Diagnosis is made based on features as well as by the very early onset of serious eye and ear disease. Because Marshall syndrome is an autosomal dominant hereditary disease, physicians can also note the characteristic appearance of the biological parent of the child. There are no tests for Stickler syndrome or Marshall syndrome. Some families with Stickler syndrome have been shown to have mutations in the Type II collagen gene on chromosome 1. However, other families do not show the linkage to the collagen gene. It is an area of active research, also the genetic testing being expensive supports that the diagnosis is made depending on the features.

Suspicion of a chromosome abnormality is typically raised due to the presence of developmental delays or congenital malformations. Diagnosis of tetrasomy 18p is typically made via a routine chromosome analysis from a blood sample. The diagnosis can also be made prenatally by chorionic villus sampling or amniocentesis.

Severity of tetrasomy 18p is variable. Individuals with mosaicism are typically less severely affected than non-mosaic individuals.

There is no medical treatment for either syndrome but there are some recommendations that can help with prevention or early identification of some of the problems. Children with either syndrome should have their hearing tested, and adults should be aware that the hearing loss may not develop until the adult years. Yearly visits to an ophthalmologist or other eye care professional who has been informed of the diagnosis of Stickler or Marshall syndrome is important for all affected individuals. Children should have the opportunity to have myopia corrected as early as possible, and treatment for cataracts or detached retinas may be more effective with early identification. Support for the joints is especially important during sports, and some recommend that contact sports should be avoided by those who have very loose joints.

Current research is focusing on clearly defining the phenotype associated with tetrasomy 18p and identifying which genes cause medical and developmental problems when present in four copies.

Stiff skin syndrome (also known as "Congenital fascial dystrophy") is a cutaneous condition characterized by ‘rock hard’ induration, thickening of the skin and subcutaneous tissues, limited joint mobility, and mild hypertrichosis in infancy or early childhood. Immunologic abnormalities or vascular hyperactivity are not present in patients.

Not much is known about it, cause or treatment, as it has only been reported 41 times throughout history. Not much is known about this, and further investigation is required.According to news reports on one particular patient by name of Jaiden Rogers, the patient's skin hardens in some places, and it slowly spreads over the surrounding area. For Rogers, it's spreading over the back, legs, and hips, inhibiting his ability to walk. He say it hurts, but finds it difficult to describe the sensations further. Currently, it appears that chemotherapy similar to that used for cancer is slowing the spread, but it also appears that once the skin has hardened it cannot revert to its healthy flexible state. Physical therapy also appears to help. Further investigation is required.

Diagnosis can be difficult as symptoms may be nonspecific. A CT scan of the head is typically recommended if a concern is present. While retinal bleeding is common, it can also occur in other conditions.

Say syndrome is a condition characterized by bilateral acromial dimples.

While the findings of AHT are complex and many, they are often referred to as a "triad". The process of inferring violent or abusive shaking from the findings in the SBS diagnosis has also been referred to as a hypothesis.

In 2000, Rob Parish, Deputy Director of the National Center on Shaken Baby Syndrome, summarized the "triad" as follows: "Often referred to as the “triad”, the consensus continues to be that a collection of (1)damage to the brain, evidenced by severe brain swelling and/or diffuse traumatic axonal injury; (2) bleeding under the membranes which cover the brain, usually subdural and/or subarachnoid bleeding; and, (3) bleeding in the layers of the retina, often accompanied by other ocular damage, when seen in young children or infants, is virtually diagnostic of severe, whiplash shaking of the head."

SBS may be misdiagnosed, underdiagnosed, and overdiagnosed, and caregivers may lie or be unaware of the mechanism of injury. Commonly, there are no externally visible signs of the condition. Examination by an experienced ophthalmologist is often critical in diagnosing shaken baby syndrome, as particular forms of ocular bleeding are quite characteristic. Magnetic resonance imaging may also depict retinal bleeds; this may occasionally be useful if an ophthalmologist examination is delayed or unavailable. Conditions that must be ruled out include hydrocephalus, sudden infant death syndrome (SIDS), seizure disorders, and infectious or congenital diseases like meningitis and metabolic disorders. CT scanning and magnetic resonance imaging are used to diagnose the condition. Conditions that may accompany SBS include bone fractures, injury to the cervical spine (in the neck), retinal bleeding, cerebral bleed or atrophy, hydrocephalus, and papilledema (swelling of the optic disc).

The terms "non-accidental head injury" or "inflicted traumatic brain injury" have been suggested instead of "SBS".

The connection of the triad to episodes of traumatic shaking is controversial with a 2016 systematic review finding limited scientific evidence associating the triad to episodes of traumatic shaking, and insufficient evidence for using the triad to identify such episodes. The connection is controversial in part following cases where parents of children exhibiting the triad have, in addition to losing custody, been jailed or sentenced to death.

Neuralgia-inducing cavitational osteonecrosis (NICO) is a controversial diagnosis whereby a putative jawbone cavitation causes chronic facial neuralgia; this is different from osteonecrosis of the jaw.. In NICO the pain is said to result from the degenerating nerve ("neuralagia"). The condition is probably rare, if it does exist.

Also called Ratner's bone cavity, a neuralgia-inducing cavitational osteonecrosis was first described in dental literature by G V Black in 1920. Several decades later, oral pathologist Jerry E Bouquot took especial interest in NICO.

The diagnostic criteria for NICO are imprecise, and the research offered to support it is flawed. The diagnosis is popular among holistic dentists who attempt to treat NICO by surgically removing the dead bone they say is causing the pain.

It has been rejected as quackery by some dentists and maxillofacial surgeons. In its position statement, dated 1996, the American Association of Endodontists asserted that although NICO occur and are treatable in toothless areas, NICO occurrence and treatment at endodontically treated teeth is generally implausible, that the diagnosis ought to be a last resort, and that routine extraction of endodontically treated teeth is misguided.

Via a photo shown on a Facebook page, the mother of a child previously diagnosed with this condition recognised the symptoms and reported them to the family involved, resulting in an immediate diagnosis that medical professionals had overlooked in all earlier consultations.

Pustulosis palmaris et plantaris (also known as pustulosis of palms and soles, palmoplantar pustulosis, persistent palmoplantar pustulosis, pustular psoriasis of the Barber type, and pustular psoriasis of the extremities) is a chronic recurrent pustular dermatosis (that is, a pustulosis or pustular psoriasis) localized on the palms and soles only, characterized histologically by intraepidermal pustules filled with neutrophils. It can occur as part of the SAPHO syndrome.

Diagnosis can be characterized by typical facial and cranial deformities.

Observatory signs of trigonocephaly are:

- a triangular shaped forehead seen from top view leading to a smaller anterior cranial fossa

- a visible and palpable midline ridge

- hypotelorism inducing ethmoidal hypoplasia

Imaging techniques (3D-CT, Röntgenography, MRI) show:

- epicanthal folds in limited cases

- teardrop shaped orbits angulated towards the midline of the forehead ('surprised coon' sign) in severe cases

- a contrast difference between a röntgenograph of a normal and a trigonocephalic skull

- anterior curving of the metopic suture seen from lateral view of the cranium on a röntgenograph

- a normal cephalic index (maximum cranium width / maximum cranium length) however, there is bitemporal shortening and biparietal broadening

The neuropsychological development is not always affected. These effects are only visible in a small percentage of children with trigonocephaly or other suture synostoses. Neuropsychological signs are:

- problems in behaviour, speech and language

- mental retardation

- neurodevelopmental delays such as ADHD (Attention Deficit Hyperactivity Disorder), ODD (Oppositional Defiant Disorder), ASD (Autism Spectrum Disorder) and CD (Conduct Disorder). Many of these delays become evident at school age.

To treat the trigonocephaly, expanding the distance between orbits using springs seems to work. It allows enough space for the brain to grow and it creates a normal horizontal axis of the orbits and supraorbital bar. The endoscopic surgery started to become popular since the early 90's, but it has some technical limitations (only strip cranictomy is possible). There have been few attempts to go beyond the limits.

Aesthetic outcomes of metopic surgery have been good. Surgery does not have a perfect outcome because there will most likely be minor irregularities. Sometimes reoperations are needed for the severe cases. Trying to hollow out the temporal, and the hypoterlorism are very hard to correct. The hypotelorism usually stays not corrected and in order to correct the temporal hollowing, a second operation is most likely needed.

Three main points in diagnosing thumb hypoplasia are: width of the first web space, instability of the involved joints and function of the thumb. Thorough physical examination together with anatomic verification at operation reveals all the anomalies. An X-ray of the hand and thumb in two directions is always mandatory. When the pediatrician thinks the condition is associated with some kind of syndrome other tests will be done. More subtle manifestations of types I and II may not be recognized, especially when more obvious manifestations of longitudinal radial deficiency in the opposite extremity are present. Therefore, a careful examination of both hands is important.

The preferable way to diagnose the presence of this syndrome would be to use the help of clinical tests and medical reports after the tests and examinations. Now being aware of the subject that HAIR-AN syndrome is caused by genetic, environmental factors and also the hyperandogenism, insulin resistance and acanthosis nigricans, some of the way we could diagnosis this syndrome is by looking for signs in the body for symptoms leading to relate to those key contributors discussed above.

According to studies HAIR-AN is to be found in 1% to 3% women possessing hyperandrogenism. It is an established concept in physiopathology that the androgen in the female body is produced by the stromal ovarian cells, when stimulated by the LH and HCG. The observed activity of these cells was elevated by insulin, and later was found to be used as a determining element to find how severe the hirsutism was. Physicians must look for obesity, as it is also a diagnostic factor in many possible cases.

When it comes to treatment it is important to differentiate a thumb that needs stability, more web width and function, or a thumb that needs to be replaced by the index finger. Severe thumb hypoplasia is best treated by pollicization of the index finger. Less severe thumb hypoplasia can be reconstructed by first web space release, ligament reconstruction and muscle or tendon transfer.

It has been recommended that pollicization is performed before 12 months, but a long-term study of pollicizations performed between the age of 9 months and 16 years showed no differences in function related to age at operation.

It is important to know that every reconstruction of the thumb never gives a normal thumb, because there is always a decline of function. When a child has a good index finger, wrist and fore-arm the maximum strength of the thumb will be 50% after surgery in comparison with a normal thumb. The less developed the index finger, wrist and fore-arm is, the less strength the reconstructed thumb will have after surgery.

The following are some of the common symptoms of RHS:

- Depression

- Skin rash

- Asthma

- Ulcers

- High blood pressure

In response to a WHO call for papers at the 5th Paris Appeal Congress of Environmental Idiopathic Intolerance conference that took place in Belgium on the 18th of May, a report that was generally supportive quoted a number of international practitioners. This was provisionally accepted by the Spanish health ministry, and later found proven by a judge in the case of a plumber in the Province of Castellón

MCS is a diagnosis of exclusion, and the first step in diagnosing a potential MCS sufferer is to identify and treat all other conditions which are present and which often explain the reported symptoms. For example, depression, allergy, thyroid disorders, orthostatic syndromes, lupus, hypercalcemia, and anxiety need to be carefully evaluated and, if present, properly treated. The "gold standard" procedure for identifying a person who has MCS is to test response to the random introduction of chemicals the patient has self-identified as relevant. This may be done in a carefully designed challenge booth to eliminate the possibility of contaminants in the room. Chemicals and controls, sometimes called prompts, are introduced in a random method, usually scent-masked. The test subject does not know when a prompt is being given. Objective and subjective responses are measured. Objective measures, such as the galvanic skin response indicate psychological arousal, such as fear, anxiety, or anger. Subjective responses include patient self-reports. A diagnosis of MCS can only be justified when the subject cannot consciously distinguish between chemicals and controls, and when responses are consistently present with exposure to chemicals and consistently absent when prompted by a control.

A 1999 consensus statement recommends that MCS be diagnosed according to six standardized criteria:

1. Symptoms are reproducible with repeated (chemical) exposures

2. The condition has persisted for a significant period of time

3. Low levels of exposure (lower than previously or commonly tolerated) result in manifestations of the syndrome ("i.e." increased sensitivity)

4. The symptoms improve or resolve completely when the triggering chemicals are removed

5. Responses often occur to multiple chemically unrelated substances

6. Symptoms involve multiple-organ symptoms (runny nose, itchy eyes, headache, scratchy throat, ear ache, scalp pain, mental confusion or sleepiness, palpitations of the heart, upset stomach, nausea and/or diarrhea, abdominal cramping, aching joints).

Say–Neger syndrome is a rare X-linked genetic disorder that is mostly characterized as developmental delay. It is one of the rare causes of short stature. It is closely related with trigonocephaly (a misshapen forehead due to premature fusion of bones in the skull). People with Say–Meyer syndrome have impaired growth, deficits in motor skills development and mental state.

It is suggested that it is from a X-linked transmission.

The International Statistical Classification of Diseases and Related Health Problems (ICD), maintained by the World Health Organization, does not recognize multiple chemical sensitivity or environmental sensitivity as a valid diagnosis. The Australian Department of Health recognizes that sometimes debilitating symptoms are attributed to MCS but notes that diagnosis, treatment, and any underlying mechanism remain uncertain. The German Institute for Medical Documentation and Information recognizes MCS as a physical disease and is subsequentially recognized in Austria. The American Medical Association does not recognize MCS as an organic disease because of the lack of scientific evidence supporting a cause-and-effect relationship between very low level exposure and the symptoms of MCS. The American Academy of Allergy, Asthma, and Immunology, the California Medical Association, the American College of Physicians, and the International Society of Regulatory Toxicology and Pharmacology also do not recognize MCS. The US Occupational Safety and Health Administration (OSHA) indicates that MCS is highly controversial and that there is insufficient scientific evidence to explain the relationship between the suggested causes of MCS and its symptoms. OSHA recommends evaluation by a physician knowledgeable of the symptoms presented.

Hospitalization may be necessary during the acute phase of symptoms, and psychiatric care if the patient is a danger to self or others. A neurological consult is advised to rule out any organic cause.

HAIR-AN syndrome as discussed earlier is caused by both gentic and environmental factors. It is found out that women affected by this syndrome or PCOS (polycystic ovary syndrome) are generally accompanied by obesity. Weight loss is most suggested way to combat this syndrome and is helpful for reducing insulin resistance of the body. It is also a good way to have a control on diet. This might help the body to refunction properly and show some resistance to HAIR-AN syndrome. "Suppression of gonadotropin with estrogen-progesterone oral contraceptives" or can say as reducing hyperandrogenism by the use of estoprogestatif can reduce production of androgen by ovaries by cutting down the LH (leutinizing hormone) level in body. Even their sex hormone binding to globulin increase is also responsible for decreasing body's bio-availability of testosterone. There are also few pills of new progestins, such as desogestrel and norgestimate. This pills appear to have fewer androgenic side effects and may be safer to use in persons with abnormal lipid levels or hirsutism. Some antiandrogenic agents can be also used alone or combining it with other oral pills.

"Spironolactone inhibit the actions of testosterone by binding to its receptors." The standard dose for its use is considered to be 50 to 100 mg twice a day. This might lead to irregular menstrual bleeding, which can be improved by oral contraceptives. Flutamide, an another antiandorgen that is used to treat HAIR-AN syndrome, but it has risk of hepatotoxicity. Finasteride is a 5α-reductase inhibitor which can reduces the conversion of testosterone to dihydrotestosterone. It is useful in the treatment of hirsutism with a dosages as low as 5 mg per day.

Insulin-resistant patients can also be treated with metformin which has shown promising results to reduce the insulin resistivity. Metformin improves peripheral tissue sensitivity to insulin but inhibits hepatic glucose formation. The drug reduces the levels of circulating insulin and androgens. Women have shown improved reproductive functioning after the use of metformin.

Aposthia is a rare congenital condition in humans, in which the foreskin of the penis is missing.

Toward the end of the nineteenth century, E. S. Talbot claimed that aposthia among Jews was evidence for the now-discredited Lamarckian theory of evolution. In his work, ""The Variation of Animals and Plants under Domestication"", Charles Darwin also mentioned cases of "born circumcised" babies as "conclusive evidence" for the now-discredited blending inheritance.

It is likely that the cases he described were actually hypospadias, a condition in which the urinary meatus is on the underside of the penis. Neither condition has been shown to have a higher frequency in Jews or Muslims.

This syndrome was identified and coined by Nobuo Kurokawa and first appeared in a presentation of his to the Japanese Society of Psychosomatic Medicine in 1991. It is a condition where a woman begins to exhibit signs of physical illness and depression as her husband reaches, or approaches, retirement.

Kurokawa has theorized that RHS is a result of the fact that many of Japan's citizens who are reaching retirement age, 60, are members of the Baby Boomer generation of Japan. The members of this generation were expected to meet certain social requirements: that the man should be the breadwinner and work to support his family, and the woman was to be not only a homemaker but also to show a level of adoration for her salaryman husband as reward for his bringing in the money she used to look after their children and socialize with her friends.

As the husband's career as a salaryman can demand long hours away from home, both working and socializing with other salarymen and their bosses as is expected, a husband may leave home in the early hours of the morning and return home late at night. This could mean that a husband and wife may not interact extensively and when a husband retires both members of the couple can feel they are living together with someone who is a virtual stranger.

This can be a particularly stressful experience for the woman who, as society dictated in her youth, is expected to attend to her husband's every need and can find this a very large demand indeed. The stress this change in life style brings can lead not only to the above listed symptoms, but also to a level of resentment felt toward her husband. Some couples have been known to separate over RHS, however divorce is uncommon as it is not considered an acceptable option for that generation of Japanese. Also currently an ex-wife has no rights to a portion of her husband's pension should they divorce, and therefore may be unable to survive financially (though this was set to change in 2007). Despite this, the divorce rate among older Japanese couples has soared in recent decades, as more of the baby boomer population have retired, increasing by 26.5% in 10 years according to the health ministry. The number of divorces among couples married for 20 years or more hit 42,000 in 2004, double those recorded in 1985. Divorces among those married for more than 30 years quadrupled during the same period. In 2006, these figures were projected to rise further as more Japanese people were expected to retire in the subsequent five years than at any other point in Japanese history.

Some women deal with RHS by focusing their energy on obsessions such as collecting teddy bears, or following a celebrity, which they say can help them psychologically. They may also ask their husbands to stay on at work past retirement age. Many wives do not tell their husbands what is happening and this can worsen the stress as their husbands may not understand or even realize their wives are RHS sufferers.

Idiopathic postprandial syndrome, colloquially but incorrectly known by some as hypoglycemia, describes a collection of clinical signs and symptoms similar to medical hypoglycemia but without the demonstrably low blood glucose levels which characterise said condition.

People with this condition suffer from recurrent episodes of altered mood and cognitive efficiency, often accompanied by weakness and adrenergic symptoms such as shakiness. The episodes typically occur a few hours after a meal, rather than after many hours of fasting. The principal treatments recommended are extra small meals or snacks and avoidance of excessive simple sugars.