**4. AT treatment**

Treatment of AT is symptomatic and supportive. As regards the neurological symptoms, no therapy can slow degeneration, but physical, occupational, and speech therapies as well as exercise may help maintain function. In some patients, certain anti-Parkinson and antiepileptic drugs may partially ameliorate symptoms. Commonly prescribed drugs include trihexyphenidyl (an antimuscarinic), amantadine (an antiparkinsonian) [144], baclofen (an antispastic), and botulinum toxin injections (a paralytic). Less commonly used drugs that may also be beneficial include gabapentin and pregabalin (an anticonvulsant), and clonazepam (a tranquilizer and antiseizure medication) [34, 145]. Also, glucocorticoids (especially betamethasone) have been reported to improve neurological symptoms in AT but corticosteroid side effects were quickly observed [146]. To avoid the characteristic side effects of longterm steroid administration, a method of monthly infusions of autologous erythrocytes loaded with dexamethasone has been developed (EryDex; EryDel, Urbino, Italy). Preliminary results are promising, with demonstrated efficacy in improving neurological status, especially in young patients with AT [147, 148].

Regular screening to assess lung function can detect early deterioration of lung function and allow earlier intervention. These interventions may include chest physiotherapy, a cough support device, and assistance to improve MCC. These interventions can be used daily as maintenance therapies. In some children with AT, with bronchial hyperresponsiveness, bronchodilators may benefit [57]. Children with chronic or recurrent sinopulmonary disease should be treated with antibiotics when appropriate, chest physiotherapy and airway clearance techniques to reduce the risk of developing bronchiectasis and chronic lung disease [57].

To maintain respiratory muscle strength and minimize the progression of lung disease, it is important to have adequate nutrition and maintain a normal body mass index. All people with AT should avoid secondhand smoke exposure and have minimal exposure to other environmental pollution. If lung disease develops, appropriate management should be considered: liberal use of antibiotics, antibiotic prophylaxis, corticosteroids, and immunoglobulin supplementation in those patients with AT who are immunocompromised [57, 62].

Recurrent lung infections may involve dysfunctional swallow (dysphagia) with aspiration, but some people with AT can be taught to drink, chew, and swallow more safely reducing the risk of aspiration [56]. Because the nutritional deficit in some people with AT may be more severe than previously appreciated, early nutritional intervention and ongoing nutritional support and education for patients, families, and caregivers are crucial [101, 149].

High-calorie foods are then recommended, and a gastrostomy tube (G-tube or feeding tube) is rarely used. A gastrostomy tube is recommended when a child cannot eat enough to grow, is not gaining weight and when dysphagia with aspiration causes breathing problems and/or when meals take too long or stressful [150].

People with IgG deficiency or impaired antibody function should receive standard immunoglobulin replacement therapy. Despite the low T-lymphocyte count found, prophylactic antibiotic use to prevent opportunistic infections is not necessary, unless individuals are treated chronically with corticosteroids, other immunosuppressive drugs, or chemotherapy [56, 84, 85]. Individuals with normal ability to produce antibody should receive an annual influenza vaccine, and additional pneumococcal vaccines at intervals to maintain high levels of antipneumococcal antibodies [85].

Cutaneous granulomas can be persistent, progressive, and very difficult to treat. To date, treatment has been attempted with topical and systemic corticosteroids, intravenous immunoglobulin, antitumor necrosis factor therapy, and antiviral therapy, with either mediocre or transient results [96, 151]. Only in immunodeficient patients with DNA repair disorders who underwent hematopoietic stem cell transplantation due to cancer observed granuloma healing [152, 153, and own observation].

### *Ataxia Telangiectasia DOI: http://dx.doi.org/10.5772/intechopen.112005*

In adolescent females, sex hormone replacement therapy may need to be considered to support optimal linear growth, development of secondary sex symptoms, and prevention of osteoporosis. Vitamin D levels should be monitored and treated with an appropriate dose [12].

Despite the poor prognosis of many AT cancers, they manage to be successfully treated. Cancer treatment should only take place in specialized oncology centers and only after consultation with a clinician who has specific experience in AT. Standard cancer treatment regimens should be modified to minimize or prevent cytotoxicity from radiomimetic drugs [73, 85]. Radiotherapy can only be used exceptionally and at reduced doses. The use of cyclophosphamide needs to be monitored as late onset of severe hemorrhage from bladder telangiectasia has been observed [154]. Even with modified therapy, late complications of chemotherapy are observed in some people with AT [155]. Although routine bone marrow transplantation is not currently recommended [156], it has however been performed successfully in several cases of hematopoietic malignancies in AT [157, 158].
