Pneumococcal-related Hemolytic Uremic Syndrome in the United Kingdom: National Surveillance, 2006-2016.

Background: children <5 years of age since the introduction of the 7-valent pneumococcal conjugate vaccine (PCV7) in 2006 and its replacement with the 13-valent pneumococcal conjugate vaccine (PCV13) in 2010 in the United Kingdom. Methods: Public Health England conducts enhanced national surveillance of invasive pneumococcal disease in England. Confirmed invasive pneumococcal disease cases diagnosed between September 1, 2006, and March 31, 2016, with hemolytic uremic syndrome reported as a complication were included in the analysis. Results: There were 54 cases of pHUS during the surveillance period, with a median age of 17 months. The incidence of pHUS was 0.25/100,000 during the PCV7 period and 0.08/100,000 during the PCV13 period (incidence rate ratio: 0.31; 95% confidence interval: 0.16-0.57; P < 0.0001). Twelve children (22%) had an underlying comorbidity before disease onset. Overall, 31 (57%) presented with lower respiratory tract infection, 14 (25%) with meningitis, 8 (15%) with bacteremia and 1 (2%) with septic arthritis. An empyema was reported in 26/31 children (84%) with lower respiratory tract infection and cerebral abscess in 5/14 children (36%) with meningitis. The main responsible serotypes were 19A (n = 20), 3 (n = 6), 7F (n = 5) and 33F (n = 4). Eight children (15%) died, including 6 with meningitis. Conclusions: pHUS continues to be associated with significant morbidity and mortality. The incidence of pHUS was significantly lower after PCV13 replaced PCV7 in the childhood immunization program. Currently, most cases are due to non-PCV13 serotypes.