Alopecia syphilitica with detection of Treponema pallidum in the hair follicle

Abstract

Alopecia is one of the clinical manifestations of secondary syphilis. It is uncommon for hair loss to be the sole or predominant manifestation, as hair loss is the chief clinical and histologic differential diagnosis of alopecia areata. The main difference between these two entities is the detection of Treponema pallidum in syphilis. We present the case of a 24-year-old Hispanic man, human immunodeficiency virus seropositive in treatment, with tiny patches of non-cicatricial alopecia in the parieto-occipital regions of his scalp. The patient denied previous history of genital or other skin lesions. A biopsy from an alopecic patch was performed which showed an inflammatory non-scarring alopecia with a discrete lymphocytic type inflammatory infiltrate localized in the peribulbar region. There was lymphocyte exocytosis into the matrix, associated with vacuolar degeneration, and scattered apoptotic cells were observed. Plasma cells were scattered. Immunohistochemical studies showed the presence of T. pallidum limited to the peribulbar region and penetrating into the follicle matrix. To the authors' knowledge, this is the first time that spirochetes have been shown in the hair follicle in alopecia syphilitica, suggesting that the spirochetes may be pathogenetic and responsible for the alopecia.

The clinical and trichoscopic features of syphilitic alopecia

“…and perifollicular (especially in the peribulbar region) lymphocytic dermal infiltration with scattered plasma cells was observed in some cases. 5,11,12 Besides, Treponema pallidum DNA was detected in lesional follicles of SA by molecular methods, 5 and immunohistochemistry showed the presence of spirochetes in hair follicles, usually in the perifollicular and peribulbar regions. 11 The above histopathological findings in SA lesions differ from AA, tinea capitis and trichotillomania, useful in differential diagnosis.…”

Hair and Scalp Manifestations in Secondary Syphilis: Epidemiology, Clinical Features and Trichoscopy

“…Our hypothesis is that this scalp discoloration can be caused by a small-vessel vasculitis limited to restricted areas of the scalp, due to the immune response to the local presence of Treponema pallidum . The presence of the bacterium in perifollicular areas as well as in hair follicles affected by SA has recently been documented, suggesting Treponema 's tropism for blood vessels and the perifollicular epithelium [2,12]. The immune response to T. pallidum , or the presence of the bacterium itself, could cause vasculitis and hair follicle sufferance, with loss of terminal hair and arrested follicle cycle (lag phase or kenogen [13]), resulting in empty follicles or in follicular ostia only vellus hair.…”

Nichtvirale sexuell übertragene Infektionen – Epidemiologie, Klinik, Labordiagnostik und Therapie

“…Ein diffuser Haarausfall kann im Einzelfall auch ein toxisches Telogeneffluvium bei Syphilis sein. Man weiß heute, dass es eine direkte Beteiligung von T. pallidum am Haarausfall gibt [37].…”