[Beta thalassemia intermedia: clinical characteristics and molecular analysis. Case series].

Beta thalassemia intermedia is a quantitative haemoglobinopathy covering a broad clinical spectrum, that results from the presence of one or two HBB gene mutations associated with secondary and/or tertiary genetic modifiers. We analyze the clinical and laboratory features of 29 patients with beta thalassemia intermedia, assessed over a period of 23 years. Median age was 10.8 years (range: 0.34-60.4). Hypochromic microcytic anemia was seen in 100% of the patients, while only 17.2% had splenomegaly and occasional transfusion requirement. The molecular analysis of patients detected: 3 with two HBB affected genes; 2 with one HBB affected gene and alpha quadruplicate/triplicate genes; 23 with one HBB affected gene and alpha triplicate genes and 1 with two HBB affected genes and polymorphisms of gamma genes. The adequate identification of these patients enables us to give appropriate genetic counseling and implementation of regular clinical follow up.