Howell-Jolly bodies

The incidence of nuclear anomalies in bone marrow interphase cells significantly increased (p<0.05) in Chinese hamsters gavaged on 2 consecutive days with 2,500 and 5,000 mg/kg/day of Reofos 50 (Ciba-Geigy 1984a), but not in those dosed with 1,250 mg/kg/day. The types of anomalies used in scoring were single "Howell-Jolly" bodies, fragments of nuclei in erythrocytes, micronuclei in erythroblasts, micronuclei in leucopoietic cells, and polyploidal cells. 

Hematological Effects. Severe leukocytosis, with notable increases in immature polymorphonuclear cells, myelocytes, and myeloblasts and nucleated red cells and Howell-Jolly bodies, indicative of hemolytic anemia were observed in individuals after application of a salve that contained potassium chromate to treat scabies (Brieger 1920). Leukocytosis was also described in a case report of a man who was admitted to a hospital with skin ulcers on both hands due to dermal exposure to ammonium dichromate in a planographic printing establishment, where he had worked for a few months (Smith 1931). It should be noted that the man had a history of asthma. 

CBC analysis of an individual homozygous for Hb S indicates a moderate to a major decreased Hb level (60 to 100 g/L) with a normal to increased MCV and MCH. In individuals with a concurrent thalassemia, the Hb is farther decreased and both the MCV and MCH are lowered. In the neonate the peripheral blood smear shows the occasional sickle and target cells and Howell-Jolly bodies. As a patient s age increases, these features of hyposplenism become increasingly evident. In the adult the percentage of sickle cells observed can be as much as 30% to 40%. In the setting of a sickle cell crisis, fewer sickle cells may be present than when the individuals are clinically well. Howell-Jolly bodies, target cells, Pappenheimer bodies, boat-shaped cells, and nucleated RBCs are noted. The platelet count and neutrophil counts are elevated. Sometimes blister cells in which the Hb appears to be present in only one half of the cell is observed. 

Hematologic Howell-Jolly body-like inclusions have been observed in neutrophils in a transplant recipient in association with ganciclovir therapy in a 31-year-old man they disappeared after a few days of therapy [ll ]. The authors concluded that ganciclovir may cause nuclear fragmentation in such patients, but that a role of cytomegalovirus infection could not be excluded. 

Abdel-Monem H, Prakasam A, Thiagaraj an P. Howell-Jolly body-like inclusions in neutrophils of a transplant recipient in association with ganddovir therapy. Arch Pathol Lab Med 2010 134(6) 809-10. 

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