Lack of significant skeletal changes after long-term, low-dose retinoid therapy: Case report and review of the literature

Background: Long-term systemic retinoid therapy has been associated with skeletal side effects. There have been reports of diffuse idiopathic skeletal hyperostosis (DISH) syndrome, calcification of ligaments, and osteoporosis, as well as premature fusion of epiphyses and modeling abnormalities of long bones, occurring in patients on chronic high-dose isotretinoin, etretinate, and acitretin therapy. Low-dose acitretin has been used for many years as monotherapy or in combination with other systemic therapies for psoriasis. Evidence to date suggests that the frequency of symptomatic bony effects is quite low in these patients. Objective: To present the radiologic findings of a patient on long-term, low-dose acitretin and etretinate and to review the literature on the radiologic evidence of skeletal side effects during retinoid therapy. Methods: Case report and literature search. Results: A patient on low-dose acitretin had no significant radiologic abnormalities associated with retinoid use after 9 years of treatment. A review of the literature revealed conflicting reports on the incidence of radiologic abnormalities in patients on retinoid treatment. Conclusion: The evidence to date does not substantiate a clear link between radiologic skeletal abnormalities and long-term, low-dose acitretin or etretinate therapy.