There is no treatment for NBS, however in those with agammaglobulinemia, intravenous immunoglobulin may be started. Prophylactic antibiotics are considered to prevent urinary tract infections as those with NBS often have congenital kidney malformations. In the treat of malignancies radiation, alkylating antineoplastic agents, and epipodophyllotoxins are not used, and methotrexate can be used with caution and, the dose should be limited. Bone marrow transplants and hematopoietic stem cells transplants are also considered in the treatment of NBS. The supplementation of Vitamin E is also recommended. A ventriculoperitoneal shunt can be placed in patients with hydrocephaly, and surgical intervention of congenital deformities is also attempted.

There is no treatment known to slow or stop the progression of the neurologic problems. Treatment of A-T is symptomatic and supportive. Physical, occupational and speech therapies and exercise may help maintain function but will not slow the course of neurodegeneration. Therapeutic exercises should not be used to the point of fatigue and should not interfere with activities of daily life. Certain anti-Parkinson and anti-epileptic drugs maybe useful in the management of symptoms, but should be prescribed in consultation with a neurologist.

Recurrent sinus and lung infections can lead to the development of chronic lung disease. Such infections should be treated with appropriate antibiotics to prevent and limit lung injury. Administration of antibiotics should be considered when children and adults have prolonged respiratory symptoms (greater than 7 days), even following what was presumed to have been a viral infection. To help prevent respiratory illnesses from common respiratory pathogens, annual influenza vaccinations should be given and pneumococcal vaccines should be administered when appropriate. Antibiotic treatment should also be considered in children with chronic coughs that are productive of mucous, those who do not respond to aggressive pulmonary clearance techniques and in children with muco-purulent secretions from the sinuses or chest. A wet cough can also be associated with chronic aspiration which should be ruled out through proper diagnostic studies, however aspiration and respiratory infections are not necessarily exclusive of each other. In children and adults with bronchiectasis, chronic antibiotic therapy should be considered to slow chronic lung disease progression.

Culturing of the sinuses may be needed to direct antibiotic therapy. This can be done by an Ear Nose and Throat (ENT) specialist. In addition, diagnostic bronchoscopy may be necessary in people who have recurrent pneumonias, especially those who do not respond or respond incompletely to a course of antibiotics.

Clearance of bronchial secretions is essential for good pulmonary health and can help limit injury from acute and chronic lung infections. Children and adults with increased bronchial secretions can benefit from routine chest therapy using the manual method, an a cappella device or a chest physiotherapy vest. Chest physiotherapy can help bring up mucous from the lower bronchial tree, however an adequate cough is needed to remove secretions. In people who have decreased lung reserve and a weak cough, use of an insufflator-exsufflator (cough-assist) device may be useful as a maintenance therapy or during acute respiratory illnesses to help remove bronchial secretions from the upper airways. Evaluation by a Pulmonology specialist however, should first be done to properly assess patient suitability.

Children and adults with chronic dry cough, increased work of breathing (fast respiratory rate, shortness of breath at rest or with activities) and absence of an infectious process to explain respiratory symptoms should be evaluated for interstitial lung disease or another intrapulmonary process. Evaluation by a Pulmonologist and a CT scan of the chest should be considered in individuals with symptoms of interstitial lung disease or to rule other non-infectious pulmonary processes. People diagnosed with interstitial lung disease may benefit from systemic steroids.

There is no broadly accepted standard of care for infants with DG. Some healthcare providers recommend partial to complete dietary restriction of milk and other high galactose foods for infants or young children with DG; others do not. Because children with DG develop increased tolerance for dietary galactose as they grow, few healthcare providers recommend dietary restriction of lactose or galactose beyond early childhood.

The rationale for NOT restricting dietary galactose exposure of infants and/or young children with DG: Healthcare providers who do not recommend dietary restriction of galactose for infants with DG generally consider DG to be of no clinical significance—meaning most infants and children with DG seem to be doing clinically well. Further, these providers may be opposed to interrupting or reducing breastfeeding when there is no clear evidence it is contraindicated. These providers may argue that the recognized health benefits of breastfeeding outweigh the potential risks of as yet unknown negative effects of continued milk exposure for these infants. For infants with DG who continue to drink milk, some doctors would recommend that blood galactose-1-phosphate (Gal-1P) or urinary galactitol be rechecked by age 12 months to ensure that these metabolite levels are normalizing.

The rationale FOR restricting dietary galactose exposure of infants and/or young children with DG: Healthcare providers who recommend partial or complete dietary restriction of galactose for infants and/or young children with DG generally cite concern about the unknown long-term consequences of abnormally elevated galactose metabolites in a young child's blood and tissues. Infants with DG who continue to drink milk accumulate the same set of abnormal galactose metabolites seen in babies with classic galactosemia – e.g. galactose, Gal-1P, galactonate, and galactitol – but to a lesser extent. While it remains unclear whether any of these metabolites contribute to the long-term developmental complications experienced by so many older children with classic galactosemia, the possibility that they might cause problems serves to motivate some healthcare providers to recommend dietary galactose restriction for infants with DG. Switching an infant with DG from milk or milk formula (high galactose) to soy formula (low galactose) rapidly normalizes their galactose metabolites. This approach is considered potentially preventative rather than responsive to acute symptoms.

If dietary galactose restriction of any kind is followed, healthcare providers may recommend that the child have a galactose challenge to re-evaluate galactose tolerance before the restrictive diet is discontinued. Most infants or young children with DG who are followed by a metabolic specialist are discharged from follow up after a successful galactose challenge.Options for those choosing to restrict dietary galactose in infancy and/or early childhood: Dietary restriction practices for Duarte galactosemia vary widely. In the US, some healthcare providers recommend full dietary restriction of milk and all dairy products for the first 12 months of life, followed by a galactose challenge. Some providers recommend the galactose challenge before 12 months, others after. Some providers who recommend dietary intervention suggest a "compromise approach" if the parent wishes to breastfeed, such that the parent alternates feedings of breast milk and low galactose formula. Finally, some parents choose to continue some form of dietary galactose restriction for their child with DG beyond early childhood.

What is a galactose challenge? The goal of a galactose challenge is to learn whether a child is able to metabolize dietary galactose sufficiently to prevent the abnormal accumulation of galactose metabolites, generally measured as Gal-1P in the blood. For infants with DG who showed elevated galactose metabolites at diagnosis, this test can be used to see if their ability to process galactose has improved enough to discontinue dietary galactose restriction.

To test galactose metabolism, a baseline Gal-1P level is measured while the child is on a galactose-restricted diet. If the level is within the normal range (e.g. <1.0 mg/dL), the parent/guardian is advised to "challenge" the child with dietary galactose—meaning feed the child a diet that includes normal levels of milk for 2–4 weeks. Immediately after that time, another blood sample is collected and analyzed for Gal-1P level. If this second result is still in the normal range, the child is said to have "passed" their galactose challenge, and dietary galactose restrictions are typically relaxed or discontinued. If the second test shows elevated Gal-1P levels, the parent/guardian may be advised to resume galactose restriction for the child, and the "challenge" may be repeated after a few months.

The only treatment for classic galactosemia is eliminating lactose and galactose from the diet. Even with an early diagnosis and a restricted diet, however, some individuals with galactosemia experience long-term complications such as speech difficulties, learning disabilities, neurological impairment (e.g. tremors, etc.), and ovarian failure. Symptoms have not been associated with Duarte galactosemia, and many individuals with Duarte galactosemia do not need to restrict their diet at all. However, research corroborates a previously overlooked theory that Duarte galactosemia may lead to language developmental issues in children with no clinical symptoms. Infants with classic galactosemia cannot be breast-fed due to lactose in human breast milk and are usually fed a soy-based formula.

Galactosemia is sometimes confused with lactose intolerance, but galactosemia is a more serious condition. Lactose intolerant individuals have an acquired or inherited shortage of the enzyme lactase, and experience abdominal pains after ingesting dairy products, but no long-term effects. In contrast, a galactosemic individual who consumes galactose can cause permanent damage to their bodies.

Long term complication of galactosemia includes:

- Speech deficits

- Ataxia

- Dysmetria

- Diminished bone density

- Premature ovarian failure

- Cataract

A review from 2000 stated that life expectancy was reduced because of a tendency to develop cancer relatively early as well as deaths due to infections related to immunodeficiency.

LIG4 syndrome (also known as Ligase IV syndrome) is an extremely rare condition caused by mutations in the DNA Ligase IV (LIG4) gene. Some mutations in this gene are associated with a resistance against multiple myeloma and Severe Combined Immunodeficiency. Severity of symptoms depends on the degree of reduced enzymatic activity of Ligase IV or gene expression.

As DNA ligase IV is essential in V(D)J recombination, the mechanism by which immunoglobulins, B cell and T cell receptors are formed, patients with LIG4 syndrome may suffer from less effective or defective V(D)J recombination. Some patients have a severe immunodeficiency characterized by pancytopenia, causing chronic respiratory infections and sinusitis. Clinical features also include Seckel syndrome-like facial abnormalities and microcephaly. Patients also suffer from growth retardation and skin conditions, including photosensitivity, psoriasis and telangiectasia. Although not present in all, patients may also present with hypothyroidism and type II diabetes and possibly malignancies such as acute T-cell leukemia. The clinical phenotype of LIG4 syndrome closely resembles that of Nijmegen breakage syndrome (NBS).

Very little is known about outcomes in DG after early childhood. This is because many infants with DG are born in states where they are not diagnosed by NBS, and of those who are diagnosed, most are discharged from metabolic follow-up as toddlers.

Because it is unclear whether DG has any long-term developmental impacts, or if diet modification would prevent or resolve any issues that may result from DG, any developmental or psychosocial problems experienced by a person with DG should be treated symptomatically and the possibility of other causes should be explored.

Of note, premature ovarian insufficiency, a common outcome among girls and women with classic galactosemia, has been checked by hormone studies and does not appear to occur at high prevalence among girls with DG.

Prior Research Concerning Developmental Outcomes of Children with DG: Three

studies of developmental outcomes of children with DG have been published.

- The first looked at biochemical markers and developmental outcomes in a group of 28 toddlers and young children with DG, some of whom had drunk milk through infancy and some of whom had drunk soy formula. The authors found that galactose metabolites were significantly elevated in the infants drinking milk over those drinking soy. However, all of the children scored within normal limits on standardized tests of child development.

- A second study of developmental outcomes in DG looked at 3 to 10 year olds living in a large metropolitan area and asked whether children diagnosed as newborns with DG in this group were more likely than their unaffected peers to receive special educational services later in childhood. The answer was yes. Specifically, children with DG in this group were significantly more likely than other children to receive a diagnosis of, or special educational services for, a speech/language disorder.

- The final study reported that addressed developmental outcomes in DG was a pilot study involving direct assessments of 15 children, all ages 6–11 years old; 15 had DG and 5 did not. Children in the DG group showed slower auditory processing than did the control group. The DG group also showed some slight differences in auditory memory, receptive language/ listening skills, social-emotional functioning, and balance and fine motor coordination.

Combined,

these studies "suggest" that school age

children with DG "might" be at

increased risk for specific developmental difficulties compared with controls. All

of the relevant studies were limited, however, leaving the question of whether

children with DG are truly at increased risk for developmental difficulties

unresolved. Current reports also leave open the question of whether dietary

exposure to milk in infancy associates with developmental outcomes in DG. More

research is needed to answer these questions.

Galactose is converted into glucose by the action of three enzymes, known as the Leloir pathway. There are diseases associated with deficiencies of each of these three enzymes:

There is considerable research into the causes, diagnosis and treatments for FGIDs. Diet, microbiome, genetics, neuromuscular function and immunological response all interact. Heightened mast cell activation has been proposed to be a common factor among FGIDs, contributing to visceral hypersensitivity as well as epithelial, neuromuscular, and motility dysfunction.

Functional gastrointestinal disorders (FGID) include a number of separate idiopathic disorders which affect different parts of the gastrointestinal tract and involve visceral hypersensitivity and impaired gastrointestinal motility.