Currently there is no specific treatment for this condition. Management is supportive.

Due to the nature of the illness, and absence of a really efficient treatment, it is important to emphasize the need for extensive palliative treatment against the diverse symptoms. Their objective is to reduce the effects of the deterioration of many bodily functions. In light of the diversity of symptoms, it is quite common to use a wide spectrum of palliative strategies where surgery and therapies are often pivotal.

There is no cure for this syndrome. Treatment is supportive and symptomatic. All children with Mowat–Wilson syndrome required early intervention with speech therapy, occupational therapy and physical therapy.

For a long time, the most efficient approach had been to use bone marrow graft, or hematopoietic stem cell transplantation. They each have the advantage of providing a new source of the missing I2S. However, the results have been considered imperfect at best.

While this treatment alternative is able to improve or stop the progression of some of the so-called "physical" symptoms, it does not prevent the eventual cognitive regression that occurs in Hunter syndrome patients who are cognitively affected, although it may slow such regression early on. Therefore, for attenuated patients, this may still serve as a viable treatment option because of its more permanent nature, possibly even equivalent to weekly enzyme replacement therapy, resulting in much improved life expectancy.

However, even for attenuated patients, it is a major intervention with significant mortality risks and potential for life-threatening or altering complications such as graft-versus-host disease. For cognitively affected patients, without solving the challenge of cognitive regression, at best it is limited as a permanent treatment alternative. Because of all these reasons, bone marrow grafts or hematopoietic stem cell transplantation have seen a decrease in their application as Hunter syndrome treatment.

There is currently no cure for GAPO syndrome, but some options are available to reduce the symptoms. Nearsightedness, which affects some sufferers of the disease, can be treated by corrective lenses. Unfortunately, optic atrophy as a result of degradation of the optic nerve (common with GAPO syndrome) cannot be corrected. Corticosteroids have been proposed as a treatment for optic nerve atrophy, but their effectiveness is disputed, and no steroid based treatments are currently available.

There is no known cure for Winchester syndrome; however, there are many therapies that can aid in the treatment of symptoms. Such treatments can include medications: anti-inflammatories, muscle relaxants, and antibiotics. Many individuals will require physical therapy to promote movement and use of the limbs affected by the syndrome. Genetic counseling is typically prescribed for families to help aid in the understanding of the disease. There are a few clinical trials available to participate in. The prognosis for patients diagnosed with Winchester syndrome is positive. It has been reported that several affected individuals have lived to middle age; however,the disease is progressive and mobility will become limited towards the end of life. Eventually, the contractures will remain even with medical intervention, such as surgery.

There is no cure available for Weaver syndrome. However, with multidisciplinary management such as neurological, pediatric, orthopedic, and psychomotor care and genetic counseling, symptoms can be managed. Surgery may be used to correct any skeletal issues. Physical and occupational therapy are considered an option to help with muscle tone. Also, speech therapy is often recommended for speech related problems.

In terms of the treatment for ativated PI3K delta syndrome, generally primary immunodeficiencies see the following used:

- Bacterial infection should be treated rapidly(with antibiotics)

- Antiviral therapy

- Modify lifestyle(exposure to pathogens need to be minimized)

There is no cure for Alström syndrome; however, there are treatment aims to reduce the symptoms and prevent further complications. Some of these treatment aims include:

- Corrective lenses: tinted lenses that help with the sensitivity from bright lights. The patients may have to adapt to reading in Braille, use adaptive equipment, mobility aids, and adaptive computing skills.

- Education: patients with Alström syndrome suffering from intellectual disabilities must have access to education. They must be able to receive free and appropriate education. Some Alström syndrome patients are educated in normal classrooms. Other patients have to take special education classes or attend to specialized schools that are prepared to teach children with disabilities. Staff members from schools have to consult with patient's parents or caregivers in order to design an education plan based on the child's needs. In addition, the school may document the progress of the child in order to confirm that the child's needs are being met.

- Hearing aids: the battery-operated devices are available in three styles: behind the ear, in the ear, and inside the ear canal. Behind the ear aims for mild-to-profound hearing loss. In the ear aims for mild to severe hearing loss. Lastly, the canal device is aimed for mild to moderately severe hearing loss. Patients that have severe hearing loss may benefit from a cochlear implant.

- Diet: an appropriate and healthy diet is necessary for individuals with Alström syndrome because it could potentially decreases chances of obesity or diabetes.

- Occupational therapy: the therapist helps the child learn skills to help him or her perform basic daily tasks like eating, getting dressed, and communicating with others.

- Physical Activity: exercising reduces chances of being obese and helping control blood sugar levels.

- Dialysis: helps restore filtering function. With hemodialysis, a patient's blood circulates into an external filter and clean. The filtered blood is then returned into the body. With peritoneal dialysis, fluid containing dextrose is introduced into the abdomen by a tube. The solution then absorbs the wastes into the body and is then removed.

- Transplantation: patients that endure a kidney failure may undergo a kidney transplantation.

- Surgery: if the patient endures severe scoliosis or kyphosis, surgery may be required.

Chloramphenicol therapy should be stopped immediately. Exchange transfusion may be required to remove the drug. Sometimes, phenobarbital (UGT induction) is used.

The condition can be prevented by using chloramphenicol at the recommended doses and monitoring blood levels, or alternatively, third generation cephalosporins can be effectively substituted for the drug, without the associated toxicity.

With appropriate treatment and management, patients with Weaver syndrome appear to do well, both physically and intellectually, throughout their life and have a normal lifespan. Their adult height is normal as well.

CGL patients have to maintain a strict diet for life, as their excess appetite will cause them to overeat. Carbohydrate intake should be restricted in these patients. To avoid chylomicronemia, CGL patients with hypertriglyceridemia need to have a diet very low in fat. CGL patients also need to avoid total proteins, trans fats, and eat high amounts of soluble fiber to avoid getting high levels of cholesterol in the blood.

Metformin is the main drug used for treatment, as it is normally used for patients with hyperglycemia. Metformin reduces appetite and improves symptoms of hepatic steatosis and polycystic ovary syndrome. Leptin can also be used to reverse insulin resistance and hepatic steatosis, to cause reduced food intake, and decrease blood glucose levels.

Until more molecular and clinical studies are performed there will be no way to prevent the disease. Treatments are directed towards alleviating the symptoms. To treat the disease it is crucial to diagnose it properly. Orthopedic therapy and fracture management are necessary to reduce the severity of symptoms. Bisphosphonate drugs are also an effective treatment.

The treatment of primary immunodeficiencies depends foremost on the nature of the abnormality. Somatic treatment of primarily genetic defects is in its infancy. Most treatment is therefore passive and palliative, and falls into two modalities: managing infections and boosting the immune system.

Reduction of exposure to pathogens may be recommended, and in many situations prophylactic antibiotics or antivirals may be advised.

In the case of humoral immune deficiency, immunoglobulin replacement therapy in the form of intravenous immunoglobulin (IVIG) or subcutaneous immunoglobulin (SCIG) may be available.

In cases of autoimmune disorders, immunosuppression therapies like corticosteroids may be prescribed.

Bone marrow transplant may be possible for Severe Combined Immune Deficiency and other severe immunodeficiences.

Virus-specific T-Lymphocytes (VST) therapy is used for patients who have received hematopoietic stem cell transplantation that has proven to be unsuccessful. It is a treatment that has been effective in preventing and treating viral infections after HSCT. VST therapy uses active donor T-cells that are isolated from alloreactive T-cells which have proven immunity against one or more viruses. Such donor T-cells often cause acute graft-versus-host disease (GVHD), a subject of ongoing investigation. VSTs have been produced primarily by ex-vivo cultures and by the expansion of T-lymphocytes after stimulation with viral antigens. This is carried out by using donor-derived antigen-presenting cells. These new methods have reduced culture time to 10–12 days by using specific cytokines from adult donors or virus-naive cord blood. This treatment is far quicker and with a substantially higher success rate than the 3–6 months it takes to carry out HSCT on a patient diagnosed with a primary immunodeficiency. T-lymphocyte therapies are still in the experimental stage; few are even in clinical trials, none have been FDA approved, and availability in clinical practice may be years or even a decade or more away.

Gianotti-Crosti disease is a harmless and self-limiting condition, so no treatment may be required. Treatment is mainly focused on controlling itching, symptomatic relief and to avoid any further complications. For symptomatic relief from itching, oral antihistamines or any soothing lotions like calamine lotion or zinc oxide may be used. If there are any associated conditions like streptococcal infections, antibiotics may be required.

Treatment is usually confined to such surgical intervention as may be necessary to help the child to develop e.g. jaw distraction/bone grafts, ocular dermoid debulking (see below), repairing cleft palate/lip, repairing heart malformations or spinal surgery. Some patients with Goldenhar syndrome will require assistance as they grow by means of hearing aids or glasses.

Stem cell grafting (womb tissue grafting) has been successfully used to "reprogram" eye dermoids, effectively halting the regrowth of eye dermoids.

These tissues that grow on the eye are "mis-programmed" cells (sometimes tooth or nail cells instead of eye cells).

1. Clinical Genetics and Genetic Testing

Genetic testing is necessary to confirm the diagnosis of PMS. A prototypical terminal deletion of 22q13 can be uncovered by karyotype analysis, but many terminal and interstitial deletions are too small to detect with this method. Chromosomal microarray should be ordered in children with suspected developmental delays or ASD. Most cases will be identified by microarray; however, small variations in genes might be missed. The falling cost for whole exome sequencing may replace DNA microarray technology for candidate gene evaluation. Biological parents should be tested with fluorescence "in situ" hybridization (FISH) to rule out balanced translocations or inversions. Balanced translocation in a parent increases the risk for recurrence and heritability within families (figure 3).

Clinical genetic evaluations and dysmorphology exams should be done to evaluate growth, pubertal development, dysmorphic features (table 1) and screen for organ defects (table 2)

2. Cognitive and Behavioral Assessment

All patients should undergo comprehensive developmental, cognitive and behavioral assessments by clinicians with experience in developmental disorders. Cognitive evaluation should be tailored for individuals with significant language and developmental delays. All patients should be referred for specialized speech/language, occupational and physical therapy evaluations.

3. Neurological Management

Individuals with PMS should be followed by a pediatric neurologist regularly to monitor motor development, coordination and gait, as well as conditions that might be associated with hypotonia. Head circumference should be performed routinely up until 36 months. Given the high rate of seizure disorders (up to 41% of patients) reported in the literature in patients with PMS and its overall negative impact on development, an overnight video EEG should be considered early to rule out seizure activity. In addition, a baseline structural brain MRI should be considered to rule out the presence of structural abnormalities.

4. Nephrology

All patients should have a baseline renal and bladder ultrasonography and a voiding cystourethrogram should be considered to rule out structural and functional abnormalities. Renal abnormalities are reported in up to 38% of patients with PMS. Vesicouretral reflux, hydronephrosis, renal agenesis, dysplasic kidney, polycystic kidney and recurrent urinary tract infections have all been reported in patients with PMS.

5. Cardiology

Congenital heart defects (CHD) are reported in samples of children with PMS with varying frequency (up to 25%)(29,36). The most common CHD include tricuspid valve regurgitation, atrial septal defects and patent ductus arteriousus. Cardiac evaluation, including echocardiography and electrocardiogram, should be considered.

6. Gastroenterology

Gastrointestinal symptoms are common in individuals with PMS. Gastroesophageal reflux, constipation, diarrhea and cyclic vomiting are frequently described.

Table 3: Clinical Assessment Recommendations in Phelan McDermid Syndrome.

Treatment is usually supportive treatment, that is, treatment to reduce any symptoms rather than to cure the condition.

- Enucleation of the odontogenic cysts can help, but new lesions, infections and jaw deformity are usually a result.

- The severity of the basal-cell carcinoma determines the prognosis for most patients. BCCs rarely cause gross disfigurement, disability or death .

- Genetic counseling

The first stage of treatment used to be a reversible colostomy. In this approach, the healthy end of the large intestine is cut and attached to an opening created on the front of the abdomen. The contents of the bowel are discharged through the hole in the abdomen and into a bag. Later, when the patient's weight, age, and condition are right, the "new" functional end of the bowel is connected with the anus. The first surgical treatment involving surgical resection followed by reanastomosis without a colostomy occurred as early as 1933 by Doctor Baird in Birmingham on a one-year-old boy.

Management often includes the use of beta blockers such as propranolol or if not tolerated calcium channel blockers or ACE inhibitors.

Since angiotensin II receptor antagonists (ARBs) also reduce TGF-β, these drugs have been tested in a small sample of young, severely affected people with Marfan syndrome. In some, the growth of the aorta was reduced. However, a recent study published in NEJM demonstrated similar cardiac outcomes between the ARB, losartan, and the more established beta blocker therapy, atenolol.

There is no known cure for microcephaly. Treatment is symptomatic and supportive.

Treatment of Hirschsprung's disease consists of surgical removal (resection) of the abnormal section of the colon, followed by reanastomosis.