The impact of duration of untreated symptoms in children with juvenile dermatomyositis (JDM) on clinical and laboratory findings at diagnosis was studied in 166 patients enrolled in the National JDM Research Registry and examined at Children’s Memorial Hospital, Northwestern University; Loyola University; and University of Chicago, Chicago, IL; and other centers in the US. The girl:boy ratio was 2:1; 74% white, 13% Hispanic, and 10% African-American. Duration of untreated disease ranged from .07 month to 98 months (median, 4.04 months). Age at diagnosis and duration of disease showed no significant differences with gender or race. Rash (heliotrope eyelids, malar erythema, Gottron’s metacarpal papules) was the first symptom reported by 100 patients (65%), and muscle weakness was the first in 44 (29%). Nine (6%) had both rash and weakness at disease onset. The severity of muscle symptoms based on disease activity scores (DAS 0-11) was greater in nonwhite (6.77) cf white (4.71) children (P>.0005). Mean DAS total (skin rash and muscle weakness) was higher in nonwhite (12.52) cf white (10.45) children (P=.001). DAS skin rash (scale 0-9) ranged from 3-9 (mean, 6) and did not vary with duration of untreated disease, whereas DAS muscle weakness (scale 0-11) ranged from 0-11 and declined gradually with duration of untreated disease (P>.0005). More children with untreated JDM were in lower percentiles for height and weight than their healthy controls, irrespective of the duration of untreated disease. In addition to rash and muscle weakness, symptoms at diagnosis of JDM in order of frequency included capillary dilation and telangiectasia, followed by arthritis, dysphagia, and abdominal pain. Dysphagia and arthritis were more common in older children, whereas cutaneous calcifications were correlated with duration of untreated disease (P=.006). Levels of all 4 routine muscle enzymes (CK, aldolase, LDH, and SGOT/AST) were lower with longer duration of untreated disease; they were normal in 13-26% of children at the initial clinic visit. CK level was normal in 33 untreated JDM cases, despite muscle weakness. 
COMMENT. Duration of disease and age are important in reviewing the symptoms and serum enzymes at time of diagnosis of JDM. Children with longer disease duration tend to have fewer diagnostic findings of JDM, and their muscle enzymes are often normal. Older children have more symptoms of arthritis and dysphagia compared to children age 6 years and under. Systemic vasculopathy, with decreased food absorption, and dysphagia may account for the lower percentile height and weight of children with JMD. Early diagnosis and prompt institution of treatment are recommended.
Dysphagia in facioscapulohumeral muscular dystrophy (FSHD) was demonstrated in 7 of 8 adults, most having weakness of tongue and jaw muscles . This finding is contrary to the original description of FSHD by Landouzy and Dejeurine in 1885, emphasizing the integrity of the muscles of the tongue and jaw. Dysphagia appears to occur only in severe cases of FSHD, and does not involve muscles of the pharynx.