For 3 years, my 25 year old son has been treated for iron deficiency anemia with iron replacement. At first, the effect was positive. His Hgb increased from 5.0 to 14.8 and Hct. went from 20.8 to 36.2. His iron level went from 2 to normal. During the time he went through Army basic training (and was not on iron because the doctors felt his problem was corrected), he again developed a low hgb and hct, with low normal RBCs (but were microcytic and hypochromic), jaundice, and low iron levels. This state (with exception of jaundice) has persisted for the last 2 years despite oral liquid iron replacement. Currently, his Hgb is 10.0 and his hct. is 28, with low normal RBC count and hypochromic, microcytic cells. Symptomatically, he states he is not fatigued, short of breath, or weak. He is able to physically carry out his duties in the infantry. One problem, though, has been his inability to shake off relatively minor respiratpory infections. His physician now suspects that he has a form of Thalassemia. My question is this: Can this disorder remain undetected for approximately 21 years without any symptomology and be triggered by some event (such as heavy physical exertion combined with poor dietary iron and protein intake).