Adults (upper row) CgA serum levels (A), correlation of CgA with gastrin (B) and Tryptase (C). Pediatric patients (lower row) with parallel analysis shown in (D), (E) and (F). For D–F, ● = UP, ● = mastocytomas, ● =DCM, and ● = ISM, and ● = children with an unknown diagnosis. Data indicates that all subjects with mastocytosis exhibit normal levels of CgA (excluding use of PPIs), which correlates with gastrin but not tryptase. No patients were excluded from analysis. Patients were treated with H2 antagonists alone, and H2 plus PPI, for a median of 6.3 and 5.3 years, respectively.