Study of 962 patients indicates progressive muscular atrophy is a form of ALS
KenIkeda, Department of Neurology, Toho University Omori Medical Center, 6-11-1, Omorinishi, Otaku, Tokyo, 143-8541, Japan[email protected]
Yasuo Iwasaki
Submitted March 08, 2010
We read with great interest the article by Kim et al. who conducted a large clinical study of progressive muscular atrophy (PMA). [1] We agree that PMA is a form of amyotrophic lateral sclerosis (ALS) and would like to comment.
As the authors mention, some patients only have lower motor neuron (LMN) signs in familial ALS (FALS) with SOD1 mutations. The A4V point mutation is the most popular causative gene of SOD1 in North American FALS patients who exhibit rapid progression of pure LMN signs. [2]
Did SOD1 mutations exist in the 91 PMA patients studied by Kim et al.? We encountered FALS patients who had pure LMN signs without bulbar dysfunction. This family showed clinical features of PMA with a novel G85S mutation of SOD1. [3]
The revised El Escorial diagnostic ALS criteria exclude our patients from ALS category 4, although this SOD1 mutation is detected. We also agree with Kim et al. that the current diagnostic criteria need to be modified. [4]
References
1. Kim W-K, Liu X, Sandner J et al. Study of 962 patients indicates progressive muscular atrophy is a form of ALS. Neurology 2009;73:1686-1692.
2. Juneja T, Pericak-Vance MA, Laing NG, Dave S, Siddique T. Prognosis of familial amyotrophic lateral sclerosis: progression and survival in patients with glu100gly and ala4val mutations in Cu, Zn superoxide dismutase. Neurology 1997;48:55-57.
3. Takazawa T, Ikeda K, Hirayama T, et al. Familial amyotrophic lateral sclerosis with a novel G85S mutation of superoxide dismutase 1 gene: clinical features of Lower motor neuron disease. Intern Med (in press 2009).
4. Brooks BR, Miller RG, Swash M, Munsat TL. El Escorial revisited: revised criteria for the diagnosis of amyotrophic lateral sclerosis. Amyotroph Lateral Scler Other Motor Neuron Disord 2000;1:293-299.
We read with great interest the article by Kim et al. who conducted a large clinical study of progressive muscular atrophy (PMA). [1] We agree that PMA is a form of amyotrophic lateral sclerosis (ALS) and would like to comment.
As the authors mention, some patients only have lower motor neuron (LMN) signs in familial ALS (FALS) with SOD1 mutations. The A4V point mutation is the most popular causative gene of SOD1 in North American FALS patients who exhibit rapid progression of pure LMN signs. [2]
Did SOD1 mutations exist in the 91 PMA patients studied by Kim et al.? We encountered FALS patients who had pure LMN signs without bulbar dysfunction. This family showed clinical features of PMA with a novel G85S mutation of SOD1. [3]
The revised El Escorial diagnostic ALS criteria exclude our patients from ALS category 4, although this SOD1 mutation is detected. We also agree with Kim et al. that the current diagnostic criteria need to be modified. [4]
References
1. Kim W-K, Liu X, Sandner J et al. Study of 962 patients indicates progressive muscular atrophy is a form of ALS. Neurology 2009;73:1686-1692.
2. Juneja T, Pericak-Vance MA, Laing NG, Dave S, Siddique T. Prognosis of familial amyotrophic lateral sclerosis: progression and survival in patients with glu100gly and ala4val mutations in Cu, Zn superoxide dismutase. Neurology 1997;48:55-57.
3. Takazawa T, Ikeda K, Hirayama T, et al. Familial amyotrophic lateral sclerosis with a novel G85S mutation of superoxide dismutase 1 gene: clinical features of Lower motor neuron disease. Intern Med (in press 2009).
4. Brooks BR, Miller RG, Swash M, Munsat TL. El Escorial revisited: revised criteria for the diagnosis of amyotrophic lateral sclerosis. Amyotroph Lateral Scler Other Motor Neuron Disord 2000;1:293-299.
Disclosure: The authors report no disclosures.