About one quarter of patients with low risk myelodysplastic syndromes may present with isolated thrombocytopenia, defined by International Prognostic Scoring System (IPSS) as a platelet (PLT) count < 100 Gi/L. Primary immune thrombocytopenia (ITP) is defined as an acquired immune-mediated disorder characterized by isolated thrombocytopenia, PLT count <100 Gi/L, and the absence of any obvious initiating and/or underlying cause of the thrombocytopenia (Rodeghiero et al, Blood, 2009). Recent guidelines consider bone marrow (BM) aspirate informative in patients > 60 years of age, those with systemic symptoms or abnormal signs or in some cases where splenectomy is considered (Provan et al, Blood, 2009). We performed a retrospective chart analysis between January 2008 and July 2012 of all patients referred to our clinic for thrombocytopenia but with a PLT count 100– 149 Gi/L. The aim of the study was to evaluate whether BM aspirates in these patients be informative.
Twenty-six cases (18 males/8 females) of mean age 59 ± SD 17 years were evaluated at our clinic for a PLT count below normal lab range values, > 100 Gi/L. At the time of evaluation none had bleeding symptoms. PLT counts ranged from 101 to 149 Gi/L, mean 122 Gi/L. Five patients had an enlarged spleen. BM aspirates identified 20 patients with low IPSS risk MDS. Cytogenetics were obtained in 15 cases: 7 normal, 2 del20q, 6 –Y. Twelve patients were aged < 60; 8 (66%) were diagnosed with MDS. Amongst the 14 patients with an indication for BM aspirate (age > 60), 12 (86%) had MDS.
The thresholds of PLT count 100 Gi/L and age 60 years for BM aspirate in patients with isolated thrombocytopenia reduces the diagnostic rate of MDS. In our retrospective review, 66% of patients (younger age and PLT > 100 Gi/L) would not have had MDS diagnosed. BM aspirate should be considered irrespective of age, since more than half of the patients in our case review had MDS with PLT > 100 Gi/L as a single cytopenia and age under 60.
No relevant conflicts of interest to declare.
Asterisk with author names denotes non-ASH members.