Louis-Bar syndrome

a·tax·i·a tel·an·gi·ec·ta·si·a

, ataxia-telangiectasia [MIM*208900]
an autosomal recessive multisystem disorder consisting of ataxia, ocular apraxia, hypotonia, proprioceptive sensory loss, areflexia, and choreoathetosis; onset typically in early childhood; systemic features include increased susceptibility to malignancies, conjunctival and cutaneous telangiectasia, and recurrent pulmonary infections due to immunodeficiencies. Caused by breaks on chromosome 11q at q22-q23, producing failure of DNA repair.

Louis-Bar syndrome

ataxia-telangiectasia

An autosomal recessive condition (OMIM:208900) characterised by sinopulmonary infections, choreoathetosis (wobbly gait), slurring of speech, muscular atrophy and “red eyes”.
 
Clinical findings
Progressive cerebellar ataxia, oculocutaneous telangiectasia, thymic aplasia or hypoplasia (cellular defect), immune deficiency, autoimmune phenomena.

Lab
Decreased IgG4 and IgA2, ± decreased IgE, increased AFP.

Genetics
Increased susceptibility to radiation-induced chromosomal damage (breakage and rearrangement due to defective DNA repair); increase in lymphoid, breast and other cancers.

Immunity
Immune complex (IC) deposits in glomeruli, choroid plexus, heart valves and synovium; increase in vasoactive amines (histamine), serotonin, IgE and platelets; presence of macrophages; antigen and antibody valences; class of antibody; antibody:antigen ratio; affinity of antibody:antigen; types of vasculature involved depend on the tissue through which the ICs pass and response of the reticuloendothelial system to the ICs.

Diagnosis
Clinical findings, cell culture for radiosensitivity and atypical radioresistant DNA synthesis; cell culture for prenatal diagnosis of ATM mutation.

Management
Symptomatic, supportive; aggressive treatment of infections and surveillance for malignancy.

Louis-Bar,

Denise, mid-20th century Belgian neuropathologist.
Louis-Bar syndrome - an autosomal recessive disorder characterized by cerebellar ataxia and telangiectasia. Synonym(s): ataxia telangiectasia
References in periodicals archive ?
Ataxia-telangiectasia (AT), also known as Louis-Bar syndrome, is a hereditary autosomal recessive progressive multisystem disease.