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Name two end arteries:
splenic artery and short gastrics
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Whats the relationship between splenic vein and artery
splenic vein is posterior and inferior to splenic artery
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Red Pulp
- 1) 85% of spleen
- 2) acts as a filter for aged/damaged RBCs
- 3) Pitting: removal of abnormalities in RBC membrane
- 1- Howell Joley bodies- nuclear remnants
- 2- Heinz Bodies- hemoglobin
- 4)Culling- removal of less deformable RBCs
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White Pulp
- 1) 15%
- 2) immunologic function; contains lymphocytes and macrophages
- 3) Major site of bacterial clearance that lacks preexisting antibodies4) Site of removal of poorly opsonized bacteria, particles, and cellular debris5) Antigen processing occurs with interaction between macrophages and helper T cells
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Tuftsin
an opsonin; facilitates phagocytosis--> produced in spleen
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properidin
activates alternative complement pathway --> produced in spleen
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Hematopoesis
occurs in spleen before birth and in conditions like myeloid dysplasia
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Accessory spleen
most commonly found at splenic hilum (20%)
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Indications for splenectomy
- 1) ITP far greater than for TTP
- 2) ITP most common nontraumatic condition requiring splenectomy
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Normal Hematologic Functions of the spleen:
- 1) Culling or destruction of senescent erythrocytes
- 2) Pitting or removal of cytoplasm inclusive in erythrocytes
- 3) Reservoir for platelets and granulocytes
- 4) Hematopoesis- as fetus or in conditions with bone marrow destruction
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Normal Immunological Functions of the spleen:
- 1) filtration and trapping of circulatory antigens
- 2) lymphocytic stimulation and proliferation
- 3) antibody production in germinal follicles
- 4) production of opsonin-tuftsin and properdin
- 5) Opsonins: tuftsin and properdin
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Idiopathic Thrombocytopenia Purpura (ITP)
- 1) this can occur from many etiologies -drugs, viruses, etc.2) antiplatelet antibodies (IgG)- bind platelets, cause decrease in platelets
- 3) Petechiae, gingival bleeding, bruising, soft tissue ecchymosis
- 4) Spleen is normal
- 5) In children <10 years, usually resolves spontaneously
- 6) Treatment:
- 1- steroids (primary therapy)
- 2- plasmapheresis
- 3- gamaglobulin for steroid-resistant disease
- 4- Spleenectomy indicated for those who fail steroids --> removes IgG production and source of phagocytosis; 80% respond after splenectomy
- 5- give platelets 1 hr before surgery
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Thrombotic Thrombocytopenic Purpura (TTP)
1) associated with medical reactions, infections, inflammation, autoimmune disease
2) Loss of platelet inhibition- leads to thrombosis and infarction, profound thrombocytopenia
3) Purpura, fever, mental status changes, renal dysfunction, hematuria, hemolytic anemia
4) 80% respond to medical therapy
- 5) Treatment:
- 1- plasmapheresis (primary)2- steroids
- 3- ASA
6) Death is most commonly caused by intracerebral hemorrhage or acute renal failure
7) Splectomy is rarely indicated
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Postspelenectomy sepsis syndrome
- 1) 0.1% risk; increased risk in children2) S. pneumonia (#1), H. influenza, N. meningitidis- most common
- 3) Secondary to specific lack of immunity (immunoglobulin, IgM) to capsulated bacteria
- 4) Highest in patients with splenectomy for hemolytic disorders or malignancy5) Children also have increased risk of mortality after PSSS
- 6)Try to wait at least until 5 years old before performing splenectomy --> allows antibody formation; children can get fully immunized
- 7) Most episodes occur within 2 years of splenectomy
- 8) Children <10 years should be given prophylactic antibiotics for 6 months (controversial)
- 9) vaccines needed before splenectomy- pneumococus, meningococcus, H. influenzae
- -try to give before splenectomy
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Postsplenectomy changes
- 1) increased WBCs
- 2) increased RBCs
- 3) increased platelets (if platelets > 1x 106, need ASA)
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Hemangioma
- 1) #1 splenic tumor overall; #1 benign splenic tumor
- 2) splenectomy if symptomatic
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Whats the #1 malignant splenic tumor?
Non-hodgkin's lymphoma
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Splenic cysts
surgery if symptomatic or >10cm
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Hypersplenism
1) Results in: decreased platelets, RBCs, and WBCs, splenomegaly occurs as well.
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Definition of Hypersplenism
1) Decrease in circulating cell count of erythrocytes and/or platelets, and/or leukocytes
AND
2) Normal compensatory hematopoietic responses present in bone marrow
AND
3) Correction of cytopenia by splenectomy
with or without splenomegaly
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Secondary Hypersplenism (most common)
- Associated most commonly with:
- 1- increased venous pressue (portal hypertension, CHF)
- 2- malignant disease (leukemia)
- 3- chronic inflammatory disease (Felty's syndrome, SLE, sarcoidosis)
- 4- myeloproliferative disease
- 5- infectious disease
- 6- amyloidosis
- 7- hemolytic anemias
- 8- polycythemia vera
2) Splenectomy may be indicated for symptomatic hypersplenism associated with CLL, CML, NHL, Hodgkin's, hairy cell leukemia, hemolytic anemias, sarcoidosis
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Primary hypersplenism (very rare)
1) need to rule out other causes
2) splenectomy indicated for primary hypersplenism
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Sarcoidosis of spleen
1) anemia, decreased platelets
2) Treatment: splenectomy for symptomatic splenomegaly
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Felty's syndrome
- 1) rheumatoid arthritis
- 2) splenomegaly
- 3) hepatomegaly
Treatment: splenectomy for symptomatic splenomegaly
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Gaucher's disease:
1) lipid metabolism disorder leading to splenomegaly
2) partial splenectomy may be effective
- Gaucher's disease (pronounced /ɡoʊˈʃeɪz/)
- is a genetic disease in which a fatty substance (lipid) accumulates in
- cells and certain organs. Gaucher's disease is the most common of the lysosomal storage diseases.It is caused by a hereditary deficiency of the enzyme glucocerebrosidase. The enzyme acts on a fatty substance glucocerebroside
- (also known as glucosylceramide). When the enzyme is defective,
- glucocerebroside accumulates, particularly in white blood cells (mononuclear leukocytes). Glucocerebroside can collect in the spleen, liver, kidneys, lungs, brain and bone marrow.
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Hemolytic Anemias- membrane Protein Defects:
Spherocytosis:
1) most common congenital hemolytic anemia requiring splenectomy
2) spectrin deficit (membrane protein) deforms RBCs and leads to splenic sequestration
3) causes pigmented stones, anemia, reticulocytosis, jaundice, splenomegaly
4) try to perform splenectomy after age 5; give immunizations first
5) Treatment: splenectomy and cholecystectomy
6) splenectomy curative
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Hemolytic anemias- membrane protein defects
Elliptocytosis:
- Elliptocytosis:
- 1) symptoms and mechanism similar to spherocytosis; less common
2) spectin and protein 4.1 deficit (membrane protein)
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Hemolytic Anemias- Non-Membrane protein defects
- 1) Pyruvate kinase deficiency
- 1- results in congenital hemolytic anemia
- 2- causes altered glucose metabolism; RBC survival enhanced by splenectomy
- 2) Most common congenital hemolytic anemia not involving membrane protein that requires splenectomy
- 2) G6PD deficiency
- 1- precipitated by infection, certain drugs, fava beans
- 2- splenectomy usually not required
- 3)Warm antibody type acquired hemolytic anemia
- 1- indication for splenectomy
- 4) Sickle cell anemia
- 1- HgbA replaced with HgbS
- 2- spleen usually autoinfarcts and splenectomy not required
- 5) Beta thalassemia
- 1- most common thalassemia
- 2- Major- both chains affected; minor-1 chain, asymptomatic
- 3- Persistent HgbF
- 4- splenectomy may decrease hemolysis and symptoms
- 5- most die in teens secondary to hemosiderosis
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Hodgkin's Disease:
- A- asymptomatic
- B- Symptomatic (night sweats, fever, weight loss) --> unfavorable prognosis
- Stage I- 1 area or 2 contiguous areas on the same side of the diaphragm
- Stage II- 2 noncontiguous areas on the same side of the diaphragm
- Stage III- involved on each side of the diaphragm
- Stage IV- liver, bone, lung, or any other nonlymphoid tissue except spleen
- 1) see Reed-Sternberg cells2) lymphocyte predominant- best prognosis
- 3) Lymphocyte depleted- worst prognosis
- 4) Nodular sclerosis- most common
- 5) Treatment- XRT and chemotherapy with
- 1- vincristine
- 2- cyclophosphamide
- 3- prednisone
- 4- procarbazine
5) most common cause of chylous ascites- lymphoma
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Non-Hodgkin's lymphoma
- 1) worse prognosis than hodgkin's
- 2) generally systemic disease by the time diagnosis is made
- 3) 90% are B cell lymphomas
- 4) XRT and chemotherapy with
- 1- vincristine
- 2- cyclophosphamide
- 3- predinisone
- 4- adriamycin
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hairy cell leukemia
- Treatment:
- 1- splenectomy
- 2- IFN-gamma
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Spontaneous splenic rupture
- 1- mononucleosis
- 2- malaria
- 3- sepsis
- 4- sarcoid
- 5- leukemia
- 6- polycythemia vera
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splenosis
splenic implants, usually related to trauma
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Whats the most common cause of splenic artery or vein thrombosis
pancreatitis
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splenic artery aneurysms
- 1- females
- 2- secondary to fibromuscular dysplasia
- 3- atherosclerosis
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