Thrombocytopenia in the Absence of Splenomegaly in Patients with Type 1 Gaucher Disease: A Preliminary Analysis From the ICGG Gaucher Registry,

Patients with Gaucher disease frequently experience a delay in diagnosis despite clinical signs and/or symptoms. This delay is thought to stem from the rarity of the disease and physicians' inexperience with the constellation of disease manifestations that often overlap those of more common hematological illnesses. It has been the authors' experience that, in the absence of palpable splenomegaly, physicians are even less likely to consider the possibility of Gaucher disease in patients who have other typical manifestations such as chronic bone pain or hematological cytopenias. Using data submitted to the International Collaborative Gaucher Group (ICGG) Gaucher Registry, the largest single repository of Gaucher disease clinical information in existence, we sought to determine how commonly such patients are likely to be encountered.

To determine the frequency of patients with Gaucher disease who have little to no splenomegaly at diagnosis despite having concurrent moderate or severe thrombocytopenia.

Data were evaluated from all patients with Gaucher disease type 1 enrolled in the ICGG Gaucher Registry as of June 3, 2011 who had not been splenectomized before diagnosis and whose spleen volumes and platelet counts at the time of diagnosis were reported to the Registry. Splenomegaly was quantitated by MRI, CT or ultrasonic volumetric measurements and categorized as mild/none (≤5 multiples of normal [MN] based on a normal value of 0.2% of body weight), moderate (>5 to ≤15 MN) and severe (> 15 MN). Platelet counts were categorized according to thrombocytopenia categories of mild/none (≥120 ×10³/mm³), moderate (>60 to ≤120 × 10³/mm³) and severe (<60 × 10³/mm³).

A total of 612 patients with platelet counts and spleen volumes were identified. Of these, 96/612 (15.7%) had mild or no splenomegaly at the time of Gaucher diagnosis. Of these 96 patients, 37 (38.5%) had moderate thrombocytopenia and 6 (6.3%) had severe thrombocytopenia.

Type 1 Gaucher patients often present with moderate to severe thrombocytopenia but with either normal spleen volumes or with splenomegaly that is not likely to be clinically apparent. These patients may be at particular risk for diagnostic delay but no less susceptible to Gaucher disease morbidity than patients with a more typical presentation. Further description of this cohort with respect to genotype, demographics, and other disease manifestations will be presented.

Rosenbloom:Genzyme Corporation ; Shire Pharmaceuticals: Research Funding, Speakers Bureau; Genzyme Corp: Research Funding, Speakers Bureau. Kulke:Genzyme, a Sanofi Company: Employment. Taylor:Genzyme, a Sanofi Company: Employment. Weinreb:Genzyme Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Shire HGT: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Actelion Corporation: Speakers Bureau.