It is difficult to determine the prevalence of hyperprolinemia type I, as many people with the condition are asymptomatic.

People with hyperprolinemia type I have proline levels in their blood between 3 and 10 times the normal level. Some individuals with type I exhibit seizures, intellectual disability, or other neurological problems.

On 9 May 2014, the UK National Screening Committee (UK NSC) announced its recommendation to screen every newborn baby in the UK for four further genetic disorders as part of its NHS Newborn Blood Spot Screening programme, including isovaleric acidemia.

A 2005 study on rats suggested that hyperprolininemia causes cognitive dysfunction.

The urine of newborns can be screened for isovaleric acidemia using mass spectrometry, allowing for early diagnosis. Elevations of isovalerylglycine in urine and of isovalerylcarnitine in plasma are found.

Brain MRI shows vermis atrophy or hypoplasic. Cerebral and cerebellar atrophy with white matter changes in some cases.

Diagnosis of the lipid storage disorders can be achieved through the use of several tests. These tests include clinical examination, biopsy, genetic testing, molecular analysis of cells or tissues, and enzyme assays. Certain forms of this disease can also be diagnosed through urine testing which will detect the stored material. Prenatal testing is also available to determine if the fetus will have the disease or is a carrier.

In terms of the diagnosis for glycogen storage disease type III, the following tests/exams are carried out to determine if the individual has the condition:

- Biopsy (muscle or liver)

- CBC

- Ultrasound

- DNA mutation analysis (helps ascertain GSD III subtype)

Diagnosis of otodental syndrome was established using clinical, histopathological and audiometric methodologies. In normal individuals, by the age of 2-3, radiograph images should depict any signs of premolar development. A formal diagnosis of no premolar growth can be done by age 6 in order to check for signs of otodental syndrome. Sensorineural hearing loss can be another measure for proper diagnosis as well as checking for ocular coloboma. The latter is usually noticed at an around birth.

Molecular genetic testing can aid in the diagnosis of the affected individual, which would determine if there are any abnormalities in the FGF3 gene (11q13) or the FADD gene (11q13.3). Additional tests that can help diagnose otodental syndrome are ear infection tests, hearing tests, oral examination, and eye examinations to check for the specific phenotypic associations. Due to the rarity of otodental syndrome, most symptoms are looked at on an individual basis unless multiple symptoms are all apparent at once.

There is potential for differential diagnosis due to similarities in symptoms. Other diseases that share common symptoms are chondroectodermal dysplasia, achondrodysplasia, and osteopetrosis

The differential diagnosis of glycogen storage disease type III includes GSD I, GSD IX and GSD VI. This however does not mean other glycogen storage diseases should not be distinguished as well.

In a sample of 19 children, a 1997 study found that 3 died before the age of 3, and 2 never learned to walk. The children had various levels of delayed development with developmental quotients from 60 to 85.

Depending on clinical status and the blood ammonia level, the logical first step is to reduce protein intake and to attempt to maintain energy intake. Initiate intravenous infusion of 10% glucose (or higher, if administered through a central line) and lipids.

Intravenous sodium benzoate and sodium phenylacetate may be helpful. Arginine is usually administered with benzoate and phenylacetate. This is best administered in the setting of a major medical center where facilities for hemodialysis in infants is available.

Glycerol phenylbutyrate is a pre-prodrug that undergoes metabolism to form phenylacetate. Results of a phase 3 study comparing ammonia control in adults showed glycerol phenylbutyrate was noninferior to sodium phenylbutyrate. In a separate study involving young children ages 2 months through 5 years, glycerol phenylbutyrate resulted in a more evenly distributed urinary output of PAGN over 24 hours and accounted for fewer symptoms from accumulation of phenylacetate.

In patients with an extremely high blood ammonia level, rapid treatment with hemodialysis is indicated.

Metabolic disease specialists should provide long-term care with very close and frequent follow-up.

Onset of adult GM1 is between ages 3 and 30.

Symptoms include muscle atrophy, neurological complications that are less severe and progress at a slower rate than in other forms of the disorder, corneal clouding in some patients, and dystonia (sustained muscle contractions that cause twisting and repetitive movements or abnormal postures). Angiokeratomas may develop on the lower part of the trunk of the body. Most patients have a normal size liver and spleen.

Prenatal diagnosis is possible by measurement of Acid Beta Galactosidase in cultured amniotic cells.

An absolute neutrophil count (ANC) chronically less than 500/mm3, usually less than 200/mm3, is the main sign of Kostmann's. Other elements include the severity of neutropenia, the chronology (from birth; not emerging later), and other normal findings (hemoglobin, platelets, general body health). Isolated neutropenia in infants can occur in viral infections, autoimmune neutropenia of infancy, bone marrow suppression from a drug or toxin, hypersplenism, and passive placental transfer of maternal IgG.

A bone marrow test can assist in diagnosis. The bone marrow usually shows early granulocyte precursors, but myelopoietic development stops ("arrests") at the promyelocyte and/or myelocyte stage, so that few maturing forms are seen. Neutrophil survival is normal.

Needs mention of (rarer) myelokathexis types. e.g. G6PC3 variant and

One Finnish study which followed 25 cases from 18 families found that half the infants died within 3 days of birth and the other half died before 4 months of age.

The disorder is characterized by absence or underdevelopment of the cerebellar vermis and a malformed brain stem (molar tooth sign), both of which can be visualized on a MRI scan. Together with this sign, the diagnosis is based on the physical symptoms and genetic testing for mutations. If the gene mutations have been identified in a family member, prenatal or carrier diagnosis can be pursued.

Joubert Syndrome is known to affect 1 in 80,000-100,000 newborns. Due to the variety of genes this disorder is affected by, it is likely to be under-diagnosed. It is commonly found in Ashkenazi Jewish, French-Canadians, and Hutterite ethnic populations. Most cases of Joubert syndrome are autosomal recessive - in these cases, both parents are either carriers or affected. Rarely, Joubert syndrome is inherited in an X-linked recessive pattern. In these cases, males are more commonly affected because affected males must have one X chromosome mutated, while affected females must have mutated genes on both X chromosomes.

Currently there are no open research studies for otodental syndrome. Due to the rarity of this disease, current research is very limited.

The most recent research has involved case studies of the affected individuals and/or families, all of which show the specific phenotypic symptoms of otodental syndrome. Investigations on the effects of FGF3 and FADD have also been performed. These studies have shown successes in supporting previous studies that mutations to FGF3 and neighboring genes may cause the associated phenotypic abnormalities. According to recent studies involving zebrafish embryos, there is also support in that the FADD gene contributed to ocular coloboma symptoms as well.

Future research studies are required in order to better grasp the specific relationship between the gene involved and its effect on various tissues and organs such as teeth, eyes, and ear. Little is known and there is still much to be determined.

Hyperlysinemia is an autosomal recessive metabolic disorder characterized by an abnormal increase of lysine in the blood, but appears to be benign. It is caused by mutations in "AASS", which encodes α-aminoadipic semialdehyde synthase.

Hyperlysinemia is associated with ectopia lentis (a displacement or malposition of the eye's crystalline lens) in humans.

Cystinosis is normally treated with cysteamine, which is available in capsules and in eye drops. People with cystinosis are also often given sodium citrate to treat the blood acidosis, as well as potassium and phosphorus supplements. If the kidneys become significantly impaired or fail, then treatment must be begun to ensure continued survival, up to and including renal transplantation.

GRACILE syndrome is a very rare autosomal recessive genetic disorder, one of the Finnish heritage diseases. It is caused by mutation in BCS1L gene that occurs in at least 1 out of 47,000 live births in Finnish people.

GRACILE is an acronym for growth retardation, amino aciduria (amino acids in the urine), cholestasis, iron overload, lactic acidosis, and early death. Other names for this syndrome include Finnish lethal neonatal metabolic syndrome (FLNMS); lactic acidosis, Finnish, with hepatic hemosiderosis; and Fellman syndrome.

Gitelman syndrome is estimated to have a prevalence of 1 in 40,000 people.

Onset of late infantile GM1 is typically between ages 1 and 3 years.

Neurological symptoms include ataxia, seizures, dementia, and difficulties with speech.

Most asymptomatic individuals with Gitelman syndrome can be monitored without medical treatment. Potassium and magnesium supplementation to normalize low blood levels of potassium and magnesium is the mainstay of treatment. Large doses of potassium and magnesium are often necessary to adequately replace the electrolytes lost in the urine. Diarrhea is a common side effect of oral magnesium which can make oral replacement difficult but dividing the dose to 3-4 times a day is better tolerated. Severe deficits of potassium and magnesium require intravenous replacement. If low blood potassium levels are not sufficiently replaced with oral replacement, aldosterone antagonists (such as spironolactone or eplerenone) or epithelial sodium channel blockers such as amiloride can be used to decrease urinary wasting of potassium.

Regular administration of exogenous granulocyte colony-stimulating factor (filgrastim) clinically improves neutrophil counts and immune function and is the mainstay of therapy, although this may increase risk for myelofibrosis and acute myeloid leukemia in the long term.

Over 90% of SCN responds to treatment with granulocyte colony-stimulating factor (filgrastim), which has significantly improved survival.

The only treatment for MWS is only symptomatic, with multidisciplinary management

There are five known subgroups of MGA; MGA type I,II,III,IV & V.

The characteristic features of 3-methylglutaconic aciduria type I include speech delay, delayed development of both mental and motor skills (psychomotor delay), elevated levels of acid in the blood and tissues (metabolic acidosis), abnormal muscle tone (dystonia), and spasms and weakness affecting the arms and legs (spastic quadriparesis). Fewer than 20 cases of 3-methylglutaconic aciduria type I have been reported.

Barth syndrome is a common name for 3-methylglutaconic aciduria type II. The main features of Barth syndrome include a weakened and enlarged heart (dilated cardiomyopathy), recurrent infections due to low numbers of white blood cells (neutropenia), skeletal problems, and delayed growth. The incidence of 3-methylglutaconic aciduria type II is approximately 1 in 200,000 male infants.

Costeff optic atrophy syndrome is another name for 3-methylglutaconic aciduria type III. This disorder is characterized mainly by the degeneration of the optic nerves, which carry information from the eyes to the brain. Sometimes other nervous system problems occur, such as an inability to maintain posture, poor muscle tone, the development of certain involuntary movements (extrapyramidal dysfunction), and a general decrease in brain function (cognitive deficit). The incidence of 3-methylglutaconic aciduria type III is about 1 in 10,000 newborns in the Iraqi Jewish population. This disorder is extremely rare in all other populations.

The signs and symptoms of 3-methylglutaconic aciduria type IV are variable and overlap with types I-III. The incidence of 3-methylglutaconic aciduria type IV is unknown.