label: Flexural reticulate hyperpigmentation
label_lc: flexural reticulate hyperpigmentation
description: Hyperpigmented macules with a reticulate (net-like) pattern involving the neck, axillae, groins, and other flexures like the inframammary folds in females. Histopathology shows orthokeratosis or hyperkeratosis, thinning of the suprapapillary epithelium, elongation of the rete ridges, hyperpigmentation of the basal layer, and follicular cysts. A perivascular lymphohistiocytic infiltrate can be observed in the papillary dermis.