Non-tropical idiopathic splenomegaly

Idiopathic splenomegaly: a previously unrecognised cause of anaemia and thrombocytopenia in a dog

Summary

A nine-year-old female neutered Old English sheepdog was referred for investigation and treatment of moderate, non-regenerative anaemia and thrombocytopenia. Aside from the aforementioned changes on complete blood count (CBC), the only abnormality found during diagnostic investigation was marked, generalised splenomegaly. A cause for the anaemia, thrombocytopenia and splenomegaly was not found following initial investigation. Splenectomy was performed and histopathological analysis showed marked, diffuse, subacute-chronic congestion and intraparenchymal haemorrhage. There was no evidence of neoplastic change. The splenic vasculature appeared normal during coeliotomy and torsion was not present. The findings of anaemia and thrombocytopenia, along with the histopathological changes found in the spleen, are similar to those found in people diagnosed with idiopathic splenomegaly. The dog recovered well from anaesthesia and was discharged the following day. Repeat CBCs over 12 months postsurgery showed results within normal limits, and no clinical signs had been reported by the owners.

Non-tropical idiopathic splenomegaly (Dacie's syndrome): report of 5 cases

We describe 5 patients, aged 22-69 years, with massive splenomegaly of unknown origin an features of hypersplenism. Splenectomy corrected the cytopenia(s) and abolished the symptoms in each case; the histological features of the spleen were non-specific and included congestive changes and lymphoid hyperplasia. 2 of these patients developed non-Hodgkin's lymphoma (NHL) 2 and 6 years after spenectomy. A total of 46 cases of splenomegaly of unknown origin have been reported from UK, USA, and Australia so far, and in 9, NHL developed 8 to 80 months after splenectomy. The questions relating to the pathogenesis of splenomegaly and the subsequent development of NHL remain to be answered. We propose that this 'entity' be known as Dacie's syndrome, after Sir John Dacie who characterised it in 1969.

Primary splenic hairy cell leukemia--remission for 21 years following splenectomy

A patient with primary splenic hairy cell leukemia is reported. This patient presented with massive splenomegaly and pancytopenia due to hypersplenism. Exploratory laparotomy failed to demonstrate any disease outside the spleen and splenic hilar lymph nodes. Splenectomy was the only form of treatment. During the following 21 years, no recurrent hairy cell leukemia has been found. This case allows speculation that hairy cell leukemia may originate in the spleen and that prolonged survival or cure of the disease after splenectomy alone may be due to removal of stem cells in the spleen.

Non-tropical 'idiopathic splenomegaly': a follow-up study of ten patients described in 1969

The later history is described of four of 10 patients who were reported in 1969 as suffering from non-tropical 'idiopathic splenomegaly'. Two of the four patients developed malignant lymphomas 6 years and 2 years, respectively, after splenectomy but the two other patients have lived for 17 and 15 years, respectively, without developing any signs of a malignant tumour. Thus, four of the original 10 patients have developed malignant's lymphomas. The histology of the patients' spleens has been reviewed in the light of their clinical history, but no criteria have been found which are of clear prognostic value. However, with hindsight it was possible to recognize some cytological abnormality in the spleens in three out of the four patients who developed malignant lymphomas, and it appears that unless the cell population in both the red and white pulp is strictly normal, the patient is likely to develop a malignant lymphoma. The tumours which subsequently developed showed no special or characteristic features. The title 'idiopathic splenomegaly' is clearly unsatisfactory but the alternative 'chronic lymphocytic lymphoma with hypersplenism', although appropriate for the illness of the patients who developed malignant lymphomas, is inappropriate for those in which the pathological process seems not to be neoplastic.