Color Atlas of Hematology - Practical Microscopic and Clinical ...

152Erythrocyte and Thrombocyte AbnormalitiesHyperchromic AnemiasIn patients with clear signs of anemia, e.g., a “sickly pallor,” atrophic lingualmucosa, and sometimes also neurological signs of bathyanesthesia(loss of deep sensibility), even just a cursory examination of the bloodsmear may indicate the diagnosis. Marked poikilocytosis and anisocytosisare seen, and the large size of the erythrocytes is particularly conspicuousin comparison with the lymphocytes, whose diameter they exceed (megalocytes).These are the hallmarks of macrocytic, and, with respect to bonemarrow cells, usually also megaloblastic anemia, with a mean cell diametergreater than 8 µm and a cell volume (MCV) usually greater than100 µm 3 . Mean cell Hb content (MCH) is more than 36 pg (1.99 fmol) andthus indicates hyperchromic anemia.Only when there is severe pre-existing concomitant iron deficiency is acombination of macrocytic cells and hypochromic MCH possible (“dimorphicanemia”).Table 26Most common causes of hyperchromic anemiasVitamin-B 12 deficiencyNutritional deficits, e. g.– Goat milk– Vegetarian diet– AlcoholismImpaired absorption– Genuine pernicious anemia– Status after gastrectomy– Ileum resection– Crohn disease– Celiac disease, sprue (psilosis)– Intestinal diverticulosis– Insufficiency of the exocrine pancreas– Fish tapewormFolic acid deficiencyNutritional deficits– Chronic abuse of alcoholImpaired absorption– E.g., sprue (psilosis)Increased requirement– Pregnancy– Hemolytic anemiaInterference/antagonism– Phenylhydantoin– Cytostatic antimetabolic drugs– Trimethoprim (antibacterialcombination drug)– Oral contrazeptives– Antidepressants– AlcoholAlthough other rare causes exist (Table 26), almost all patients with hyperchromicanemia suffer from vitamin B 12 and/or folic acid deficiency.Since a deficiency of these essential metabolic building blocks suppressesDNA synthesis not only in erythropoiesis, but in the other cell series aswell, over time more or less severe pancytopenia will develop.