Familial Mediterranean Fever (FMF) can lead to various serious complications as a result of frequently recurring attacks. These complications typically begin with the accumulation of an abnormal protein called amyloid in the body (amyloidosis) and may include the following conditions:

* Amyloidosis and Organ Damage: During FMF attacks, the amyloid A protein produced can accumulate in the body and damage organs. Its accumulation, especially in the kidneys, can lead to severe kidney damage.
* Kidney Damage and Failure: Amyloidosis affecting the kidneys can cause nephrotic syndrome. This syndrome occurs when the kidney's filtering systems (glomeruli) are damaged, leading to a significant loss of protein in the urine. Nephrotic syndrome can progress to more serious problems such as blood clots in the kidneys (renal vein thrombosis) or kidney failure.
* Infertility in Women: Chronic inflammation associated with FMF can affect female reproductive organs, leading to infertility.
* Joint Pain (Arthritis): Arthritis is quite common in individuals with Familial Mediterranean Fever. The most frequently affected joints are the knees, ankles, hips, and elbows.