Some of the childhood management issues are similar those of 21-hydroxylase deficiency:

- Replacing mineralocorticoid with fludrocortisone

- Suppressing DHEA and replacing cortisol with glucocorticoid

- Providing extra glucocorticoid for stress

- Close monitoring and perhaps other adjunctive measures to optimize growth

- Deciding whether surgical repair of virilized female genitalia is warranted

However, unlike 21-hydroxylase CAH, children with 3β-HSD CAH may be unable to produce adequate amounts of testosterone (boys) or estradiol (girls) to effect normal pubertal changes. Replacement testosterone or estrogen and progesterone can be initiated at adolescence and continued throughout adult life. Fertility may be impaired by the difficulty of providing appropriate sex hormone levels in the gonads even though the basic anatomy is present.

Since CAH is an autosomal recessive disease, most children with CAH are born to parents unaware of the risk and with no family history. Each child will have a 25% chance of being born with the disease. Families typically wish to minimize the degree of virilization of a girl. There is no known prenatal harm to a male fetus from CAH, so treatment can begin at birth.

Adrenal glands of female fetuses with CAH begin producing excess testosterone by the 9th week of gestation. The most important aspects of virilization (urogenital closure and phallic urethra) occur between 8 and 12 weeks. Theoretically, if enough glucocorticoid could be supplied to the fetus to reduce adrenal testosterone production by the 9th week, virilization could be prevented and the difficult decision about timing of surgery avoided.

The challenge of preventing severe virilization of girls is twofold: detection of CAH at the beginning of the pregnancy, and delivery of an effective amount of glucocorticoid to the fetus without causing harm to the mother.

The first problem has not yet been entirely solved, but it has been shown that if dexamethasone is taken by a pregnant woman, enough can cross the placenta to suppress fetal adrenal function.

At present no program screens for risk in families who have not yet had a child with CAH. For families desiring to avoid virilization of a second child, the current strategy is to start dexamethasone as soon as a pregnancy has been confirmed even though at that point the chance that the pregnancy is a girl with CAH is only 12.5%. Dexamethasone is taken by the mother each day until it can be safely determined whether she is carrying an affected girl.

Whether the fetus is an affected girl can be determined by chorionic villus sampling at 9–11 weeks of gestation, or by amniocentesis at 15–18 weeks gestation. In each case the fetal sex can be determined quickly, and if the fetus is a male the dexamethasone can be discontinued. If female, fetal DNA is analyzed to see if she carries one of the known abnormal alleles of the "CYP21" gene. If so, dexamethasone is continued for the remainder of the pregnancy at a dose of about 1 mg daily.

Most mothers who have followed this treatment plan have experienced at least mild cushingoid effects from the glucocorticoid but have borne daughters whose genitalia are much less virilized.

Even after diagnosis and initiation of treatment, a small percentage of children and adults with infancy or childhood onset CAH die of adrenal crisis. Deaths from this are entirely avoidable if the child and family understand that the daily glucocorticoids cannot be allowed to be interrupted by an illness. When a person is well, missing a dose, or even several doses, may produce little in the way of immediate symptoms. However, glucocorticoid needs are increased during illness and stress, and missed doses during an illness such as the "flu" (or viral gastroenteritis) can lead within hours to reduced blood pressure, shock, and death.

To prevent this, all persons taking replacement glucocorticoids are taught to increase their doses in the event of illness, surgery, severe injury, or severe exhaustion. More importantly, they are taught that vomiting warrants an injection within hours of hydrocortisone (e.g., SoluCortef) or other glucocorticoid. This recommendation applies to both children and adults. Because young children are more susceptible to vomiting illnesses than adults, pediatric endocrinologists usually teach parents how to give hydrocortisone injections.

As an additional precaution, persons with adrenal insufficiency are advised to wear a medical identification tag or carry a wallet card to alert those who may be providing emergency medical care of the urgent need for glucocorticoids.

Congenital adrenal hyperplasia due to 3β-hydroxysteroid dehydrogenase deficiency is an uncommon form of congenital adrenal hyperplasia (CAH) resulting from a mutation in the gene for one of the key enzymes in cortisol synthesis by the adrenal gland, 3β-hydroxysteroid dehydrogenase (3β-HSD) type II (HSD3B2). As a result, higher levels of 17OH-pregnenolone appear in the blood with adrenocorticotropic hormone (ACTH) challenge, which stimulates adrenal corticosteroid synthesis.

There is a wide spectrum of clinical presentations of 3β-HSD CAH, from mild to severe forms. The uncommon severe form results from a complete loss of enzymatic activity and manifests itself in infancy as salt wasting due to the loss of mineralocorticoids. Milder forms resulting from incomplete loss of 3β-HSD type II function do not present with adrenal crisis, but can still produce virilization of genetically female infants and undervirilization of genetically male infants. As a result, this form of primary hypoadrenalism is the only form of CAH that can cause ambiguous genitalia in both genetic sexes.

There is some evidence that zinc may have an effect on cancer and further study is recommended.

Five interventional strategies can be used:

- Adding zinc to soil, called agronomic biofortification, which both increases crop yields and provides more dietary zinc.

- Adding zinc to food, called fortification.

- Adding zinc rich foods to diet. The foods with the highest concentration of zinc are proteins, especially animal meats, the highest being oysters. Per ounce, beef, pork, and lamb contain more zinc than fish. The dark meat of a chicken has more zinc than the light meat. Other good sources of zinc are nuts, whole grains, legumes, and yeast. Although whole grains and cereals are high in zinc, they also contain chelating phytates which bind zinc and reduce its bioavailability.

- Oral repletion via tablets (e.g. zinc gluconate) or liquid (e.g. zinc acetate). Oral zinc supplementation in healthy infants more than six months old has been shown to reduce the duration of any subsequent diarrheal episodes by about 11 hours.

- Oral repletion via multivitamin/mineral supplements containing zinc gluconate, sulfate, or acetate. It is not clear whether one form is better than another. Zinc is also found in some cold lozenges, nasal sprays, and nasal gels.

No treatment is available for most of these disorders. Mannose supplementation relieves the symptoms in PMI-CDG (CDG-Ib) for the most part, even though the hepatic fibrosis may persist. Fucose supplementation has had a partial effect on some SLC35C1-CDG (CDG-IIc or LAD-II) patients.

As with other forms of CAH, the primary therapy of 11β-hydroxylase deficient CAH is lifelong glucocorticoid replacement in sufficient doses to prevent adrenal insufficiency and suppress excess mineralocorticoid and androgen production.

Salt-wasting in infancy responds to intravenous saline, dextrose, and high dose hydrocortisone, but prolonged fludrocortisone replacement is usually not necessary. The hypertension is ameliorated by glucocorticoid suppression of DOC.

Long term glucocorticoid replacement issues are similar to those of 21-hydroxylase CAH, and involve careful balance between doses sufficient to suppress androgens while avoiding suppression of growth. Because the enzyme defect does not affect sex steroid synthesis, gonadal function at puberty and long-term fertility should be normal if adrenal androgen production is controlled. See congenital adrenal hyperplasia for a more detailed discussion of androgen suppression and fertility potential in adolescent and adult women.

Iodine deficiency is treated by ingestion of iodine salts, such as found in food supplements. Mild cases may be treated by using iodized salt in daily food consumption, or drinking more milk, or eating egg yolks, and saltwater fish. For a salt and/or animal product restricted diet, sea vegetables (kelp, hijiki, dulse, nori (found in sushi)) may be incorporated regularly into a diet as a good source of iodine.

The recommended daily intake of iodine for adult women is 150–300 µg for maintenance of normal thyroid function; for men it is somewhat less at 150 µg.

However, too high iodine intake, for example due to overdosage of iodine supplements, can have toxic side effects. It can lead to hyperthyroidism and consequently high blood levels of thyroid hormones (hyperthyroxinemia). In case of extremely high single-dose iodine intake, typically a short-term suppression of thyroid function (Wolff–Chaikoff effect) occurs. Persons with pre-existing thyroid disease, elderly persons, fetuses and neonates, and patients with other risk factors are at a higher risk of experiencing iodine-induced thyroid abnormalities. In particular, in persons with goiter due to iodine deficiency or with altered thyroid function, a form of hyperthyroidism called Jod-Basedow phenomenon can be triggered even at small or single iodine dosages, for example as a side effect of administration of iodine-containing contrast agents. In some cases, excessive iodine contributes to a risk of autoimmune thyroid diseases (Hashimoto's thyroiditis and Graves' disease).

At this time there is no treatment for transaldolase deficiency.

There is currently research being done to find treatments for transaldolase deficiency. A study done in 2009 used orally administered N-acetylcysteine on transaldolase deficient mice and it prevented the symptoms associated with the disease. N-acetylcysteine is a precursor for reduced glutathione, which is decreased in transaldolase deficient patients.

In view of large-scale epidemiological studies of iodine levels in populations, a method of capillary electrophoresis with UV detection of iodine has been proposed.

Persons with the genotype for PKU are unaffected in utero, because maternal circulation prevents buildup of [phe]. After birth, PKU in newborns is treated by a special diet with highly restricted phenylalanine content. Persons with genetic predisposition to PKU have normal mental development on this diet. Previously, it was thought safe to withdraw from the diet in the late teens or early twenties, after the central nervous system was fully developed; recent studies suggest some degree of relapse, and a continued phenylalanine-restricted diet is now recommended.

PKU or hyperphenylalaninemia may also occur in persons without the PKU genotype. If the mother has the PKU genotype but has been treated so as to be asymptomatic, high levels of [phe] in the maternal blood circulation may affect the non-PKU fetus during gestation. Mothers successfully treated for PKU are advised to return to the [phe]-restricted diet during pregnancy.

A small subset of patients with hyperphenylalaninemia shows an appropriate reduction in plasma phenylalanine levels with dietary restriction of this amino acid; however, these patients still develop progressive neurologic symptoms and seizures and usually die within the first 2 years of life ("malignant" hyperphenylalaninemia). These infants exhibit normal phenylalanine hydroxylase (PAH) enzymatic activity but have a deficiency in dihydropteridine reductase (DHPR), an enzyme required for the regeneration of tetrahydrobiopterin (THB or BH), a cofactor of PAH.

Less frequently, DHPR activity is normal but a defect in the biosynthesis of THB exists. In either case, dietary therapy corrects the hyperphenylalaninemia. However, THB is also a cofactor for two other hydroxylation reactions required in the syntheses of neurotransmitters in the brain: the hydroxylation of tryptophan to 5-hydroxytryptophan and of tyrosine to L-dopa. It has been suggested that the resulting deficit in the CNS neurotransmitter activity is, at least in part, responsible for the neurologic manifestations and eventual death of these patients.

Transaldolase deficiency is recognized as a rare inherited pleiotropic metabolic disorder first recognized and described in 2001 that is autosomal recessive. There have been only a few cases that have been noted, as of 2012 there have been 9 patients recognized with this disease and one fetus.

There is no known cure or treatment for the disorder.

The metabolic and clinical manifestations of TMAU are generally regarded as benign, as there is no associated organ dysfunction. This

designation, and the fact that the condition is often unrecognised by doctors, can have important ramifications including missed or delayed diagnosis.

Affected individuals experience shame and embarrassment, fail to maintain relationships, avoid contact with people who comment on their condition, and are obsessive about masking the odour with hygiene products and even smoking. The malodorous aspect can have serious and destructive effects on schooling, personal life, career and relationships, resulting in social isolation, low self-esteem, depression, paranoid behaviour, and suicide. Delayed diagnosis, body odour and the lack of cure may lead to psychosocial issues. When the condition is suspected or known to occur in a family, genetic testing can be helpful in identifying the specific individuals who have or carry the disorder.

Ways of reducing the fishy odor may include:

- Avoiding foods such as egg yolks, legumes, red meats, fish, beans and other foods that contain choline, carnitine, nitrogen, sulfur and lecithin

- Taking low doses of antibiotics such as neomycin and metronidazole in order to reduce the amount of bacteria in the gut

- Using slightly acidic detergent with a pH between 5.5 and 6.5

Additionally, at least one study has suggested that daily intake of the supplements activated charcoal and copper chlorophyllin may improve the quality of life of individuals afflicted with TMAU by helping their bodies to oxidize and convert TMA to the odorless "N"-oxide (TMAO) metabolite. Study participants experienced subjective reduction in odor as well as objective reduction in TMA and increase in TMAO concentration measured in their urine. The study found that:

- 85% of test participants experienced complete loss of detectable "fishy" odor

- 10% experienced some reduction in detectable odor

- 5% did not experience any detectable odor reduction

In the US, the Dietary Reference Intake for adults is 55 µg/day. In the UK it is 75 µg/day for adult males and 60 µg/day for adult females. 55 µg/day recommendation is based on full expression of plasma glutathione peroxidase. Selenoprotein P is a better indicator of selenium nutritional status, and full expression of it would require more than 66 µg/day.

Although there is currently no cure, treatment includes injections of structurally similar compound, N-Carbamoyl-L-glutamate, an analogue of N-Acetyl Glutamate. This analogue likewise activates CPS1. This treatment mitigates the intensity of the disorder.

If symptoms are detected early enough and the patient is injected with this compound, levels of severe mental retardation can be slightly lessened, but brain damage is irreversible.

Early symptoms include lethargy, vomiting, and deep coma.

Currently, there are no treatments available for JEB. However, the disorder can be prevented through good breeding management. Horses that are carriers of JEB should not be incorporated into breeding programs. Although, if breeders are insistent on breeding a carrier, precautions need to be taken to ensure that the other mate is not a carrier as well. Genetic testing for the disorder is highly recommended among breeding programs for the Draft horse and Saddlebred breeds to determine their carrier status.

Medications can interfere with folate utilization, including:

- anticonvulsant medications (such as phenytoin, primidone, carbamazepine or valproate )

- metformin (sometimes prescribed to control blood sugar in type 2 diabetes)

- methotrexate, an anti-cancer drug also used to control inflammation associated with Crohn's disease, ulcerative colitis and rheumatoid arthritis.

- sulfasalazine (used to control inflammation associated with Crohn's disease, ulcerative colitis and rheumatoid arthritis)

- triamterene (a diuretic)

- birth control pills

When methotrexate is prescribed, folic acid supplements are sometimes given with the methotrexate. The therapeutic effects of methotrexate are due to its inhibition of dihydrofolate reductase and thereby reduce the rate "de novo" purine and pyrimidine synthesis and cell division. Methotrexate inhibits cell division and is particularly toxic to fast dividing cells, such as rapidly dividing cancer cells and the progenitor cells of the immune system. Folate supplementation is beneficial in patients being treated with long-term, low-dose methotrexate for inflammatory conditions, such as rheumatoid arthritis (RA) or psoriasis, to avoid macrocytic anemia caused by folate deficiency. Folate is often also supplemented before some high dose chemotherapy treatments in an effort to protect healthy tissue. However, it may be counterproductive to take a folic acid supplement with methotrexate in cancer treatment.

Folate is found in leafy green vegetables. Multi-vitamins also tend to include Folate as well as many other B vitamins. B vitamins, such as Folate, are water-soluble and excess is excreted in the urine.

When cooking, use of steaming, a food steamer, or a microwave oven can help keep more folate content in the cooked foods, thus helping to prevent folate deficiency.

Folate deficiency during human pregnancy has been associated with an increased risk of infant neural tube defects. Such deficiency during the first four weeks of gestation can result in structural and developmental problems. NIH guidelines recommend oral B vitamin supplements to decrease these risks near the time of conception and during the first month of pregnancy.

A great deal of research has been conducted to understand whether low levels of vitamin D may cause or be a result of other conditions.

Some evidence suggests hypovitaminosis D may be associated with a worse outcome for some cancers, but evidence is insufficient to recommend that vitamin D be prescribed for people with cancer. Taking vitamin D supplements has no significant effect on cancer risk. Vitamin D, however, appears to decrease the risk of death from cancer but concerns with the quality of the data exist.

Vitamin D deficiency is thought to play a role in the pathogenesis of non-alcoholic fatty liver disease.

Some studies have indicated that vitamin D deficiency may play a role in immunity. Those with vitamin D deficiency may have trouble fighting off certain types of infections. It has also been thought to correlated with cardiovascular disease, type 1 diabetes, type 2 diabetes, and some cancers.

The life expectancy of patients with homocystinuria is reduced only if untreated. It is known that before the age of 30, almost one quarter of patients die as a result of thrombotic complications (e.g., heart attack).

These diseases are most common in certain parts of China where the intake is low because the soil is extremely deficient in selenium. Studies in Jiangsu Province of China have indicated a reduction in the prevalence of these diseases by taking selenium supplements. In Finland, selenium salts are added to chemical fertilizers, as a way to increase selenium in soils. Dietary supplements may utilize sodium selenite, L-selenomethionine or selenium-enriched yeast.

Oral phosphate, 9, calcitriol, 9; in the event of severe bowing, an osteotomy may be performed to correct the leg shape.

Low-protein food is recommended for this disorder, which requires food products low in particular types of amino acids (e.g., methionine).

Trimethylaminuria (TMAU; primary trimethylaminuria), also known as fish odor syndrome or fish malodor syndrome, is a rare metabolic disorder that causes a defect in the normal production of an enzyme named flavin-containing monooxygenase 3 ("FMO3"). When "FMO3" is not working correctly or if not enough enzyme is produced, the body loses the ability to properly convert trimethylamine (TMA) from precursor compounds in food digestion into trimethylamine oxide (TMAO), through a process called "N"-oxidation. Trimethylamine then builds up and is released in the person's sweat, urine, and breath, giving off a strong fishy odor or strong body odor. A variant of TMAU (secondary trimethylaminuria or TMAU2) exists where there is no genetic cause, yet excessive TMA is secreted, possibly due to intestinal dysbiosis, altered metabolism, or hormonal causes.