1/4. Hereditary thrombocythaemia is a genetically heterogeneous disorder: exclusion of TPO and MPL in two families with hereditary thrombocythaemia.Hereditary thrombocythaemia (HT) is an autosomal dominant disorder with clinical presentation and complications resembling sporadic essential thrombocythaemia (ET). Mutations in the thrombopoietin (TPO) gene causing overproduction of TPO and elevated TPO serum levels have been found previously in three families with HT. Here, we present evidence for genetic heterogeneity by demonstrating that HT in a Spanish and a US family is caused by genes other than TPO. Affected family members in both families had normal TPO serum levels. genetic linkage analysis with TPO microsatellite markers excluded TPO as the disease gene in the Spanish HT family, and sequencing of the TPO gene revealed no mutations in the propositus of the US family. To test a role for MPL, the gene for the TPO receptor, we identified three single nucleotide polymorphisms (SNP) and a novel polymorphic CA microsatellite marker. By linkage analysis, we excluded MPL as the cause of HT in the Spanish family. Interestingly, mapping of the CA microsatellite marker to a region 40.5 kb upstream of MPL revealed the presence of sequences from the TIE gene, which encodes a tyrosine kinase receptor expressed on megakaryocytes and endothelial cells. Thus, MPL and TIE are in close physical proximity, and the CA microsatellite described here will be a useful genetic marker for both genes.- - - - - - - - - - ranking = 1keywords = physical (Clic here for more details about this article) |
2/4. A case of pseudo-Bartter's syndrome associated with hypergastrinemia, thrombocytosis and increased serum thyroxine-binding globulin.A housewife, 40 years of age, was admitted with dysesthesia of the extremities, muscle weakness, and attacks of adynamia and thirst. She had been taking a laxative for more than 20 years. On physical examination, blood pressure was 94/56 mmHg. Laboratory tests revealed thrombocytosis, low serum K and marked increases in both plasma renin activity and serum aldosterone. serum TBG was increased. serum gastrin was also markedly increased and could not be enhanced by exogenous secretin. Both angiotensin 11 loading test and noradrenalin loading test failed to increase blood pressure. ammonium chloride loading to examine the disturbance of urinary acidification was abnormal in the short term test and borderline in the long term test. Following a diagnosis of pseudo-Bartter's syndrome induced by long term intake of laxative and repeated diarrhea, the administration of laxative was interrupted and potassium, indomethacin and spironolactone were administered. However, serum K remained low. Hypergastrinemia, thrombocytosis and a high serum TBG level also persisted, the causes of which remain unknown. This is the first reported case of pseudo-Bartter's syndrome associated with hypergastrinemia, thrombocytosis and increased serum TBG.- - - - - - - - - - ranking = 13.097899132535keywords = physical examination, physical (Clic here for more details about this article) |
3/4. Refractory anemia with an excess of blasts developed into overt leukemia with leukothrombocytosis.A 72-year-old man with refractory anemia with an excess of blasts developed overt leukemia with leukothrombocytosis. Hematological and physical findings closely resembled those of an accelerated or blastic phase of chronic myelocytic leukemia. The cytogenetic anomaly of i(17q) was observed during the course. The present case is suggestive of the diversities of myelodysplastic syndromes (MDS), including relationships between MDS and myeloproliferative disorders (MPD) and acute leukemia.- - - - - - - - - - ranking = 1keywords = physical (Clic here for more details about this article) |
4/4. An incidental finding of extreme self-limited thrombocytosis of unknown cause.This report describes an 11-year-old male who presented to his pediatrician at the Bowman Gray School of medicine in Winston-Salem, N.C., because of long standing enuresis. During evaluation and the following two-week period, this patient was found to have extreme thrombocytosis ranging from 2,175 x 10(9)/L to 3,700 x 10(9)/L. In the absence of any apparent reactive cause, a presumptive diagnosis of essential thrombocythemia was made. Although chemotherapy was considered, the patient was temporarily lost to follow-up before there was a final decision about therapy. One year later, this patient's platelet count had spontaneously decreased to normal (273 x 10(9)/L), and has remained normal during a follow-up period of seven years, although only sporadic platelet counts have been obtained. His most recent physical examination revealed no abnormalities. The case is presented as further evidence that extremely high platelet counts are not necessarily dangerous and do not all require therapy.- - - - - - - - - - ranking = 13.097899132535keywords = physical examination, physical (Clic here for more details about this article) |