Clinical manifestations of hemoglobin Chico at high altitude.

Hemoglobin Chico is a rare hemoglobinopathy characterized by low oxygen affinity and a right-shifted oxygen dissociation curve. Detailed clinical evaluations of affected individuals have not been previously reported. We therefore report on the clinical features of Hemoglobin Chico in a Latino male living at high altitude, who desired to participate in school sports. As a young boy with asthma, he had the unusual finding of growth delay and digital clubbing which improved with asthma control. At 16 years of age, he had mild anemia and a decreased pulse oximetry (83%) but sufficient pulmonary reserve to participate in physically demanding activities.