The effect of pregnancy on renal angiomyolipoma; a world of knowledge to gain, specifically in women with TSC

BackgroundWomen are counseled preconceptionally about the potential risks of rAML progression and chance of complications during and due to pregnancy. However, a systematic search investigating the evidence on which this advice is based does not exist. The aim of this systematic review is to determine the effect of pregnancy on renal angiomyolipoma (rAML) size and risk of haemorrhage in patients with tuberous sclerosis complex (TSC).MethodsWe searched PubMed, EMBASE, Medline and ClinicalTrials.gov using terms for "renal angiomyolipoma" and "pregnancy". English-language articles published between January 1st 2000, and December 31st 2020 of which full-text was available were included. The initial search resulted in 176 articles. After the screening process we included 45 case reports and 1 retrospective study. For the retrospective study we assessed the risk of bias using the Newcastle-Ottawa Scale. We included articles about renal AML and pregnancy with and without an established diagnosis of TSC. From these articles we recorded the rAML sizes and rAML complications.ResultsSeven case reports, from a total of 45 case reports, provided follow-up data on renal AML size (these were all cases of renal AML without a known diagnosis of TSC). Of these cases, renal AML size decreased in one patient, was stable in one patient, increased in three patients and fluctuated in two others. Renal AML size of women who suffered a haemorrhage were significantly larger (12.1 +/- 4.6 cm) than rAMLs of women who did not suffer a haemorrhage (8.3 +/- 3.2 cm). Data from the retrospective study showed no difference in renal complications between the women with and without a history of pregnancy. Haemorrhage occurred in 30% of the women with a history of pregnancy (n = 20) and in 11% in the patients without a history of pregnancy (n = 2), however this retrospective study had methodological limitations.ConclusionThe effect of pregnancy on renal AML size and complications in patients with TSC is unclear. More research is needed to determine the risk of pregnancy on TSC-associated kidney disease in TSC patient.