Pyogenic sacroiliitis in children: don’t forget the very young

Pyogenic sacroiliitis (PS) is rare with less than 100 pediatric cases reported in the medical literature. To better characterize PS in the pediatric population, we investigated a series of children presenting with PS. Retrospective data analysis was done at an academic tertiary center between the years of 2000 and 2017. All hospitalized children ≤ 16 years of age with PS were evaluated. Of the 894 children hospitalized with osteoarticular infections, 18 were diagnosed with PS (2%) and are included in the review. Two clinically distinct groups were identified. PS in infants (n = 13, 72.2%, mean age 1.1 years) had an indolent course and a faster recovery without any bacterial source identified. In contrast, the group of older children (n = 5, 27.8%, mean age 11.6 years) had a more complicated course and a higher rate of identified bacterial infections.