What prophylaxis is recommended in splenectomy patients?

Patients with an absent or dysfunctional spleen (AoDS) are at increased risk of infection, especially with capsulated bacteria.

What are the organisms that can cause infection in patients with AoDS?

• Streptococcus pneumoniae (commonest)
• Neisseria meningitidis
• Haemophilus influenzae type B
• Capnocytophaga canimorsus
• Bordetella holmesii
• Babesia microti
• Plasmodium falciparum
• Salmonella (in cases of sickle cell anaemia)
• Anaplasma may present with recurrent/prolonged and severe infection in AoDS

Prevention of infection – vaccines, antibiotic prophylaxis

Antibiotic

• Antibiotic prophylaxis reduces incidents of sepsis (in children) by up to 50% and mortality by up to 90%.
• However, Prophylactic antibiotics are not absolute protection against infection. Vaccines should be given in conjunction.
• Lifelong prophylaxis is recommended.

What is the risk of sepsis?
The risk of death from sepsis is 600 times more than the general population; the estimated lifetime risk of sepsis is 5%. [Lynch 1996]

When is the risk of infection highest?
- children up to 16 years of age,
- adults over 50 years of age and
- for two years post-splenectomy.

Who must be considered for lifelong prophylaxis?
- Those who have had invasive pneumococcal disease,
- those treated for splenic malignancy
- those who have received splenic irradiation or
- Those who have ongoing graft versus host disease.

Who can be considered for discontinuation of prophylaxis?
- Splenectomy following trauma can be considered for stopping prophylaxis if appropriately counselled.
- Children over 5 years of age with sickle cell disease - can be considered for stopping antibiotic if they have received pneumococcal vaccination and does not have a history of severe pneumococcal disease. Patients’ consultants should be consulted/expert opinions taken.

What are the preferred antibiotics?

Phenoxymethylpenicillin PO

• < 1 year: 62.5mg BD
• 1 – 5 years: 125 mg BD
• >5 years: 250mg BD

Amoxicillin PO (additional cover for H influenzae in children)

• 1 mo – 5 years: 125mg twice daily
• 5 – 12 years: 250mg twice daily
• 12 – 18 years: 500mg twice daily

Erythromycin PO

• 1 mo – 2 years: 125mg twice daily
• 2 – 8 years: 250mg twice daily
• > 8 years: 500mg twice daily

Other antibiotics that have been used – Azithromycin, cefalexin

An emergency rescue pack of antibiotics can be used if regular prophylaxis is not possible – Coamoxiclav, levofloxacin etc.

Vaccine

When should we give the vaccine?

• Elective splenectomy: vaccine should be given two weeks before splenectomy.
• Emergency splenectomy: vaccine should be given two weeks after splenectomy.

What vaccine should we give?