pathology of the spleen

accessory spleen

congenital anomaly where a small, round island of splenic tissue is typically located near the splenic hilum or possibly near the tail of the pancreas

sonographic appearance of an accessory spleen:

will appear isoechoic to the spleen

splenic cleft

congenital anomaly where the spleen appears to be divided by a hyperechoic line

asplenia

congenital absence of the spleen

polysplenia

congenital anomaly that leads to the development of multiple masses of splenic tissue

asplenia and polysplenia have been associated with what other conditions?

some complex cardiac malformations and the abnormal location of other organs → heterotaxia syndromes

wandering spleen

• extremely rare

• the splenic ligaments are absent or underdeveloped, thus allowing the opportunity for the spleen to be highly mobile and often positioned well into the lower abdomen

• can result in splenic torsion which can further lead to splenic infarction

what is the most common abnormality of the spleen?

splenomegaly

splenomegaly

enlargement of the spleen

normal measurement of the spleen:

should not exceed 12-13 cm in length and 6 cm in thickness in adults

as the spleen enlarges, what happens to its echogenicity?

it becomes more hypoechoic

what is the most common cause of splenomegaly?

portal HTN

other causes of splenomegaly include:

• trauma

• leukemia

• lymphoma

• a pediatric sickle cell anemia crisis

• granulomatous disease

• infections → endocarditis, AIDS and hepatitis

• Epstein-Barr infection

massive splenomegaly can lead to what other condition?

splenic rupture which can further lead to splenosis

clinical findings of splenomegaly:

• palpable, enlarged spleen

• hemolytic abnormalities → sickle cell anemia

• trauma

• infection

• hx of cirrhosis, trauma, leukemia, or lymphoma

• leukocytosis and/or elevated RBC count

• possible LUQ pain or discomfort

sonographic findings of splenomegaly:

• enlargement of the spleen to greater than 12-13 cm in length or 6 cm in thickness

• spleen extends beyond the inferior pole of the left kidney

true splenic cysts are also referred to as:

epithelial cysts

clinical findings of simple splenic cysts:

• asymptomatic

• pain can occur with hemorrhage

sonographic findings of simple splenic cysts:

• round

• smooth-walled mass

• anechoic mass

• posterior enhancement

splenic abscess

may be caused by staphylococcus aureus, streptococcus, or salmonella

a history of what condition increases the patient’s likelihood of developing a pyogenic abscess?

a history of bacteremia

disease processes that may lead to a splenic abscess include:

• bacterial endocarditis

• diverticulitis

• osteomyelitis

• pelvic infections

clinical findings of splenic abscesses:

• fever

• leukocytosis

• LUQ tenderness

• left flank or shoulder pain

• splenomegaly

sonographic findings of splenic abscesses:

• complex appearance

• may contain debris or gas → produces dirty shadowing or ring down

• can be completely hypoechoic

• fungal abscess may appear as small solid masses or have a target or bull’s-eye appearance

• color doppler will demonstrate increased flow around the mass but not within it

fungal splenic abscesses are often caused by:

Candida

a splenic infarct may be caused by:

• sickle cell disease

• bacterial endocarditis

• tumor embolization

• vasculitis

• lymphoma

clinical findings of a splenic infarct:

sudden onset of LUQ pain

sonographic findings of a splenic infarct:

• acute infarct → hypoechoic, wedge-shaped mass within the spleen

• chronic infarct → hyperechoic, wedge-shaped mass within the spleen

clinical findings of splenic trauma:

• blunt trauma to the LUQ

• severe LUQ pain

• decreased hematocrit level indicating active bleeding

sonographic findings of splenic trauma:

• acute hemorrhage → complex or hypoechoic

• middle stage → echogenic (with clot formation) or isoechoic

• later stages of hemorrhage → anechoic or hypoechoic

• chronic hematomas may have a complex appearance of calcified walls

• a laceration may be noted as an echogenic line within the spleen immediately following trauma

what is the most common benign tumor of the spleen?

hemangioma

clinical findings of a splenic hemangioma:

• asymptomatic

• pain occurs with hemorrhage

sonographic findings of a splenic hemangioma:

well-defined, hyperechoic mass

clinical findings of granulomatous disease in the spleen:

• asymptomatic

• may have a hx of histoplasmosis, tuberculosis, or sarcoidosis

sonographic findings of granulomatous disease in the spleen:

small, echogenic foci that may shadow

splenic hamartoma

a benign mass that is associated with Beckwith-Wiedemann syndrome and tuberous sclerosis

clinical findings of splenic hamartoma:

• asymptomatic

• pain can occur with rupture

• patient may have a hx of Beckwith-Wiedemann syndrome or tuberous sclerosis

sonographic findings of splenic hamartoma:

• hypoechoic mass or masses → echotexture can vary however

• color doppler may reveal hypervascularity

angiosarcoma

exceedingly rare primary malignant tumor of the spleen

what is the most common malignancy of the spleen?

lymphoma

the presence of what type of cells indicates Hodgkin lymphoma?

Reed-Sternberg cells

what type of lymphoma is more common?

non-Hodgkin lymphoma

the most common primary locations for metastatic disease to the spleen are:

• breast

• lung

• skin → melanoma

• ovary

clinical findings of splenic malignancy:

• LUQ pain

• fever

• weight loss

• malaise

sonographic findings of splenic malignancy:

• diffuse → splenomegaly

• focal → hypoechoic masses

what type of lymphoma has a better chance of recovery?

Hodgkin lymphoma

splenic lymphangioma (pediatric)

• a benign lesion that is a congenital malformation of the lymphatic system

• comprised of both lymphatic and blood vessels

• most identified in children

clinical findings of splenic lymphangioma:

• nausea

• LUQ pain

• abdominal distention

sonographic findings of splenic lymphangioma:

• multicystic masses

• masses may contain hypoechoic or anechoic locules and hyperechoic septations

sickle cell disease

a group of inherited blood disorders that affects hemoglobin

sickle cell anemia (pediatric)

• patients have abnormal, crescent-shaped RBCs that tend to attach to each other and obstruct normal vascular channels, causing many clinical complications

• enlarged spleen

• occasionally, focal masses of normal splenic tissue may be noted

• recurrent sickle cell crises leads to the spleen becoming fibrotic and atrophy

patients undergoing a sickle cell crisis may have:

• decreased hematocrit

• complain of bone pain

• increased risk for gallstones, multiple organ damage, blindness, and stroke