Preventing and treating infections in children with asplenia or hyposplenia

Question 1

When is the highest risk of overwhelming sepsis for asplenic patients?

Answer 1

First 3y post-splenectomy or the first 3y of life if congenital asplenic

Question 2

What is the mortality rat for asplenic patients with sepsis from encapsulated organisms?

Answer 2

50-75%

Question 3

What are the most common organism causing fulminant sepsis in asplenic patients?

Answer 3

Usually bacteria encapsulated by polysaccharide capsule
1. Streptococcus pneumoniae (~50%)
2. Haemophilus influenza type b 
3. Neisseria meningitidis
4. Salmonella species
5. Escherichia coli
Less common:
1. Pseudomonas
2. Klebsiella
3. Streptococci
4. Staphylococci
From cat or dog bites:
1. Capnocytophaga species
Other infections more at risk for:
1. Malaria
2. Babesia (protozoan)

Question 4

What type of vaccine is preferred in asplenic patients?

Answer 4

Conjugate vaccins

Question 5

What is the recommendation for asplenic patients and pneumococcus vaccine?

Answer 5

1. All asplenic patients should receive both conjugared 12-valent and polysaccharide 23-valent pneumococcal vaccine
2. PCV13 (prevnar) FOUR DOSES @ 2m, 4m, 6m, and 12-15mo for primary series
3. Children 12-24mo without previous doses of PCV13 should receive 2 doses at least 8wk apart
4. Children >24mo without previous doses of PCV13 require one dose
5. If children previously received all required doses of PCV7 or PCV10 in the past should be given PCV13 x one dose asap
6. PPV23 give >24mo and at least 8wk after all doses of PCV13 given, then booster dose 5y after 1st dose
7. If asplenic patient has previously received only PPV23 the patient should receive one dose of PCV13 one year after receipt of PPV23 vaccine

Question 6

What are the recommendations regarding meningococcus vaccine and asplenic patients?

Answer 6

1. All asplenic patients should receive the conjugate quadrivalent meningococcal vaccine (MCV4, Menveo or Menactra)
2. Menveo @ 2mo, 4mo, 6mo and 12-15mo for primary series
3. . Children 12-24mo without previous doses of Menveo should receive 2 doses at least 8wk apart
4. Children >24mo without previous doses of Menveo should receive two doses of any of the quadrivalent conjugate meningococcal vaccine 8wk apart
5. Re-vaccinate q5y
6. No role for meningococcal polysaccharide vaccine (Menomune)
7. Give 4CMenB to all asplenic patients incld. infants when available

Question 7

What are the recommendations regarding Haemophilus influenzae type b (Hib) vaccine and asplenic patients?

Answer 7

1. Hib @2mo, 4mo and 6mo, booster @ 18mo
2. Patients >5yo with no Hib or missed >1 dose need 1 dose
3. Consider one additional dose of Hib for all asplenic patients >5yo even if fully immunized previously
4. Children with asplenia who present with a life-threatening Hib infection should receive Hib vaccine, because the infection itself does not confer lifelong protection.

Question 8

What are the recommendations regarding influenza vaccine and asplenic patients?

Answer 8

Yearly seasonal influenza vaccine is recommended, starting at 6mo to lower risk of secondary bacterial infections

Question 9

What other immunizations might be recommended for individuals travelling to less developed area?

Answer 9

All asplenic patients travelling to less developed areas of the world may be at risk of Salmonella infection and should be immunized for S typhi.

Question 10

What is the recommendations regarding household contacts of asplenic patients and immunization?

Answer 10

Household contacts of asplenic patients should receive all age-appropriate vaccines and the yearly influenza vaccine.

Question 11

What is the recommendations regarding timing of immunizations in elective splenomectomy?

Answer 11

1. Administer vaccine at least 2wk prior to surgery

2. Then 2wks postsplenectomy vaccinate

Question 12

What is the recommendation for antibiotic prophylaxis in infants 0-3mo with asplenia or hyposplenia?

Answer 12

Amoxicillin/clavulanate 10mg/kg/dose PO BID or Penicillin 125mg PO BID or Amoxicllin 10mg/kg/dose PO BID if not tolerated

Also concerned re: E coli, Klebsiella

Question 13

What is the recommendation for antibiotic prophylaxis in infants 3mo to 5yo with asplenia or hyposplenia?

Answer 13

Penicillin VK 125mg PO BID or Amoxicillin 10mg/kg/dose PO BID

Question 14

What is the recommendation for antibiotic prophylaxis in children >5yo with asplenia or hyposplenia?

Answer 14

Pencillin VK 250-300mg PO BID or amoxicillin 250mg PO BID

Question 15

What are the CPS recommendations regarding antibiotic prophylaxis?

Answer 15

1. Minimum of 2y post-splenectomy and for all children <5yo

2. Ideally lifelong prophylaxis recommended

Question 16

What are the recommendations regarding malaria prophylaxis with asplenia?

Answer 16

1. Malaria prophylaxis recommended
2. Sleep under insecticide treated bed net or in AC
3. Use mosquito repellent

Question 17

What is the initial treatment recommended for suspected sepsis in a patient with asplenia (aka with a fever)?

Answer 17

1. Immediate blood culture
2. Ceftriaxone 100mg/kg/dose (max 2g/dose) IV x 1 dose
3. Consider addition of Vancomycin 60mg/kg/day IV q6h

Question 18

What are the CPS recommendations?

Answer 18

1. Physicians educate patients and families about the risks associated with asplenia and hyposplenia, preventive measures that can be taken and interventions that are necessary when a child develops a febrile illness. Because parents often encounter a clinician who underestimates the risk of fever in this setting, providing them with a copy of this statement to show emergency department staff may be helpful.
2. Children with asplenia and hyposplenia should receive all routine childhood immunizations, and some routine vaccinations should be administered on an accelerated schedule with extra doses. All children with these conditions, regardless of age, should receive vaccines to protect against S pneumoniae, N meningitidis, Hib and seasonal influenza.
3. Prophylactic antibiotics should be administered until patients are at least 60 months of age, and longer for children who experience an episode of invasive pneumococcal disease. Consideration should be given to lifelong prophylaxis, although adherence issues and the development of resistant bacteria may favour eventual discontinuation.
4. Patients with asplenia or hyposplenia must be considered at high risk of serious bacterial infection (ie, as presenting with a medical emergency). They should wear a Medic Alert bracelet, be promptly assessed whenever fever occurs and started on antimicrobial therapy immediately unless a nonbacterial source is apparent.