HEMATOLOGY - splenomegaly

Question 1

what is the spleen? what are it’s functions?

Answer 1

spleen is part of the mononuclear phagocyte system + in the LUQ

4 main functions:
1. phagocytosis of blood cells & bacteria – mononuclear phagocyte system removes thru filtration
2. antibody production – rich supply of lymphocytes, monocytes & stored antibodies
3. hematopoiesis: makes RBC during fetal development
4. sequestration of formed blood elements: stores 300 mL of blood + 1/3 of plates

Question 2

what is splenomegaly? what can it cause? its risks?

Answer 2

associated with disease states
- can be present without underlying disease
- cause HYPERSPLENISM: norm functions of sleep get overactive –> anemia, leukopenia, & thrombocytopenia
- risk of: splenic rupture

Question 3

what are the causes of splenomegaly? how does this intertwine with its pathophysiology?

Answer 3

there are acute & chronic causes that lead to –> inflammation or infection –> enlargement bc of increase demand for defensive activities against infection causes

Question 4

what are the acute causes of splenomegaly?

Answer 4

• viral: hepatitis, infectious mononucleosis & cytomegalovirus
• bacterial: salmonella, gram negative
• parasitic: typhoid

Question 5

what are the subacte/chronic causes of splenomegaly?

Answer 5

• bacterial: subacute bacterial endocarditis & tuberculosis
• parasitic: malaria
• fungal: histoplasmosis
• felty syndrome, systemic lupus erythematosus, rheumatoid arthritis

Question 6

what are some other causes of splenomegaly?

Answer 6

congestive: back up of blood into spleen
- cirrhosis, HF, portal vein obstruction (portal hypertension), & splenic vein obstruction

infiltrative: macrophages with indigestible materials associated with storage diseases

tumor or cysts: cause actual growth of spleen

Question 7

what are the clinical manifestations of splenomegaly?

Answer 7

sequestering RBCs, granulocytes & platelets –> reduced all circulating blood cells –> accelerates their cells (esp RBCs, some WBC & plates) destruction
- up to 50% of RBC population –> disturbs normal physiologic concentration of RBC in circulation –> ANEMIA
- more sequestering = increase risk of rupture

Question 8

what kind of lab data would we see in someone with splenomegaly?

Answer 8

• some degree of anemia: low RBCs, Hgb, HCT
• leukopenia: low WBC
• thrombocytopenia: low plates
• pancytopenia: anemia, leukopenia & thrombocytopenia

Question 9

what is the disease trajectory of splenomegaly? treatment?

Answer 9

main treatment: splenectomy
- can so surgical repair if rupture but can cause infection + sepsis
- if splenectomy –> pt can resume normal activities

blood cell abnormalities after splenectomy
- RBCs thinner, broader, & wrinkled
- WBC count increase & plateaus
- plates rise after surgery & stabilizes
–> higher risk of infection –> keep up with vaccinations

Question 10

what is a rare post op complication after a splenectomy? how do we prevent this? what are its characteristics?

Answer 10

postsplenectomy infection (OPSI) syndrome
- can happen 3 yrs after splenectomy due to infection
- can progress to septic shock & DIC (disseminated intravascular coagulation)

characterized by:
- generalized non specific flu like symptoms –> rapid clinical deterioration
- progresses to septic shock & DIC

prevention:
- up to date with vaccinations
- medical attention for infections for prompt treatment