Mevalonate kinase deficiency is a condition characterized by recurrent episodes of fever, which typically begin during infancy. Each episode of fever lasts about 3 to 6 days, and the frequency of the episodes varies among affected individuals. In childhood the fevers seem to be more frequent, occurring as often as 25 times a year, but as the individual gets older the episodes occur less often.\n\nMevalonate kinase deficiency has additional signs and symptoms, and the severity depends on the type of the condition. There are two types of mevalonate kinase deficiency: a less severe type called hyperimmunoglobulinemia D syndrome (HIDS) and a more severe type called mevalonic aciduria (MVA).\n\nDuring episodes of fever, people with HIDS typically have enlargement of the lymph nodes (lymphadenopathy), abdominal pain, joint pain, diarrhea, skin rashes, and headache. Occasionally they will have painful sores called aphthous ulcers around their mouth. In females, these may also occur around the vagina. Rarely, people with HIDS develop a buildup of protein deposits (amyloidosis) in the kidneys that can lead to kidney failure. Fever episodes in individuals with HIDS can be triggered by vaccinations, surgery, injury, or stress. Most people with HIDS have abnormally high levels of immune system proteins called immunoglobulin D (IgD) and immunoglobulin A (IgA) in the blood. It is unclear why some people with HIDS have high levels of IgD and IgA and some do not. Elevated levels of these immunoglobulins do not appear to cause any signs or symptoms. Individuals with HIDS do not have any signs and symptoms of the condition between fever episodes and typically have a normal life expectancy.\n\nPeople with MVA have signs and symptoms of the condition at all times, not just during episodes of fever. Affected children have developmental delay, problems with movement and balance (ataxia), recurrent seizures (epilepsy), progressive problems with vision, and failure to gain weight and grow at the expected rate (failure to thrive). Individuals with MVA typically have an unusually small, elongated head. In childhood or adolescence, affected individuals may develop eye problems such as inflammation of the eye (uveitis), a blue tint in the white part of the eye (blue sclera), an eye disorder called retinitis pigmentosa that causes vision loss, or clouding of the lens of the eye (cataracts). Affected adults may have short stature and may develop muscle weakness (myopathy) later in life. During fever episodes, people with MVA may have an enlarged liver and spleen (hepatosplenomegaly), lymphadenopathy, abdominal pain, diarrhea, and skin rashes. Children with MVA who are severely affected with multiple problems may live only into early childhood; mildly affected individuals may have a normal life expectancy.

Disease with characteristics of early-onset severe polycystic kidney disease with various manifestations of tuberous sclerosis (multiple angiomyolipomas, lymphangioleiomyomatosis and periventricular calcifications of the central nervous system). A contiguous gene syndrome caused by a large deletion involving both the PKD1 and TSC2 genes (16p13.3). Transmission is autosomal dominant.

Tuberous sclerosis complex (TSC) involves abnormalities of the skin (hypomelanotic macules, confetti skin lesions, facial angiofibromas, shagreen patches, fibrous cephalic plaques, ungual fibromas); brain (subependymal nodules, cortical tubers, and subependymal giant cell astrocytomas [SEGAs], seizures, intellectual disability / developmental delay, psychiatric illness); kidney (angiomyolipomas, cysts, renal cell carcinomas); heart (rhabdomyomas, arrhythmias); and lungs (lymphangioleiomyomatosis [LAM], multifocal micronodular pneumonocyte hyperplasia). Central nervous system tumors are the leading cause of morbidity and mortality; renal disease is the second leading cause of early death.

Tuberous sclerosis complex (TSC) involves abnormalities of the skin (hypomelanotic macules, confetti skin lesions, facial angiofibromas, shagreen patches, fibrous cephalic plaques, ungual fibromas); brain (subependymal nodules, cortical tubers, and subependymal giant cell astrocytomas [SEGAs], seizures, intellectual disability / developmental delay, psychiatric illness); kidney (angiomyolipomas, cysts, renal cell carcinomas); heart (rhabdomyomas, arrhythmias); and lungs (lymphangioleiomyomatosis [LAM], multifocal micronodular pneumonocyte hyperplasia). Central nervous system tumors are the leading cause of morbidity and mortality; renal disease is the second leading cause of early death.

Multiple endocrine neoplasia is a group of disorders that affect the body's network of hormone-producing glands called the endocrine system. Hormones are chemical messengers that travel through the bloodstream and regulate the function of cells and tissues throughout the body. Multiple endocrine neoplasia typically involves tumors (neoplasia) in at least two endocrine glands; tumors can also develop in other organs and tissues. These growths can be noncancerous (benign) or cancerous (malignant). If the tumors become cancerous, the condition can be life-threatening.\n\nThe major forms of multiple endocrine neoplasia are called type 1, type 2, and type 4. These types are distinguished by the genes involved, the types of hormones made, and the characteristic signs and symptoms.\n\nThe most common sign of multiple endocrine neoplasia type 2 is a form of thyroid cancer called medullary thyroid carcinoma. Some people with this disorder also develop a pheochromocytoma, which is an adrenal gland tumor that can cause dangerously high blood pressure. Multiple endocrine neoplasia type 2 is divided into three subtypes: type 2A, type 2B (formerly called type 3), and familial medullary thyroid carcinoma (FMTC). These subtypes differ in their characteristic signs and symptoms and risk of specific tumors; for example, hyperparathyroidism occurs only in type 2A, and medullary thyroid carcinoma is the only feature of FMTC. The signs and symptoms of multiple endocrine neoplasia type 2 are relatively consistent within any one family.\n\nMultiple endocrine neoplasia type 4 appears to have signs and symptoms similar to those of type 1, although it is caused by mutations in a different gene. Hyperparathyroidism is the most common feature, followed by tumors of the pituitary gland, additional endocrine glands, and other organs.\n\nMany different types of tumors are associated with multiple endocrine neoplasia. Type 1 frequently involves tumors of the parathyroid glands, the pituitary gland, and the pancreas. Tumors in these glands can lead to the overproduction of hormones. The most common sign of multiple endocrine neoplasia type 1 is overactivity of the parathyroid glands (hyperparathyroidism). Hyperparathyroidism disrupts the normal balance of calcium in the blood, which can lead to kidney stones, thinning of bones, nausea and vomiting, high blood pressure (hypertension), weakness, and fatigue.