The most common presentation of Milroy Disease is bilateral lower extremity lymphedema, and may also be accompanied by hydrocele.

Milroy's disease (MD) is a familial disease characterized by lymphedema, commonly in the legs, caused by congenital abnormalities in the lymphatic system. Disruption of the normal drainage of lymph leads to fluid accumulation and hypertrophy of soft tissues. It is also known as Milroy disease, Nonne-Milroy-Meige syndrome and hereditary lymphedema.

It was named by Sir William Osler for William Milroy, a Canadian physician, who described a case in 1892, though it was first described by Rudolf Virchow in 1863.

Differential diagnoses can be:

- Todd's paresis

- Stroke

- Systemic lupus erythematosus

- Metabolic disorders

- Inherited disorders such as mitochondrial myopathy

MRI features can be suggestive of cortical hyper intensity and edema.

Café au lait spots are usually present at birth, permanent, and may grow in size or increase in number over time.

Cafe au lait spots are themselves benign and do not cause any illness or problems. However, they may be associated with syndromes such as Neurofibromatosis Type 1 and McCune-Albright syndrome.

The size and shape of the spots do not have any meaning or implications with regards to diagnosis of associated syndromes.

Diagnosis is visual with measurement of spot size. The number of spots can have clinical significance for diagnosis of associated disorders such as Neurofibromatosis type I. Greater than or equal to 6 spots of at least 5mm in diameter in pre-pubertal children and at least 15mm in post-pubertal individuals is one of the major diagnostic criteria for NF1.

Polyps are most frequent in the stomach and large intestine, are also found in the small intestine, and are least frequent in the esophagus. A biopsy will reveal them to be hamartomas; the possibility that they progress to cancer is generally considered to be low, although it has been reported multiple times in the past. Chronic diarrhea and protein-losing enteropathy are often observed. Possible collateral features include variable anomalies of ectodermal tissues, such as alopecia, atrophy of the nails, or skin pigmentation

Prepubertal hypertrichosis is a cutaneous condition characterized by increased hair growth, and is a relatively common finding in otherwise healthy infants and children, most often occurring in individuals of Mediterranean or South Asian descent.

Typically, episodic ataxia presents as bouts of ataxia induced by startle, stress, or exertion. Some patients also have continuous tremors of various motor groups, known as myokymia. Other patients have nystagmus, vertigo, tinnitus, diplopia or seizures.

Acquired generalized lipodystrophy (also known as "Lawrence syndrome," and "Lawrence–Seip syndrome", abbreviation: AGL) is a rare skin condition that appears during childhood or adolescence, characterized by fat loss affecting large areas of the body, particularly the face, arms, and legs. There are 4 types of lipodystrophy based on its onset and areas affected: acquired or inherited (congenital or familial), and generalized or partial. Both acquired or inherited lipodystrophy present as loss of adipose tissues. The near-total loss of subcutaneous adipose tissue is termed generalized lipodystrophy while the selective loss of adipose tissues is denoted as partial lipodystrophy. Thus, as the name suggests, AGL is a near-total deficiency of adipose tissues in the body that is developed later in life. It is an extremely rare disease that only about 100 cases are reported worldwide. There are three main etiologies of AGL suspected: autoimmune, panniculitis-associated, or idiopathic. After its onset, the disease progresses over a few days, weeks, months, or even in years. Clinical presentations of AGL are similar to other lipodystrophies, including metabolic complications and hypoleptinemia. Treatments are also similar and mainly supportive for symptomatic alleviation. Although HIV- or drug-induced lipodystrophy are a type of acquired lipodystrophy, its origin is very specific and distinct hence is usually not discussed with AGL (see HIV-Associated Lipodystrophy).

Cronkhite–Canada syndrome is a rare syndrome characterized by multiple polyps of the digestive tract. It is sporadic (i.e. it does not seem to be a hereditary disease), and it is currently considered acquired and idiopathic (i.e. cause remains unknown).

About two-thirds of patients are of Japanese descent and the male to female ratio is 2:1. It was characterized in 1955.

There is no known cause for this disease; however, three origins of AGL are generally suspected: panniculitis-associated, autoimmune-associated, and idiopathic AGLs. Triggers may include infections that aggravate the panniculitis, or any disease state that can induce autoimmunity. Overlap between panniculitis and autoimmune types also exists. Another theory suggest that AGL is an autoimmune disease itself, as panniculitis can be described as an autoimmune disease, however its triggering factors remains to be unknown. Underlying genetic factor may be associated; however neither confirmed nor rejected.

Episodic ataxia type-3 (EA3) is similar to EA1 but often also presents with tinnitus and vertigo. Patients typically present with bouts of ataxia lasting less than 30 minutes and occurring once or twice daily. During attacks, they also have vertigo, nausea, vomiting, tinnitus and diplopia. These attacks are sometimes accompanied by headaches and precipitated by stress, fatigue, movement and arousal after sleep. Attacks generally begin in early childhood and last throughout the patients' lifetime. Acetazolamide administration has proved successful in some patients. As EA3 is extremely rare, there is currently no known causative gene. The locus for this disorder has been mapped to the long arm of chromosome 1 (1q42).

List of common symptoms:

- "sac-like" appearance of the vocal folds

- Hoarseness and deepening of the voice

- Trouble speaking (Dysphonia)

- Reduced vocal range with diminished upper limits

- Stretching of the mucosa (Distension)

- Shortness of breath

Reinke's edema is characterized by a "sac-like" appearance of the vocal folds. The edema is a white translucent fluid that causes a bulging (distension) of the vocal cord. The most common clinical symptom associated with Reinke's edema is an abnormally low pitched voice with hoarseness. The low pitch voice is a direct result of increased fluid in the Reinke's space, which vibrates at a lower frequency than normal (females <130 Hz; males <110 Hz). Hoarseness is a common problem of many laryngeal diseases, such as laryngitis. It is described as a harsh and breathy tone of voice. Hoarseness is often seen alongside dysphonia, a condition in which the individual has difficulty speaking.

The swelling of the vocal cords and the lowering of the voice are warning signs that an individual has Reinke's edema. At the microscopic level, an examination of the vocal cords in patients with Reinke's edema will show lowered levels of collagen, elastin, and extracellular matrix proteins. These characteristics can be used to diagnose Reinke's edema. Reinke's edema is considered a benign polyp that may become precancerous if smoking is involved. An indicator of cancer is the development of leukoplakia, which manifests as white patches on the vocal folds.

Smoking, gastric reflux, and hypothyroidism are all risk factors for Reinke's edema. The symptoms of Reinke's edema are considered to be chronic symptoms because they develop gradually over time and depend on how long the individual is exposed to the risk factor. In the case of smoking, as long as the individual continues the habit of smoking, the Reinke's edema will continue to progress. This is true for other risk factors as well, such as untreated gastric reflux and overuse of the voice, which is common to professions such as singers and radio announcers.

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.)

Benign familial infantile epilepsy (BFIE), also known as benign familial infantile seizures (BFIS) or benign familial infantile convulsions (BFIC) is an epilepsy syndrome. Affected children, who have no other health or developmental problems, develop seizures during infancy. These seizures have focal origin within the brain but may then spread to become generalised seizures. The seizures may occur several times a day, often grouped in clusters over one to three days followed by a gap of one to three months. Treatment with anticonvulsant drugs is not necessary but they are often prescribed and are effective at controlling the seizures. This form of epilepsy resolves after one or two years, and appears to be completely benign. The EEG of these children, between seizures, is normal. The brain appears normal on MRI scan.

A family history of epilepsy in infancy distinguishes this syndrome from the non-familial classification (see benign infantile epilepsy), though the latter may be simply sporadic cases of the same genetic mutations. The condition is inherited with an autosomal dominant transmission. There are several genes responsible for this syndrome, on chromosomes 2, 16 and 19. It is generally described as idiopathic, meaning that no other neurological condition is associated with it or causes it. However, there are some forms that are linked to neurological conditions. One variant known as infantile convulsions and choreoathetosis (ICCA) forms an association between BFIE and paroxysmal kinesigenic choreoathetosis and has been linked to the PRRT2 gene on chromosome 16. An association with some forms of familial hemiplegic migraine (FHM) has also been found. Benign familial infantile epilepsy is not genetically related to benign familial neonatal epilepsy (BFNE), which occurs in neonates. However, a variation with seizure onset between two days and seven months called "benign familial neonatal–infantile seizures" (BFNIS) has been described, which is due to a mutation in the SCN2A gene.

Peeling skin syndrome (also known as "Acral peeling skin syndrome," "Continual peeling skin syndrome," "Familial continual skin peeling," "Idiopathic deciduous skin," and "Keratolysis exfoliativa congenita") is an autosomal recessive disorder characterized by lifelong peeling of the stratum corneum, and may be associated with pruritus, short stature, and easily removed anagen hair.

The acral form can be associated with "TGM5".

Micromastia can be congenital or disorder and may be unilateral or bilateral. Congenital causes include ulnar–mammary syndrome (caused by mutations in the TBX3 gene), Poland syndrome, Turner syndrome, and congenital adrenal hyperplasia. There is also a case report of familial hypoplasia of the nipples and athelia associated with mammary hypoplasia that was described in a father and his daughters. Acquired causes of micromastia include irradiation in infancy and childhood and surgical removal of prepubertal breast bud.

HP is characterised by attacks of epigastric pain, which are often associated with nausea and vomiting. Symptoms may start shortly after birth but onset varies periodically, with some patients not exhibiting symptoms until adulthood. There is usually progression to chronic pancreatitis with endocrine and exocrine failure and a mortally increased risk of pancreatic cancer. Lifetime risk of cancer has been variously calculated as 35–54% to the age of 75 years and screening for early pancreatic cancer is being offered to HP sufferers on a scientific basis. Some patients may choose to have their pancreas surgically removed to prevent pancreatic cancer from developing in the future.

The epidemiology of HP follows a similar pattern to alcohol-associated chronic pancreatitis, but there are important differences. For example, HP typically has an earlier age of pancreatitis onset; although malabsorption and diabetes mellitus occur at a later stage in the disease progression.

Reinke's edema is the swelling of the vocal cords due to fluid (edema) collected within the Reinke's space. First identified by the German anatomist Friedrich B. Reinke in 1895, the Reinke's space is a gelatinous layer of the vocal cord located underneath the outer cells of the vocal cord. When a person speaks, the Reinke's space vibrates to allow for sound to be produced (phonation). The Reinke's space is sometimes referred to as the superficial lamina propria.

Reinke's edema is characterized by the "sac-like" appearance of the fluid-filled vocal cords. The swelling of the vocal folds causes the voice to become deep and hoarse. Therefore, the major symptom of Reinke's edema is a hoarseness similar to laryngitis. The major cause associated with Reinke's edema is smoking. In fact, 97% of patient's diagnosed with Reinke's edema are habitual smokers. Other identified risk factors include overuse of the vocal cords, gastroesophageal reflux, and hypothyroidism. The disease is more often cited in women than in men, because lower voice changes are more noticeable in women.

The first cases of Reinke's edema were recorded in 1891 by M. Hajek, followed by F. Reinke in 1895. In his investigations, Reinke injected a stained glue into the superficial lamina propria (Reinke's space) to mimic edema. Reinke's edema is considered to be a benign (non-cancercous) polyp (protrusion) that represents 10% of all benign laryngeal pathologies. Treatment of Reinke’s edema starts with the elimination of associated risk factors, such as smoking, gastric reflux, and hypothyroidism. Advanced cases may undergo phonosurgery to remove the fluid from the vocal cords.

Depending on the cause it is broadly classified as:

- Primary, when no underlying cause is found; usually presents as nephrotic syndrome

- Secondary, when an underlying cause is identified; usually presents with kidney failure and proteinuria. This is actually a heterogeneous group including numerous causes such as

- Toxins and drugs such as heroin and pamidronate

- Familial forms

- Secondary to nephron loss and hyperfiltration, such as with chronic pyelonephritis and reflux, morbid obesity, diabetes mellitus

There are many other classification schemes also.

Progressive myoclonus epilepsy (PME) is a rare epilepsy syndrome caused by a variety of genetic disorders. The syndrome includes myoclonic seizures and tonic-clonic seizures together with progressive neurological decline.

In the early stages, it can be difficult to distinguish progressive myoclonic epilepsy from benign idiopathic generalised epilepsies, such as juvenile myoclonic epilepsy. With PME, the initial effectiveness of anticonvulsant treatment diminishes as seizures become more frequent and neurological decline progresses. However, these can also be signs of anticonvulsant intoxication. The myoclonus in PME is usually severe and is the prominent seizure type.

Dermatochalasis is sometimes confused with blepharochalasis, but these are two different conditions.

Hereditary pancreatitis (HP) is an inflammation of the pancreas, attributed to genetic causes. It was first described in 1952 by Comfort and Steinberg but it was not until 1996 that Whitcomb "et al" isolated the first responsible mutation in the trypsinogen gene ("PRSS1") on the long arm of chromosome seven ("7q35").

The term "hereditary pancreatitis" is used when a genetic biomarker is identified, and "familial pancreatitis" otherwise.