A. ROVÓ ET AL. ERYTHROGRAM PATTERN OF SIDEROBLASTIC CHANGES 333 Six RS-patients did not have an erythrogram with a RS-pattern (2 Acute myeloid leukemia, 2 MDS/ myeloproliferative neoplasms, 1 MDS, 1 hemophago- cytosis). All six patients had increased iron stores, 5/6 were anemic and did not have the typical numeri- cal parameters (4/6 high MCV; 5/6 < 20% RDW; 5/6 < 1.1% hypoRBC). In the second step of the study, we compared the validation group with the initial RS-patients. We iden- tiﬁed prospectively 28 cases with a RS-pattern; 7/28 cases were excluded because they had a dry tap in the bone marrow aspiration. We found RS in the bone marrow of 20/21 evaluable cases, with a median of 50% RS (range 15–75%) Figure 2. All of them had increased iron stores. The patient with a typical RS- pattern, but without RS in the bone marrow, had depleted iron stores. As expected, RBC-indices of both groups were similar (P > 0.10) (Table 1). Hence, by Figure 2. Erythrograms of all 20 patients of the validation group with a typical RS-pattern and ringed sideroblasts in the bone marrow. 2009 The Authors Journal compilation 2009 Blackwell Publishing Ltd, Int. Jnl. Lab. Hem. 2010, 32, 329–335