White Macule

CLINICAL DIAGNOSTIC MANUAL

A white macule is a flat skin lesion, lighter in colour than the surrounding skin, and can vary in size and shape. These macules result from a decrease or absence of melanin in the epidermis. Evaluating white macules is crucial to identify their underlying cause and determine whether they are part of a benign condition or require medical intervention.

Pathology	Symptoms and Clinical Signs	Suspected Diagnosis	Confirmatory Diagnosis
Post-inflammatory hypopigmentation	White macules in areas previously inflamed or injured. History of trauma, dermatitis, or previous infections.	Medical history and physical examination. Wood’s lamp.	Confirmation with medical history and physical examination.
Vitiligo	White, symmetrical, progressive macules. Common in sun-exposed areas, hands, feet, face, and genitals.	Medical history and physical examination. Wood’s lamp.	Confirmation with skin biopsy and histopathological analysis.
Pityriasis versicolor	Hypopigmented or hyperpigmented, scaly macules. Common on the trunk and upper limbs.	Medical history and physical examination. Wood’s lamp.	Confirmation with positive KOH microscopy for hyphae and spores.
Pityriasis alba	Hypopigmented macules, usually on the face. Common in children and adolescents.	Medical history and physical examination. Wood’s lamp.	Confirmation with medical history and physical examination.