SUMMARY
1. Myotonic dystrophy is an autosomal dominant disease characterized by the following features:
Difficulty relaxing contracted muscles
Muscle weakness and wasting
Cataracts
Hypogonadism
Cardiac conduction defects
Cognitive deterioration in adults
2. Immunologic abnormalities reported in patients include low IgG, IgM and IgA levels, lymphopenia, and decreased T cell numbers. Patients generally have not had increased susceptibility to infections.
3. Most cases of myotonic dystrophy are caused by trinucleotide repeat expansion in the 3 untranslated region of the DMPK gene (which encodes for the dystrophia myotonica protein kinase).
OVERVIEW
Myotonic dystrophy is an autosomal dominant disease characterized by the following features:
Difficulty relaxing contracted muscles
Muscle weakness and wasting
Cataracts
Hypogonadism
Cardiac conduction defects
Cognitive deterioration in adults
Immunologic abnormalities reported in patients include low IgG, IgM and IgA levels, lymphopenia, and decreased T cell numbers. Patients generally have not had increased susceptibility to infections.
Most cases of myotonic dystrophy are caused by trinucleotide repeat expansion in the 3 untranslated region of the DMPK gene (which encodes for the dystrophia myotonica protein kinase).
EVALUATION
Step 1: Immune Evaluation
-IgG, IgM, IgA
-Specific antibody responses to vaccine antigens
-CBC with Differential
-Lymphocyte subset enumeration by flow cytometry (CD3, CD4, CD8, CD19, CD16/56)
-Low IgG, IgM, and IgA, lymphopenia, and decreased T cell numbers have been reported in patients.