Very large AVMs cause a marked inability to absorb oxygen, which may be noted by cyanosis (bluish discoloration of the lips and skin), clubbing of the fingernails (often encountered in chronically low oxygen levels), and a humming noise over the affected part of the lung detectable by stethoscope.The symptoms produced by AVMs in the liver depend on the type of abnormal connection that they form between blood vessels. If the connection is between arteries and veins, a large amount of blood bypasses the bodys organs, for which the heart compensates by increasing the cardiac output. Eventually congestive cardiac failure develops ("high-output cardiac failure"), with breathlessness and leg swelling among other problems. If the AVM creates a connection between the portal vein and the blood vessels of the liver, the result may be portal hypertension (increased portal vein pressure), in which collateral blood vessels form in the esophagus (esophageal varices), which may bleed violently; furthermore, the increased pressure may give rise to fluid accumulation in the abdominal cavity (ascites). If the flow in the AVM is in the other direction, portal venous blood flows directly into the veins rather than running through the liver; this may lead to hepatic encephalopathy (confusion due to portal waste products irritating the brain). Rarely, the bile ducts are deprived of blood, leading to severe cholangitis (inflammation of the bile ducts). Liver AVMs are detectable in over 70% of people with HHT, but only 10% experience problems as a result.In the brain, AVMs occasionally exert pressure, leading to headaches.
This can affect both genders and includes a variety of manifestations of varying severity. Type 3: Autoimmune manifestations primarily limited to the GI tract. This can affect both genders and may also be considered IPEX-like. There is considerable overlap in these disorders, and it is often unclear how to properly distinguish between them as the responsible genes are generally poorly understood at this time. Treatment
Medical therapy is commonly used, most typically with corticosteroids (budesonide and prednisone). However, some patients are refractory to corticosteroids, and in these patients immunosuppressive therapy with azathioprine, cyclophosphamide, tacrolimus, cyclosporine and infliximab has been described. An intravenous nutrition such as total parenteral nutrition and/or a special diet may be necessary. Hematopoietic stem cell transplantation may be curative. References
Further reading
Montalto, Massimo; DOnofrio, Ferruccio; Santoro, Luca; Gallo, Antonella; Gasbarrini, Antonio; Gasbarrini, Giovanni (January 2009). "Autoimmune enteropathy in children and adults". Scandinavian Journal of Gastroenterology. 44 (9): 1029–1036. doi:10.1080/00365520902783691. PMID 19255930. S2CID 33004674. "Autoimmune Enteropathy". Cincinnati Childrens.