Review Question - QID 217676

This otherwise healthy patient who underwent an abdominal operation in the context of a motor vehicle collision has Howell-Jolly bodies on peripheral smear as a result of previous splenectomy.

Howell-Jolly bodies are nuclear remnants in erythrocytes that can be found in various pathological states; most commonly they are found in patients with absent or impaired function of the spleen. Since a function of the spleen is to filter abnormal or damaged erythrocytes and remove these intracellular inclusions, patients with non-functioning or absent spleens lack this ability, and erythrocytes with Howell-Jolly bodies continue to circulate. The etiologies for hyposplenism are many and can include causes such as post-splenectomy, sepsis, congenital disorders (such as congenital asplenia, Ivermark syndrome), sickle cell hemoglobinopathies, alcoholism, lupus, and post-bone marrow transplantation.

Marques et al. investigate the use of an experimental autogenic splenic implant model in the hopes to preserve splenic function after splenectomy, with function as measured by clearance of Howell-Jolly bodies.

Figure/Illustration A show a peripheral smear with the finding of Howell-Jolly bodies in a red blood cell on peripheral smear, indicated by the black arrows. Howell-Jolly bodies are nuclear remnants.

Incorrect Answers:
Answer 1: Congenital asplenia may lead to the presence of Howell-Jolly bodies, but this condition is very rare. As such, it is difficult to calculate its prevalence, though some estimates place the prevalence around 1 per 2 million newborns.

Answer 2: G6PD (glucose-6-phosphate dehydrogenase) deficiency is an inherited condition leading to premature breakdown of erythrocytes, causing hemolytic anemia. It is associated with Heinz bodies, which are inclusions within erythrocytes made of denatured hemoglobin.

Answer 4: Sickle cell anemia can lead to the development of functional asplenia over time. Though the process is not well understood, the current working hypothesis is that entrapment of abnormal erythrocytes in the spleen followed by splenic infarction eventually leads to hyposplenism and functional asplenia. Symptoms of sickle cell disease can include episodes of pain or pain crises typically involving the chest, abdomen or joints, swelling of the hands and feet, and frequent infections secondary to hyposplenism.

Answer 5: Splenic vein thrombosis is most often associated with chronic pancreatitis, and less commonly with malignancy or trauma. Chronic inflammation of the pancreas in close proximity to the splenic vein can cause thrombosis. In some cases, the mechanical pressure of a neighboring pancreatic pseudocyst can have the same effect.

Bullet Summary:
The presence of Howell-Jolly bodies is an indicator of splenic dysfunction.