Incidence of invasive pneumococcal disease in immunocompromised patients: A systematic review and meta-analysis

Background: Invasive pneumococcal disease (IPD) is associated with high morbidity and mortality, with immunocompromised patients (ICPs) at particular risk. Therefore, guidelines recommend pneumococcal vaccination for these patients. However, guidelines are scarcely underpinned with references to incidence studies of IPD in this population. This, potentially results in unawareness of the importance of vaccination and low vaccination rates. The objective of this systematic review and meta-analysis was to assess the incidence of IPD in ICPs. Methods: We systematically searched PubMed and Embase to identify studies in English published before December 6th, 2017 that included terms related to 'incidence', 'rate', 'pneumococcal', 'pneumoniae', 'meningitis', 'septicemia', or 'bacteremia'. We focused on patients with HIV, transplantation and chronic inflammatory diseases. Results: We included 45 studies in the systematic review reporting an incidence or rate of IPD, defined as isolation of Streptococcus pneumoniae from a normally sterile site. Random effects meta-analysis of 38 studies showed a pooled IPD incidence of 331/100,000 person years in patients with HIV in the late-antiretroviral treatment era in non-African countries, and 318/100,000 in African countries; 696 and 812/100,000 in patients who underwent an autologous or allogeneic stem cell transplantation, respectively; 465/100,000 in patients with a solid organ transplantation; and 65/100,000 in patients with chronic inflammatory diseases. In healthy control cohorts, the pooled incidence was 10/100,000. Discussion: ICPs are at increased risk of contracting IPD, especially those with HIV, and those who underwent transplantation. Based on our findings, we recommend pneumococcal vaccination in immunocompromised patients.