1/8. Subglottic stenosis secondary to extramedullary hematopoiesis in a patient with postpolycythemia myeloid metaplasia.BACKGROUND: Extramedullary hematopoiesis (EMH) is known to occur in myeloproliferative disorders and hemoglobinopathies and is usually seen in the spleen and liver. methods: We report the first case of EMH causing subglottic stenosis in a woman with postpolycythemia myeloid metaplasia (PPMM). A tracheotomy was performed to maintain the airway and local radiotherapy was given. RESULTS: Two months after the radiotherapy was completed laryngoscopy showed an unobstructed airway with no evidence of disease, and the patient was successfully decanulated. magnetic resonance imaging 8 months after radiotherapy confirmed the absence of local disease. CONCLUSION: Consideration should be given to EMH as a possible cause of airway obstruction in the differential diagnosis of a patient with a history of PPMM.- - - - - - - - - - ranking = 1keywords = spleen (Clic here for more details about this article) |
2/8. diagnosis of polycythemia vera in an anemic patient.Criteria proposed by the polycythemia vera Study Group (PVSG) as well as several derived algorithms are currently used for the diagnosis of polycythemia vera. Although these guidelines have significantly enhanced diagnostic accuracy, they uniformly consider erythrocytosis as the requisite premise for instigating the subsequent workup. We describe the unusual presentation of a patient with microcytic anemia in whom the diagnosis of polycythemia vera was reached using the PVSG criteria and confirmed by in vitro culture assay of erythroid progenitor cells. This case highlights the usefulness of the PVSG criteria, including the red cell mass determination, for the diagnosis of polycythemia vera even in anemic patients. The roles of spleen red cell pooling and plasma volume expansion as major determinants of this unusual presentation are discussed.- - - - - - - - - - ranking = 1keywords = spleen (Clic here for more details about this article) |
3/8. Familial and congenital polycythemia in three unrelated families.Three families with polycythemia inherited through apparently different modes are described. Secondary causes of polycythemia were ruled out. erythropoietin (EPO) levels were normal or low, even after phlebotomy. in vitro erythroid colony growth in standard assay cultures containing EPO was normal; however, in the absence of added EPO, a few progenitors from most of the affected individuals were able to generate recognizable colonies of mature erythroblasts, although these were smaller and proportionately less numerous than seen in polycythemia vera (PV). To search for EPO-receptor changes as a possible pathophysiologic mechanism, we examined, by Southern blot analysis, genomic dna samples from affected and nonaffected family members, as well as three patients with PV. Two different probes, derived from the human EPO-receptor, were used. We found no evidence for chromosomal rearrangements or gene amplification in hereditary polycythemia or PV patients. Further, no nucleotide sequences were found that were homologous to the Friend spleen focus-forming virus glycoprotein gp55, which has been shown to bind to and activate the murine EPO-receptor. Functional studies examining number and binding affinity of the EPO-receptor on erythroid progenitors from three hereditary polycythemia patients demonstrated no abnormalities. We conclude that the mechanism(s) for the erythrocytosis in familial and congenital polycythemia and in PV may not involve the EPO-receptor and, therefore, may result from alterations of postreceptor responses.- - - - - - - - - - ranking = 1keywords = spleen (Clic here for more details about this article) |
4/8. Development of polycythaemia vera in a patient with myelofibrosis.In March 1981, a 53-year-old man presented with itching and was diagnosed as having myelofibrosis. There was gradual enlargement of the spleen over the following 5 yr. His spleen had to be removed in February 1986 because of physical discomfort. 3 months post-splenectomy he became polycythaemic. bone marrow examination was consistent with severe myelofibrosis. It was possible to demonstrate erythropoietin-independent BFU-E from peripheral blood, and ferrokinetic studies showed that erythropoiesis was localised to the liver with little bone marrow activity. Thus, despite severe marrow fibrosis, liver erythropoiesis was now polycythaemic, suggesting the coexistence of myelofibrosis and polycythaemia vera.- - - - - - - - - - ranking = 2keywords = spleen (Clic here for more details about this article) |
5/8. Primary proliferative polycythaemia without splenomegaly: a diagnostic problem.We report three cases of polycythaemia with no evidence of clinical splenomegaly and normal splenic red cell pool on isotope spleen scan. In each case, however, a diagnosis of primary proliferative polycythaemia (PPP) was suggested by in-vitro erythropoietin-independent growth of peripheral blood erythroid colonies. In one of these cases two possible causes of secondary polycythaemia were also identified. The use of investigations such as isotope spleen scanning and erythroid cell culture in helping to establish a diagnosis of PPP is discussed.- - - - - - - - - - ranking = 2keywords = spleen (Clic here for more details about this article) |
6/8. Autonomous erythropoietin induced erythrocytosis.Erythrocytosis in a young Sinhalese man is described. The patient was known to have had a raised Hb and PCV for at least 10 years. Subsequent investigations failed to support the diagnosis of polycythaemia vera or to reveal a cause for secondary polycythaemia. blood erythropoietin values were raised, but no cause for inappropriate secretion could be identified. Although there was no evidence of erythrocytosis in the family, the findings in this patient appear to be those of a condition which has been called familial polycythaemia. The spleen was unusually large and was associated with hypersplenism and thrombocytopenia. Problems of diagnosis and management are described. phlebotomy appears to be the treatment of choice, with a regimen of regular venesection for the control of symptoms due to hyperviscosity and vascular occlusion.- - - - - - - - - - ranking = 1keywords = spleen (Clic here for more details about this article) |
7/8. Polycythaemia following splenectomy in myelofibrosis with myeloid metaplasia. A reorganization of erythropoiesis.3 patients with myelofibrosis with myeloid metaplasia were splenectomized because of anaemia and disturbing splenomegaly. In the course of the 6 months following splenectomy, a polycythaemia developed. Erythrokinetic studies demonstrated that in all cases a reduction in plasma volume and an increase in red cell volume was obtained. Total erythropoiesis decreased along with normalization of ineffective erythropoiesis and peripheral haemolysis. The reappearance of an erythropoietic activity measured over the sacrum was a constant finding, while in 1 patient, a depression of activity over the liver was observed. The new distribution and organization of erythropoiesis in the splenectomized patients is hypothesized as being due to the removal of the influence of an enlarged spleen on erythropoietic organs.- - - - - - - - - - ranking = 1keywords = spleen (Clic here for more details about this article) |
8/8. erythropoietin-dependent erythrocytosis associated with hepatic angiosarcoma.erythropoietin (Ep) dependent erythrocytosis was discovered in a 77-year old man with angiosarcoma involving the liver and spleen. At autopsy, tissue from tumorous and normal sections of liver was obtained and extracts prepared for Ep assay in exhypoxic polycythemic mice. Neither tumor nor normal extracts had Ep activity; however, when the extracts were incubated with normal plasma prior to assay, significant amounts of Ep were generated. The normal liver tissue had three times the activity of the tumorous portion, 0.21 U/ml. These results suggest that the tissue contained an Ep activator, probably erythrogenin. It is proposed that the greater amount of erythrogenin activity in the normal tissue may reflect an attempt at liver regeneration following damage by an invading tumor, as regenerating liver has been identified as a stimulus for extrarenal EP and erythrogenin production.- - - - - - - - - - ranking = 1keywords = spleen (Clic here for more details about this article) |