Can ATLD Begin During Adulthood?
No, Ataxia-Telangiectasia-Like Disorder (ATLD) does not begin during adulthood—it is a childhood-onset disease that typically presents with progressive cerebellar ataxia between ages 1-4 years, similar to classical ataxia-telangiectasia. 1, 2
Age of Onset
- ATLD is characterized by early childhood onset, with neurological symptoms appearing in infancy or early childhood, not in adulthood 2, 3
- The disease follows an autosomal recessive inheritance pattern caused by biallelic mutations in the MRE11 gene 2, 3
- In documented cases, including the first Italian siblings with ATLD, the disease had early onset with initial severe clinical presentation during childhood 2
Clinical Course into Adulthood
While ATLD does not begin in adulthood, patients who survive into adult years show a distinctive pattern:
- Very slow neurological deterioration occurs in adult age, which distinguishes ATLD from classical ataxia-telangiectasia 2
- Neurological impairment, ocular motor apraxia, and neuropsychological deficits progress much more slowly once patients reach adulthood 2
- Patients can develop compensatory eye and head motor strategies to manage ocular motor apraxia over time 2
Key Distinguishing Features from Classical AT
- ATLD shares the childhood onset pattern with classical ataxia-telangiectasia, where progressive cerebellar ataxia develops between ages 1-4 years 1
- Unlike classical AT where most children become wheelchair-bound by their teenage years, ATLD demonstrates a milder long-term progression 1, 2
- Both conditions feature oculomotor apraxia and progressive ataxia beginning in early childhood, not adulthood 1, 4
Common Diagnostic Pitfall
The critical error is mistaking the recognition of ATLD in an adult patient for adult-onset disease. ATLD may be diagnosed in adulthood when reviewing a patient's history reveals childhood-onset symptoms that were previously undiagnosed or misattributed 2. The 30-year clinical follow-up of Italian siblings demonstrates that while the disease was present from early childhood, detailed characterization continued into their adult years 2.