Blood & Lymphoreticular

Splenectomy: indications and post-splenectomy prophylaxis

Clinical Overview and When to Suspect Splenectomy Need

— Anatomic: surgical removal, congenital absence

— Functional: sickle cell disease (autosplenectomy by age 5), celiac disease, IBD, advanced cirrhosis, post-radiation, HIV, amyloidosis

— Trauma: hemodynamically unstable blunt abdominal trauma with splenic injury failing nonoperative management; grade IV–V lacerations with active extravasation

— Hematologic: hereditary spherocytosis (moderate–severe), refractory ITP after failed steroids/IVIG/rituximab/TPO mimetics, autoimmune hemolytic anemia refractory to medical therapy, hairy cell leukemia (rarely now), splenic marginal zone lymphoma

— Hypersplenism: symptomatic cytopenias from portal hypertension, Gaucher disease, thalassemia major

— Other: splenic abscess refractory to drainage, splenic vein thrombosis with bleeding gastric varices, large symptomatic splenic cysts/tumors

— Sickle cell patient with Howell-Jolly bodies on smear → assume asplenic regardless of imaging

— Long-standing celiac disease with recurrent encapsulated infections

— Cirrhotic with marked thrombocytopenia and splenomegaly

Board pearl: The presence of Howell-Jolly bodies, target cells, acanthocytes, and thrombocytosis on a peripheral smear is pathognomonic of asplenia/hyposplenism — recognize this combination instantly. Step 3 management: Any patient identified as functionally asplenic deserves the same vaccination and counseling bundle as a post-surgical splenectomy patient, even if no surgery is ever planned.

Splenectomy = surgical removal of the spleen, performed for trauma, hematologic disease, hypersplenism, malignancy, or diagnostic indication. The spleen is critical for opsonization and clearance of encapsulated organisms, filtering senescent RBCs, and housing memory B cells producing anti-polysaccharide IgM.

Anatomic vs functional asplenia — both confer identical infection risk and identical prophylaxis obligations.

Major indications encountered on Step 3:

When to suspect a patient is functionally asplenic on the wards/clinic:

Presentation Patterns and Key History

— Pre-op planning: stable patient with elective indication (HS, ITP, splenic mass) — your job is to ensure vaccinations are completed ≥14 days before surgery and informed consent addresses lifelong infection risk

— Post-op outpatient: weeks-to-years post-splenectomy presenting for routine care, immunization updates, or with a febrile illness

— Emergent: post-splenectomy patient presenting febrile/septic → presumed OPSI (overwhelming post-splenectomy infection) until proven otherwise

— Date and indication of splenectomy — risk of OPSI is highest in first 2 years but lifelong

— Vaccination history: pneumococcal (PCV20 or PCV15+PPSV23), meningococcal ACWY and B, Hib, annual influenza, COVID-19

— Antibiotic prophylaxis status: daily penicillin V or amoxicillin, especially in children <5 yr post-splenectomy and adults in first 1–2 years; some recommend lifelong in high-risk

— Standby antibiotic prescription ("pill in pocket") — amoxicillin-clavulanate or levofloxacin to take immediately if fever ≥38.0°C while seeking care

— Travel history: babesiosis (Northeast US), malaria — both are far more severe in asplenic patients

— Animal bites: Capnocytophaga canimorsus from dog bites causes fulminant sepsis in asplenics

— Tick exposure: babesiosis and ehrlichiosis run a fulminant course

Key distinction: Splenectomy patients are not just "immunocompromised" generally — they are uniquely vulnerable to encapsulated bacteria (S. pneumoniae, N. meningitidis, H. influenzae) and intraerythrocytic parasites (Babesia, Plasmodium), not to viral or fungal pathogens preferentially. Board pearl: Always ask asplenic patients about dog/cat exposures and tick bites — these change empiric antibiotic choice.

Three Step 3 archetypes for splenectomy-relevant patients:

History elements that change management:

Red-flag chief complaints: fever, rigors, malaise, vomiting, confusion in any asplenic patient = emergency triage.

Physical Exam Findings (and Hemodynamic Assessment when relevant)

— Splenomegaly: palpate from RLQ moving toward LUQ on inspiration; massive spleens (>20 cm) common in myelofibrosis, CML, Gaucher, marginal zone lymphoma

— Stigmata of underlying disease: jaundice/scleral icterus (HS, AIHA), petechiae and wet purpura (ITP), pallor, lymphadenopathy

— Left subcostal or midline laparotomy scar; laparoscopic port sites

— Compensatory thrombocytosis can cause subtle peripheral findings; check for DVT signs

— Vitals first: qSOFA (RR ≥22, altered mentation, SBP ≤100), temperature, capillary refill

— Skin: purpura fulminans — symmetric peripheral purpura with necrosis, especially digits, nose, ears → DIC from pneumococcal or meningococcal sepsis

— Neuro: meningismus, Kernig/Brudzinski (meningococcus, pneumococcus)

— Mucous membranes for petechiae

— Abdominal exam for tenderness suggesting alternative source

— Treat as septic shock until disproven

— Two large-bore IVs, fluid bolus 30 mL/kg crystalloid, lactate, blood cultures × 2, then antibiotics within 1 hour — do NOT wait for cultures

— Norepinephrine first-line vasopressor if MAP <65 after fluids

CCS pearl: In simulated CCS cases, the order set for febrile asplenic is: CBC with diff and smear, BMP, lactate, blood cultures × 2, UA/urine cx, CXR, LP if no contraindication, ceftriaxone 2 g IV plus vancomycin STAT, then ICU consult. Do not delay antibiotics for LP if patient is unstable. Board pearl: Mortality of OPSI exceeds 50% when treatment is delayed >6 hours — sepsis can progress from well-appearing to death in under 24 hours.

Pre-operative exam (elective splenectomy candidates):

Post-splenectomy stable exam:

Acute febrile post-splenectomy patient — OPSI assessment:

Hemodynamic approach in suspected OPSI:

Diagnostic Workup — Initial Labs / Imaging / ECG / Biomarkers

— Howell-Jolly bodies (nuclear DNA remnants) — sensitive marker of hyposplenism

— Target cells, acanthocytes, Pappenheimer bodies, Heinz bodies, nucleated RBCs, lymphocytosis

— Reactive thrombocytosis (often 500,000–1,000,000) in first weeks post-op, usually normalizes

— Hereditary spherocytosis: anemia, ↑MCHC, ↑reticulocytes, indirect hyperbilirubinemia

— ITP: isolated thrombocytopenia <100k, normal smear otherwise

— AIHA: anemia, spherocytes, positive direct Coombs (DAT), ↑LDH, ↓haptoglobin

— Hypersplenism: pancytopenia with preserved marrow

— Type and crossmatch, coagulation panel, comprehensive metabolic panel

— Vaccine titers not routinely required — vaccinate per schedule regardless

— Pregnancy test in reproductive-age females

— FAST exam for free fluid in unstable blunt abdominal trauma

— CT abdomen/pelvis with IV contrast in stable patients → AAST splenic injury grading (I–V)

— Active contrast extravasation on CT = high failure rate of nonoperative management

— Blood cultures × 2 from separate sites

— CBC, CMP, lactate, coags/fibrinogen/D-dimer (DIC panel), procalcitonin

— UA, CXR, LP if meningitis suspected and no contraindication

— Buffy coat Gram stain can show pneumococci directly in OPSI — classic finding

Step 3 management: When ordering pre-splenectomy labs in a CCS case, also order vaccination administration in the same visit if not yet completed — don't separate these orders. Board pearl: The Howell-Jolly body on a smear in a sickle cell patient is your trigger to verify lifelong asplenia prophylaxis is in place — many patients fall through the cracks.

Peripheral smear is the single highest-yield test to confirm functional asplenia:

CBC patterns by indication:

Pre-operative workup:

Trauma workup:

OPSI workup (concurrent with antibiotics — never delay treatment):

Diagnostic Workup — Advanced or Confirmatory Studies

— Eosin-5-maleimide (EMA) binding flow cytometry — preferred over osmotic fragility test

— Acidified glycerol lysis test as alternative

— Genetic testing (ankyrin, spectrin, band 3) for ambiguous cases

— Ultrasound: first-line for splenic size, cysts, abscess in stable patients

— CT with contrast: trauma grading, masses, vascular anatomy, accessory spleens

— MRI: characterize indeterminate lesions; iron quantification in thalassemia

— Tagged RBC scan: confirms accessory spleen as cause of relapsed ITP post-splenectomy

— Howell-Jolly body quantification by flow (>4% pitted RBCs)

— Spleen imaging (US or technetium-99m sulfur colloid scan showing absent uptake)

Key distinction: Splenectomy is curative in hereditary spherocytosis (>90% response) but only achieves durable remission in ~60–70% of ITP — set patient expectations accordingly. Board pearl: Post-splenectomy relapse of ITP after initial response → think missed accessory spleen — order a heat-damaged RBC or Tc-99m scan.

Hereditary spherocytosis confirmation:

ITP: clinical diagnosis of exclusion; bone marrow biopsy only if atypical features (age >60, abnormal smear, splenomegaly) — Step 3 expectation is that splenectomy is second/third-line after failure of corticosteroids, IVIG, rituximab, and TPO receptor agonists (eltrombopag, romiplostim)

AIHA: DAT pattern distinguishes warm (IgG, often idiopathic or lymphoma/SLE) vs cold (C3, mycoplasma, EBV, lymphoma); splenectomy effective for warm AIHA only

Imaging modalities for spleen:

Confirming functional asplenia when surgical history unclear:

Accessory spleens: present in ~15–30% of patients; should be sought and removed during elective splenectomy for ITP/AIHA to prevent relapse. Imaging or intraoperative inspection.

Pre-op imaging for massive splenomegaly: CT angiography to map splenic vessels — consider preoperative splenic artery embolization to reduce intraoperative blood loss.

Risk Stratification or First-Line Management Logic

— Hemodynamically unstable + positive FAST → emergency laparotomy with splenectomy

— Stable + grade I–III injury, no extravasation → nonoperative management with ICU monitoring, serial Hb, bed rest

— Stable + grade IV–V or contrast blush → splenic artery embolization preferred over surgery when available; spleen-preserving

— Failure of nonoperative management (ongoing transfusion need, hemodynamic decline) → splenectomy

— First-line: corticosteroids (prednisone or high-dose dexamethasone) ± IVIG for bleeding

— Second-line: rituximab, TPO receptor agonists (eltrombopag, romiplostim, avatrombopag), fostamatinib

— Splenectomy reserved for chronic refractory ITP, ideally after 12 months of disease (allows spontaneous remission) and after failure of medical therapy

— Mild: observe, folate supplementation

— Moderate–severe: splenectomy improves anemia, reduces gallstones; partial splenectomy considered in children <6 years to preserve immune function

— Delay until age ≥6 years when possible

— Elective: vaccinate ≥14 days before splenectomy for maximal antibody response

— Emergency/trauma: vaccinate ≥14 days after surgery (immune response is suboptimal during acute illness)

Step 3 management: When a question asks about timing of pneumococcal vaccination relative to elective splenectomy, the answer is at least 2 weeks before surgery. If emergent, give 2 weeks after. Board pearl: Splenic artery embolization has replaced splenectomy as the preferred intervention for hemodynamically stable high-grade splenic trauma with contrast extravasation — recognize this trend on exams.

Trauma decision tree (Step 3 favorite):

Pediatric trauma: nonoperative management strongly preferred — preserve spleen whenever possible due to lifelong OPSI risk

ITP stepwise management before splenectomy is considered:

Hereditary spherocytosis stratification:

Vaccination timing logic (universal):

Pharmacotherapy — First-Line Drug Regimen (Prophylaxis)

— Children: penicillin V 125 mg PO BID (<5 yr) or 250 mg PO BID (≥5 yr) — continue until at least age 5 and at least 1–2 years post-splenectomy; many experts continue through adolescence

— Adults: penicillin V 250–500 mg PO BID OR amoxicillin 500 mg daily for at least 1–2 years post-splenectomy, indefinitely in high-risk (prior OPSI, hematologic malignancy, immunosuppression, age <16 or >50)

— Penicillin-allergic: macrolide (azithromycin) or TMP-SMX; fluoroquinolone in adults

— Amoxicillin-clavulanate 875/125 mg PO — take first dose immediately at onset of fever ≥38°C or rigors, then proceed to ED

— Alternatives in penicillin allergy: levofloxacin or moxifloxacin

— Patient must understand this is a bridge, NOT a substitute for ED evaluation

— Ceftriaxone 2 g IV q12h PLUS vancomycin (for ceftriaxone-resistant pneumococcus)

— Add doxycycline if babesiosis/ehrlichiosis suspected (tick exposure)

— Add clindamycin + atovaquone or azithromycin + atovaquone for babesiosis

— Meningitis: add dexamethasone before/with first antibiotic dose if pneumococcal suspected

CCS pearl: On a CCS clinic visit for a stable post-splenectomy patient, your orders should include: verify vaccinations, prescribe daily penicillin V, prescribe standby amoxicillin-clavulanate, provide MedicAlert bracelet counseling, and document patient education on fever response. Board pearl: Daily prophylaxis does NOT eliminate OPSI risk because of resistant pneumococci — vaccination remains essential.

Daily antibiotic prophylaxis — the cornerstone of post-splenectomy outpatient management:

Standby ("emergency") antibiotic — every asplenic adult should have a prescription at home:

Empiric therapy for confirmed/suspected OPSI in hospital:

Antimalarial chemoprophylaxis before travel to endemic regions — asplenics develop fulminant malaria.

Vaccinations — The Five-Vaccine Bundle (Critical Step 3 Material)

— Current ACIP-preferred: PCV20 alone, OR PCV15 followed by PPSV23 ≥8 weeks later

— If previously received PCV13: give PPSV23 ≥8 weeks later, then second PPSV23 dose 5 years later

— Asplenia is a high-risk indication — vaccinate even patients <65 who would not otherwise qualify

— MenACWY (Menactra/Menveo/MenQuadfi): 2-dose primary series 8 weeks apart, then booster every 5 years for life

— MenB (Bexsero 2-dose or Trumenba 3-dose series), then booster 1 year after primary, then every 2–3 years if ongoing risk

— Single dose if not previously vaccinated as a child; one-time for all asplenic adults

— Elective splenectomy: complete vaccines ≥14 days before surgery

— Emergency splenectomy: vaccinate ≥14 days after surgery (consensus; some give at 2 weeks, others wait until discharge; the principle is to allow immune recovery)

— Live vaccines (MMR, varicella, zoster RZV is non-live and OK) can be given to asplenics — asplenia alone is NOT a contraindication to live vaccines

Step 3 management: When you see a vignette of a stable post-splenectomy patient at any clinic visit, default actions are: review vaccine record, update due vaccines, verify daily and standby antibiotics, counsel on fever. Missing any of these is the wrong answer. Board pearl: MenACWY boosters every 5 years for life in asplenics — this is unique to the high-risk population and frequently tested.

Pneumococcal (highest yield):

Meningococcal — TWO products required:

Haemophilus influenzae type b (Hib):

Influenza: annual inactivated vaccine — live attenuated (LAIV) contraindicated only if also immunocompromised; otherwise reduces bacterial superinfection

COVID-19: per current CDC schedule, including boosters

Timing rules (memorize):

Documentation: maintain a written asplenia vaccination card and immunization registry entry; flag chart prominently.

Special Populations — Elderly and Renal/Hepatic Impairment

— Higher perioperative mortality from splenectomy — consider less-invasive alternatives (rituximab, TPO agonists for ITP; observation for asymptomatic conditions)

— OPSI risk is higher in adults >50 with poorer outcomes

— Pneumococcal vaccination already indicated at 65, but ensure both PCV20 (or PCV15+PPSV23) and meningococcal coverage are in place

— Polypharmacy review for interactions with prophylactic antibiotics (e.g., warfarin + TMP-SMX → INR rise)

— Consider lifelong daily antibiotic prophylaxis given higher OPSI mortality

— Adjust penicillin V dosing minimally; amoxicillin needs adjustment if CrCl <30

— Levofloxacin standby antibiotic requires renal dose adjustment

— Vaccinations unchanged — give per asplenia schedule regardless of renal function

— Avoid nephrotoxic combinations during sepsis management (vanc + piperacillin-tazobactam → AKI risk)

— Cirrhotics with hypersplenism: splenectomy is rarely indicated; TIPS or treatment of portal hypertension preferred

— Cirrhotics have functional asplenia even with spleen present → still require full vaccination bundle

— Avoid drugs with significant hepatic metabolism issues; amoxicillin-clavulanate carries cholestatic injury risk in cirrhotics

— Increased OPSI risk due to combined splenic and complement deficits

— Vaccinate when CD4 >200 or between chemo cycles when possible

— May require booster doses more frequently; check antibody titers

Board pearl: Cirrhotic patients are functionally asplenic even without splenectomy and deserve the full asplenia vaccination bundle — a commonly missed point. Step 3 management: In the elderly post-splenectomy patient, lower your threshold for indefinite daily antibiotic prophylaxis and ensure annual influenza plus updated pneumococcal status at every encounter.

Elderly patients (>65):

Renal impairment:

Hepatic impairment / cirrhosis:

Immunocompromised overlap (HIV, chemotherapy, post-transplant):

Special Populations — Pregnancy and Pediatrics

— OPSI risk is unchanged but consequences for mother and fetus are severe

— All asplenia vaccines are safe in pregnancy (inactivated): pneumococcal, meningococcal, Hib, influenza, Tdap, COVID-19

— Live vaccines (MMR, varicella) deferred to postpartum

— Continue daily antibiotic prophylaxis: penicillin V and amoxicillin are pregnancy category B — safe

— Avoid TMP-SMX in first trimester (folate antagonism, neural tube defects) and near term (kernicterus risk)

— Avoid fluoroquinolones (cartilage concerns) and doxycycline (fetal teeth/bone)

— Standby antibiotic in pregnancy: amoxicillin-clavulanate is preferred

— Counsel on increased thromboembolism risk — pregnancy + post-splenectomy thrombocytosis compounds VTE risk

— Delay elective splenectomy until ≥6 years when feasible (e.g., hereditary spherocytosis) to reduce OPSI risk

— Partial splenectomy or splenic embolization considered in young children

— Routine childhood immunizations PLUS asplenia-specific schedule:

· PCV15/PCV20 series per age

· PPSV23 at ≥2 years of age, 8 weeks after PCV

· MenACWY starting at 2 months (high-risk schedule), MenB at age ≥10

· Hib if not completed in infancy

— Daily penicillin V prophylaxis through age 5 at minimum; many experts continue through adolescence

— Sickle cell children: same regimen — penicillin V from infancy

Board pearl: Asplenic pregnant patients should receive inactivated influenza vaccine in every pregnancy regardless of season timing, plus standard asplenia bundle catch-up. Key distinction: Partial splenectomy in young children with HS preserves immune function while controlling hemolysis — a niche but testable concept.

Pregnancy in the asplenic patient:

Pediatric splenectomy:

Sickle cell disease specifically: functional asplenia by age 5 → start penicillin V at 2 months of age, continue at least through age 5 per CDC.

Complications and Adverse Outcomes

— Hemorrhage (especially in portal hypertension)

— Subphrenic abscess — left upper quadrant pain, fever, elevated diaphragm on CXR; CT confirms

— Pancreatic tail injury → pancreatic fistula, pseudocyst (spleen and pancreatic tail share blood supply)

— Atelectasis, left pleural effusion, pneumonia

— Gastric perforation from short gastric vessel injury

— Ileus

— Reactive thrombocytosis peaks 1–2 weeks postop, often >1,000,000/µL

— Portal/splenic/mesenteric vein thrombosis — abdominal pain, ascites, transaminitis; especially common in myeloproliferative disorders

— VTE prophylaxis is essential; consider aspirin if platelets persistently elevated

— Long-term increased cardiovascular and pulmonary embolism risk

— Lifetime risk ~5%; mortality 50–70% if presentation delayed

— Highest risk first 2 years post-splenectomy but persists for life

— Pathogens: S. pneumoniae (>50%), N. meningitidis, H. influenzae, Capnocytophaga, Babesia, Plasmodium

— Presents with nonspecific prodrome (malaise, fever, GI symptoms) → fulminant sepsis with Waterhouse-Friderichsen syndrome (adrenal hemorrhage) and purpura fulminans within hours

— DIC, multiorgan failure, death

— Increased risk of pulmonary hypertension (especially after splenectomy for hemolytic anemias)

— Increased solid tumor and hematologic malignancy risk (modest)

— Atherosclerotic cardiovascular disease — modestly increased

Board pearl: Post-splenectomy fever within first 2 years carries the highest OPSI risk, but the lifetime risk never returns to zero — counsel patients to treat every fever as an emergency forever. Step 3 management: Post-splenectomy patient with platelets >1,000,000 and abdominal pain → image for portal vein thrombosis with Doppler ultrasound or CT venography.

Early postoperative complications:

Thrombotic complications:

Infectious complications — OPSI (Overwhelming Post-Splenectomy Infection):

Long-term sequelae:

When to Escalate Care — ICU, Consult, or Inpatient Triage

— Hypotension unresponsive to initial fluid resuscitation

— Altered mental status or meningeal signs

— Respiratory failure, ARDS pattern

— DIC (thrombocytopenia, prolonged PT/PTT, fibrinogen <150, elevated D-dimer)

— Lactate >4 mmol/L

— Purpura fulminans or evidence of Waterhouse-Friderichsen

— ANY fever ≥38°C in an asplenic patient warrants ED evaluation; admission for IV antibiotics if any signs of systemic illness, abnormal vitals, abnormal labs, or unreliable follow-up

— Even well-appearing asplenic patients with fever often warrant admission for 24–48 hours of IV antibiotics

— Hematology: for management of underlying disorder (ITP, AIHA, hemolytic anemias), perioperative planning

— Surgery: trauma, elective splenectomy planning, postoperative complications

— Infectious disease: OPSI, atypical infections (Babesia, Capnocytophaga), persistent fever despite empiric therapy, vaccine response questions

— Interventional radiology: splenic artery embolization for trauma or pre-op

— Critical care: septic shock, DIC

— Trauma center for grade IV–V splenic injuries

— Tertiary center if no IR available for embolization candidates

CCS pearl: In a CCS case with a febrile asplenic adult, the correct sequence is: ED triage → vital signs and labs → blood cultures × 2 → ceftriaxone + vancomycin within 1 hour → fluid resuscitation → ICU admission if any organ dysfunction. Do not "send home with oral antibiotics" — that is a wrong answer almost universally on Step 3. Board pearl: A well-appearing asplenic patient with a fever still warrants at minimum a several-hour ED observation with IV antibiotics — outpatient management is rarely appropriate.

Immediate ICU admission criteria for suspected OPSI:

Inpatient admission threshold (lower than general population):

Consultation triggers:

Transfer considerations:

Key Differentials — Same-Category Causes (Infection in the Asplenic Patient)

— Streptococcus pneumoniae — >50% of OPSI cases; presents as pneumonia, meningitis, or primary bacteremia; risk of DIC and purpura fulminans

— Neisseria meningitidis — meningococcemia with petechial/purpuric rash, Waterhouse-Friderichsen syndrome

— Haemophilus influenzae type b — much rarer in vaccinated era; bacteremia, meningitis, epiglottitis

— Capnocytophaga canimorsus — gram-negative rod from dog (and less often cat) bites; fulminant sepsis with DIC, purpura fulminans; treat with amoxicillin-clavulanate or third-generation cephalosporin; doxycycline if penicillin-allergic

— Salmonella spp. — increased bacteremia risk

— Bordetella holmesii — rare but severe in asplenia

— Babesiosis — Babesia microti (Northeast/Upper Midwest US); high parasitemia, hemolysis, multiorgan failure; treat with atovaquone + azithromycin (mild) or clindamycin + quinine (severe); consider exchange transfusion if parasitemia >10%

— Malaria — fulminant P. falciparum; prophylaxis essential for travel

— Ehrlichia/Anaplasma — treat with doxycycline (give even before confirmation if suspected)

— Dog bite → think Capnocytophaga

— Tick exposure or Northeast US travel → think Babesia/Ehrlichia

— Petechial rash + meningismus → Neisseria

— Lobar consolidation + sepsis → Pneumococcus

Board pearl: Buffy coat smear showing gram-positive diplococci in a febrile asplenic patient → pneumococcal sepsis with massive bacteremia — a near-pathognomonic exam image. Key distinction: Babesiosis in an asplenic patient can present with parasitemia >20% and requires exchange transfusion — far more severe than in immunocompetent hosts.

Bacterial encapsulated organisms (the classic triad):

Other bacteria with disproportionate severity in asplenia:

Intraerythrocytic parasites:

Tick-borne co-infections in endemic areas:

Distinguishing features on history:

Key Differentials — Other-Category Causes

— Infectious: EBV, CMV, malaria, visceral leishmaniasis, schistosomiasis, endocarditis

— Hematologic malignancy: CLL, CML, myelofibrosis, hairy cell leukemia, splenic marginal zone lymphoma

— Storage disease: Gaucher (glucocerebrosidase deficiency), Niemann-Pick

— Portal hypertension: cirrhosis, splenic vein thrombosis, Budd-Chiari

— Hemolytic anemias: HS, thalassemia, sickle cell variants, AIHA

— Inflammatory: SLE, sarcoidosis, Felty syndrome (RA + neutropenia + splenomegaly)

— Treat the cause, not the spleen, when possible: TIPS for portal hypertension, enzyme replacement for Gaucher (imiglucerase), chemo for hematologic malignancies

— Meningococcemia → Waterhouse-Friderichsen

— Pneumococcal DIC → purpura fulminans

— Capnocytophaga sepsis

— TTP/HUS (consider if MAHA + thrombocytopenia + renal injury + neuro symptoms)

— DIC from any source

— Always treat as OPSI first; rule out viral URI/influenza only after empiric coverage

— Babesiosis in summer/early fall in endemic areas

— Post-op subphrenic abscess if recent splenectomy

— Megaloblastic anemia (Howell-Jolly bodies can appear from impaired nuclear extrusion)

— Severe iron deficiency

Step 3 management: A febrile cirrhotic with splenomegaly is still functionally asplenic — empiric antibiotics for sepsis should cover encapsulated organisms even though the spleen is anatomically present. Board pearl: Felty syndrome (RA + splenomegaly + neutropenia) can be an indication for splenectomy if recurrent infections occur despite optimal RA management, though rituximab is often tried first.

Splenomegaly differential (when deciding whether splenectomy is needed):

Hypersplenism differential (cytopenias + splenomegaly):

Differentials for purpura/petechiae in an asplenic patient (urgent):

Differentials for non-specific febrile illness in asplenic patient:

Mimics of asplenia on smear:

Secondary Prevention / Discharge Medications / Long-Term Plan

— Vaccinations: documented pneumococcal (PCV20 or PCV15+PPSV23), MenACWY + MenB, Hib, influenza, COVID-19 — given 2 weeks before elective or 2 weeks after emergent splenectomy

— Daily antibiotic prophylaxis: penicillin V 250–500 mg BID or amoxicillin 500 mg daily — minimum 1–2 years, lifelong in high-risk

— Standby antibiotic: prescription for amoxicillin-clavulanate 875/125 mg in patient's possession

— Patient education: written and verbal fever-action plan

— MedicAlert bracelet or similar asplenia identification

— Vaccination wallet card kept by patient

— Annual influenza vaccine

— MenACWY booster every 5 years for life

— PPSV23 booster 5 years after first dose (if using PCV15+PPSV23 strategy); not needed with PCV20-only

— MenB booster every 2–3 years if ongoing risk

— Pneumococcal antibody titers not routinely measured but can guide repeat dosing in some specialty centers

— Pre-travel consultation 4–6 weeks before international trips

— Malaria chemoprophylaxis to endemic areas

— Avoid tick-endemic areas during peak season or use DEET/permethrin rigorously

— Yellow fever vaccine (live) is acceptable in pure asplenia

— Pre-travel typhoid, hepatitis A/B as indicated

— Avoid contact with sick individuals during outbreaks

— Prompt care for dog/cat bites — start prophylactic amox-clav

Step 3 management: At every visit for any post-splenectomy patient — annual physical, urgent care, ED — verify vaccine status and prophylactic antibiotic adherence. These are recurrent missed opportunities. Board pearl: MedicAlert bracelet counseling is a frequently tested Step 3 expectation for asplenia management.

Discharge checklist after splenectomy (memorize for CCS):

Long-term surveillance:

Travel medicine:

Lifestyle counseling:

Follow-Up, Monitoring Parameters, and Rehab/Counseling

— 2 weeks: wound check, review pathology if applicable, assess for thrombocytosis, confirm vaccination plan

— 4–6 weeks: CBC to monitor platelet trend, confirm prophylactic antibiotic adherence

— 3 months: completion of meningococcal series if needed, reinforce education

— Annual lifelong follow-up: vaccine boosters, fever-action plan review, screening for underlying disease recurrence (ITP, AIHA)

— Platelet count: typically trends back toward normal over weeks to months; persistent elevation >1,000,000 may warrant aspirin

— Smear for residual hemolysis (in HS, AIHA) — should see resolution

— Hemoglobin and reticulocyte count in hemolytic anemia patients

— Liver function if amox-clav used long-term

— Annual pulmonary symptom screen — pulmonary hypertension surveillance especially after splenectomy for chronic hemolytic disease (thalassemia, HS); echocardiogram if symptoms

— Fever recognition: any temp ≥38°C = take standby antibiotic + go to ED

— Sepsis warning signs: rigors, confusion, vomiting, rash, breathlessness

— Animal bite protocol: clean, seek care, start amox-clav

— Tick bite protocol in endemic areas

— Travel planning months in advance

— Compliance with daily prophylactic antibiotic — explain non-substitutability with vaccines

CCS pearl: A 12-month post-splenectomy CCS clinic visit should always include: CBC, vaccine review and update, antibiotic adherence check, fever-plan review, and chart-flag verification. Board pearl: Recurrence of cytopenias months to years after splenectomy for ITP/AIHA — search for accessory spleen via Tc-99m heat-damaged RBC scan.

Postoperative follow-up schedule:

Monitoring parameters:

Patient counseling components (must be documented):

Documentation in chart: prominent allergy/alert-tab note "ASPLENIA — increased infection risk" so any clinician seeing the patient is aware.

Ethical, Legal, and Patient Safety Considerations

— Must explicitly discuss lifelong infection risk including OPSI mortality (5% lifetime, 50% mortality if delayed treatment)

— Discuss alternatives (medical therapy for ITP/AIHA, partial splenectomy, observation)

— Document patient understanding of lifelong vaccination and antibiotic obligations

— For minors, both parents/guardians' consent ideal; assent from child ≥age 7

— Jehovah's Witness patients with hemolytic anemias requiring splenectomy: pre-op iron, erythropoietin, careful surgical planning; cell salvage techniques where acceptable; advance directive documentation

— Emergent splenectomy patients are at highest risk of falling through cracks — they may never receive proper vaccinations because the discharge is rushed

— Recommendations: standardized discharge checklist, pharmacy-driven vaccine protocols, primary care handoff with explicit asplenia documentation

— EMR alerts/banners for asplenia status are evidence-based and reduce missed prophylaxis

— Medication reconciliation must verify daily and standby antibiotics at every transition

— Invasive meningococcal disease and certain pneumococcal serotypes are reportable to public health departments

— Close contacts of meningococcal cases require prophylaxis (ciprofloxacin, rifampin, or ceftriaxone single dose)

— MedicAlert bracelet prevents delayed recognition during unconscious presentation

— Asplenia status on every prescription refill request triggers prophylaxis verification

— Counsel against abrupt cessation of daily antibiotics without explicit discussion

Step 3 management: The most common safety failure in asplenic patients is inadequate handoff after emergency splenectomy. A discharge summary that fails to specify vaccination plan and antibiotic prophylaxis is a documented safety event. Board pearl: EMR best-practice alerts for asplenia have demonstrated reductions in missed vaccinations and missed empiric antibiotic dosing in OPSI presentations.

Informed consent for elective splenectomy:

Religious objections to blood products:

Transition-of-care risks (a major Step 3 patient safety domain):

Mandatory reporting and public health:

Patient safety pearls:

Vaccine refusal: document discussion, address misconceptions, revisit at subsequent visits; cannot be coerced but must be documented thoroughly.

High-Yield Associations and Rapid-Fire Clinical Facts

— Howell-Jolly bodies (DNA remnants)

— Pappenheimer bodies (iron granules)

— Heinz bodies (denatured hemoglobin)

— Target cells, acanthocytes, spherocytes

— Nucleated RBCs, thrombocytosis, lymphocytosis

— Strep pneumoniae, Neisseria meningitidis, Klebsiella pneumoniae, H. influenzae type b, Pseudomonas, Bordetella, Cryptococcus, Salmonella, Group B Strep

— Lifetime risk ~5%, mortality 50–70% if delayed treatment

— Highest risk first 2 years post-splenectomy

— Most common organism: Strep pneumoniae

— Most lethal feature: rapid progression — well to dead in <24 hours

— Elective splenectomy: vaccinate ≥2 weeks before

— Emergency splenectomy: vaccinate ≥2 weeks after

Board pearl: The single highest-yield smear finding triggering "verify asplenia" thinking is Howell-Jolly bodies — recognize it instantly. Key distinction: Asplenia confers bacterial and parasitic vulnerability disproportionately, not viral or fungal — this distinguishes asplenia from broad immunosuppression on exams.

Smear findings of asplenia (memorize as a cluster):

Encapsulated organisms — "Some Nasty Killers Have Pretty Big Capsules":

OPSI rapid facts:

Vaccine timing:

Splenic artery embolization has supplanted splenectomy for stable Grade IV–V splenic trauma with contrast extravasation.

Accessory spleens present in 15–30% of patients; account for ITP/AIHA recurrence after splenectomy → detect with Tc-99m heat-damaged RBC scan.

Felty syndrome triad: rheumatoid arthritis + splenomegaly + neutropenia.

Sickle cell autosplenectomy is functionally complete by age 5.

Cirrhosis causes functional asplenia — vaccinate fully.

Capnocytophaga canimorsus from dog bites → fulminant sepsis with DIC.

Babesiosis in asplenics → parasitemia often >10%, requires exchange transfusion.

MenACWY booster every 5 years for life in asplenia.

Daily penicillin V prophylaxis: standard in children, minimum 1–2 years in adults, lifelong in high-risk.

Standby antibiotic: amoxicillin-clavulanate carried by patient at all times.

Board Question Stem Patterns

Step 3 management: When in doubt on a question involving an asplenic patient with any fever, the answer is immediate broad-spectrum IV antibiotics in the ED — almost never outpatient management. Board pearl: Step 3 frequently tests booster intervals (MenACWY every 5 years) and timing of vaccination relative to surgery (2 weeks before elective, 2 weeks after emergent).

Stem 1: "A 22-year-old college student had emergency splenectomy 3 years ago for traumatic injury. He presents to the ED with 6 hours of fever to 39.5°C, rigors, and confusion." → Answer involves immediate IV ceftriaxone + vancomycin within 1 hour, blood cultures, ICU admission. Wrong answers: outpatient antibiotics, await culture results.

Stem 2: "A 6-year-old with hereditary spherocytosis is scheduled for elective splenectomy in 4 weeks. Which intervention should be performed now?" → Answer: administer pneumococcal, meningococcal (ACWY and B), Hib vaccines at least 2 weeks before surgery.

Stem 3: "A 45-year-old asplenic patient returns from a camping trip in Massachusetts with fever, hemolytic anemia, and dark urine. Smear shows intraerythrocytic ring forms." → Babesiosis; treat with atovaquone + azithromycin (or clindamycin + quinine if severe); consider exchange transfusion if parasitemia >10%.

Stem 4: "A 30-year-old woman 5 years post-splenectomy for ITP presents with recurrent thrombocytopenia." → Workup includes Tc-99m heat-damaged RBC scan for accessory spleen.

Stem 5: "A 50-year-old with cirrhosis and splenomegaly presents with pneumococcal sepsis." → Recognize functional asplenia; counsel and document full asplenia vaccination bundle for future.

Stem 6: "An asplenic patient was bitten by his neighbor's dog 12 hours ago and now has fever and a purpuric rash." → Capnocytophaga canimorsus sepsis; treat with amoxicillin-clavulanate or third-generation cephalosporin.

Stem 7: "Post-splenectomy day 10, patient develops LUQ pain and fever." → CT for subphrenic abscess; drain + antibiotics.

Stem 8: "Post-splenectomy day 14, platelets are 1,200,000, patient has abdominal pain." → Portal vein thrombosis; Doppler US/CT venography; anticoagulate.

Stem 9: "Best discharge plan for new splenectomy patient?" → Daily penicillin V + standby amoxicillin-clavulanate + complete vaccine bundle + MedicAlert bracelet + fever-action plan.

One-Line Recap

The asplenic patient — anatomic or functional — faces lifelong, rapidly-fatal infection risk from encapsulated bacteria and intraerythrocytic parasites; management is a five-part bundle: complete vaccinations (pneumococcal, MenACWY + MenB, Hib, influenza, COVID), daily antibiotic prophylaxis, standby emergency antibiotic, MedicAlert identification, and a written fever-action plan with empiric IV ceftriaxone + vancomycin for any fever ≥38°C.

Board pearl: Splenectomy is a single surgical event but a lifelong outpatient management problem — the Step 3 exam tests your ability to remember asplenia at every encounter, recognize fever as an emergency, and execute the prevention bundle without omission. Step 3 management: Every clinic visit for an asplenic patient should re-verify vaccinations, prophylactic antibiotic adherence, standby antibiotic possession, and patient understanding of the fever-action plan — these are the four pillars of safe long-term care.

Vaccination timing: ≥2 weeks before elective splenectomy, ≥2 weeks after emergent; lifelong MenACWY boosters every 5 years; annual influenza; PCV20 or PCV15+PPSV23 series.

Daily prophylaxis: penicillin V 250–500 mg BID or amoxicillin 500 mg daily — minimum 1–2 years post-splenectomy, lifelong in high-risk (prior OPSI, age <16 or >50, immunosuppression, hematologic malignancy).

Emergent OPSI response: blood cultures × 2 + ceftriaxone 2 g IV + vancomycin within 1 hour; add doxycycline for tick exposure, atovaquone+azithromycin for babesiosis, amox-clav coverage for Capnocytophaga (dog bite); ICU admission for any organ dysfunction; mortality exceeds 50% if treatment delayed.

High-yield triggers: Howell-Jolly bodies on smear = functional asplenia; recurrent ITP post-splenectomy = look for accessory spleen on Tc-99m scan; cirrhotic patient = functionally asplenic, vaccinate fully; post-splenectomy thrombocytosis + abdominal pain = portal vein thrombosis.