Acne as a chronic systemic disease.

Acne is the most common skin disorder. In the majority of cases, acne is a disease that changes its skin distribution and severity over time; moreover, it can be a physically (scar development) and psychologically damaging condition that lasts for years. According to its clinical characteristics, it can be defined as a chronic disease according to the World Health Organization criteria. Acne is also a cardinal component of many systemic diseases or syndromes, such as congenital adrenal hyperplasia, seborrhea-acne-hirsutism-androgenetic alopecia syndrome, polycystic ovarian syndrome, hyperandrogenism-insulin resistance-acanthosis nigricans syndrome, Apert syndrome, synovitis-acne-pustulosis-hyperostosis-osteitis syndrome, and pyogenic arthritis-pyoderma gangrenosum-acne syndrome. Recent studies on the Ache hunter gatherers of Paraguay detected the lack of acne in association with markedly lower rates of obesity, diabetes mellitus, hyperlipidemia, and cardiovascular diseases, a finding that indicates either a nutritional or a genetic background of this impressive concomitance.