|ORIGINAL CASE REPORT-OUT OF ORDINARY
|Year : 2019 | Volume
| Issue : 2 | Page : 39-40
Scabies surrepticius captured by dermoscope
Binrong Ye1, Zaishi Zhu2, Yeqiang Liu3
1 Department of Dermatology, Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, China
2 Department of Dermatology, Nanjing University of Traditional Chinese Medicine, Nanjing, Jiangsu, China
3 Department of Dermatopathology, Shanghai Skin Disease Hospital, Shanghai, China
|Date of Submission||11-Nov-2019|
|Date of Acceptance||23-Nov-2019|
|Date of Web Publication||08-Jan-2020|
Dr. Yeqiang Liu
Department of Dermatopathology, Shanghai Skin Disease Hospital, No. 1278, Baode Road, Zhabei District, Shanghai 200443
Source of Support: None, Conflict of Interest: None
Scabies is a common skin infection, but bullous scabies is not only rare but also easy to be misdiagnosed by clinicians. Dermoscope can rapid and accurately diagnose scabies, as well as bullous scabies. We report a case of bullous scabies diagnosed by dermoscopy.
Keywords: Benzyl benzoate, bullous scabies, dermoscope, scabies, scabies surrepticius
|How to cite this article:|
Ye B, Zhu Z, Liu Y. Scabies surrepticius captured by dermoscope. J Renal Nutr Metab 2019;5:39-40
Footnote from the Editor: This case is being reported to draw attention of nephrologists and immunologists to the possibility of scabies whenever a widespread erythematosquamous dermatosis develops in a case of SLE. Scabies can mimic several diseases, including cutaneous or systemic lupus erythematosus (SLE). The unusual clinical signs of scabies may be easily overlooked (Reference J. Fernando Val-Bernal, M. Carmen González-Vela, Sonsoles Yáñez, Concepción Mira Atypical Scabies In Systemic Lupus Erythematosus Annals of Saudi Medicine, 1998 Case Reports Vol 18, No 6)
| Introduction|| |
Scabies is a common contagious cutaneous disease, which often manifests itself in the form of erythematous excoriated papulovesicular rash, burrows, nodules, and hyperkeratotic lesions. Bullous scabies (BS) is a rare presentation of mite infestation without typical burrows, pruritic papules, and nodules. It was first described in 1974 by Samuel F Bean, a dermatologist in Houston, Texas, USA. BS may have been largely misdiagnosed or neglected as a diagnosis in China for a long time. We report a case of scabies presenting only as a blister with direct diagnostic evidence under dermoscopy.
| Case Report|| |
A 78-year-old male was consulted for skin problems in nursing homes. He had a mental disease, but no other systemic illness. Physical examination revealed a few scratches on his trunk and an intense blister on his right wrist [Figure 1]. A portable dermoscope (DL4D2035) revealed what the blister looked like: the image showed a white tunnel with a triangular seal at the end. Furthermore, indirect immunofluorescence testing was ordered which was found to be negative for circulating antibodies against bullous pemphigoid (BP) BP180 and BP230, indicating scabies surrepticius (BS). His pruritus and skin lesions resolved without recurrence following topical treatment with 25% benzyl benzoate solution twice a week.
|Figure 1: Physical examination revealed a few scratches on the patient's trunk and an intense blister on his right wrist (a). A portable dermoscope revealed what the blister looked like: the image showed a white tunnel with a triangular seal at the end (b)|
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| Discussion|| |
BS, also called BP-like eruption, is still going unheeded more likely to occur in men over the age of 70. There are several ways to detect scabies, including serological testing of immunoglobulin (Ig) E antibody. However, the diagnosis of BS remains challenging due to its tendency to mimic BP and is particularly difficult to diagnose when bullous lesions are the only manifestations. BS can clinically and immunohistochemically mimic the autoimmune blistering disorder BP. Dermoscopy is a highly sensitive and noninvasive method for diagnosing scabies. This visual positive test supports the hypothesis that the presence of scabies causes blisters. It is a pity that we did not conduct immunohistochemistry and direct immunofluorescence of the skin lesion because the patient refused to have a traumatic examination.
Although many theories have been tried to elucidate the etiology and pathogenesis of BS, they include autoeczematization, superinfection, the direct injury or secretion of lytic enzymes by the scabies mites, and cross-reactivity of scabies protein with basal membrane zone antigens. In our case, BP antibody was negative, and scratching did not elicit a positive Koebner sign, which is more likely to support the hypothesis that the presence of scabies is the direct cause of blisters. Previous reports of BS not responding to glucocorticoids, Ig, and cyclophosphamide also support this point. Antiscabies drugs were just as effective in our case as classic scabies treatments. In addition, this case highlights a fundamental principle of dermoscopy application, which is that dermoscopy should be applied to every skin lesion, not just clinically preselected cases.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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