Impact of genotype on clinical course in sickle cell disease and the utility of neutrophil-lymphocyte ratio: a ten-year single-institution experience

ABSTRACT

Background

Sickle cell disease (SCD) is a diverse group of blood disorders with significant global disease burden. Contemporary interest in the underlying inflammatory paradigm of SCD has emphasized the role of the neutrophil–lymphocyte ratio (NLR) as a prognostic inflammatory marker.

Methods

We retrospectively reviewed 268 hospitalized patients with SCDs of different genotypes (HbSS, HbSβ⁰ thalassemia, HbSβ⁺ thalassemia, and HbSC), totaling 3329 hospital admissions over a 10-year period. Patients were stratified into SS/Sβ⁰ and Sβ⁺/SC groups for statistical analysis of parameters collected at steady state and at hospital admission.

Results

At steady state, per unit increase of hemoglobin values was associated with reduced odds of ≥ 2 hospital admissions per year in SS/Sβ⁰ and Sβ⁺/SC groups; per unit increase in platelet count and white blood cell count was associated with increased odds only in the SS/Sβ⁰ group. The NLR had no association in either group. During admission, a cutoff of NLR = 3.5 discerned infection with a sensitivity of 60% and specificity of 57%. Performance improved when excluding patients on outpatient hydroxyurea therapy (cutoff of NLR = 3.5; sensitivity of 68% and specificity of 64%).

Conclusion

This study supports the utility of NLR as an accessible adjunctive clinical tool in SCD prognostication.

KEYWORDS:

• Hemoglobinopathy
• infection
• neutrophil–lymphocyte ratio
• sickle cell anemia
• sickle cell disease

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Author contributions

A Mathavan and A Mathavan performed data collection and analysis, produced tables and figures, and drafted the manuscript. M Mathavan, U Krekora, AJ Winer, and E Altshuler performed data collection and analysis and drafted portions of ‘Results’ and ‘Discussion.’ All other authors performed data collection. JD DeLaune and MW Mandernach supervised the study, provided subject matter expertise, revised the manuscript, and are responsible for the final content. All authors have agreed on the journal to which the article will be submitted, the final version for publication, and accountability for all aspects of the work.

Acknowledgments

The authors thank Kriti Gera, MD for her assistance in editing and appraising collected steady-state data.

Ethical statement

Approval for this study was obtained from the University of Florida Institutional Review Board (IRB202102790). Patient consent was not required by the Institutional Review Board as all data was deidentified and the study was retrospective, involving no intervention. Patient data and confidentiality were respected in accordance with the Declaration of Helsinki.

Data availability statement

For original data, please contact [email protected].

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This paper was not funded.