Tuberous sclerosis complex renal disease

Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder affecting almost all organs. It has wider phenotypic variation than often appreciated, with less than half showing the combination of characteristic facial angiofibromas, epilepsy, and mental retardation. Renal angiomyolipomata or cysts are found in 90% and renal failure was historically a common mode of adult death from the disease. Pulmonary lymphangioleiomyomatosis is restricted to females. Angiomyolipomata or cystic disease, or both, may cause renal failure. Angiomyolipomata may also haemorrhage, especially from larger lesions. Manifestations of brain involvement substantially complicate management of many patients with TSC. The causative genes TSC1 and TSC2 encode tuberin and hamartin which are involved in control of the mammalian target of rapamycin pathway. Inhibitors of that pathway, such as sirolimus and everolimus, are therefore logical approaches to therapy and have been shown to be effective in reducing angiomyolipomata volume. It remains to be seen whether they can protect renal function.