A pitfall in hemoglobin electrophoresis. Artefactual minor unstable hemoglobin results from improper specimen handling.
الكلمات الدالة
نبذة مختصرة
Blood specimens are commonly mailed for the purpose of hemoglobin studies, such as identification of abnormal hemoglobins and measurement of hemoglobins A2 and F. In a period of a few months, the author examined eight specimens sent from a referring laboratory, in which cellulose acetate electrophoresis (p H 8.6) revealed a discrete minor band in a position approximately midway between the positions of hemoglobins A and S. For each specimen, tests for hemoglobin instability were positive. In one specimen, marked methemoglobinemia and sulfhemoglobinemia were also demonstrated. Further studies of fresh specimens obtained from the same subjects failed to demonstrate any hemoglobinopathy. The abnormal band in the original eight specimens was an artefact resulting from improper specimen handling--that is, unduly long transit times without refrigeration. The aftefactual band had electrophoretic mobility identical to that of methemoglobin derived from hemoglobin A.