Brown Macule

CLINICAL DIAGNOSTIC MANUAL

A brown macule is a flat, brown skin lesion that can vary in size and shape. These macules are caused by an accumulation of melanin in the epidermis or dermis and can result from various physiological or pathological processes.

Brown macules can appear anywhere on the body, and their evaluation requires careful differentiation to identify their origin and determine whether they are benign or require further intervention.

Pathology	Symptoms and Clinical Signs	Suspected Diagnosis	Confirmatory Diagnosis
Flat mole	Flat brown lesion, usually asymptomatic. Well-defined borders.	Medical history and physical examination. Dermatoscopy.	Confirmation with physical examination and dermatoscopy.
Freckles (ephelides)	Small brown macules, more pronounced with sun exposure. Common in fair-skinned individuals.	Medical history and physical examination. Evaluation of sun exposure.	Confirmation with medical history and physical examination.
Solar lentigines (sunspots)	Large brown macules caused by chronic sun damage. Common in sun-exposed areas.	Medical history and physical examination. Evaluation of sun exposure.	Confirmation with medical history and physical examination.
Chloasma (melasma)	Hyperpigmented macules on the face, especially on the cheeks, forehead, and upper lip. Associated with hormonal changes (pregnancy, contraceptives).	Medical history and physical examination. Evaluation of hormonal history.	Confirmation with medical history and physical examination.
Café-au-lait spots	Light brown macules with well-defined borders. May be present from childhood.	Medical history and physical examination. Evaluation of family history.	Confirmation with physical examination and genetic analysis if neurofibromatosis is suspected.
Pseudoacanthosis nigricans	Hyperpigmentation in skin folds. Common in individuals with obesity.	Medical history and physical examination. Evaluation of risk factors.	Confirmation with physical examination and weight management.
Acanthosis nigricans	Hyperpigmentation and skin thickening, especially in skin folds. Associated with insulin resistance.	Medical history and physical examination. Glucose and insulin resistance tests.	Confirmation with physical examination and laboratory tests (glucose, insulin).
Berloque dermatitis	Hyperpigmentation in areas exposed to perfumes or cosmetics. Linear or irregular lesions.	Medical history and physical examination. Evaluation of product exposure.	Confirmation with exposure history and response to product avoidance.
Photochemical plant hypersensitivity	Skin reaction after contact with phototoxic plants. Hyperpigmentation in sun-exposed areas.	Medical history and physical examination. Evaluation of plant exposure.	Confirmation with exposure history and dermatoscopy.
Hutchinson’s melanotic freckle	Benign pigmented lesion. Can be an early sign of lentigo maligna melanoma.	Medical history and physical examination. Dermatoscopy.	Confirmation with biopsy and histopathological analysis.
Peutz-Jeghers syndrome	Hyperpigmented macules on mucous membranes and skin. Associated with gastrointestinal polyps.	Medical history and physical examination. Evaluation of family history.	Confirmation with genetic analysis and endoscopic evaluation of polyps.