Spleen Flashcards
Spleen produces most of which immunoglobulin?
IgM
Difference between red and white pulp?
Red pulp (85%) filter for damaged RBCs (Pitting = removal of abnormalities in RBC membrane, i.e. Howell-Jolly bodies, Heinz bodies; Culling = removal of less deformable RBCs) and White pulp (15%) immunologic function (bacterial clearance, clearance of particles/debris)
What is tuftsin? What is properdin?
Opsonin, facilitates phagocytosis; Activates alternate complement pathway, produced in spleen
How common are accessory spleens? Where are they most commonly found?
20% of population, most often at splenic hilum
What is the pathophysiology of ITP? Treatment?
Drugs, viruses; Caused by anti-platelet IgG antibodies, resulting in decreased platelets, spleen is normal sized; in adults more common women, in children same; ITP usually resolves spontaneously in children <10, otherwise tx w/ steroids, IVIG if steroid resistant; in refractory cases splenectomy (80% respond after splenectomy)
What is the pathophysiology of TTP? Treatment?
Associated with medical reactions, infections, inflammation, autoimmune disease (HUS, ADAMTS13) assoc. with loss of platelet inhibition which leads to thrombosis/infarction, profound thrombocytopenia, tx w/ plasmapheresis (primary) immunosuppression; death due to intracerebral hemorrhage or ARF
Post-splenectomy sepsis syndrome: more common in what population? Most common organisms?
Most common in children (0.1% after splenectomy), higher for splenectomy for hemolytic dz (thalassemia major and sickle cell dz) or malignancy; S. pneumoniae #1, H. influenzas, N. meningitidis - try to wait until children >5
Spherocytosis/elliptocytosis - what is deficient, lab findings, symptoms, and treatment?
Spherocytosis most common congenital hemolytic anemia requiring splenectomy (autosomal dominant); spectrin defect (membrane protein), causes pigmented stones, anemia, splenectomy and cholecystectomy (after age 5); elliptocytosis is a spectrin and protein 4.1 deficit (otherwise similar); Lab findings - Coombs test is negative, mild-moderate anemia, low MCV, elevated RBC width, elevated retics/LDH/unconj. bili, leg ulceration is common
Most common congenital hemolytic anemia not involving membrane protein that require splenectomy?
Pyruvate kinase deficiency
Hodgkin’s lymphoma: staging, what cells are seen, best/worst prognosis?, most common type
type A asymptomatic, type B symptomatic (“B symptoms”) worse prognosis; stage II is 2 non-continuous areas on on same side of diaphragm, stage III involves each side of diaphragm, stage IV is liver/bone/lung or any non lymphoid tissue except spleen, see Reed-Sternberg cells; lymphocyte depleted worse prognosis, lymphocyte predominant best prognosis, nodular sclerosing is most common type – tx w/ chemo
Most common cause of splenic artery/vein thrombosis?
Pancreatitis
Most common splenic tumor?
Hemangioma, splenectomy if symptomatic
Most common malignant splenic tumor?
Non-Hodgkin’s lymphoma
What is Felty’s syndrome?
RA, hepatomegaly, splenomegaly, caused by WBC coated with immune complexes, antibodies vs neutrophil nuclei; leads to neutropenia – TX steroids (to improve neutropenia) splenectomy for symptomatic splenomegaly
How do you manage splenic abscess?
Splenectomy usually; high bleeding risk w/ perc drainage
What is a wandering spleen?
Spleen that lacks normal peritoneal attachments, has an unusually long pedicle, dx by CT, can cause splenic torsion; tx w/ splenopexy if not infarcted
What are some features of splenic artery aneurysms? (most common in which population? imaging findings? indication for intervention? How do they rupture?)
Most common visceral artery aneurysm, 4x more common in women, usually arises in middle-distal portion of splenic artery, XR can show ring-like calcification in LUQ, size >2cm indication for intervention, most are true aneurysms, assoc. w/ double rupture phenomenon (initial bleed into lesser sac, then free peritoneal rupture)
Splenic angiosarcoma associations
Vinyl chloride, thorium dioxide
