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Query: UMLS:C0032463 (polycythemia vera)
 3,374 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Some routine red blood cell (RBC) measurements and indexes (count, mean volume, volume dispersion, and mean hemoglobin [HGB] concentration) can be used to differentiate iron deficiency from heterozygous beta-thalassemia. A number of formulas that incorporate two or more of these measurements have been described to amplify such differences. The H*1 hematology analyzer directly measures volume and HGB concentration of individual RBCs. We have assessed the diagnostic usefulness of conventional and new RBC measurements provided by the H*1 on a learning data set that comprised 119 patients with iron deficiency and 172 patients with beta-thalassemia trait, both untreated and uncomplicated. The most striking finding was the inverse behavior of percentages of microcytes (volume, less than 60 fL) and hypochromic RBCs (HGB concentration, less than 280 g/L) in the two conditions. In 162 of 172 patients with beta-thalassemia trait, the percentage of microcytes (mean, 33.1%; central 95th percentile range, 9.2% to 54.5%) was higher than the percentage of hypochromic RBCs (mean, 13.9%; central 95th percentile range, 1.7% to 24.7%). In 105 of 119 patients with iron deficiency, on the contrary, the percentage of hypochromic cells (mean, 34.6%; central 95th percentile range, 9.7% to 73.1%) was higher than the percentage of microcytes (mean, 12.8%; central 95th percentile range, 1.7% to 29.6%). The ratio between the percentage of microcytes and the percentage of hypochromic cells provided by the H*1 (microcytic-hypochromic ratio) was useful in differentiating the two types of microcytic anemia: with the use of a discriminant value of 0.9, the discriminant efficiency of the microcytic-hypochromic ratio was 92.4% (95% confidence interval, 88.8% to 95.2%), higher than that of the five previously described discriminant formulas and simple RBC measurements. When assessed on a test data set that comprised 149 unselected cases of microcytic anemia, a microcytic-hypochromic ratio lower than 0.9 demonstrated high sensitivity (94.0%), specificity (92.3%), and predictive value (94.0%) for the presence of iron-deficient erythropoiesis in patients with isolated iron deficiency, polycythemia vera treated by phlebotomy, and iron deficiency complicating heterozygous thalassemia. In conclusion, our results showed that iron-deficient erythropoiesis is characterized by the production of RBCs with a severely decreased HGB concentration, while microcytes of beta-thalassemia trait are generally smaller, with a more preserved HGB concentration. Such properties, as assessed by the H*1 hematology analyzer, are very useful in distinguishing these two common types of microcytic anemia.
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PMID:Automated measurement of red blood cell microcytosis and hypochromia in iron deficiency and beta-thalassemia trait. 173 38

A 77-year-old male having multiple small nevi over the lips, face, mucous membrane of mouth, tongue, neck and thorax was admitted to our hospital because of severe anemia. He has been diagnosed as Rendu-Osler-Weber disease (Osler's disease) since his 42 years of age. Although the stools were positive for occult blood, hematologic examination disclosed no abnormalities except for severe hypochromic and microcytic anemia. Gastrointestinal examination showed multiple stigmata in the esophagus, stomach, duodenum, and several tumors in the colon. Histological findings of biopsy specimens obtained from these tumors revealed adenocarcinomas and tubular adenomas. Surgical resection was carried out. Resected specimens showed two tumors (one is in ascending colon appeared to be 2 type carcinoma, 1.9 x 2.3 cm in size, another is in caecum, 3 type, 7.0 x 5.0 cm in size) and three Yamada-II approximately III type polyps. Pathohistologically, the tumor in ascending colon showed moderately differentiated adenocarcinoma, another one in caecum showed mucinous carcinoma, and polyps showed tubular adenomas, respectively. Unfortunately, the anemia of this case was regarded as stemming from Osler's disease, so the precise gastrointestinal examination was not performed for a long time. It should be emphasized to be faithful to the fundamentals of medical diagnosis.
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PMID:[A case of Rendu-Osler-Weber disease associated with simultaneous, multiple advanced cancers in the colon]. 770 55

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.
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PMID:Diagnosis of polycythemia vera in an anemic patient. 1092 62