BDNF and pachyonychia congenita: Participants underwent a comprehensive evaluation, including clinical assessments (demographic information, medical history, PC progression, and complications such as erectile dysfunction [IIEF-5] and urinary incontinence [ICIQ-UI]), biochemical testing (testosterone, prostate-specific antigen, phosphorylated neurofilament heavy chain [pNF-H], brain-derived neurotrophic factor [BDNF], neuroserpin [NSP], and interleukin-6 [IL-6]), and neuropsychological assessment of cognitive functions.