Table of Contents
Definition / general | Terminology | Sites | Pathophysiology | Etiology | Case reports | Treatment | Microscopic (histologic) description | Peripheral smear images | Electron microscopy description | Differential diagnosisCite this page: Zhao X. RBC inclusions. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/bonemarrowhowelljollybodies.html. Accessed December 23rd, 2024.
Definition / general
Howell-Jolly bodies
- Basophilic nuclear remnants, i.e. clusters of DNA in circulating erythrocytes as well as erythroid precursors
- Named after William Henry Howell and Justin Marie Jolly (Am J Med Sci 2012;343:407)
Terminology
Howell-Jolly bodies
- Also called "micronucleated reticulocytes"
Sites
Howell-Jolly bodies
- Circulating erythrocytes
- Erythroid precursors in bone marrow
Pathophysiology
Howell-Jolly bodies
- During maturation in bone marrow, erythrocytes normally expel their nuclei but sometimes a small portion of DNA remains
- In healthy people, Howell-Jolly bodies are pitted out by spleen during erythrocyte circulation
Etiology
- Howell-Jolly bodies persist in those with functional hyposplenia or asplenia:
- Autosplenectomy due to sickle cell anemia
- Celiac disease (~10% have splenic atrophy)
- Hereditary spherocytosis
- Megaloblastic anemia
- Myelodysplastic syndrome (MDS)
- Radiation therapy
- Severe hemolytic anemia
- Splenectomy following trauma
Case reports
Howell-Jolly bodies
- 16 month old boy with congenital asplenia (Paediatr Child Health 2011;16:391)
- 60 year old man with Babesia (N Engl J Med 2003;349:2467)
- Patient with malignant histiocytosis (Acta Cytol 1988;32:680)
Treatment
Howell-Jolly bodies
- By itself, does not need to be treated
Microscopic (histologic) description
Howell-Jolly bodies
- Peripheral blood smear preparation with standard Wright-Giemsa stain shows smooth, round basophilic (purple) particles in eosinophilic erythrocytes
- Single Howell-Jolly bodies may be seen in megaloblastic anemia, hemolytic anemia, postsplenectomy
- Multiple Howell-Jolly bodies in a single cell usually indicates megaloblastic anemia or other abnormal erythropoiesis
Electron microscopy description
- EM confirms Howell-Jolly bodies are intracellular, located beneath red cell membrane, which have small circular membrane defect in their concavity beneath the membrane bulge (Arch Intern Med 1973;131:236)
Differential diagnosis
- Basophilic stippling (punctate basophilia):
- Irregular basophilic granules within erythrocytes, fine to coarse, deep blue with Wright stain, due to abnormal instability of RNA in young red cell
- Fine stippling is associated with increased polychromatophilia, increased production of red cells
- Coarse stippling is associated with lead poisoning, other diseases of impaired hemoglobin synthesis, megaloblastic anemia, other severe anemia
- Howell-Jolly-like bodies:
- Detached nuclear fragments in cytoplasm of neutrophils that resemble Howell-Jolly bodies
- Malarial stippling:
- Fine minute granules in enlarged erythrocytes that harbor Plasmodium vivax
- With Wright stain, these "Schüffner granules" stain purplish red; may be so numerous that they hide the parasites
- Pappenheimer bodies:
- Iron containing granules of siderocytes which may stain with Wright stain
- Usually few in number in a given red cell
- Less commonly seen in peripheral blood except after splenectomy
- Siderocytes:
- Red cells with inorganic iron containing granules, as demonstrated by Prussian stain for iron