For doctors who have already seen several children with Ataxia Telangiectasia, diagnosis can usually be evoked by simple observation of the child. To avoid delays in diagnosis, it is important to know that:
They are often absent in early disease. Physicians examining a ataxic child may exclude ataxia telangiectasia if they don't observed any telangiectasa. Most of the time, these appear at about 6 years old and sometimes later.
ENT and Pulmonary Infections
When a child has repeated bronchial and ENT infections, many explanations are possible, but will, especially in serious cases, getting doctors to achieve an immune balance. The AT is a rare cause of immune deficiency, and moreover, it is inconsistent: almost 30% of children do not have immune deficiency or it does not impact their condition significantly. It might delay the correct diagnosis.
Ataxia Telangiectasia is often mistaken for congenital cerebellar ataxia, stable over time. Initially, poor balance and ataxia of the trunk are slowly progressing: they can be compensated by a normal psychomotor development between 2 and 6 years old which masks the progression of ataxia and gives the impression of progress. The correct clinical diagnosis is often not mentioned, until the progression of the disease become apparent, unless the patient has a brother or sister who is already affected.
Once the disease progression becomes evident, it is often referred to a Friedreich's ataxia. However, this disease occurs later (between 10 and 15 years) and is characterized by pes cavus and kyphoscoliosis. It combines a lack of reflexes and sensory signs: tingling, numbness, sometimes sensory disturbances, and cardiac signs.