Want to take quizzes and track your credits?
A man in his 50s presented with a history of pruritic lesions of the lower legs over the past 15 years that were unresponsive to topical corticosteroid therapy. On examination, he had multiple lichenified and ulcerated papules and nodules, some of them grouped in plaques located on the medial aspect of both shins (Figure, A). Occasional tense blisters were also seen (Figure, B). The patient’s family history was significant for similar cutaneous lesions in his father, brother, and cousin. Mild toenail dystrophy was also observed. A punch biopsy from the shin for histopathologic examination was performed (Figure, C and D).
Please finish quiz first before checking answer.
Read the answer below and download your certificate.
Read the discussion below and retake the quiz.
C. Pretibial epidermolysis bullosa
Histopathologic examination showed dermoepidermal detachment and scarce lymphohistiocytic inflammatory infiltrate in perivascular distribution in papillary dermis. Given the clinicopathological suspicion of pretibial epidermolysis bullosa (PEB), a genetic study was requested, which confirmed a heterozygous pathogenic sequence variation in the protein p.Lys2562Asn from the COL7A1 gene (OMIM 120120). The same variant was found in his 14-year-old son, who remains asymptomatic, while the rest of the family could not be reached.
Pretibial epidermolysis bullosa is an uncommon variant of dystrophic epidermolysis bullosa first described in 1946 by Kuske.1 It is characterized by the presence of localized pretibial lesions, with blisters and erosions, scarring, and atrophic or lichenoid papules or plaques. This mechanobullous genodermatosis results from sequence variations occurring in the COL7A1 gene. The latter encodes type VII collagen, the main constituent of the anchoring fibrils, which participate in the adherence of the lamina densa to the epidermis. The exact pathophysiological mechanism of PEB remains unknown, but some in vitro studies found an association between the peculiar phenotype of PEB and increased endoplasmic reticulum stress in keratinocytes.2
Sign in to take quiz and track your certificates
JN Learning™ is the home for CME and MOC from the JAMA Network. Search by specialty or US state and earn AMA PRA Category 1 CME Credit™ from articles, audio, Clinical Challenges and more. Learn more about CME/MOC
Corresponding Author: Eva M. Sánchez-Martínez, MD, Department of Dermatology, Hospital Universitario Doctor Peset, C/ Juan de Garay 21, 46017 Valencia, Spain (firstname.lastname@example.org).
Published Online: June 9, 2021. doi:10.1001/jamadermatol.2021.1785
Conflict of Interest Disclosures: None reported.
Additional Contributions: We thank the patient for granting permission to publish this information.
You currently have no searches saved.