Which of the following is NOT a location where accessory spleens can be found?
The most common anomaly of splenic embryology is the accessory spleen. Present in up to 20% of the population, one or more accessory spleen(s) may occur in up to 30% of patients with hematologic disease. Over 80% of accessory spleens are found in the region of the splenic hilum and vascular pedicle. Other locations for accessory spleens in descending order of frequency are: the gastrocolic ligament, the tail of the pancreas, the greater omentum, the greater curve of the stomach, the splenocolic ligament, the small and large bowel mesentery, the left broad ligament in women, and the left spermatic cord in men.
Which of the following splenic ligaments is NOT an avascular plane?
Of particular clinical relevance, the spleen is suspended in position by several ligaments and peritoneal folds to the colon (splenocolic ligament); the stomach (gastrosplenic ligament); the diaphragm (phrenosplenic ligament); the kidney, the adrenal gland, and the tail of the pancreas (splenorenal ligament) (Fig. below). Whereas the gastrosplenic ligament contains the short gastric vessels, the remaining ligaments are usually avascular, with rare exceptions, such as in a patient with portal hypertension. The relationship of the pancreas to the spleen also has important clinical implications. In cadaveric anatomic series, the tail of the pancreas has been demonstrated to lie within 1 em of the splenic hilum 75% of the time and to actually abut the spleen in 30% of patients.
Suspensory ligaments of the spleen
All of the following are functions of the spleen EXCEPT:
The spleen has both fast and slow circulation of blood. It is during slow circulation that blood travels through the reticular spaces and splenic cords where it is exposed to contact with splenic macrophages which remove senescent blood cells. Through this process the spleen is also able to remove erythrocyte inclusions such as Heinz bodies without lysing the cells. Through the reticuloendothelial system the spleen clears encapsulated bacteria such as pneumococcus and Haemophilus influenzae which are poorly opsonized from the hepatic reticuloendothelial system. In addition to these functions the spleen serves as an extramedullary site for hematopoiesis and plays a functional role in the recycling of iron. While the white pulp of the spleen is important in the initiation of the adaptive immune response, material is delivered to the spleen through the blood and not the lymph.
Which of the following proteins is not altered in hereditary spherocytosis (HS)?
The underlying abnormality in hereditary spherocytosis (HS) is an inherited dysfunction or deficiency in one of the erythrocyte membrane proteins (spectrin, ankyrin, band 3 protein, or protein 4.2), which results in destabilization of the membrane lipid bilayer. This destabilization allows a release oflipids from the membrane, causing a reduction in membrane surface area and a lack of deformability, leading to sequestration and destruction of the spherocytic erythrocytes in the spleen. Although less common than glucose-6-phosphate dehydrogenase (G6PD) deficiency overall, pyruvate kinase deficiency is the most common RBC enzyme deficiency to cause congenital chronic hemolytic anemia.
Splenectomy is indicated as a treatment in which of the following conditions?
Autoimmune hemolytic anemias (AIHA) are characterized by destruction ofRBCs due to autoantibodies against RBC antigens. AIHA is divided into warm and cold categories based on the temperature at which the autoantibodies exert their effect. In cold-agglutinin disease severe symptoms are uncommon and splenectomy is almost never indicated. Warm-agglutinin disease presents with mild jaundice as well as symptoms and signs of anemia with one-third to one-half of patients presenting with splenomegaly. Initial treatment is with corticosteroids with splenectomy being second-line therapy with failure of steroids. Although splenectomy has a 60 to 80% response rate recurrence is common. Hodgkin's disease is a disorder of the lymphoid system characterized by the presence of ReedSternberg cells. Most patients present with lympadenopathy above the diaphragm with adenopathy below the diaphragm rare on presentation. Adenopathy below the diaphragm can arise with disease progression and the spleen is often an occult site of spread although splenomegaly is uncommon. While splenectomy is performed for surgical staging in certain cases including clinical suspicion of lymphoma without evidence of peripheral disease or restaging for suspicion of failure after chemotherapy, staging laparotomy is less commonly performed in the current era of minimally invasive surgery and advanced imaging techniques. G6PD deficiency is the most common RBC enzyme deficiency and can be characterized by chronic hemolytic anemia, acute intermittent hemolytic episodes, or no hemolysis depending on the variant. Treatment for G6PD deficiency involves avoidance of drugs known to precipitate hemolysis. Treatment for splenic abscess involves initiation ofbroad-spectrum antibiotics with tailoring of antibiotic therapy once culture results become available as well as splenectomy. While splenectomy is the procedure of choice percutaneous or open drainage are options for patients unable to tolerate splenectomy.
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