Introduction
Ataxia telangiectasia is an autosomal recessive disorder caused by a defect in the ATM gene which encodes for DNA repair enzymes. It is one of the inherited combined immunodeficiency disorders. It typically presents in early childhood with abnormal movements.
Epidemiology
- Incidence: 0.03 cases per 100,000 person-years
- Peak incidence: 1-5 years
- Sex ratio: 1:1
| <1 | 1-5 | 6+ | 16+ | 30+ | 40+ | 50+ | 60+ | 70+ | 80+ |
Clinical features
Features
- cerebellar ataxia
- telangiectasia (spider angiomas)
- IgA deficiency resulting in recurrent chest infections
- 10% risk of developing malignancy, lymphoma or leukaemia, but also non-lymphoid tumours
Differential diagnosis
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Comparison of Friedreich's ataxia and ataxia telangiectasia. Note in particular how ataxia telangiectasia tends to present much earlier, often at the age of 1-2 years