Validation and Application of a Predictive Score of Acute Chest Syndrome

Vaso-occlusive crisis (VOC) is the most common manifestation of sickle cell disease, and acute chest syndrome (ACS) is a frequent complication with a substantial risk of death. The aim of this study was to validate the previously developed PREdictive SEVerity (PRESEV) score for the occurrence of ACS in adult patients with sickle cell disease hospitalized for VOC and to assess the safety of outpatient management of patients with a low-risk score.

To validate the PRESEV score, a prospective observational study was conducted in 13 centers across 5 countries in Africa and Europe. The score ranges from 0 to 16, with values of 5 or less considered low risk. The safety of a low-risk score (≤5) for outpatient management was then assessed in 100 patients. The primary outcome was the occurrence of ACS.

A total of 393 patients were included for the validation of the score: 206 (52.4%) from Europe and 187 (47.6%) from Africa. Of these, 76 patients (19.3%) developed ACS. Of the 50 patients (12.7%) with a low-risk score, 3 (6.0%) developed ACS (negative predictive value 94.0%). Of the 76 patients who developed ACS, 73 (96.1%) did not have a low-risk score (sensitivity 96.1%). A total of five deaths (1.3%) was recorded; no individuals who died had a low-risk score. Score performance was similar across both continents. When the score was used to guide outpatient management in 100 patients with VOC, one case of ACS (1.0%) was recorded.

This international study validated the PRESEV predictive risk score to identify adult patients at low risk for ACS. (Funded by the Support for Actions against Red Blood Cell Diseases Association and others; trial registration number, IRB 00003835; ClinicalTrials.gov number, NCT03032055.).