Cutaneous acneiform eruptions are a side effect of many medications, including vitamin B12 therapy. However, reports of vitamin B12–induced acne are rare. We present a 67-year-old woman with a new diagnosis of pernicious anemia who developed a sudden acneiform eruption on the face after treatment with high-dose vitamin B12. Other medications that have been implicated in drug-induced acne include but are not limited to steroids, antibiotics, immunosuppressants, biologics, and vitamin B1 and B6. The pathogenesis is likely due to a transcriptome change in Propionibacterum acnes, the organism responsible for acne vulgaris. Cessation of the offending agent leads to a regression in symptoms.

We report a case of a 63-year-old man with a history of numerous basal cell carcinomas (BCCs) on vismodegib who developed a pink subcutaneous nodule that was thought to be either a BCC or an epidermal inclusion cyst. Sections displayed a dome-shaped lesion composed of large dermal nodules of epithelioid cells with variable cytology. Some of the dermal nodules demonstrated squamatization of the epithelioid cells while others had a predominantly basaloid phenotype. Central necrosis was present in the majority of the large dermal nodules, but the lesion did not stain with CK7 or CK20, helping to rule out internal metastases. The epithelial nodules stained strongly with pancytokeratin (AE1/AE3), p40, and stained lightly with BCL-2, supporting the diagnosis of BCC. However, Ber-EP4 being negative and the presence of significant squamatization suggest vismodegib can alter both the histological and immunophenotype of BCCs. This phenomenon has rarely been reported in literature. 

Takayasu arteritis is a rare vasculitis commonly seen in young women. Amaurosis fugax and headache are visual presentations of Takayasu arteritis. Migraine with visual aura is a common condition affecting young women, and differentiating migraine from Takayasu presenting with visual symptoms and headache can be challenging. We present a case of a young woman initially misdiagnosed with migraine with aura, who was later found to have Amaurosis fugax as an early manifestation of Takayasu arteritis.