A case of unusually refractory immune thrombocytopaenia treated with splenic artery embolization and Rituximab

No abstract available. DOI: http://dx.doi.org/10.4038/jdp.v6i1.4428 Journal of Diagnostic Pathology 2011 (6); 1: 49-51

one week the platelet count rose to 240х10 /L and prednisolone was tailed off by 5mg/week from the initial dose. Within two weeks he was 9 re admitted with a platelet count of 8 х10 /L, without bleeding. While on the tailing off dose of prednisolone, he was started on intra venous (IV) methyl-prednisolone 1g/day for 3 days. After one week as the platelet count was less 9 than10х10 /L, a single dose of intra venous immunoglobulin (IVIg) 1g/kg /body weight was infused. Failing IVIg, Azathioprine 100mg /day and Mycophenolate mofetil 250mg/day were added. After one month of the initial diagnosis, the patient was transferred from the local hospital to the National Hospital of Sri Lanka (NHSL) for further management as his 9 platelet count remained very low at 6 х10 /L. Rituximab 375mg/m was given weekly for 4 weeks and the patient tolerated treatment with no side effects. He was discharged after 3 months of admission. The patient leads a asymptomatic and normal life but his platelet 9 count remains low, at around 10х10 /L.

Discussion
Over 90% of patients with ITP initially respond to steroid treatment (platelet count increases up 9 to 30-50 x 10 /L) (1). They respond within days to weeks to oral prednisolone, and in few days IV methylprednisolone (1). This patient Journal of Diagnostic Pathology 2011 (6); 1: 49-51 1,2, 4 3 Haematology unit , The National Hospital of SriLanka, Sri Lanka Ward 50,The National Hospital of SriLanka, Sri Lanka.
Correspondence: e-mail: manoripremachandra@gmail.com responded well to steroids initially, confirming the diagnosis of an immune aetiology. However an acceptable platelet count could not be sustained. Intravenous Immunoglobulins were not useful either. Even the second and third therapeutic option of Azathioprine and Mycophenolate mofetil were not effective (1,2).
Rituximab, a genetically engineered human anti-CD20 monoclonal antibody is an expensive second line drug, useful in treating a proportion of patients with chronic refractory ITP and approximately Splenectomy is the surgical therapeutic intervention recommended in ITP. About 80% of patients respond to splenectomy within 1-24 days (1). Splenic artery embolization is a minimally invasive mode of splenectomy, which is done by occluding the splenic artery by thrombogenic material (coils or glue) under CT guidance with local anaesthesia. This method can be used before surgical splenectomy to reduce blood loss and facilitate the surgery or as an alternative to conventional splenectomy (3). Splenic artery embolization alone had been used as a treatment method for ITP resulting in sustained increase in platelet count for many years (4). In this patient there was a transient increase of platelet count after the procedure but it did not last for more than few hours.
Surgical splenectomy would have been considered after splenic artery embolization 9 when the platelet count reached 70x10 /L. It was confirmed, that there was no viable spleen after splenic artery embolization by radiological assessment. Although the appearance of Howell-Jolly bodies confirmed splenectomy, absence of other features in the blood picture suggestive of splenectomy was questionable.
60% respond with, approximately 40% achieving a complete response, generally after 1 to 2 weeks of treatment (5). However the platelet count did not show any increment even after 12 weeks of completing Rituximab treatment. Therefore this patient was considered to be unusually resistant to treatment but able to tolerate severe thrombocytopenia (i.e. platelet counts as low as 9 4 х10 /L.) relatively well with near normal quality of life. The present case is a challenge to the clinician to decide on implementing further treatment methods while the patient remains totally asymptomatic, but with severe thrombocytopaenia and a potential risk of major haemorrhage.