Proopiomelanocortin (POMC) and psychodermatology.

Psychodermatology is the crossover discipline between Dermatology and Clinical Psychology and/or Psychiatry. It encompasses both Psychiatric diseases that present with cutaneous manifestations (such as delusional infestation) or more commonly, the psychiatric or psychological problems associated with skin disease, such as depression associated with psoriasis. These problems may be the result either of imbalance in or be the consequence of alteration in the homoeostatic endocrine mechanisms found in the systemic hypothalamic-pituitary-adrenal axis or in the local cutaneous corticotrophin-releasing factor-proopiomelanocortin-corticosteroid axis. Alteration in either of these systems can lead to immune disruption and worsening of immune dermatoses and vice-versa. These include diseases such as psoriasis, atopic eczema, acne, alopecia areata, vitiligo and melasma, all of which are known to be linked to stress. Similarly, stress and illnesses such as depression are linked with many immunodermatoses and may reflect alterations in the body's central and peripheral neuroendocrine stress pathways. It is important to consider issues pertaining to skin of colour, particularly with pigmentary disorders.