Serious Bacterial Infection (Meningitis/Sepsis) in Patients with Asplenia Syndrome: the importance of early diagnosis and the consideration of the prevention with vaccines

Abstract

Background: Patients with asplenia are at an increased risk for bacterial infections and are especially susceptible to Streptococcus pneumoniae infections, which sometimes lead to fatal consequences. In 2010, 7-valent pneumococcal conjugate vaccine was introduced in Japan, and it was expected to have protective effects against S. pneumoniae infections.
Method: We retrospectively investigated the clinical course of 7 patients with asplenia syndrome who had a serious bacterial infection (meningitis/sepsis) in the era before 7-valent pneumococcal conjugate vaccine was available.
Results: Serious bacterial infections were identified in 7 out of 44 (16%) patients with asplenia syndrome. The age range at the bacterial infection onset varied between 3 months to 4 years, and 5 out of 7 patients were at <2 years of age. Initial symptoms were non-specific in all patients that included fever, ill humor, and poor appetite. However, the patientʼs health deteriorated rapidly, and symptoms at admission entailed cardiopulmonary arrest, shock, and unconsciousness. The mortality rate was 57%.Streptococcus pneumoniae was the pathogen responsible for the infection in 5 out of 7 (71%) patients. Some of these patients could have been protected against the infection if they had been inoculated with 7-valent pneumococcal conjugate vaccine.
Conclusion: Serious bacterial infection (meningitis/sepsis) in patients with asplenia syndrome is associated with rapid health deterioration and a high mortality rate. Early diagnosis is difficult in these cases, and the education of all medical staff andpatient families is essential. Patients with asplenia syndrome should receive the 7-valent pneumococcal conjugate vaccine as soon as possible.