Systemic mastocytosis. Study of 14 cases

We have analyzed the clinical, analytical and evolutive data of 14 cases of systemic mastocytosis (SM) diagnosed in our hospital between 1991-1996 and we have compared these results with those of other published series. Clinical parameters, analytical profiles, peripheral hematologic data, radiologic data and histological study were collected. Following Metcalfe's criteria, the patients were clasified in 4 groups: a) group 1, indolent mastocytosis; b) group 2, hematologic disorders; c) group 3, aggressive lymphadenopathic mastocytosis with eosinophilia, and dl group 4, mastocytic leukemia. The average age at diagnosis was 52.4 years, range 25-83, and 64% were females. The mean follow-up was 2 yr. In most of the cases (71.4%) the initial complaint was urticaria pigmentosa. The predominant clinical features were pruriginous-eritematous skin lesions (in 11 cases), and digestive symptoms (in 10 patients). The most usual biochemical disorder was the rise of serum alkaline phosphatase level (in 8 patients), while lactate-dehydrogenase (LDH) was normal in all the cases. The most striking roentgenologic features were oteopenia, observed in 50% of our patients. Pheripherical hematological disorders were discovered in 8 patients (64.3%) and in one of them circulating mast-cells were observed. The bone marrow was involved in all patients (100%) and in two of them mielodysplasic features were found. The diagnostic of SM is difficult in the absence of skin lesions. The skin lesions are very common in systemic mastocytosis. Bone marrow involvement is constant, so its study has a high diagnostic rentability.