Revista da Sociedade Portuguesa de Dermatologia e Venereologia (Oct 2024)
The role of narrowband ultraviolet B phototherapy in the treatment of refractory osteomalacia
Abstract
Osteomalacia is a disorder of mineralization of newly formed osteoid that can be precipitated through mechanisms that result in hypocalcemia, such as prolonged vitamin D deficiency. Treatment is mainly focused on vitamin D supplementation; however, it can be largely ineffective in malabsorption syndromes. Targeted phototherapy is the localized delivery of ultraviolet light largely used in Dermatology to treat several skin diseases. It is also known that ultraviolet B radiation increases serum 25-hydroxyvitamin D levels. Although its role in the treatment of vitamin D deficiency is largely based on clinical experience,it should be considered, particularly in refractory cases. We report a 60-year-old female with osteomalacia secondary tovitamin D deficiency due to malabsorption after gastric bypass surgery. High dose supplementation of vitamin D and calciumwas largely ineffective. Narrowband ultraviolet B was initiated resulting in marked clinical response and normalization of25-hydroxyvitamin D serum levels.