ABSTRACT
Histiocytosis disorders include a wide group of disorders characterized by monocytes, macrophages and dendritic cell infiltration of different tissues. There are few clinico-epidemiologic studies of such disease. Our study was designed to look at the clinico-epidemiological features and outcome of patients with histiocytosis disorders in Northeast Egypt. Twenty-seven cases with histiocytosis disorders accrued over a 5-year period were analyzed and classified as having unifocal, multifocal, or multisystem disease. They were 14 males and 13 females. Twenty-two patients representing 81.5% of cases were more than two years of age while 5 patients (18.5%) were less than 2 years. Lymphadenopathy was the commonest presentation (55.55%) followed by bone lesions (44.44%). Involvement was unifocal in 12, multifocal in 10, and multisystem in 5 cases. The histological features were relatively uniform regardless of the clinical severity, and consisted of Langerhans cells, eosinophils, histiocytes, plasma cells, giant cells and fibrosis. The treatment consisted of a combination of surgery, chemotherapy, and/or radiotherapy. Lymphadenopathy was the most common clinical presentation in our locality. Response to treatment was poor in patients with multisystem disease. Patients with age less than 2 years were more likely to have increased risk of morbidity and mortality, due to widespread disease.