Discussion and conclusion
LPP is a scaring alopecia presents as patchy or diffuse hair loss perifollicular erythema, perifollicular scaling and follicular keratosis. It can be subdivided into 3 variants, including classic LPP FFA and Graham-Little-Piccardi-Lasseur syndrome (1).
FFA was first described in 1994 by Kossard as a progressive loss of frontotemporal hairlines in postmenopausal women (13). Although premenopausal women or even men might be affected, We found a high rate of premenopausal women affected by FFA (36.8%). In our series, we had 2 men (10.5%) that they presented more severe facial papules than women. Recently, involvement of facial vellus hairs presenting as peculiar facial papules have been reported in association with FFA. On the other hand the disease might extend beyond the frontotemporal hair line and affect peripheral body hair and lead to loss of eyebrows and eyelashes. Thus, FFA has been recognized as a generalized than localized process.
FFA may be associated with clinical or serologic evidence of autoimmunity e.g. hypothyroidism. In concordance with previous reports, we found a high prevalence of hypothyroidism. Among our patients there were 3 cases (15.7%) of hypothyroidism and 3 cases (15.7%) of vitamin D deficiency.
Facial vellus hair involvement present as noninflammatory facial papules has been described in association with FFA (8). The clinical picture includes follicular micropapules randomly distributed over the facial skin, readily more visible over temporal and cheek regions. At the scalp biopsy, an inflammatory lymphocytic infiltrate around the upper portion of hair follicle can been observed with common findings of perifolliculr lamellar fibrosis and fibrosis of follicular tract (15), so that it is considered as a variant of LPP.
In our experience these skin changes are more prominent in male patients due to terminal nature of facial hair follicles. In the other hand, aged patients may have subtle clinical expression because of coexisting wrinkles and solar elastosis. Premenopausal women present with more evident papules even before scalp or eyebrows alopecia.
In parallel our observation, Maele et al. have described facial LPP in the absence of FFA in premenopausal women (12). In current study we found facial LPP in 9 women (47.3% of our case) in the absence of scalp involvement whom 7 cases (41.17%) were premenopausal. Because of these findings this question comes to mind that whether these facial papules are in the clinical spectrum of FFA or a variant of LPP that can occur as a single presentation without involvement of other body sites. More studies and longer follow up studies are need to recognize the nature of these lesions.
In some studies, histological evaluation of these papules revealed elastic fiber involvement accompanied with preserved large sebaceous glands (16).
Retinoids including isotretinoin are known to have several actions include anti-inflammatory effects and induction of apoptosis in sebaceous glands. (17). There are some reports of successful treatment of FFA with topical retinoids (18). Also there is a report of successful treatment of facial papules in FFA with oral isotretinoin (16). In addition, we have never observed in our practice FFA or LPP patients using other treatments (for example hydroxychloroquine, cyclosporine, methotrexate and prednisolone) have improved their facial lesions.
These observations, prompted us to conduct this study to evaluate the therapeutic effects of oral isotretinoin as a first-line treatment of facial LPP. The results were promising, showed the facial papules dramatically disappeared (42.1%good and 26.3% very good response). It seems valuable to consider the use of oral isotretinoin for treatment of facial papules with LPP nature. But more studies with greater number patients are necessary to better evaluate the efficacy of oral isotretinoin optimum dosage and treatment duration and comparison between topical and systemic retinoids and long term fallow up of the patients and determining the incidence of recurrence after stopping the treatment.. On the other hand, isotretinoin-induced sebaceous gland atrophy is not permanent, so long-term follow-up is necessary to confirm our observations