Infantile and juvenile spinal muscular atrophy

Analysis of Creatine Kinase Activity in 504 Patients with Proximal Spinal Muscular Atrophy Types I–III from the Point of View of Progression and Severity

“…It was concluded that the differences between the subgroups are attributed to the relatively higher muscle mass in probands with higher CK levels, since skeletal muscle is the largest reservoir of CK in the body [22]. This view is furthermore supported by other studies showing increased CK levels at a later age, around puberty, in mild SMA [1,2,4]. Heyck et al [1] suggested that abnormal amounts of enzymes are probably derived from those muscle fibres which are still unimpaired by denervation.…”

“…Many studies on SMA have reported elevated serum creatine kinase (CK) activities in a variable proportion of patients. Whereas previous reports have suggested that the CK activity in severe SMA type I (Werdnig-Hoffmann disease) is not increased [1], about 40-70% of patients with the milder SMA type III (Kugelberg-Welander disease) show elevated CK values [1][2][3][4][5]. However, the percentage of patients with raised CK levels ranges from 20% [6] to 100% [7] and reflects the different modes of ascertainment in the mostly small series of patients.…”

“…It has generally been assumed that the CK activity in patients with proximal SMA is more likely to be elevated in the chronic forms II and III than in the severe type I [1,2,4,8] but the few systematic studies on CK activity versus SMA phenotype have mainly concentrated on chronic type II SMA. Moreover, previous studies have indicated a relation between CK activity and duration of illness [8].…”

Population data on acute infantile and chronic childhood spinal muscular atrophy in Warsaw

“…Grouping of the patients into ASMA and CSMA was made according to the classification of Hausmanowa-Petrusewicz et al (1968). Index cases were considered as suffering from ASMA when they had died by the end of the 4th year of life and had never been able to walk, whereas patients were classified as having CSMA when they were alive after their 4th birthday (regardless of the type of SMA).…”

“…Acute infantile spinal muscular atrophy (ASMA) and chronic childhood spinal muscular atrophy (CSMA) are well-recognized anterior horn cell disorders caused by an unknown molecular defect that might result from mutations at two different gene loci; they generally follow autosomal recessive inheritance (Baraitser 1982;Bundey and Brett 1985;Dubowitz 1978;Emery et al 1976;Hausmanowa-Petrusewicz et al 1968;Pearn 1980). Whereas the fatal ASMA (Werdnig-Hoffmann disease or type Ia SMA) is reported to be a separate disease (Emery 1971;Pearn et al 1973), the identity of the relatively milder CSMA (sub-acute or type Ib SMA, early childhood or type II SMA, and Kugelberg-Welander disease or type III SMA) has been the subject of considerable controversy (Emery 1971;Hausmanowa-Petrusewicz et al 1976, 1979Pearn et al 1978) 9 ASMA is possibly one of the most common fatal autosomal recessive diseases of childhood with an incidence in North-East England of at least 1 in 25 000 live births (Pearn 1973).…”