title: Mechanism of anaemia in experimental bacterial endocarditis.
abstract: Rabits with Streptococcus viridans aortic valve endocarditis develop anaemia and reticulocytosis which increase with the duration of infection. Mean red cell counts decreased from 6.05 +/- 0.29 X 10(6) per mul before infection to 4.10 +/- 0.18 X 10(6) per mul after 11 to 20 days of endocarditis and reticulocytes increased from 1.16 +/- 0.14 X 10(5) per mul to 4.91 +/- 0.83 X 10(5) per mul after more than 20 days of endocarditis. The anaemia could not be explained by intravascular haemolysis. Anti-erythrocyte antibodies were not detected. Splenomegaly was a consistent finding and also increased with the duration of infection. Red cell half life (T1/2) was shortened to 4.7 +/- 0.3 days in rabbits with endocarditis compared with normal T1/2 of 11.1 +/- 0.5 days. The T1/2 of red cells from infected animals was prolonged when measured in noninfected rabbits and splenectomized animals had a mean red cell T1/2 of 9.25 days after three weeks of infection. These studies suggest that splenic enlargement associated with infection results in red cell sequestration, a mechanism not well recognized as contributing to the anaemia of endocarditis.
mesh_terms: D000740:Anemia / Q000097:blood / Q000209:etiology*; D000818:Animals; D004195:Disease Models, Animal; D004697:Endocarditis, Bacterial / Q000097:blood / Q000150:complications*; D004905:Erythrocyte Aging; D004906:Erythrocyte Count; D006207:Half-Life; D006400:Hematocrit; D006461:Hemolysis; D009929:Organ Size; D011817:Rabbits; D012156:Reticulocytes; D013154:Spleen / Q000033:anatomy & histology; D013290:Streptococcal Infections / Q000097:blood / Q000150:complications*