[MIM 208 900, 208 910]

(Louis-Bar syndrome)

Prevalence: 1-9/100,000. Recessive autosomal transmission of a mutation of the ATM gene (11q22.3). This mutation results in the inactivation of an ubiquitous protein-kinase playing an important role in the control of the repair of double-stranded DNA breaks. The effects are most pronounced in endothelial cells (brain, skin, conjunctiva) and in the Purkinje cells of the cerebellum. A rare variant of the disease (A-T like disorder) is due to the inactivation of the MRE11 gene (11q21), also intervening in the repair of double-stranded DNA breaks.

Cytogenetics: translocation7/14 in 2/3 of the cases.

This failure of DNA repair mechanisms results in a highly variable phenotype that combines:

-         cutaneous and conjunctival telangiectasia 

-         progressive cerebellar ataxia, 

-         immune deficiency due to IgA deficiency, 

-        an increased level of a α-foetoprotein

-         frequent ENT and pulmonary infections, causing a progressive respiratory insufficiency

-         a high sensitivity to ionizing radiation, 

-         a predisposition to lymphoid malignancies.

Most of the patients are wheelchair-bound since the teenage years. Their life expectancy is 25-30 years. A multidisciplinary management (pneumology, neurology and nutrition) is essential.

Anesthetic implications: 

susceptibility to respiratory infections (bronchiectasis); pre - and post-operative  respiratory physiotherapy ; aseptic precautions.

References:

-         Lockman JL, Iskander AJ, Bembea M, Crawford TO, Lederman HM, McGrath-Morrow S, Esaley RB.
Anesthetic and perioperative risk in the patient with Ataxia-Telangectasia. 
Pediat Anesth 2012; 22:256-62.

Updated: November 2019