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Utility of Dissociated Intrinsic Hand Muscle Atrophy in the Diagnosis of Amyotrophic Lateral Sclerosis
Published on: March 4, 2014
IgG subclass deficiency in amyotrophic lateral sclerosis
B Ostermeyer-Shoaib1, B M Patten
1Department of Neurology, Baylor College of Medicine, Houston, Texas 77030.
Acta Neurologica Scandinavica
|March 1, 1993
Summary
This study investigated immunoglobulin G (IgG) subclasses in amyotrophic lateral sclerosis (ALS) patients, revealing a potential defect in T-cell dependent IgG expression, suggesting immune dysregulation in ALS.
Area of Science:
- Immunology
- Neurology
Background:
- Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease.
- The role of T-cell dependent versus T-cell independent immune mechanisms in ALS pathogenesis is not fully understood.
Purpose of the Study:
- To investigate immunoglobulin G (IgG) subclass levels in ALS patients.
- To explore potential immune system dysregulation in ALS.
Main Methods:
- Measurement of IgG subclasses (IgG1, IgG2, IgG3, IgG4) in 25 ALS patients.
- Assessment of T-cell dependent and T-cell independent antibody expression.
- D-xylose breath test and duodenal aspirate cultures to assess for small bowel overgrowth.
Main Results:
- 16 out of 25 ALS patients showed deficiency in T-cell dependent IgG1 or IgG3, with normal T-cell independent IgG2 and IgG4.
- Five untreated patients had normal total IgG despite IgG subclass deficiency.
- Six patients with prior immunosuppressive treatment had deficient total IgG.
- Eight of 14 patients tested had evidence of small bowel overgrowth.
Conclusions:
- Findings suggest a defect in IgG subclass expression in ALS patients.
- This defect may indicate impaired T-cell dependent immune responses in ALS.
- Small bowel overgrowth was observed in a significant portion of ALS patients, warranting further investigation.
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