Cutaneous manifestations of sickle cell disease: an updated review

Enhancing sickle cell leg ulcer healing with combined photodynamic and photobiomodulation therapies: A pilot experience

AIM

This study aimed to evaluate the safety and efficacy of combined photodynamic therapy (PDT) and photobiomodulation (PBM) in treating sickle cell leg ulcers (SCLUs), with a focus on pain reduction and enhanced healing.

MATERIALS AND METHODS

In this prospective, open-label, uncontrolled pilot study, ten SCD patients with 17 chronic leg ulcers received PDT and PBM treatments. Ulcer severity, pain levels, and microbiome changes were monitored, and clinical data were analyzed using appropriate statistical methods.

RESULTS

Among the treated ulcers, 64.7 % (11 out of 17) showed significant healing, with 9 ulcers achieving complete closure. The average reduction in ulcer size was significant, with a median healing time of 123 days. Pain levels decreased significantly in 82.3 % of treated ulcers (p < 0.001), and a 75.4 % reduction in bacterial load was observed, alongside increased microbiome diversity (p < 0.05). Elevated levels of IL-6 and PSGL-1 were associated with non-healing ulcers, indicating their potential as prognostic biomarkers.

CONCLUSION

The combined PDT and PBM therapy proved to be effective and safe for SCLUs, offering significant improvements in healing and pain reduction. These findings suggest that integrating PDT and PBM into standard care protocols could enhance the management of SCLUs.

Ferroptosis as an emerging target in sickle cell disease

Sickle cell disease (SCD) is an inherited hemoglobin disorder marked by red blood cell sickling, resulting in severe anemia, painful episodes, extensive organ damage, and shortened life expectancy. In SCD, increased iron levels can trigger ferroptosis, a specific type of cell death characterized by reactive oxygen species (ROS) and lipid peroxide accumulation, leading to damage and organ impairments. The intricate interplay between iron, ferroptosis, inflammation, and oxidative stress in SCD underscores the necessity of thoroughly understanding these processes for the development of innovative therapeutic strategies. This review highlights the importance of balancing the complex interactions among various factors and exploitation of the knowledge in developing novel therapeutics for this devastating disease.

The Curious Case of a Painful Leg Ulcer

Sickle cell disease is a condition that can involve numerous organ systems secondary to vascular occlusion. Herein, we present a case of a 21-year-old male with sickle cell disease requiring long-term hydroxyurea therapy. Upon migrating to the United States from Yemen, the patient developed a rapidly progressive, exquisitely painful ulcer on his right lower extremity. Given his country of origin, a broad differential, including select infectious diseases, was essential. Moreover, establishing the unequivocally correct diagnosis was crucial to determine proper and safe therapy. Ultimately, a lesional biopsy demonstrated numerous sickled red blood cells occluding blood vessels, leading to the diagnosis of sickle cell disease-related leg ulceration.

Mouse models of sickle cell disease: Imperfect and yet very informative

The root cause of sickle cell disease (SCD) has been known for nearly a century, however, few therapies to treat the disease are available. Over several decades of work, with advances in gene editing technology and after several iterations of mice with differing genotype/phenotype relationships, researchers have developed humanized SCD mouse models. However, while a large body of preclinical studies has led to huge gains in basic science knowledge about SCD in mice, this knowledge has not led to the development of effective therapies to treat SCD-related complications in humans, thus leading to frustration with the paucity of translational progress in the SCD field. The use of mouse models to study human diseases is based on the genetic and phenotypic similarities between mouse and humans (face validity). The Berkeley and Townes SCD mice express only human globin chains and no mouse hemoglobin. With this genetic composition, these models present many phenotypic similarities, but also significant discrepancies that should be considered when interpreting preclinical studies results. Reviewing genetic and phenotypic similarities and discrepancies and examining studies that have translated to humans and those that have not, offer a better perspective of construct, face, and predictive validities of humanized SCD mouse models.