A 30-year-old woman presented with bilateral wrist pain that began about eight months earlier. The pain progressed in severity and was associated with tingling, numbness, weakness, and aching in both forearms. The patient used a thumb spica splint at night with occasional but inconsistent relief. The pain did not improve after treatment with oral and topical analgesics. After pain onset, areas of skin discoloration developed on both wrists. The patient had no occupational exposures and had not used any new skin products. She had no relevant family history.

Physical examination revealed bilateral 3- to 4-cm nonraised, nonscaly, hypopigmented patches with irregular borders extending over the first dorsal compartments (Figure 1). There was a 1-cm bruise within the hypopigmented patch on the left side. The lesions were not pruritic or painful. The patient had no other skin rashes or lesions.

Question

Based on the patient’s history and physical examination findings, which one of the following is the most likely diagnosis?

• A. Chemical leukoderma.

• B. Intra-articular steroid injection hypopigmentation.

• C. Pityriasis versicolor.

• D. Vitiligo.