Focal alopecia congenital - megalencephaly: A very rare syndrome characterized mainly by patchy hair loss which has no associated inflammation and scarring of the scalp. Megalencephaly (large, heavy brain) is also present.
Focal cortical dysplasia is a malformation of cortical development, which is the most common cause of medically refractory epilepsy in the pediatric population and the second/third most common etiology of medically intractable seizures in adults.
There are several types of FCD based on the particular microscopic appearance and associated other brain changes:
FCD Type I: the brain cells have abnormal organization in horizontal or vertical lines of the cortex. This type of FCD is often suspected based on the clinical history of the seizures (focal seizures which are drug-resistant), EEG findings confirming focal seizure onset, but is often not clearly seen on MRI. Other studies such as PET, SISCOM or SPECT and MEG may help point to the abnormal area which is generating seizures, but FCD Type I is often only confirmed after that area of the seizure-generating area of the brain has been resected and is then examined under the microscope.
FCD Type II: when, in addition to abnormal organization, the brain cells themselves look abnormal, with “dysmorphic neurons” or “balloon cells.” FCD type II typically presents in early childhood and is usually seen on MRI.
FCD type III: when in addition to either of the above findings, there is another associated abnormality such as hippocampal atrophy, tumors, stroke or traumatic brain damage.
Focal cortical dysplasia (FCD) is found in approximately one-half of patients with medically refractory epilepsy. These lesions may involve only mild disorganization of the cortex, but they may also contain abnormal neuronal elements such as balloon cells. Advances in neuroimaging have allowed better identification of these lesions, and thus more patients have become surgical candidates.
Focal dermal hypoplasia (FDH) is an uncommon genetic disorder characterized by distinctive skin abnormalities and a wide variety of defects that affect the eyes; teeth; and skeletal, urinary, gastrointestinal, cardiovascular, and central nervous systems. It is usually, but not always, X-linked dominant (lethal in males). The mnemonic FOCAL can be used to remember some of the key features of this syndrome: female sex; osteopathia striata; coloboma; absent ectodermis-, mesodermis-, and neurodermis-derived elements; and lobster claw deformity. FDH is also known as Goltz syndrome or Goltz-Gorlin syndrome.
Focal dystonia is a muscle/movement disorder that causes spasms and uncontrollable muscle contractions in a localized area of the body. It typically affects the hand and/or arm; eyes; vocal cords; mouth and/or jaw; and neck.
source: eHow
Focal facial dermal dysplasia (medical condition): A rare inherited disorder characterized by scar-like depressions on the temples..Setleis syndrome is an extremely rare inherited disorder that belongs to a group of diseases known as ectodermal dysplasias. Ectodermal dysplasias typically affect the hair, teeth, nails, and/or skin. Setleis syndrome is characterized by distinctive abnormalities of the facial area that may be apparent at birth (congenital). Most affected infants have multiple, scar-like, circular depressions on both temples (bitemporal). These marks closely resemble those made when forceps are used to assist delivery. In addition, affected infants may have puffy, wrinkled skin around the eyes (periorbital) and/or abnormalities of the eyelashes, eyebrows, and eyelids. Infants with Setleis syndrome may be missing eyelashes on both the upper and lower lids, or they may have multiple rows of lashes on the upper lids but none on the lower lids. In addition, in some cases, the bridge of the nose may appear flat, while the tip may appear unusually rounded (bulbous).
(also, and better, called cortical developmental anomaly), term referring to a wide spectrum of developmental malformations of the cortex caused by disruption to its normal process of formation, which includes proliferation, migration and organization (lamination, giration and sulcation)
Focal segmental glomerulosclerosis (FSGS) is a cause of nephrotic syndrome in children and adolescents, as well as a leading cause of kidney failure in adults. It is also known as "focal glomerular sclerosis" or "focal nodular glomerulosclerosis." It accounts for about a sixth of the cases of nephrotic syndrome. (Minimal change disease (MCD) is by far the most common cause of nephrotic syndrome in children: MCD and primary FSGS may have a similar cause.)
Foix-Chavany-Marie syndrome, also known as bilateral anterior opercular syndrome is a partial paralysis of the face, pharynx and jaw caused by a loss of blood supply in a specific region of the brain. It was described in 1926 by Charles Foix, Jean Alfred Émile Chavany and Julien Marie in the Revue Neurologique
Follicle-stimulating hormone deficiency, isolated: A genetic disorder characterized by the deficiency of follicle-stimulating hormone which primarily affects fertility.
Follicular dendritic cell tumor: A rare form of malignant tumor. Follicular dendritic cells are immune system cells found in lymph follicles. The tumor tends to be low grade and tends to reoccur after removal and occasionally metastasizes. The symptoms are determined by the location and size of the tumor. The tumor can occur on various parts of the body such as lymph nodes, tonsils, armpits and mediastinum but is most common in the neck lymph nodes.
Follicular hamartoma - alopecia - cystic fibrosis: A rare syndrome characterized by small benign growths that develop in hair follicles, alopecia and cystic fibrosis
Follicular ichthyosis: A genetic skin disorder which causes the skin to become red, dry and scaly. It can occur anywhere on the body where there are hair follicles.
Follicular lymphoma (FL) is the most common of non-Hodgkin’s lymphomas accounting for approximately 20 percent to 30 percent of all non-Hodgkin’s lymphoma. It is defined as a lymphoma of follicle center B-cells (centrocytes and centroblasts), which has at least a partially follicular pattern. It is positive for the B-cell markers CD10, CD19, CD22, and usually CD20, but almost always negative for CD5. It is called ‘follicular’ lymphoma because the abnormal lymphocytes often collect in lymph nodes in clumps that are known as ‘follicles’.
Common signs of disease include enlargement of the lymph nodes in the neck, underarm, stomach, or groin, as well as fatigue, shortness of breath, night sweats, and weight loss. Often, people with FL have no obvious symptoms of the disease at diagnosis.
Over time, some patients with FL may eventually develop a transformed lymphoma, which is often more aggressive and usually requires more intensive types of treatment.
Follicular lymphoreticuloma (medical condition): A rare disorder characterized by a localized overgrowth of lymph node tissue which can form a benign tumor-like growth. There are two types of the disease: hyaline-vascular type or the plasma cell type which tends to have more severe symptoms. The plasma-cell type tends to involve systemic symptoms such as fever and weight loss due to the destruction of red blood cells
Fontaine-Farriaux-Blanckaert syndrome: A rare syndrome characterized by premature fusion of skull bones as well as various other abnormalities.
Food Protein-Induced Enterocolitis Syndrome (FPIES) is a severe systemic response to food protein that typically occurs 1 to 4 hours after the ingestion of the causative food and frequently develops in the first few years of life. In the severe form, patients will vomit until dehydration and until a shock-like state, which occurs in 15% of patients. FPIES occurs primarily in young infants, but can exist in older children and adults.
Forbes-Albright syndrome: A rare condition where a hormone secreting pituitary or hypothalamic tumor causes galactorrhea and amenorrhea.
Foreign accent syndrome (FAS) is a rare and acquired speech disorder. In many cases, it is caused by a Stroke. Damage to the brain affects the rhythm and melody of speech. If you have FAS, you adopt what sounds like a foreign accent, even though you may never have traveled to that particular country.
Forestier disease: A form of degenerative arthritis characteristically associated with flowing calcification along the sides of the vertebrae of the spine and commonly with inflammation (tendinitis) and calcification of the tendons at their attachments points to bone
Formaldehyde is a nearly colorless gas with a pungent, irritating odor even at very low concentrations (below 1 ppm). Its vapors are flammable and explosive. Because the pure gas tends to polymerize, it is commonly used and stored in solution. Formalin, the aqueous solution of formaldehyde (30% to 50% formaldehyde), typically contains up to 15% methanol as a stabilizer.
Forney Robinson Pascoe syndrome: A rare condition characterized by skeletal abnormalities, deafness and mitral regurgitation.
Fountain Syndrome: A very rare inherited disorder involving mental retardation, sensorineural deafness, skeletal defects, coarse facial features and full lips.
Fowler-Christmas-Chapple syndrome: A rare syndrome characterized by the association of polycystic ovaries with the abnormal functioning of the urinary valve.
Fox-Fordyce disease is a rare skin disorder that occurs mainly in women between the ages of 13 and 35 years. However, it sometimes affects males and children. The condition is also referred to as ‘apocrine duct occlusion’ and ‘sweat retention disease’. The condition is characterised by the development of itchy bumps around the hair follicles of the underarm area, pubic region, and/or around the nipples. It results from inflammation of the aprocrine sweat glands, which are found only in these areas.
FOXG1 syndrome is a condition characterized by impaired development and structural brain abnormalities. Affected infants are small at birth, and their heads grow more slowly than normal, leading to an unusually small head size (microcephaly) by early childhood. The condition is associated with a particular pattern of brain malformations that includes a thin or underdeveloped connection between the right and left halves of the brain (a structure called the corpus callosum), reduced folds and grooves (gyri) on the surface of the brain, and a smaller than usual amount of brain tissue known as white matter.
FOXG1 syndrome was previously described as a congenital variant of Rett syndrome, which is a similar disorder of brain development. Both disorders are characterized by impaired development, intellectual disability, and problems with communication and language. However, Rett syndrome is diagnosed almost exclusively in females, while FOXG1 syndrome affects both males and females. Rett syndrome also involves a period of apparently normal early development that does not occur in FOXG1 syndrome. Because of these differences, physicians and researchers now usually consider FOXG1 syndrome to be distinct from Rett syndrome.
Fragile X syndrome, or Martin-Bell syndrome, is a genetic syndrome which results in a spectrum of characteristic physical, intellectual, emotional and behavioural features which range from severe to mild in manifestation. Fragile X syndrome (also called FXS) is the most common cause of inherited mental retardation. It is also the most common known cause of autism. It affects about 1 in 4000 males and 1 in 8000 females.
There are four generally accepted forms of Fragile X syndrome which relate to the length of the repeated CGG sequence:
Normal (29-31 CGG repeats), Premutation (55-200 CGG repeats), Full Mutation (more than 200 CGG repeats), and Intermediate or Gray Zone Alleles (40 - 60 repeats).