Komaki et al, recently published an article in which they performed genetic testing for a mutation in LMNA, the gene that leads to L-CMD, in patients whose muscle biopsies showed a high degree of inflammation at age 2 years and younger. Out of 20 patients, they found 11 (55%) had mutations in LMNA consistent with a diagnosis of L-CMD. The article provides additional information on 9 patients with confirmed L-CMD. The 4 patients who achieved the ability to walk demonstrated a response to prednisone therapy. Given the degree of underlying inflammation on the muscle biopsy, one of prednisone’s actions may be as an anti-inflammatory agent. Prednisone was started between 10 months and 3 years with average length of treatment of 8 years. Patient information highlights the high incidence of heart arrhythmia in this form of CMD, both atrial and ventricular as well as conduction blocks. This underscores the need for at least an annual holter or event monitor and echocardiogram. More frequent testing is indicated with any symptoms suggestive of a heart rhythm disturbance: chest pain, chest discomfort, abdominal pain, loss of consciousness, fast heart rate, slow heart rate, pale, fatigue, shortness of breath. These symptoms may be intermittent.
Komaki H, Hayashi YK, Tsuburaya R, Sugie K, Kato M, Nagai T, Imataka G, Suzuki S, Saitoh S, Asahina N, Honke K, Higuchi Y, Sakuma H, Saito Y, Nakagawa E, Sugai K,Sasaki M, Nonaka I, Nishino I. Inflammatory changes in infantile-onset LMNA associated myopathy. Neuromuscul Disord. 2011 May 30. [Epub ahead of print]