Reflectance confocal microscopy and histological features of depigmentation after local corticosteroid injection

Abstract

Background Clinically, depigmentation after local corticosteroid injection is not rare. But there are less articles about its reflectance confocal microscopy (RCM) and histological features. This study aimed to define the RCM features and histopathologic findings of hypopigmentation after local corticosteroid injection and to analyze the correlations between the above two methods. Methods Forty cases with hypopigmentation after local corticosteroid injection were used to analyze the clinical and RCM features. Subsequently, for 20 of 40, an excision biopsy of the same imaged areas for histopathologic examination was executed. Results Our results showed that all 40 cases had round or ellipse hypopigmented macules with obscure boundary and 26 of 40 lesions’ long diameter went along limbs. The RCM features and the histological findings revealed all patients had variable degrees of epidermal thinning, flattening rete ridges, reduced melanin, and no inflammatory cell infiltration. MART‐1 analysis revealed the number of melanocytes was normal but with no or less melanin by Fontana‐Masson staining. Conclusions Depigmentation after local corticosteroid injection was a kind of disease with intact melanocytes, whose function was impaired. RCM features offer a high consistency with histopathologic findings. It thus constitutes a promising adjuvant tool for its diagnosis and for therapeutic follow‐up.

Hypopigmentation and subcutaneous fat atrophy associated with corticosteroid injection: a case report

“…23 Application of vitamin E paste and exposure of narrow ultraviolet rays for half a year were used to treat hypopigmentation in the study by Gu et al However, this treatment yielded a slow regression (82.50%) or consistent result (17.50%) in a year of follow-up duration. 25 Fat grafting, serial normal saline infiltration, and temporal fascia implantation are a few of the treatment options that may be considered with regard to refractory subcutaneous fat atrophy. 23 Subcutaneous fat atrophy and skin hypopigmentation associated with triamcinolone injection have been reported to affect several injection sites, depending on the location of the injection.…”

“…This might be caused by inhibition of prostaglandin or cytokine production in epidermal cells and suppression of a secretory metabolic product from melanocytes. 16,25 Concerning subcutaneous fat atrophy, it has been suggested that the corticosteroids have antiproliferative effects on keratinocytes and fibroblasts. It is also known that corticosteroid alters the metabolism of extracellular matrix proteins and the synthesis of lipids in the skin.…”

“…14 Injecting triamcinolone 40 mg/mL carries a substantially higher risk compared with injecting 10 mg/mL. 25 Dexamethasone and soluble betamethasone can be considered to be a more appropriate option when subcutaneous fat atrophy and skin hypopigmentation are the issues to be concerned. 17 Ultrasonography guidance is commonly used in musculoskeletal pain management.…”