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BackgroundDiffuse hyperpigmentation with guttate hypopigmentation (DHGH) is a new acquired pigmentary disorder. Only a few cases have previously been reported in the Chinese population, in Chinese.ObjectivesTo summarise the clinical, dermoscopic, and histopathological findings of DHGH in the English literature, to improve the recognition and management of this condition.Materials & MethodsThis was a retrospective study to summarise the clinical, dermoscopic, and pathological findings of nine cases of DHGH.ResultsAll nine patients with DHGH were female. The age at onset varied from 6 to 24 years (median 17 years). Patients were generally in good health without systemic disease. The lesions were often generalised to the trunk and extremities without any discomfort. Typical lesions were characterised by multiple uniform hypopigmented spots, 2-5 mm in diameter, irregularly distributed over diffuse hyperpigmentation. Dermoscopy revealed multiple blurred patchy areas of brownish pigmentation, sparse linear and dotted vessels, and perifollicular pigmentation on a white to bright white background, surrounded by brown hyperpigmentation. Histopathological findings included mild abnormal pigment of the epidermis, focal vacuolar degeneration of the basal cells, mild pigment incontinence and perivascular lymphocytic infiltration in the dermis.ConclusionDHGH is a new entity with distinctive clinical manifestations that differ from those of other known pigmentary disorders. So far, DHGH has only been reported in the Chinese population. It may not be uncommon and has not received much attention due to the few reports. The aetiology and pathogenesis of DHGH are still unknown and require further investigation.