Severity of cutaneous findings predict the presence of systemic symptoms in pediatric maculopapular cutaneous mastocytosis.

Although the prognosis of maculopapular cutaneous mastocytosis (MPCM), also referred to as urticaria pigmentosa, is often benign, clinicians lack evidence to reliably predict those at risk of associated systemic manifestations. We sought to elucidate clinical markers of disease severity to provide better treatment and prognostic information for individuals with MPCM. A retrospective chart review querying characteristics of children diagnosed with MPCM in the Emory Dermatology Clinic was performed. Follow-up was obtained through a clinical encounter or telephone interview. Linear regression was used to determine predictors of the number of MPCM-related systemic symptoms. Of 67 subjects, 57% were male, and the mean age of onset was 4.5 months. The maximum number of MPCM lesions was 1 to 10 in 16%, 11 to 30 in 33%, 31 to 50 in 25%, 51 to 100 in 6%, and more than 100 in 20% of subjects. For their MPCM lesions, 46% of subjects reported itching, 34% flushing, and 25% blistering. Reported systemic symptoms included diarrhea (22%), abdominal pain (15%), wheezing or dyspnea (13%), vomiting (10%), bone pain (10%), headaches (8%), cough (10%), rhinorrhea (8%), irritability (6%), and anaphylaxis (1.5%). In a multivariate linear regression analysis, the maximum number of MPCM lesions (p = 0.02) and the number of skin symptoms (p < 0.01) were statistically significant predictors of the number of systemic symptoms, controlling for age of onset, body sites involved, and sex. The correlation between cutaneous findings and symptomatology could aid clinicians in identifying individuals with MPCM who might warrant systemic evaluation and therapy.