Causes

LS is believed to be a Heterogeneous Condition (a condition that can be caused by multiple underlying disorders).

Pathways that might play a role in a patient's LS --alone or together.

1. Hormonal (especially in women with menopause)
2. Infection
3. Auto-immune.

Further reading: Understanding diseases as increased heterogeneity.

---

LS causes

In women, the etiopathogenesis of LS is very probably linked to autoimmune mechanisms, while in the men, this hypothesis seems less plausible [1,]. A broad study conducted on 350 women with LS highlighted that 21.5% had one or more diseases of an autoimmune type, 21% a family history of autoimmune diseases and 42% autoantibodies [3]. The most common autoimmune diseases were thyroiditis (12%), alopecia areata (9%), vitiligo (6%) and pernicious anaemia (2%) [4–8].

IgG1 autoantibodies directed against the glycoprotein of an extracellular matrix (ECM1) were found in the serum of about 70% of women with LS; however, even in the males, the concentration of anti-ECM1 antibodies was higher than in the controls in some recent clinical records reported in literature [9,]. There are, however, conflicting opinions concerning the true pathogenetic mechanism, since it would seem that the trigger is actually the local chronic irritation and that the auto-antibodies develop only later. It is well known that the anatomical presence of the foreskin facilitates the creation of a ‘damp’ environment and, consequently, the onset of local chronic irritative condition that, in turn, could lead to the formation of LS (LS is found only rarely in circumcised patients). The formation of autoantibodies would therefore more probably be a reactive ‘epiphenomenon’ (a secondary, accompanying occurrence) rather than a direct cause of the problem.

Other triggering factors could consist of some infectious agents (Borrelia) or traumatic events and/or outcomes of genital surgery [11–15] . Further etiopathogenetic theories are based on hormonal factors and, in this respect, significantly lower levels of dihydrotestosterone (DHT) were found in some LS patients [16]. (DHT is lowered by the hair-loss drug Finasteride (Propecia).) Furthermore, a histochemical assessment of androgen receptors, carried out on the skins of patients with LS, showed a reduction of these receptors [17]. Psychosomatic inductions are also identifiable as the trigger in the widespread erupting or episodically relapsing forms.

PDRN: Genital Lichen Sclerosus in Male Patients: A New Treatment with Polydeoxyribonucleotide, (2016)