Sickle cell disease (SCD) is a genetic condition presenting a wide variety of clinical manifestations, severe complications, and sequelae across all age groups, significantly impacting patients’ quality of life. Despite this, little is known about the predictive factors of severity that could be prevented with specific therapies. One of the major complications associated with SCD is leg ulcers, characterized by painful, hard-to-heal wounds that can occur spontaneously or after local trauma. The aim of this study is to discover potential biomarkers for complications in patients with sickle cell disease.

The study was an exploratory, descriptive, and analytical project nested within a Brazilian cohort of fully genotyped SCD patients from the REDS (Recipient Epidemiology and Donor Evaluation Study) program. For the pilot study, 15 serum samples were used, divided into three groups: healthy individuals (n = 5); SCD patients (n = 5); and SCD patients with leg ulcers (n = 5). For untargeted analysis, an Acquity UPLC MClass chromatograph coupled with a Synapt XS mass spectrometer was used. The metabolomic profile was aligned and analyzed using Progenesis QI software, while compound identification was based on the Human Metabolome Database (HMDB). Statistical analysis began with a cohort description to identify potential biomarkers associated with SCD, followed by multivariate analysis of raw mass spectrometry data. The generated data matrix was analyzed using EZinfo software, with unsupervised segregation through principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA).

Preliminary results showed significant differences in the metabolic profiles of the studied groups. Principal component analysis (PCA) revealed distinct clustering among the phenotypic group profiles. Chromatograms from duplicate analyses demonstrated high reproducibility, identifying 12 potential biomarkers in positive mode and 18 in negative mode. p-Cresol sulfate stood out as a potential biomarker for differentiating SCD patients who developed leg ulcers from the other groups.

The findings of this study indicate significant variations in the metabolic profiles between SCD patients, with and without leg ulcers, and healthy individuals. The identification of p-cresol sulfate as a potential biomarker is relevant, suggesting a possible association between this metabolite and the formation of ulcers in SCD patients.

This preliminary study offers a promising insight into the metabolic mechanisms involved in ulcer formation in SCD patients. The identification of p-cresol sulfate as a potential biomarker provides a basis for future research aiming to validate these findings and develop new therapeutic strategies. Continuing this research could lead to significant improvements in the quality of life for SCD patients, especially those suffering from leg ulcers.