Post-inflammatory hypopigmentation - Skin in Adult
While it can occur in patients of all ages and skin types, it is more pronounced in those with darker skin. This is attributable to the greater color contrast between the lesions and the patient's normal skin. The incidence is comparable in males and females. Predisposition is believed to be based on an individual's genetically predetermined melanocyte response to cutaneous inflammation. It can be seen as a sequela of many inflammatory skin diseases (atopic dermatitis, psoriasis, lichen striatus, pityriasis lichenoides chronicus, lichen planus, sarcoidosis, discoid lupus erythematosus), infections (zoster, pityriasis versicolor, impetigo), procedures (chemical peels, laser, dermabrasion), and burns.
Histopathology may be nonspecific and will vary depending on the underlying etiology. It will generally show decreased epidermal melanin with melanophages present in the upper dermis and variable superficial lymphohistiocytic infiltration.
Resolution of lesions is dependent on the underlying cause and degree of involvement, ranging from a few weeks in minimally hypopigmented lesions to several years in depigmented lesions (eg, discoid lupus erythematosus and burns).
L81.9 – Disorder of pigmentation, unspecified
277787003 – Post-inflammatory hypopigmentation
- Pityriasis alba – Scaly, oval, ill-defined macules and patches with mild hypopigmentation; more common in children.
- Sarcoidosis – Histology will reveal dermal noncaseating granulomas.
- Progressive macular hypomelanosis – Punctiform red fluorescence under Wood's lamp.
- Pityriasis versicolor – Coppery/orange under Wood's lamp; KOH prep of scale shows a characteristic "spaghetti and meatballs" appearance.
- Leprosy – Associated with hypoesthesia.
- Mycosis fungoides – Early-stage variant involving hypopigmentation on the trunk and extremities that may be pruritic.
- Scleroderma – Circumscribed hypopigmentation with perifollicular pigment retention.
- Hypopigmented lesions in extramammary Paget's disease
- Medication – Particularly high-potency topical and intralesional corticosteroids.
- Vitiligo – Pigment loss is total.
- Idiopathic guttate hypomelanosis
- Discoid lupus erythematosus – Pigment loss, often in the center of lesions with a rim of hyperpigmentation; associated with cutaneous atrophy/scarring.
- Chemical leukoderma – History of bleaching agents, phenol-containing cleaners, and glues.
- Depigmented extramammary Paget's disease