34 Spleen ANATOMY AND PHYSIOLOGY

Spleen and Related Conditions

• The spleen receives blood supply from the splenic artery.
• The white pulp in the spleen functions as a lymphoid tissue, producing immune cells.
• IgM is the largest producer of antibodies in the spleen.
• The short gastrics and splenic artery supply the spleen with oxygenated blood.

Immune Function in the Spleen

• Dendritic cells/macrophages interact with helper T cells in the spleen, facilitating immune responses.

Red Pulp Function

• The red pulp in the spleen filters the blood, removing old or damaged red blood cells and recycling iron.

Platelet Reservoir

• The spleen serves as a reservoir for platelets.

Congenital Conditions

• The most common congenital lack of ligaments holding the spleen in place is wandering spleen.

Idiopathic Thrombocytopenic Purpura (ITP)

• The primary treatment for ITP is corticosteroids.

Thrombotic Thrombocytopenic Purpura (TTP)

• TTP is caused by a deficiency of ADAMTS13, a metalloprotease.

Post-Splenectomy Sepsis Syndrome (PSSS)

• Hereditary spherocytosis is associated with a 0.1% risk of developing PSSS.

Acquired Immune Hemolytic Anemia

• The treatment for warm antibody-type acquired immune hemolytic anemia is corticosteroids and rituximab.

Thalassemia

• The most common thalassemia is HbF-Bart's, characterized by persistent HgbF.

Hodgkin's Disease

• Lymphocyte-predominant cells are seen in Hodgkin's disease.

Hereditary Spherocytosis

• A deficit of spectrin, a membrane protein, leads to less deformable RBCs and splenic culling/sequestration.

Non-Hodgkin's Lymphoma

• Mantle cell lymphoma is generally associated with the worst prognosis.
• Diffuse large B-cell lymphoma is the most common type of non-Hodgkin's lymphoma.

Malignant Spleen Tumors

• Lymphoma is the most common malignant splenic tumor.

Felty's Syndrome

• Felty's syndrome is associated with rheumatoid arthritis, splenomegaly, and neutropenia.

Chylous Ascites

• The most common cause of chylous ascites is trauma.

Lymphoma Workup

• The recommended workup for lymphoma includes CT scans, PET scans, and bone marrow biopsies.

Howell-Jolly Bodies

• Howell-Jolly bodies are often seen in hereditary spherocytosis.

Splenectomy

• Hereditary spherocytosis rarely requires splenectomy.

Hemolytic Anemia

• Hemolytic anemia and decreased platelets can occur due to splenomegaly.

Benign Spleen Tumors

• Hemangioma is the most common benign splenic tumor.

Splenic Artery or Vein Thrombosis

• The most common cause of splenic artery or splenic vein thrombosis is pancreatitis.

Low Attenuation Fluid Collection

• A low attenuation fluid collection in the lesser sac/postsplenectomy space can occur due to a pseudocyst.