Children with sickle cell disease are at high risk of invasive bacterial infections, which may lead to serious complications. Preventive measures, including antibiotic prophylaxis and vaccination, have changed the epidemiology of these infections over time. New pneumococcal conjugate vaccines have recently become available, and updated data are needed to better understand which bacteria are currently responsible for invasive infections in this population.

The aim of this retrospective study is to describe the bacterial distribution of invasive bacterial infections in children with sickle cell disease in France between 2020 and 2025. The results may help improve knowledge of these infections and guide future prevention strategies, including antibiotic management and vaccination policies.

DREPIBAC is a retrospective, multicenter observational study conducted in French hospital centers following children with sickle cell disease. The study focuses on invasive bacterial infections occurring between January 1, 2020 and December 31, 2025.

Children with sickle cell disease are particularly vulnerable to invasive bacterial infections, especially infections caused by Streptococcus pneumoniae. Over the past decades, antibiotic prophylaxis and vaccination against Haemophilus influenzae type b and Streptococcus pneumoniae have modified the epidemiology of these infections. Previous European data suggested changes in the distribution of bacterial pathogens responsible for invasive bacterial infections in this population. In addition, the recent availability of new pneumococcal conjugate vaccines highlights the need for updated epidemiological data in France.

The primary objective of the study is to establish the bacterial distribution of invasive bacterial infections in children with sickle cell disease in France between 2020 and 2025. Secondary objectives include assessing correlations between the identified bacteria and children's clinical characteristics, evaluating the theoretical coverage of pneumococcal conjugate vaccines against Streptococcus pneumoniae serotypes responsible for invasive infections, and estimating the incidence of invasive bacterial infections in this population.

Data will be collected retrospectively from hospital medical records and entered into a secure REDCap electronic case report form by investigators from participating centers. Collected data will include demographic and clinical characteristics, sickle cell disease phenotype, vaccination status, infection characteristics, microbiological findings, laboratory data, treatment, hospitalization course, and outcomes. Data will be pseudonymized using a unique study code.

The expected sample size is approximately 300 children. Descriptive analyses will be performed to estimate the proportions of the different bacterial pathogens. Standard statistical methods will be used for categorical and continuous variables, and incidence calculations will be performed where appropriate.

Inclusion Criteria

• Children with sickle cell disease aged under 18 years
• Hospitalized between January 2020 and December 2025
• Hospitalized for an invasive bacterial infection clinically defined as meningitis, pleuropneumonia, osteoarticular infection, or primary bacteremia
• Bacterium identified by culture or PCR

Exclusion Criteria

• Opposition from the child or his/her parents
• Bacterium identified by serology
• Urinary tract infection

Children with sickle cell disease followed in participating French hospital centers