X-linked ichthyosis X-linked ichthyosis X-linked ichthyosis (XLI) (also known as ") is a skin condition caused by the hereditary deficiency of the steroid sulfatase (STS) enzyme that affects 1 in 2000 to 1 in 6000 males. XLI manifests with dry, scaly skin and is due to deletions or mutations in the "STS" gene. XLI can also occur in the context of larger deletions causing contiguous gene syndromes. Treatment is largely aimed at alleviating the skin symptoms. The term is from the Ancient Greek 'ichthys' meaning 'fish'. The major symptoms of XLI include scaling of the skin, particularly on the neck, trunk, and
Androgen-dependent condition Androgen-dependent condition An androgen-dependent condition, disease, disorder, or syndrome, is a medical condition that is, in part or full, dependent on, or is sensitive to, the presence of androgenic activity in the body. Known androgen-dependent conditions include acne, seborrhea, androgenic alopecia, hirsutism, hidradenitis suppurativa, precocious puberty in boys, hypersexuality, paraphilias, benign prostatic hyperplasia (BPH), prostate cancer, and hyperandrogenism in women such as in polycystic ovary syndrome (PCOS). Such conditions may be treated with drugs with antiandrogen actions, including androgen receptor antagonists such as cyproterone acetate, spironolactone, and bicalutamide, 5α-reductase inhibitors such as finasteride and dutasteride, CYP17A1 inhibitors such as abiraterone