Oportunistic post splenectomy infection

Describes life treatening complication after splenectomy done for emergency and,or elective diseases, gram negative capsulated microorganisms that leads to this septic condition.
Also describes prevention with vaccination and prophylactic antibiotics and also treatment needed.

1. Overwhelming Post splenectomy Infections (OPSI) Riyad. A ( SR II) Medic Alert Bracelets 1

2. Overview of the presentation Introduction Epidemiology and Risk Factors Pathophysiology and Clinical presentation Prevention and treatment Summary References 2

3. Introduction Spleen is the largest Lymphoid organ The spleen plays a vital, although not indispensable , role in host defense. Both innate and adaptive immune responses occur within the spleen. Filter the circulating microorganism and their products Produce antibody to enhance immune response Around 25,000 splenectomies are being done annually in USA 3

4. Overwhelming post-splenectomy infection ” (OPSI) Is a rare but rapidly fatal infection syndrome occurring splenectomized or hypo splenic individuals Estimated incidence of OPSI is around 0.23 – 0.42% per year , with a lifetime risk of 5% The risk of OPSI has been reported potentially life-long Has high mortality rate of up to 50% to 70 % despite maximal treatment 4

5. Etiology OPSI is typically caused by encapsulated organisms, such as Streptococcus pneumoniae Neisseria meningitidis, and Haemophilus influenzae. Others- malaria and babesiosis are also known to affect asplenic patients more severely Capnocytophaga canimorsus has been recognized as causing OPSI after dog bites 5

6. The risk infection depends on : Underlying indication for splenectomy Higher in subjects received splenectomy for hematologic disorders and malignancy than post traumatic Age at splenectomy patients younger than 16 y (particularly younger than 5 y) Ongoing immune suppression Pt on chemotherapy Transplant recipients and GVHD 6

7. Clinical Presentations Typically begins as flue-like illness with a prodromal phase characterized by Fever, rigors, and chills Other nonspecific symptoms, including sore throat, malaise, myalgias, diarrhea, and vomiting. Pneumonia and meningitis may be present. Many patients have no identifiable focal site of infection and present only with high-grade primary bacteremia. 7

8. Cont. The clinical course may rapidly progress to coma and death within 24 to 48h, due to the high incidence of Shock Hypoglycemia Marked acidosis Electrolyte abnormalities Respiratory distress, and Disseminated intravascular coagulation (DIC). 8

9. Prevention and Treatment The current mainstays of post splenectomy care include: 1) Vaccinations 2) Patient and family education 3) Prophylactic antimicrobial therapy in selected people 4) Early empirical antimicrobial therapy for febrile episodes 5) early management of animal bites 6) Malaria prophylaxis for travelers in endemic countries 9

10. Immunization Current standard of care for post splenectomy pts are vaccination with: Polyvalent pneumococcal vaccine (PPV23), H. influenzae type b conjugate, and Meningococcal polysaccharide vaccine Influenza virus vaccine annually 10

11. Ideally patients should receive pneumococcal vaccine from 4 to 6 weeks before elective splenectomy or initiation of chemotherapy or radiotherapy. If it is not possible, at least 2 weeks pre-operatively in elective cases or at least 2 weeks post-operatively in emergency cases . In case of chemotherapy or radiotherapy administer vaccines at least 2 weeks before treatment or 3 months after. 11

12. CDC Recommendations of vaccination for splenectomized Pts 12

13. Routine revaccination of immunocompetent persons is not recommended by CDC. Revaccination with PPV23 is recommended for high-risk individuals: Persons who received the 14-valent vaccine Adults at highest risk who received the 23-valent vaccine 6 years prior Adults at highest risk who have shown a rapid decline in pneumococcal antibody levels Children at highest risk who would be 10 years old at revaccination 13

14. Antibiotics Antibiotic prophylaxis in post splenectomy patients controversial Currently, the international guidelines recommend antibiotic prophylaxis in children younger than 5 y of age with asplenia for any reason. Especially for the first two years after splenectomy Conversely, there is no evidence available to support the efficacy of antibiotic prophylaxis in adults Currently it is recommended that chemoprophylaxis in adults should be limited to a supply of standby antibiotics . 14

15. Education 15

16. Management Treatment need prompt and aggressive interventions as per severe sepsis protocol Early aggressive empirical antimicrobial therapy with both gram positive and negative coverage Current literature suggests a combination of i.v. vancomycin and ceftriaxone in combination with early goal directed therapy ICU admission and aggressive support. 16

17. Summery OPSI is the most fatal but potentially preventable infection The risk of OPSI is life long All patients who are undergoing splenectomy or with hyposplenic state should get vaccinated according to updated recommendation Splenectomized adult patients should have a supply of standby antibiotics to take at the onset of acute febrile episodes Vaccination and antibiotic prophylaxis are not 100% proctective The should be advised to carry an up to date vaccination card and wear Medic Alert Bracelets all the time 17

18. References Sabiston Textbook of Surgery 20 th Edition Maingot's Abdominal Operations 13 th edition International Journal of Surgery 12 (2014) 1314e1316 Infection and Drug Resistance 2019:12 2839–2851 Clinical Infectious Diseases® 2016;62(7):871–8 TAYLER AND FRANCIS GROUP HUMAN VACCINES & IMMUNOTHERAPEUTICS 2017, VOL. 13, NO. 2, 359–368 Hashimoto N. Management of Overwhelming Post splenectomy Infection Syndrome. Clin Surg. 2016; 1: 1148. 18