September 2, 2015 - The Spleen

Question 1

Red Pulp

Answer 1

Takes up ~75% of the volume of the spleen. It is here where macrophages destroy red blood cells and recycle iron.

Question 2

White Pulp

Answer 2

It is here where the T cells interact with dendritic cells and circulating B cells.

Contains ~30% of the lympoid cells.

Question 3

Size of a Normal Spleen

Answer 3

Is about the size of your fist.

Question 4

Functions of the Spleen

Answer 4

• Removal of aged or abnormal blood cells
• Immune function (particularly against encapsulated organisms)
• Hematopoiesis in the fetus (and sometimes in adults)
• Reserve pool and storage site
• Recycling of iron

Question 5

Howell-Jolly Bodies

Answer 5

Contain nuclear remnants. Their presence indicates a damaged or absent spleen.

Question 6

Heinz Bodies

Answer 6

Contain denatured hemoglobin and are only visible with a special stain.

Can indicate G6PD deficiency, alpha-thalassemia, or hypospenism.

Question 7

Common Enscapsulated Bacteria

Answer 7

Important to vaccinate against these before the removal of the spleen.

• Streptococcus pneumoniae*
• Hemophilus influenzae B*
• Neisseria meningitidis*

Question 8

Spleen and Hematopoiesis

Answer 8

Normally only functions as a hematopoietic organ during the 2nd trimester of a fetus, however it can also act in this way in hemolytic anemia that is chronic. (eg. Thalassemia or bone marrow disease)

Question 9

Symptoms of Splenomegaly

Answer 9

• Usually none unless very large
• Pain or discomfort in LUQ
• Early satiety due to compression of stomach
• Pain referred to left shoulder

Question 10

Castell’s Sign

Answer 10

Last intercostal space on the left side.

Normally is resonant on inspiration and expiration.

In splenomegaly, is dull or becomes dull on inspiration.

Question 11

Splenomegaly Causes

Answer 11

1. Congestive
2. Infiltrative
3. Infectious
4. Inflammatory
5. Hemolytic Disease

Question 12

Congestive Splenomegaly

Answer 12

Engorgement and congestion in red pulp with increased vascularity and increased pooling.

Caused by portal hypertension. This can be due to cirrhosis, or non-cirrhotic PHTN.

Question 13

Hemolytic Disease and Splenomegaly

Answer 13

Increased macrophage function due to phagocytosis of abnormal cells.

Increased blood pooling.

Extramedullary hematopoiesis.

Question 14

Infection and Splenomegaly

Answer 14

Can be caused by many things, but in our society, the most common are viruses. Particularly EBV.

Question 15

Inflammatory Splenomegaly

Answer 15

Can be caused by many conditions. It is important to look for inflammatory markers and antibodies.

Question 16

Splenectomy Procedure

Answer 16

1. Laparoscopic. Very good most of the time, but not good for retaining structure if needed for pathology or a diagnosis.
2. Open laparotomy. Needed for large spleens, obese patients, multipkle prior surgeries, and to preserve spleen for pathology.