found incidentally as solitary lesions, there is a significant association with tuberous sclerosis complex (TSC). TSC results in the disruption of the mTOR pathway, leading to unregulated cell proliferation and subsequent benign tumour growth. Consequently, AMLs present in TSC are typically large, multiple and complex in nature. In this case, we report a 22-year-old woman with no significant past medical history, who presented with right‑sided abdominal pain and was initially investigated for cholecystitis. Imaging revealed bilateral renal AMLs, a right renal artery pseudoaneurysm and acute retroperitoneal haemorrhage. The patient was stabilised with a transfusion and proceeded to undergo emergency super‑selective embolisation. Physical examination and radiological clues raised further suspicion of TSC. Follow-up interval imaging revealed a 9 mm intra-tumoral aneurysm in the contralateral kidney, which was prophylactically embolised, and neuroimaging revealed subependymal nodules. Subsequent treatment is anticipated to involve pharmaceutical mTOR inhibition, definitive neurological assessment and follow-up at the regional Genetics Centre. In patients with complex AMLs and clues of genetic disease, evaluation for TSC should be prompt. The presence of secondary features should raise suspicion and initiate assessment of underlying genetic conditions in young patients. Evaluation may then unmask serious complications, such as haemorrhage, and early recognition enables targeted intervention, surveillance and holistic patient counselling.