Diagnosis is suspected according to signs and symptoms, such as skin changes, abnormal growth, and loss of hair. A genetic test for LMNA mutations can confirm the diagnosis of progeria.

As there is no known cure, few people with progeria exceed 13 years of age. At least 90% of patients die from complications of atherosclerosis, such as heart attack or stroke.

Mental development is not adversely affected; in fact, intelligence tends to be average to above average. With respect to the features of aging that progeria appears to manifest, the development of symptoms is comparable to aging at a rate eight to ten times faster than normal. With respect to features of aging that progeria does not exhibit, patients show no neurodegeneration or cancer predisposition. They also do not develop conditions that are commonly associated with aging, such as cataracts (caused by UV exposure) and osteoarthritis.

Although there may not be any successful treatments for progeria itself, there are treatments for the problems it causes, such as arthritic, respiratory, and cardiovascular problems. Sufferers of progeria have normal reproductive development and there are known cases of women with progeria who had delivered healthy offspring.

A cure for Werner syndrome has not yet been discovered. It is often treated by managing the associated diseases and relieving symptoms to improve quality of life. The skin ulcers that accompany WS can be treated in several ways, depending on the severity. Topical treatments can be used for minor ulcers, but are not effective in preventing new ulcers from occurring. In the most severe cases, surgery may be required to implant a skin graft or amputate a limb if necessary. Diseases commonly associated with Werner Syndrome such as diabetes and cancer are treated in generally the same ways as they would be for a non-Werner Syndrome individual. A change in diet & exercise can help prevent and control arteriosclerosis, and regular cancer screenings can allow for early detection of cancer.

There is recent evidence that suggests that the cytokine-suppressive anti-inflammatory drug, SB203580, may be a possible therapeutic option for patients with Werner's Syndrome. This drug targets the p38 signaling pathway, which may become activated as a result of genomic instability and stalled replication forks that are characteristic mutations in WS. This activation of p38 may play a role in the onset of premature cell aging, skin aging, cataracts, and graying of the hair. The p38 pathway has also been implicated in the anti-inflammatory response that causes atherosclerosis, diabetes, and osteoporosis, all of which are associated with Werner's Syndrome. This drug has shown to revert the aged characteristics of young WS cells to those seen in normal, young cells and improve the lifespan of WS cells "in vitro". SB203580 is still in the clinical trial stages, and the same results have not yet been seen "in vivo".

In 2010, vitamin C supplementation was found to reverse the premature aging and several tissue dysfunctions in a genetically modified mouse model of the disease. Vitamin C supplementation also appeared to normalize several age-related molecular markers such as the increased levels of the transcription factor NF-κB. In addition, it decreases activity of genes activated in human Werner syndrome and increases gene activity involved in tissue repair. Supplementation of vitamin C is suspected to be beneficial in the treatment of human Werner syndrome, although there was no evidence of anti-aging activity in nonmutant mice. In general, treatments are available for only the symptoms or complications and not for the disease itself.

An OI diagnosis can be confirmed through DNA or collagen testing, but in many cases the occurrence of bone fractures with little trauma and the presence of other clinical features such as blue sclera are sufficient for a diagnosis. A skin biopsy can be performed to determine the structure and quantity of type I collagen. DNA testing can confirm the diagnosis, however, it cannot exclude it because not all mutations causing OI are known and/or tested for. OI type II is often diagnosed by ultrasound during pregnancy, where already multiple fractures and other characteristic features may be present. Relative to control, OI cortical bone shows increased porosity, canal diameter, and connectivity in micro-computed tomography.

An important differential diagnosis of OI is child abuse, as both may present with multiple fractures in various stages of healing. Differentiating them can be difficult, especially when no other characteristic features of OI are present. Other differential diagnoses include rickets, osteomalacia, and other rare skeletal syndromes.

Neuroimaging, usually with computed tomography (CT/CAT) or magnetic resonance imaging (MRI), is used to exclude any mass lesions. In IIH these scans typically appear to be normal, although small or slit-like ventricles, dilatation and buckling of the optic nerve sheaths and "empty sella sign" (flattening of the pituitary gland due to increased pressure) and enlargement of Meckel's caves may be seen.

An MR venogram is also performed in most cases to exclude the possibility of venous sinus stenosis/obstruction or cerebral venous sinus thrombosis. A contrast-enhanced MRV (ATECO) scan has a high detection rate for abnormal transverse sinus stenoses. These stenoses can be more adequately identified and assessed with catheter cerebral venography and manometry. Buckling of the bilateral optic nerves with increased perineural fluid is also often noted on MRI imaging.

Lumbar puncture is performed to measure the opening pressure, as well as to obtain cerebrospinal fluid (CSF) to exclude alternative diagnoses. If the opening pressure is increased, CSF may be removed for transient relief (see below). The CSF is examined for abnormal cells, infections, antibody levels, the glucose level, and protein levels. By definition, all of these are within their normal limits in IIH. Occasionally, the CSF pressure measurement may be normal despite very suggestive symptoms. This may be attributable to the fact that CSF pressure may fluctuate over the course of the normal day. If the suspicion of problems remains high, it may be necessary to perform more long-term monitoring of the ICP by a pressure catheter.

The opioid antagonist naloxone allowed a woman with congenital insensitivity to pain to experience it for the first time. Similar effects were observed in Na1.7 null mice treated with naloxone. As such, opioid antagonists like naloxone and naltrexone may be effective in treating the condition.

The original criteria for IIH were described by Dandy in 1937.

They were modified by Smith in 1985 to become the "modified Dandy criteria". Smith included the use of more advanced imaging: Dandy had required ventriculography, but Smith replaced this with computed tomography. In a 2001 paper, Digre and Corbett amended Dandy's criteria further. They added the requirement that the patient is awake and alert, as coma precludes adequate neurological assessment, and require exclusion of venous sinus thrombosis as an underlying cause. Furthermore, they added the requirement that no other cause for the raised ICP is found.

In a 2002 review, Friedman and Jacobson propose an alternative set of criteria, derived from Smith's. These require the absence of symptoms that could not be explained by a diagnosis of IIH, but do not require the actual presence of any symptoms (such as headache) attributable to IIH. These criteria also require that the lumbar puncture is performed with patient lying sideways, as a lumbar puncture performed in the upright sitting position can lead to artificially high pressure measurements. Friedman and Jacobson also do not insist on MR venography for every patient; rather, this is only required in atypical cases (see "diagnosis" above).

Werner syndrome (WS), also known as "adult progeria", is a rare, autosomal recessive disorder which is characterized by the appearance of premature aging.

Werner syndrome is named after the German scientist Otto Werner. He identified the syndrome in four siblings observed with premature aging, which he explored as the subject of his dissertation of 1904.

It has a global incidence rate of less than 1 in 100,000 live births (although incidence in Japan and Sardinia is higher, affecting 1 in 20,000–40,000 and 1 in 50,000, respectively). 1,300 cases had been reported as of 2006. Affected individuals typically grow and develop normally until puberty; the mean age of diagnosis is twenty-four, often realized when the adolescent growth spurt is not observed. The youngest person diagnosed was six years old. The median and mean ages of death are 47–48 and 54 years, respectively. The main cause of death is cardiovascular disease or cancer.

More than 1 in 2 people with OI also have dentinogenesis imperfecta (DI) - a congenital disorder of formation of dentine. Dental treatment may pose as a challenge as a result of the various deformities, skeletal and dental, due to OI. Children with OI should go for a dental check-up as soon as their teeth erupt, this may minimize tooth structure loss as a result of abnormal dentine, and they should be monitored regularly to preserve their teeth and oral health.

Some cases of myotonia congenita do not require treatment, or it is determined that the risks of the medication outweigh the benefits. If necessary, however, symptoms of the disorder may be relieved with quinine, phenytoin, carbamazepine, mexiletine and other anticonvulsant drugs. Physical therapy and other rehabilitative measures may also be used to help muscle function. Genetic counseling is available.

Congenital insensitivity to pain (CIP), also known as congenital analgesia, is one or more rare conditions in which a person cannot feel (and has never felt) physical pain. The conditions described here are separate from the HSAN group of disorders, which have more specific signs and cause. Because feeling physical pain is vital for survival, CIP is an extremely dangerous condition. It is common for people with the condition to die in childhood due to injuries or illnesses going unnoticed. Burn injuries are one of the more common injuries.

As of today, no agreed-upon treatment of Dent's disease is known and no therapy has been formally accepted. Most treatment measures are supportive in nature:

- Thiazide diuretics (i.e. hydrochlorothiazide) have been used with success in reducing the calcium output in urine, but they are also known to cause hypokalemia.

- In rats with diabetes insipidus, thiazide diuretics inhibit the NaCl cotransporter in the renal distal convoluted tubule, leading indirectly to less water and solutes being delivered to the distal tubule. The impairment of Na transport in the distal convoluted tubule induces natriuresis and water loss, while increasing the reabsorption of calcium in this segment in a manner unrelated to sodium transport.

- Amiloride also increases distal tubular calcium reabsorption and has been used as a therapy for idiopathic hypercalciuria.

- A combination of 25 mg of chlorthalidone plus 5 mg of amiloride daily led to a substantial reduction in urine calcium in Dent's patients, but urine pH was "significantly higher in patients with Dent’s disease than in those with idiopathic hypercalciuria (P < 0.03), and supersaturation for uric acid was consequently lower (P < 0.03)."

- For patients with osteomalacia, vitamin D or derivatives have been employed, apparently with success.

- Some lab tests on mice with CLC-5-related tubular damage showed a high-citrate diet preserved kidney function and delayed progress of kidney disease.

Dwarfism is often diagnosed in childhood on the basis of visible symptoms. A physical examination can usually suffice to diagnose certain types of dwarfism, but genetic testing and diagnostic imaging may be used to determine the exact condition. In a person's youth, growth charts that track height can be used to diagnose subtle forms of dwarfism that have no other striking physical characteristics.

Short stature or stunted growth during youth is usually what brings the condition to medical attention. Skeletal dysplasia is usually suspected because of obvious physical features (e.g., unusual configuration of face or shape of skull), because of an obviously affected parent, or because body measurements (arm span, upper to lower segment ratio) indicate disproportion. Bone X-rays are often key to diagnosing a specific skeletal dysplasia, but are not the sole diagnostic tool. Most children with suspected skeletal dysplasias are referred to a genetics clinic for diagnostic confirmation and genetic counseling. Since about the year 2000, genetic tests for some of the specific disorders have become available.

During an initial medical evaluation of shortness, the absence of disproportion and other clues listed above usually indicates causes other than bone dysplasias.

Many types of dwarfism are currently impossible to prevent because they are genetically caused. Genetic conditions that cause dwarfism may be identified with genetic testing, by screening for the specific variations that result in the condition. However, due to the number of causes of dwarfism, it may be impossible to determine definitively if a child will be born with dwarfism.

Dwarfism resulting from malnutrition or a hormonal abnormality may be treated with an appropriate diet or hormonal therapy. Growth hormone deficiency may be remedied via injections of human growth hormone (HGH) during early life.

In northern Scandinavia, the prevalence of myotonia congenita has been estimated at 1:10,000.

Myotonia congenita is estimated to affect 1 in 1,000,000 people worldwide.

The standard treatment for DIPG is 6 weeks of radiation therapy, which often dramatically improves symptoms. However, symptoms usually recur after 6 to 9 months and progress rapidly.

Dent disease 2 (nephrolithiasis type 2) is associated with the "OCRL" gene. Both Lowe syndrome (oculocerebrorenal syndrome) and Dent disease can be caused by truncating or missense mutations in "OCRL".

Surgery to attempt tumour removal is usually not possible or advisable for DIPG. By nature, these tumours invade diffusely throughout the brain stem, growing between normal nerve cells. Aggressive surgery would cause severe damage to neural structures vital for arm and leg movement, eye movement, swallowing, breathing, and even consciousness.

A neurosurgically performed brain-stem biopsy for immunotyping of diffuse intrinsic pontine glioma has served a limited recent role in experimental clinical studies and treatment trials. This however is not the current standard of care as it presents considerable risk given the biopsy location, and thus is appropriately performed in the context of participation in an ongoing clinical treatment trial.

Pontine biopsy is in no way a therapeutic or curative surgery, and the risks (potentially catastrophic and fatal) are only outweighed when the diagnosis is uncertain (extremely unusual) or the patient is enrolled in an approved clinical trial.

The standard work-up for AT/RT includes:

- Magnetic resonance imaging (MRI) of the brain and spine

- Lumbar puncture to look for M1 disease

- Computed tomography (CT) of chest and abdomen to check for a tumor

- Bone marrow aspiration to check for bone tumors. Sometimes the physician will perform a stem cell transplant

- Bone marrow biopsy

- Bone scan

The initial diagnosis of a tumor is made with a radiographic study (MRI or CT-). If CT was performed first, an MRI is usually performed as the images are often more detailed and may reveal previously undetected metastatic tumors in other locations of the brain. In addition, an MRI of the spine is usually performed. The AT/RT tumor often spreads to the spine. AT/RT is difficult to diagnose only from radiographic study; usually, a pathologist must perform a cytological or genetic analysis.

Examination of the cerebrospinal fluid is important (CSF), as one-third of patients will have intracranial dissemination with involvement of the CSF. Large tumor cells, eccentricity of the nuclei, and prominent nucleoli are consistent findings. Usually only a minority of AT/RT biopsies have rhabdoid cells, making diagnosis more difficult. Increasingly it is recommended that a genetic analysis be performed on the brain tumor, especially to find if a deletion in the INI1/hSNF5 gene is involved (appears to account for over 80% of the cases). The correct diagnosis of the tumor is critical to any protocol. Studies have shown that 8% to over 50% of AT/RT tumors are diagnosed incorrectly.

Adson's sign and the costoclavicular maneuver lack specificity and sensitivity and should comprise only a small part of the mandatory comprehensive history and physical examination undertaken with a patient suspected of having TOS. There is currently no single clinical sign that makes the diagnosis of TOS with any degree of certainty.

Additional maneuvers that may be abnormal in TOS include Wright's Test, which involves hyperabducting the arms over the head with some extension and evaluating for loss of radial pulses or signs of blanching of the skin in the hands indicating a decrease in blood flow with the maneuver. The "compression test" is also used, exerting pressure between the clavicle and medial humeral head causes radiation of pain and/or numbness into the affected arm.

Doppler arteriography, with probes at the fingertips and arms, tests the force and "smoothness" of the blood flow through the radial arteries, with and without having the patient perform various arm maneuvers (which causes compression of the subclavian artery at the thoracic outlet). The movements can elicit symptoms of pain and numbness and produce graphs with diminished arterial blood flow to the fingertips, providing strong evidence of impingement of the subclavian artery at the thoracic outlet. Doppler arteriography does not utilize probes at the fingertips and arms, and in this case is likely being confused with plethysmography, which is a different method that utilizes ultrasound without direct visualization of the affected vessels. It should also be noted that Doppler ultrasound (not really 'arteriography') would not be used at the radial artery in order to make the diagnosis of TOS. Finally, even if a Doppler study of the appropriate artery were to be positive, it would not diagnose neurogenic TOS, by far the most common subtype of TOS. There is plenty of evidence in the medical literature to show that arterial compression does not equate to brachial plexus compression, although they may occur together, in varying degrees. Additionally, arterial compression by itself does not make the diagnosis of arterial TOS (the rarest form of TOS). Lesser degrees of arterial compression have been shown in normal individuals in various arm positions and are thought to be of little significance without the other criteria for arterial TOS.

Hyperparathyroidism is present in ≥ 90% of patients. Asymptomatic hypercalcemia is the most common manifestation: about 25% of patients have evidence of nephrolithiasis or nephrocalcinosis. In contrast to sporadic cases of hyperparathyroidism, diffuse hyperplasia or multiple adenomas are more common than solitary adenomas.

Video game-related health problems can induce repetitive strain injuries, skin disorders or other health issues. Other problems include video game-provoked seizures in patients with epilepsy. In rare and extreme cases, deaths have resulted from excessive video game playing (see Deaths due to video game addiction).

Multiple endocrine neoplasia type 1 (MEN-1 syndrome) or Wermer's syndrome is part of a group of disorders, the multiple endocrine neoplasias, that affect the endocrine system through development of neoplastic lesions in pituitary, parathyroid gland and pancreas.

AT/RTs can occur at any sites within the CNS; however, about 60% are located in the posterior fossa or cerebellar area. The ASCO study showed 52% posterior fossa; 39% sPNET; 5% pineal; 2% spinal, and 2% multifocal.

The tumors' appearance on CT and MRI are not specific, tending towards large size, calcifications, necrosis (tissue death), and hemorrhage (bleeding). Radiological studies alone cannot identify AT/RT; a pathologist almost always has to evaluate a brain tissue sample.

The increased cellularity of the tumor may make the appearance on an uncontrasted CT to have increased attenuation. Solid parts of the tumor often enhance with contrast MRI finding on T1 and T2 weighted images are variable. Precontrast T2 weighted images may show an isosignal or slightly hypersignal. Solid components of the tumor may enhance with contrast, but not always. MRI studies appear to be more able to pick up metastatic foci in other intracranial locations, as well as intraspinal locations.

Preoperative and follow-up studies are needed to detect metastatic disease.

School-age children with unilateral hearing loss tend to have poorer grades and require educational assistance. This is not the case with everyone, however. They can also be perceived to have behavioral issues.

People afflicted with UHL have great difficulty locating the source of any sound. They may be unable to locate an alarm or a ringing telephone. The swimming game Marco Polo is generally impossible for them.

When wearing stereo headphones, people with unilateral hearing loss can hear only one channel, hence the panning information (volume and time differences between channels) is lost; some instruments may be heard better than others if they are mixed predominantly to one channel, and in extreme cases of sound production, such as complete stereo separation or stereo-switching, only part of the composition can be heard; in games using 3D audio effects, sound may not be perceived appropriately due to coming to the disabled ear. This can be corrected by using settings in the software or hardware—audio player, OS, amplifier or sound source—to adjust balance to one channel (only if the setting downmixes sound from both channels to one), or there may be an option to outright downmix both channels to mono. Such settings may be available via the device or software's accessibility features. As hardware solutions, stereo-to-mono adapters may be available to receive mono sound in stereo headphones from a stereo sound source, or some monaural headsets for cellphones and VOIP communication may combine stereo sound to mono (though headphones for voice communication typically offer lower audio quality than headphones targeted for listening to music). From the standpoint of sound fidelity, sound information in downmixed mono channel will, in any case, differ from that in either of the source channels or what is perceived by a normal-hearing person, thus technically some audio quality is lost (for example, the same or slightly different sound occurrences in two channels, with time delay between them, will be merged to a sound in the mono channel that unavoidably cannot correspond to the intent of the sound producer); however, such loss is most probably unnoticeable, especially compared to other distortions inherent in sound reproduction, and to the person's problems from hearing loss.