Cultures of hematopoietic precursor cells can be helpful in differentiating between
primary polycythemia (polycythaemia vera, PV) and reactive secondary
polycythemia: in PV erythroid precursors form hemoglobinized colonies in the absence of added
erythropoietin (epo) (= endogenous erythroid colonies), whereas in normals and in patients with secondary
polycythemia, formation of erythroid colonies is dependent on added epo. We have performed cultures of peripheral blood precursors from 132 patients with elevated
hemoglobin in the presence/absence of added epo. In 48/132 patients we assumed that PV was the cause of
polycythemia. In 80/132 patients no endogenous colonies appeared and the
polycythemia was judged secondary. 23 PV patients were examined repeatedly. In 18 of them the first diagnosis was confirmed by subsequent cultures; in 5 cases endogenous colonies, which had been present in the first cultures, were no longer detectable. A questionnaire on the subsequent
clinical course was sent to 108 treating physicians. 77 questionnaires were answered correctly and returned. In 86% of these patients, our culture diagnosis of PV was either confirmed or another
myeloproliferative disorder had been found as a cause of endogenous colonies. In 14% our diagnosis of PV had been false positive. On the other hand, our diagnosis of secondary
polycythemia was confirmed in 85% of the patients; its most frequent cause was cigarette smoking and
chronic bronchitis and only rarely was it associated with heart or
kidney disease. 5/77 patients had persistently elevated Hb without an evident cause, and in 3/77 the Hb normalized spontaneously.(ABSTRACT TRUNCATED AT 250 WORDS)