A thorough history is essential and should cover family history, diet; drug/toxin exposure social history, including tobacco and alcohol use; and occupational background, with details on whether similar cases exist among coworkers. Treatment of any chronic disease such as pernicious anemia should always be elucidated.

In most cases of nutritional/toxic optic neuropathy, the diagnosis may be obtained via detailed medical history and eye examination. Additionally, supplementary neurological imaging studies, such as MRI or enhanced CT, may be performed if the cause remains unclear.

When the details of the examination and history indicate a familial history of similar ocular or systemic disease, whether or not there is evidence of toxic or nutritional causes for disease, certain genetic tests may be required. Because there are several congenital causes of mitochondrial dysfunction, the patients history, examination, and radiological studies must be examined in order to determine the specific genetic tests required. For example, 90% of cases of Leber’s Hereditary Optic Neuropathy (LHON) are associated with three common mtDNA point mutations (m.3460G>A/MT-ND1, m.11778G>A/MT-ND4, m.14484T>C/MT-ND6) while a wider range of mtDNA mutations (MT-ND1, MT-ND5, MT-ND6; http://www.mitomap.org/) have been associated with overlapping phenotypes of LHON, MELAS, and Leigh syndrome.

There is no cure for this condition. Treatment is supportive and varies depending on how symptoms present and their severity. Some degree of developmental delay is expected in almost all cases of M-CM, so evaluation for early intervention or special education programs is appropriate. Rare cases have been reported with no discernible delay in academic or school abilities.

Physical therapy and orthopedic bracing can help young children with gross motor development. Occupational therapy or speech therapy may also assist with developmental delays. Attention from an orthopedic surgeon may be required for leg length discrepancy due to hemihyperplasia.

Children with hemihyperplasia are thought to have an elevated risk for certain types of cancers. Recently published management guidelines recommend regular abdominal ultrasounds up to age eight to detect Wilms' tumor. AFP testing to detect liver cancer is not recommended as there have been no reported cases of hepatoblastoma in M-CM patients.

Congenital abnormalities in the brain and progressive brain overgrowth can result in a variety of neurological problems that may require intervention. These include hydrocephalus, cerebellar tonsillar herniation (Chiari I), seizures and syringomyelia. These complications are not usually congenital, they develop over time often presenting complications in late infancy or early childhood, though they can become problems even later. Baseline brain and spinal cord MRI imaging with repeat scans at regular intervals is often prescribed to monitor the changes that result from progressive brain overgrowth.

Assessment of cardiac health with echocardiogram and EKG may be prescribed and arrhythmias or abnormalities may require surgical treatment.

Prognosis varies widely depending on severity of symptoms, degree of intellectual impairment, and associated complications. Because the syndrome is rare and so newly identified, there are no long term studies.

Recent research has been focused on studying large series of cases of 3-M syndrome to allow scientists to obtain more information behind the genes involved in the development of this disorder. Knowing more about the underlying mechanism can reveal new possibilities for treatment and prevention of genetic disorders like 3-M syndrome.

- One study looks at 33 cases of 3M syndrome, 23 of these cases were identified as CUL7 mutations: 12 being homozygotes and 11 being heterozygotes. This new research shows genetic heterogeneity in 3M syndrome, in contrast to the clinical homogeneity. Additional studies are still ongoing and will lead to the understanding of this new information.

- This study provides more insight on the three genes involved in 3M syndrome and how they interact with each other in normal development. It lead to the discovery that the CUL7, OBS1, and CCDC8 form a complex that functions to maintain microtubule and genomic integrity.

Treatment of 3-M syndrome is aimed at the specific symptoms presented in each individual. With the various symptoms of this disorder being properly managed and affected individuals having normal mental development, 3-M syndrome is not a life - threatening condition and individuals are able to lead a near normal life with normal life expectancy.

Treatment may involve the coordinated efforts of many healthcare professionals, such as pediatricians, orthopedists, dentists and/or other specialists depending on the symptoms.

- Possible management options for short stature are surgical bone lengthening or growth hormone therapy.

- Orthopedic techniques and surgery may be used to treat certain skeletal abnormalities.

- Plastic surgery may also be performed on individuals to help correct certain cranio-facial anomalies.

- Individuals with dental abnormalities may undergo corrective procedures such as braces or oral surgeries.

Those diseases understood as congenital in origin could either be specific to the ocular organ system (LHON, DOA) or syndromic (MELAS, Multiple Sclerosis). It is estimated that these inherited optic neuropathies in the aggregate affect 1 in 10,000

Of the acquired category, disease falls into further etiological distinction as arising from toxic (drugs or chemicals) or nutritional/metabolic (vitamin deficiency/diabetes) insult. It is worth mentioning that under-nutrition and toxic insult can occur simultaneously, so a third category may be understood as having a combined or mixed etiology. We will refer to this as Toxic/Nutritional Optic Neuropathy, whereby nutritional deficiencies and toxic/metabolic insults are the simultaneous culprits of visual loss associated with damage and disruption of the RGC and optic nerve mitochondria.

Immunoprecipitation, immunoblotting and enzyme-link immunosorbent assay (ELISA)

Poot et al. 2013 determined that immunoprecipitation for antibodies against envoplakin and periplakin or alpha2-macroglobulin-like–1 is the most sensitive test. However, alpha2-macroglobulin-like-1 can also be detected in patients with toxic epidermal necrosis.

Marshall–Smith syndrome is not to be confused with:

- Marshall syndrome (aka.Periodic fever, aphthous stomatitis, pharyngitis and adenitis (PFAPA syndrome, see also: Periodic fever syndrome)

- Sotos (like) syndrome

- Weaver-Smith syndrome (WSS)

In order to determine if the patient is afflicted with paraneoplastic pemphigus, several tests may be performed. Initially, samples are obtained via skin biopsy for routine microscopy and direct immunofluorescence (DIF) testing. The skin sample should be obtained from an unaffected area adjacent to a lesion. Testing in more detail follows depending on the results from the DIF. Prompt diagnosis of PNP is crucial due to the high mortality rate of the disease.

Camisa and Helm revised the original criteria from Anhalt et al. into major and minor signs indicating PNP:

Major:

- Polymorphic mucocutaneous eruption

- Concurrent internal tumor

- Serum antibodies with a specific immunoprecipitation pattern

Minor:

- Histologic evidence of acantholysis (loss of intercellular connections leading to breaking apart of the skin; lesion)

- Direct immunofluorescence showing intercellular and basement membrane staining

- Indirect immunofluorescence staining with rat bladder epithelium

Respiratory complications are often cause of death in early infancy.

To classify an individual as TOFI, it is essential to measure their internal fat content. This done by using magnetic resonance Imaging (MRI) or CT scanning. The parameters of the MRI scanner are manipulated to show fat as bright (white) and lean tissue as dark.

Indirect methods such as waist circumference are not suitable as individuals with an identical waist circumference can have vastly different levels of internal fat. The figure clearly shows that despite having an identical waist circumference (in this example all men had a waist of 84 cm), there is considerable variation in the amount of visceral fat (volumes shown on the image in litres) present.

Currently, no treatment slows the neurodegeneration in any of the neuroacanthocytosis disorders. Medication may be administered to decrease the involuntary movements produced by these syndromes. Antipsychotics are used to block dopamine, anticonvulsants treat seizures and botulinum toxin injections may control dystonia. Patients usually receive speech, occupational and physical therapies to help with the complications associated with movement. Sometimes, physicians will prescribe antidepressants for the psychological problems that accompany neuroacanthocytosis. Some success has been reported with Deep brain stimulation.

Mouthguards and other physical protective devices may be useful in preventing damage to the lips and tongue due to the orofacial chorea and dystonia typical of chorea acanthocytosis.

While Gilbert's syndrome is considered harmless, it is clinically important because it may give rise to a concern about a blood or liver condition, which could be more dangerous. However, these conditions have additional indicators:

- Hemolysis can be excluded by a full blood count, haptoglobin, lactate dehydrogenase levels, and the absence of reticulocytosis (elevated reticulocytes in the blood would usually be observed in haemolytic anaemia).

- Viral hepatitis can be excluded by negative blood samples for antigens specific to the different hepatitis viruses.

- Cholestasis can be excluded by normal levels of bile acids in plasma, the absence of lactate dehydrogenase, low levels of conjugated bilirubin, and ultrasound scan of the bile ducts.

- More severe types of glucuronyl transferase disorders such as Crigler–Najjar syndrome (types I and II) are much more severe, with 0–10% UGT1A1 activity, with sufferers at risk of brain damage in infancy (type I) and teenage years (type II).

- Dubin–Johnson syndrome and Rotor syndrome are rarer autosomal recessive disorders characterized by an increase of conjugated bilirubin.

- In GS, unless another disease of the liver is also present, the liver enzymes ALT/SGPT and AST/SGOT, as well as albumin, are within normal ranges.

Purpura hemorrhagica may be prevented by proper management during an outbreak of strangles. This includes isolation of infected horses, disinfection of fomites, and good hygiene by caretakers. Affected horses should be isolated at least one month following infection. Exposed horses should have their temperature taken daily and should be quarantined if it becomes elevated. Prophylactic antimicrobial treatment is not recommended.

Vaccination can reduce the incidence and severity of the disease. However, horses with high SeM antibody titers are more likely to develop purpura hemorrhagica following vaccination and so these horses should not be vaccinated. Titers may be measured by ELISA.

This is difficult to establish in the general population since the necessary imaging examinations are time consuming and expensive; however, in a recent research study it was estimated that 14% of the men and 12% of the women scanned with a BMI 20–25 kg/m were classified as TOFI.

There are 3 possible ways to test the fetal antigen status. Free Cell DNA, Amniocentesis, and Chorionic Villus Sampling. Of the three, CVS is no longer used due to risk of worsening the maternal antibody response. Once antigen status has been determined, assessment may be done with MCA scans.

- Free Cell DNA can be run on certain antigens. Blood is taken from the mother, and using PCR, can detect the K, C, c, D, and E alleles of fetal DNA. This blood test is non-invasive to the fetus and is an easy way of checking antigen status and risk of HDN. Testing has proven very accurate and is routinely done in the UK at the International Blood Group Reference Laboratory in Bristol. Sanequin laboratory in Amsterdam, Netherlands also performs this test. For US patients, blood may be sent to either of the labs. In the US, Sensigene is done by Sequenome to determine fetal D status. Sequenome does not accept insurance in the US, but US and Canadian patients have had insurance cover the testing done overseas.

- Amniocentesis is another recommended method for testing antigen status and risk for HDN. Fetal antigen status can be tested as early as 15 weeks by PCR of fetal cells.

- CVS is possible as well to test fetal antigen status but is not recommended. CVS carries a higher risk of fetal maternal hemorrhage and can raise antibody titers, potentially worsening the antibody effect.

Testing for HDN involves blood work from both mother and father, and may also include assessment with amniocentesis and Middle Cerebral Artery scans.

Many other neurological conditions are associated with acanthocytosis but are not considered 'core' acanthocytosis syndromes. The commonest are:

- Pantothenate kinase-associated neurodegeneration, an autosomal recessive condition caused by mutations in "PANK2".

- Huntington's disease-like syndrome type 2, an autosomal dominant condition caused by mutations in "JPH3" that closely resembles Huntington's disease.

- Bassen-Kornzweig disease, or Bassen-Kornzweig Syndrome (see also History).

- Levine-Critchley syndrome (see History).

- Paroxysmal movement disorders associated with GLUT1 mutations.

- Familial acanthocytosis with paroxysmal exertion-induced dyskinesias and epilepsy (FAPED).

- Some cases of mitochondrial disease.

Typically no treatment is needed. If jaundice is significant phenobarbital may be used.

It is not lethal in nature and is responsive to tetracycline or ciprofloxacin. Surgical treatment include rhinoplasty. However, if left untreated the disease can lead to sepsis, bleeding, or other chronic conditions that can be fatal.

Electron microscopy can reveal the bullet-shaped rhabdovirus, but is not

adequate for definitive diagnosis.

The Manual or Diagnostic for Aquatic Animals, 2006, is the standard

reference for definitive tests. In most cases, cell culturization

is recommended for surveillance, with antibody tests and reverse transcription

polymerase chain reaction (RT-PCR) and genetic sequencing and comparison

for definitive confirmation and genotype classification.

Virus neutralisation is another important method of diagnosis, especially for carrier fish.

Along with obtaining a complete medical history, a series of biochemical tests are required in order to arrive at an accurate diagnosis that verifies the presence of the illness. In addition, imaging of the kidneys (for structure and presence of two kidneys) is sometimes carried out, and/or a biopsy of the kidneys. The first test will be a urinalysis to test for high levels of proteins, as a healthy subject excretes an insignificant amount of protein in their urine. The test will involve a 24-hour bedside urinary total protein estimation. The urine sample is tested for proteinuria (>3.5 g per 1.73 m per 24 hours). It is also examined for urinary casts, which are more a feature of active nephritis. Next a blood screen, comprehensive metabolic panel (CMP) will look for hypoalbuminemia: albumin levels of ≤2.5 g/dL (normal=3.5-5 g/dL). Then a Creatinine Clearance C test will evaluate renal function particularly the glomerular filtration capacity. Creatinine formation is a result of the breakdown of muscular tissue, it is transported in the blood and eliminated in urine. Measuring the concentration of organic compounds in both liquids evaluates the capacity of the glomeruli to filter blood. Electrolytes and urea levels may also be analysed at the same time as creatinine (EUC test) in order to evaluate renal function.

A lipid profile will also be carried out as high levels of cholesterol (hypercholesterolemia), specifically elevated LDL, usually with concomitantly elevated VLDL, is indicative of nephrotic syndrome.

A kidney biopsy may also be used as a more specific and invasive test method. A study of a sample’s anatomical pathology may then allow the identification of the type of glomerulonephritis involved. However, this procedure is usually reserved for adults as the majority of children suffer from minimum change disease that has a remission rate of 95% with corticosteroids. A biopsy is usually only indicated for children that are "corticosteroid resistant" as the majority suffer from focal and segmental glomeruloesclerosis.

Further investigations are indicated if the cause is not clear including analysis of auto-immune markers (ANA, ASOT, C3, cryoglobulins, serum electrophoresis), or ultrasound of the whole abdomen.

There are 3 possible ways to test the fetal antigen status. Free Cell DNA, Amniocentesis, and Chorionic Villus Sampling. Of the three, CVS is no longer used due to risk of worsening the maternal antibody response. Once antigen status has been determined, assessment may be done with MCA scans.

- Free Cell DNA can be run on certain antigens. Blood is taken from the mother, and using PCR, can detect the K, C, c, D, and E alleles of fetal DNA. This blood test is non-invasive to the fetus and is an easy way of checking antigen status and risk of HDN. Testing has proven very accurate and is routinely done in the UK at the International Blood Group Reference Laboratory in Bristol. Sanequin laboratory in Amsterdam, Netherlands also performs this test. For US patients, blood may be sent to either of the labs. In the US, Sensigene is done by Sequenome to determine fetal D status. Sequenome does not accept insurance in the US, but US and Canadian patients have had insurance cover the testing done overseas.

- Amniocentesis is another recommended method for testing antigen status and risk for HDN. Fetal antigen status can be tested as early as 15 weeks by PCR of fetal cells.

- CVS is possible as well to test fetal antigen status but is not recommended. CVS carries a higher risk of fetal maternal hemorrhage and can raise antibody titers, potentially worsening the antibody effect.

There are 3 possible ways to test the fetal antigen status. Free Cell DNA, Amniocentesis, and Chorionic Villus Sampling. Of the three, CVS is no longer used due to risk of worsening the maternal antibody response. Once antigen status has been determined, assessment may be done with MCA scans.

- Free Cell DNA can be run on certain antigens. Blood is taken from the mother, and using PCR, can detect the K, C, c, D, and E alleles of fetal DNA. This blood test is non-invasive to the fetus and is an easy way of checking antigen status and risk of HDN. Testing has proven very accurate and is routinely done in the UK at the International Blood Group Reference Laboratory in Bristol. Sanequin laboratory in Amsterdam, Netherlands also performs this test. For US patients, blood may be sent to either of the labs. In the US, Sensigene is done by Sequenome to determine fetal D status. Sequenome does not accept insurance in the US, but US and Canadian patients have had insurance cover the testing done overseas.

- Amniocentesis is another recommended method for testing antigen status and risk for HDN. Fetal antigen status can be tested as early as 15 weeks by PCR of fetal cells.

- CVS is possible as well to test fetal antigen status but is not recommended. CVS carries a higher risk of fetal maternal hemorrhage and can raise antibody titers, potentially worsening the antibody effect.

MCA scans Middle cerebral artery - peak systolic velocity is changing the way sensitized pregnancies are managed. This test is done noninvasively with ultrasound. By measuring the peak velocity of blood flow in the middle cerebral artery, a MoM (multiple of the median) score can be calculated. MoM of 1.5 or greater indicates severe anemia and should be treated with IUT.

Preliminary diagnosis involves histopathological examination,

observing tissues through a microscope. Most tissue changes can be observed

as minor to major necrosis (cell death) in the liver, kidneys, spleen, and

skeletal muscle. The hematopoietic (blood-forming) areas of the kidney and

spleen are the initial area of infection, and should show necrosis.

The gill may have thickened lamellae, and the liver may have pyknotic nuclei.

Skeletal muscle accumulates blood but does not suffer much damage.