False-Positive Test For Hemoglobin S

To the Editor.—  The recent critique, "Sickledex Test for Hemoglobin S" (218:1679-1680, 1971), lists several conditions which will produce a false-positive Sickledex test result. This includes polycythemia, protein abnormalities, and certain abnormal hemoglobinopathies.We recently observed a false-positive Sickledex test result in a patient who would not fit in the above categories.

Report of a Case.—  A 16-year-old Negro girl came to our emergency room with complaints of lethargy and menometrorrhagia. Past and family history were not pertinent. Review of systems disclosed only excessive menses and heavy vaginal bleeding between menstrual periods. Results of physical examination were unremarkable except for pale nail beds and conjunctivae. Values from laboratory studies were as follows: hemoglobin, 2.7 gm/100 ml; hematocrit, 9.7%; red blood cell count, 1,640,000/cu mm; white blood cell count, 2,000/cu mm; differential cell count, normal; red blood cell morphological analysis, marked hypochromia and microcytosis; serum iron, 12 mg/100 ml; total