What Causes Angiomyolipoma?

Angiomyolipoma is a benign tumor of the kidney composed of smooth muscle cells, fat, and thick vessels. While it isn't cancerous, angiomyolipoma can still grow large enough that it impairs the function of the kidney. It can also cause blood vessels to dilate and eventually burst. For some patients, rupturing of the blood vessels is the first symptom of the tumor, and it can result in hemorrhaging, pain, vomiting, and nausea. This type of tumor usually affects the kidneys, but it can also be found in the liver or sometimes other organs.

In most cases, angiomyolipoma does not require surgery unless it causes bleeding or impairs kidney function. The following are the five most common causes of angiomyolipoma.

Progenitor Cell Mutation

Angiomyolipoma is always caused by a progenitor cell mutation. Progenitor cells are cells that tend to differentiate into specific types of cells, like stem cells, but are more specific than stem cells and pushed to become their "target" cells. These cells cannot reproduce and divide indefinitely. The tumor can be associated with a disease, or it can develop sporadically, but it is always caused by mutations in the TSC1 or TSC2 genes that control cell proliferation and growth.

Angiomyolipomas are made up of immature smooth muscle cells, vascular cells, and fat cells. All three components are believed to come from a common progenitor cell that developed a "second-hit" mutation. This hypothesis states that cancer comes from accumulated mutations in the DNA.

Keep reading to learn about another serious condition that can cause this disease.

Tuberous Sclerosis

Angiomyolipoma is strongly associated with tuberous sclerosis, a genetic disease in which most individuals develop angiomyolipomas on one or both kidneys. This genetic disorder is rare and affects multiple bodily systems, causing benign tumors to develop in vital organs such as the brain, eyes, lungs, and kidneys. It can also cause other symptoms such as behavioral issues, developmental delay, intellectual delay, kidney disease, and skin abnormalities. More than fifty percent of patients with tuberous sclerosis (TS) also develop angiomyolipoma.

It is common for people with TS to require at least one form of intervention over their lifetime to treat tumors. Considering TS can impair kidney function, it is possible for the kidney to lose up to half of its function before the loss is detectable. Treatment usually involves embolization to shrink the tumor and reduce the risk of bleeding.

Continue to discover a rare illness that can cause angiomyolipoma to develop.

Neurofibromatosis

Neurofibromatosis (NF) is an uncommon condition that causes tumors to develop in the nervous system, including the spinal cord, brain, and nerves. The disorder is a group of three conditions: NF1, NF2, and schwannomatosis. NF1 causes symptoms such as tiny bumps within the nerves, freckles on the groin and armpit, brown spots on the skin, and scoliosis. NF2 can cause hearing loss, early cataracts, balance issues, and muscle wasting. Schwannomatosis is a separate form of the disease that leads to cutaneous schwannomas or benign central nervous system tumors.

NF1 is also associated with angiomyolipoma. In some cases, cutaneous angiomyolipoma can be mistaken for a neurofibroma in patients with NF. Both NF and angiomyolipoma are caused by mutations on the TSC1 or TSC2 gene.

Next, find out what rare neurological disorder is related to angiomyolipoma.

Sturge-Weber Syndrome

Sturge-Weber Syndrome or SWS is a rare neurological disorder that causes a hallmark port-wine stain on the forehead and eyelid that is usually apparent at birth. Not all children with a port-wine stain have SWS, but all patients with SWS have the hallmark port-wine stain. The disorder can also cause abnormal blood vessels, intellectual delay, cerebral malformation, seizures, and glaucoma. SWS typically occurs sporadically with no known hereditary cause.

Both SWS and angiomyolipoma are called phakomatoses, which is a group of neuro-oculo-cutaneous syndromes that affect multiple systems. Angiomyolipoma can be found with other phakomatoses including SWS and neurofibromatosis.

Keep reading to reveal which diet may cause this disorder.

High-Fat, Low Carb Diet

Sometimes a high-fat, low carb diet is prescribed to treat certain conditions. In TS patients, for example, the Ketogenic Diet is used to treat seizures, although it appears to affect tumor growth. According to a lab study, a long-term diet high in fat and low in carbohydrates can accelerate the growth and development of angiomyolipoma. Researchers also found that TS patients who followed the Ketogenic Diet as part of their treatment experienced excessive tumor growth. This is due to the long-term use of the Ketogenic Diet, which can cause renal tumors to recruit mTOR and ERK1/2 that are associated with higher levels of oleic acid and high production of the growth hormone.