Table 2.

Twenty-five of 96 (26%) genetically confirmed DM2 members of the Registry had a previous misdiagnosis based on review of medical records. Limb-girdle muscular dystrophy was the most common misdiagnosis (n=5).

Previous misdiagnosis	Year of misdiagnosis	Diagnosing physician	Diagnostic delay (years)
Acid maltase deficiency	1995	Neurologist	12
Antibody negative Hashimoto's thyroiditis	2007	Neurologist	2
Chronic fatigue syndrome	2006	Neurologist	2
Chronic rhabdomyolysis	2004	N/Aa	7
Charcot-Marie-Tooth disease	2001	General practitioner	48
Degenerative joint disease	2009	General practitioner	18
Dystrophy unknown etiology	1997	Neurologist	18
Exertional muscle pain syndrome	2003	Neurologist	13
Fibromyalgia	1980	Neurologist	28
Graves’ disease and Addison's disease	1975 & 1994	Neurologist	29
Hypokalemic periodic paralysis	N/A	Neurologist	7
Inclusion body myositis	2006	Neurologist	20
Inclusion body myositis	2007	Neurologist	9
Limb-girdle muscular dystrophy	N/A	N/A	36
Limb-girdle muscular dystrophy	N/A	Neurologist	24
Limb-girdle muscular dystrophy	1997	Neurologist	16
Limb-girdle muscular dystrophy	1996	N/A	25
Limb-girdle muscular dystrophy	2006	Neurologist	26
Multiple sclerosis	2004	Neurologist	1
Myasthenia syndrome	2002	Neurologist	6
Nerve damage, unknown etiology	1998	N/A	38
Pseudo-myotonia	2002	Neurologist	35
Rheumatoid arthritis	2003	Neurologist	2
Shoulder girdle dystrophy	2004	Neurologist	1
Weakness due to pregnancy	1980	Neurologist	20

^aN/A = Not available