International Journal of Trichology

CASE REPORT
Year
: 2012  |  Volume : 4  |  Issue : 3  |  Page : 172--173

Acantholytic hair casts: A dermoscopic sign of pemphigus vulgaris of the scalp


Rodrigo Pirmez 
 Department of Dermatology, Clementino Fraga Filho University Hospital, Federal University of Rio de Janeiro, Brazil

Correspondence Address:
Rodrigo Pirmez
Rua Professor Rodolpho Paulo Rocco, 255, Departamento de Dermatologia, Rio de Janeiro, RJ 21941-913
Brazil

Abstract

We report the dermoscopic features of pemphigus vulgaris (PV) involving the scalp of a 57-year-old African-American female. Among our findings, there were hair casts - movable tubular structures that envelop the hair shafts. We suggest that the development of those casts occurs through acantholysis within the outer root sheath, a mechanism not yet considered in the literature. This report also highlights how dermoscopy may contribute to the evaluation of disease activity, especially in those cases of PV in which scalp involvement is recalcitrant to treatment. Finally, we recommend that the presence of hair casts should herald the need of therapy adjustment for better disease control.



How to cite this article:
Pirmez R. Acantholytic hair casts: A dermoscopic sign of pemphigus vulgaris of the scalp.Int J Trichol 2012;4:172-173


How to cite this URL:
Pirmez R. Acantholytic hair casts: A dermoscopic sign of pemphigus vulgaris of the scalp. Int J Trichol [serial online] 2012 [cited 2022 Sep 28 ];4:172-173
Available from: https://www.ijtrichology.com/text.asp?2012/4/3/172/100087


Full Text

 Introduction



Hair casts are discrete, shiny, freely movable tubular structures that envelop the hair shafts and may clinically be misdiagnosed as nits. [1],[2] In 1986, Keipert considered the existence of two types of hair casts. [3] The first was associated with parakeratotic disorders of the scalp, such as psoriasis. He denominated them parakeratotic hair casts, reflecting the cause and composition of those casts. The second, not associated with scalp disorders, was described in women and named as peripilar keratin casts. The formation of hair casts is also a well-known feature of persistent traction and, recently, Tosti et al. described them as a helpful dermoscopic clue for the diagnosis of traction alopecia. [2]

 Case Report



We have detected hair cast formation in a 57-year-old African-American female with pemphigus vulgaris (PV) involving the scalp. She was in her second flare of the disease with widespread blister formation. On scalp examination, there was a painful, pruritic, large eroded hairless plaque covered with yellow to black crusts [Figure 1]a. Dermoscopy of the immediate perilesional area revealed hair shafts imprisoned underneath crusts and also numerous hair casts [Figure 1]b. These structures were a few millimeters long, but sometimes encircled the hair shaft through a longer extension. Pull test was strongly positive and examination of the epilated hairs under dermoscopy showed pigmented roots with sheaths, corresponding to normal anagen hairs [Figure 1]c. Direct immunofluorescence of plucked hairs of patients with PV reveals IgG and C3 deposition on outer root sheath (ORS) keratinocytes. [4] This exam was not available at that time.{Figure 1}

 Discussion



Different patterns of hair loss have been reported in PV, including anagen shedding, [5] as observed in our patient, scarring alopecia, [6] and tufted folliculitis. [7] Some authors suggest that the scarring would result from the combination of acantholysis and secondary bacterial infection. [7] Telogen effluvium has been described in mice; [8] however, it is not a feature of the disease in humans.

Hair cast development in PV is possibly due to a mechanism not enclosed in Keipert's classification - acantholysis within the ORS. As the hair grows, part of the ORS keratinocytes is carried up through the follicular ostia to form a cylindrical structure enveloping the shaft: the hair cast. Like anagen shedding, hair casts in PV suggest a subclinical involvement of the hair follicle. Delmonte et al. considered the former as a Nikolsky sign of the scalp. [5] In our opinion, acantholytic hair casts should be regarded likewise.

To our knowledge, this is the first report of dermoscopic features of PV involving the scalp. This case also highlights how dermoscopy may contribute to the evaluation of disease activity, especially in those cases of PV in which scalp involvement is recalcitrant to treatment. The presence of hair casts should be regarded by the dermatologist as a sign that acantholysis is still taking place, and possibly herald the need of therapy adjustment for better disease control.

References

1Kohn SR. Hair casts or pseudonits. JAMA 1977;238:2058-9.
2Tosti A, Miteva M, Torres F, Vincenzi C, Romanelli P. Hair casts are a dermoscopic clue for the diagnosis of traction alopecia. Br J Dermatol 2010;163:1353-5.
3Keipert JA. Hair casts. Review and suggestion regarding nomenclature. Arch Dermatol 1986;122:927-30.
4Daneshpazhooh M, Asgari M, Naraghi ZS, Barzgar MR, Akhyani M, Balighi K, et al. A study on plucked hair as a substrate for direct immunofluorescence in pemphigus vulgaris. J Eur Acad Dermatol Venereol 2009;23:129-31.
5Delmonte S, Semino MT, Parodi A, Rebora A. Normal anagen effluvium: a sign of pemphigus vulgaris. Br J Dermatol 2000;142:1244-5
6Lapière K, Caers S, Lambert J. A case of long-lasting localized pemphigus vulgaris of the scalp. Dermatology 2004;209:162-3.
7Jappe U, Schroder K, Zillikens D, Petzoldt D. Tufted hair folliculitis associated with pemphigus vulgaris. J Eur Acad Dermatol Venereol 2003;17:223-6.
8Koch PJ, Mahoney MG, Cotsarelis G, Rothenberger K, Lavker RM, Stanley JR. Desmoglein 3 anchors telogen hair in the follicle. J Cell Sci 1998;111(Pt 17):2529-37.