Ganapathineedi Bindu, Mehta Alaap, Dande Susmitha, Shinde Anjali, Barsky Gary, Sebro Nadew
Department of Internal Medicine, Mount Sinai Hospital, Chicago, IL, USA.
Department of Pathology, Mount Sinai Hospital, Chicago, IL, USA.
Am J Case Rep. 2019 Feb 18;20:212-218. doi: 10.12659/AJCR.911422.
BACKGROUND The hallmark of bullous pemphigoid (BP) is widespread tense blisters arising on normal or erythematous skin, often with marked pruritus, the diagnosis of which is confirmed by direct immunofluorescence (DIF). BP is an autoimmune process that can be induced, though rarely, by medications. Drug-induced BP often has atypical clinical presentation, which requires a good understanding of other dermatological conditions with similar presentations, in particular, bullous subtype of erythema multiforme. End organ involvement warrants differentiating it from one of the severe cutaneous adverse reaction (SCAR) syndromes. CASE REPORT A 76-year-old African American male presented with extensive targetoid purplish skin lesions that clinically resembled atypical erythema multiforme, and one tense blister that raised a concern for BP. The patient presented 6 weeks after treatment with cephalexin for a urinary tract infection. Initial workup showed serum eosinophilia, acute kidney injury and eosinophiluria requiring deliberations on SCAR syndromes. A skin biopsy at an intralesional location showed a negative DIF, however, a skin biopsy at a perilesional site showed a positive DIF, confirming the diagnosis of BP. CONCLUSIONS This case demonstrates an atypical presentation of BP induced by drugs. It emphasizes the need for a greater level of awareness of diagnosis and treatment of the various entities that fall under adverse drug reactions in the elderly. It also highlights the need for appropriate choice of skin biopsy techniques (intralesional versus perilesional) to avoid misdiagnosis, as well as lessons on how to approach dermatologic conditions with end organ involvement for hospitalists and other medical professionals who routinely deal with undifferentiated disease conditions.
大疱性类天疱疮（BP）的特征是在正常或红斑皮肤上出现广泛的紧张性水疱，常伴有明显瘙痒，其诊断通过直接免疫荧光法（DIF）得以证实。BP是一种自身免疫性疾病，虽很少见，但可由药物诱发。药物性BP通常具有非典型临床表现，这需要充分了解其他具有相似表现的皮肤病，尤其是多形红斑的大疱型。终末器官受累需要将其与严重皮肤不良反应（SCAR）综合征之一相鉴别。病例报告：一名76岁非裔美国男性出现广泛的靶形紫色皮肤损害，临床上类似非典型多形红斑，还有一个紧张性水疱，这引发了对BP的担忧。该患者在因尿路感染接受头孢氨苄治疗6周后就诊。初始检查显示血清嗜酸性粒细胞增多、急性肾损伤和嗜酸性粒细胞尿，需要对SCAR综合征进行评估。病损内取材的皮肤活检显示DIF阴性，然而，病损周围部位的皮肤活检显示DIF阳性，从而确诊为BP。结论：本病例展示了药物诱发BP的非典型表现。它强调需要提高对老年人药物不良反应中各类疾病诊断和治疗的认识水平。它还突出了需要正确选择皮肤活检技术（病损内取材与病损周围取材）以避免误诊，以及为住院医师和其他经常处理未分化疾病状况的医学专业人员提供如何处理伴有终末器官受累的皮肤病的经验教训。
