Spleen

Question 1

What is the size of a normal spleen? Moderate splenomegaly? Severe splenomegaly?

Answer 1

Normal spleen (not splenomegaly) = < 11cm in largest dimension Moderate splenomegaly : 11-20cm (some say > 13cm in craniocaudal height) Severe splenomegaly : >20cm

Question 2

What is massive splenomegaly?

Answer 2

When the spleen is 5 std dev above the mean normal volume, when the spleen reaches the iliac crest, longer than 18cm, crosses the midline or weights more than 1000-1500 g

Question 3

What are the ligaments to the spleen? Which ones are vascular and what vessels do they hold?

Answer 3

1) gastrosplenic (contains short gastrics and left gastroepiploic artery) 2) splenocolic 3) splenophrenic 4) splenorenal [aka. lienorenal ligament] (contains splenic artery, splenic vein, and tail of paincreas]

Question 4

What are some common causes of enlarged spleen?

Answer 4

Hereidtaroy spherocytosis Sickle cell disease thalassemia Hodgkins lymphoma & Non-Hodjkins lymphoma Acute myeloid leukemia, chronic myeloid leukemia, and chronic lymphocytic leukemia Glucose-6-phosphase dehydrogenase (G6PD) deficiency Immune (idiopathic) thromboctyopenic purpura

Question 5

What are some hematologic diseases associated with hemolytic anemia?

Answer 5

sickle cell disease beta thalassemia Hereditary spherocytosis

Question 6

What are the ethnic origins of some hematologic diseases associated with hemolytic anemia?

Answer 6

• Sickle cell disease = African descent - Beta thalassemia = Mediterranean, Southeast Asian, African - Hereditary spherocytosis = Northern european

Question 7

What is the inheritance pattern of the thalassemias?

Answer 7

autosomal dominant

Question 8

What is the inheritance pattern of hereditary spherocytosis?

Answer 8

autosomal dominant

Question 9

What is the inheritance pattern of G6PD deficiency?

Answer 9

x-linked recessive

Question 10

What is the inheritance pattern of sickle cell disease?

Answer 10

autosomal recessive

Question 11

What is a differential for patients with isolated thrombocytopenia?

Answer 11

heparin-induced thrombocytopenia viral infection cirrhosis pregnancy/preeeclampsia hypersplenism autoimmune disease thrombocytopenic purpura/hemolytic uremic syndrome ITP (diagnosis of exclusion)

Question 12

In a patient with hemolytic anemia, what are indications for splenectomy?

Answer 12

1) symptomatic splenomegaly/hypersplenism refractory to medical mangagement 2) ITP AND [refractory to steroids, platelet count < 10k for 6 weeks, pregnant women failed steroids/IVIG w/ plt < 10K or < 30K w/ bleeding] 3) hereditary spherocytosis

Question 13

What age do you perform splenectomy for hereditary spherocytosis?

Answer 13

> 5 y/o; Goal is to preserve immune function and reduce risk of splenectomy sepsis.

Question 14

For patients under going splenectomy, when do you vaccinate the patient? What do you vaccine them against?

Answer 14

• Vaccination 2 weeks prior to surgery or 2 weeks after surgery - Vaccinate against Haemophilus influenza type B, Streptococcus pneumoniae (pneumococcus), and Neisseria meningitides (menigococcus)

Question 15

What are the specific vaccinations for each of the organisms in the post-splenectomy vaccine prophylaxis?

Answer 15

o Streptococcus pneumoniae - Polyvalent pneumococcal vaccine (Pneumovax 23) o Haemophilus influenzae type B - Haemophilus influenzae b vaccine (HibTITER) o Neisseria meningitidis - Age 16-55: Meningococcal (groups A, C, Y, W-135) polysaccharide diphtheria toxoid conjugate vaccine (Menactra) - Age >55: Meningococcal polysaccharide vaccine (Menomune-A/C/Y/W-135)

Question 16

What is the route and when do you revaccinate each of the post-splenectomy vaccinations?

Answer 16

• Polyvalent pneumococcal 0.5 mL SC = Q6 years - Quadravalent meningococcal/diphtheria conjugate 0.5 mL IM upper deltoid = q3-5 years - Quadravalent meningococcal polysaccharide 0.5mL SC = q3-5 years - Haemophilus b conjugate 0.5 mL IM= NO revaccination required

Question 17

What is the new 2019 CDC pneumococcal vaccine recommendations for splenectomy in patients 19 to 65 y/o and > 65 y/o?

Answer 17

19 to 65 y/o: 1 dose PCV13 –> 1 dose PPSV23 at least 8 weeks later —> PPSV23 at least 5 years after previous PPSV23 Age 65 years or older: 1 dose PPSV23 at least 5 years after most recent PPSV23 (note: only 1 dose PPSV23 recommended at age 65 years or older)

Question 18

What is the new 2019 CDC pneumococcal vaccine recommendations for splenectomy in patients 2 to 5 yeas old and 6 to 18 years old?

Answer 18

history of 3 PCV13 doses: 1 dose PCV13 (at least 8 weeks after any prior PCV13 dose) history of less than 3 PCV13 doses: 2 doses PCV13 (8 weeks after the most recent dose and administered 8 weeks apart) No history of PPSV23: 1 dose PPSV23 (at least 8 weeks after any prior PCV13 dose) and a 2nd dose of PPSV23 5 years later

Question 19

What is the new 2019 CDC pneumococcal vaccine recommendations for splenectomy in patients 6 to 18 years old?

Answer 19

• No history of either PCV13 or PPSV23: 1 dose PCV13, 2 doses PPSV23 (dose 1 of PPSV23 administered 8 weeks after PCV13 and dose 2 of PPSV23 administered at least 5 years after dose 1 of PPSV23) - Any PCV13 but no PPSV23: 2 doses PPSV23 (dose 1 of PPSV23 administered 8 weeks after the most recent dose of PCV13 and dose 2 of PPSV23 administered at least 5 years after dose 1 of PPSV23) PPSV23 but no PCV13: 1 dose PCV13 at least 8 weeks after the most recent - PPSV23 dose and a 2nd dose of PPSV23 administered 5 years after dose 1 of PPSV23 and at least 8 weeks after a dose of PCV13

Question 20

What is the most common indication for open splenectomy? What are some clinical scenarios that would be favorable for a open splenectomy?

Answer 20

MC indication = trauma

Open is Preferred if: massive splenomegaly, ascites, portal hypertension, multiple prior opertasions, extensive splenic irradiation, and possible splenic abscess

Question 21

What are the advantages and drawback of performing a splenectomy laparoscopically?

Answer 21

• Gold standard for normal-sized spleens - Pros: Dec. intraoperative blood loss, shorter hospital LOS, lower morbidity - Cons: decreased operating space if any degree of splenomegaly

Question 22

What are the advantages of performing a hand-assisted splenectomy?

Answer 22

Pros: better for spleens > 22cm in craniocaudal length or 19cm width, decreased operative time if massive splenmgaly, no diff in LOS than laparoscopic

Question 23

Per AAST, what is a Grade I splenic injury?

Answer 23

• Subcapsular hematoms < 10% of surface area
• Capsular laceration < 1 cm in length

Note: multiple grade I injuries are graded as grade II

Question 24

Per AAST, what is a Grade II splenic injury?

Answer 24

• Subcapsular hematoma 10 to 50% of surface area
• Intraparechymal hematoma < 5cm in diameter
• Laceration 1-3 cm in depth not involving trabecular vessels

Note: multiple grade I injuries are graded as grade III

Question 25

Per AAST, what is a Grade III splenic injury?

Answer 25

- Subcapsular hematoma \> 50% of surface area or expanding - Intraparenchymal hematom a\> 5cm or expanding - Laceration \> 3cm in depth or involving trabecular vessesls - Ruptured subcapsular or parenchymal hematoma

Question 26

Per AAST, what is a Grade IV splenic injury?

Answer 26

Laceration involving segmental or hilar vessels with major devascularlization (\>25% of spleen)

Question 27

Per AAST, what is a Grade V splenic injury?

Answer 27

- Shattered spleen - Hilar vascular injury with splenic devascularization

Question 28

What are key steps for an open splenectomy?

Answer 28

Incision: midline (ruptured spleen/splenomegaly) vs. left costal margin (elective) 1) Mobilize the splee by dividing ligamentous attachments begnning with splenoolic ligament 2) Enter the lesser sac 3) If significant spenomegaly --\> early ligate the splenic artery along superior border of the pancreas [helps shrink spleen, safer dissectio nof hilum, autotransfusion of RBC /plt] 4) Incise lateral peritoneal attachments (splenophrenic legment) and dvelop plane deep to spleen and tail of pancreas 5) Individually ligate and ivide shot gastr vessels 6) Identify tail of pancreas and protect it (\< 1cm of splenic hilum) 8) Ligate spleniicartery and vein beore dividing 9) remove Spleen 10) look for accesory spleens 11) close abdinen w/o drainage

Question 29

Where are common locations for accesory spleens? Which is the most common?

Answer 29

Splenic hilum (MOST COMMON) splenic pedicle greater omentum tail of the pancreas splenocolic ligaments

Question 30

What is the incidence of postsplenectomy sepsis as it relates to age?

Answer 30

The younger the patient the higher the risk of post-splenectomy sepsis In children: 1 in 175 patient-yeears In adults: 1 in 400-500 patient-years

Question 31

What is the most common organizms that cause postsplenectomy sepsis?

Answer 31

Encapsulated bacteria, including... 1) Streptococcus pneumoniae 2) Haemophilus influenzae 3) Neisseria menigitidis [MUST KNOW THESE 3]

Question 32

Patient with history of recent splenectomy with vague abdominal pain, anorexia, leukocytosis and thrombcytosis, what diagnosis must you be suspicious for? What is your next step to evaluate? What is the treatment?

Answer 32

portal vein thrombosis Next step = CT Abdomen/Pelvis w/ IV contrast Treatment: anticoagulation

Question 33

In a patient with newly diagnosed idiopathic thrombocytopenic purpura (ITP), what are the advantages and disadvantages of splenectomy versus thrombopoietin receptor agonists?

Answer 33

Splenectomy: * Pro: gold standard; Most effective response! (overal 88%, partial 22%, complete 66%) * Con: risk of surgery, risk of overwhelming postplenectomy infection, INCREASED risk of thrombotif events Thrombopoietin receptor agonist (TPO-RAs; i.e. fostamatinib) * Pro: nonsurgical, 80% response rate. PO agents administered once a week and at home * Con: Long term treatment; uknown long-term risks; potential for toxicity

Question 34

Describe the typical apperance of splenic abscess vs. cyst vs. neoplasm on CT

Answer 34

Abscess: hypodense lesion; +/- heterogeneous; +/-peripheral enhancement with septations if present for long periods of time Cyst: simple low density lesions w/o peripheral enhancement. Well demarcated. Neoplasm: irregular margins, +heterogenous, density of soft tissue; +/- enhancement w/ contrast, central necrosis, vascularity or invasion into other structures

Question 35

Describe epidemiology of the two most comon hydatid diseases: Echinococcus granulosus Echinococcus multilocularis

Answer 35

**Echinococcus granulosus:** more commonly associated with hydatid cysts. Found in dogs, sheep, cattle and pigs. Found in Europe, Africal, Middle East, Central and South America. Rarely occurs in the North America **Echinococcus multilocularis** less commonly involves humans, but cause more severe disease compared to E. granulosus Found in small rodents, dogs and foxes Cound in northern areas of North America, Europe and Asia

Question 36

What is the patient presentation of a patient with possible splenic abscess?

Answer 36

LUQ pain + tenderness Splenomegaly Fever Left sided pleural effusion or pleuretic chest pain History of trauma, recent abd surgery or other infection (endocarditis, appendicitis, diverticulitis)

Question 37

What is your differential for a solid splenic lesion?

Answer 37

- Splenic metastases (commonly from breast, lung and melanoma) - Primary splenic neoplasm (rare; i.e. angiosarcomas, lymphangiomas, lymphangiosarcomas) - Lymphoproliferative lesion (non-hogdjkin and hodgjkin lymphoma, hairy cell leukemia, chronic lymphocytic leukemia) - Myeloproliferative lesion (chronic myeloid leukemia)

Question 38

Splenic abscess: - mortality rate? - monomicrobial or polymicrobial? - Treatment?

Answer 38

Mortality: 47% Polymicrobial infection Tx: - broad-specturm antibiotic (piperacillin-tazobactam), - if immunocompromised cover for Candida, Aspergillus, and Mycobacterium - Splenectomy [MAINSTAY of treatment] - if multiple comorbidities prevent splenectomy --\> can attempt CT-guided aspiration + IV broad Abx

Question 39

For a simple splenic cyst, what are some potential surgical interventions?

Answer 39

1) Deroofing: remove the whole extrasplenic wall of the cyst 2) Fenestration: excising the cyst wall to within 1 centimeter of the splenic rim 3) Partial splenectomy

Question 40

What are some key principles of operative management of splenic hydatid cysts in comparision to splenectomy for other cysts?

Answer 40

- MUST NOT rupture the cyst! 1) Can cause anaphylaxis --\> anesthesia team must have epinephrine on hand 2) Spillage of contents can lead to further intra-abdominal spread of the disease - For Ecchinococcus Multilocularis, recommend oncologic principles be followed. Free margin of at least 1 cm due to invasive nature of infection

Question 41

What is the management for immune thrombocytopenic purpura (ITP)?

Answer 41

Depends on severity of THROMBOCYTOPENIA!! - **Asymptomatic + Plt \> 50K** = observation - **Symtomatic with plt \< 50k** = glucocorticoid (prednisone) is initial therapy [66% improvement in plts in 1 to 3 weeks; 25% with complete reponse] ---\> If refractory to steroids then Rituximab - **Any severe hemorrhage** = Platelet transfusion + IVIG (also give IVIG if prepping for splenectomy) - **Splenectomy** = [failed medical therapy} OR [pregnant + failed medical therapy + p t\< 10k w/lo sx or plt \<30k w/ bleeding]