Diffuse hyperpigmentation with guttate hypopigmentation: a new pigmentary disorder.

Diffuse 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. To summarise the clinical, dermoscopic, and histopathological findings of DHGH in the English literature, to improve the recognition and management of this condition. This was a retrospective study to summarise the clinical, dermoscopic, and pathological findings of nine cases of DHGH. All 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. DHGH 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.

Targetoid haemosiderotic nevus: four cases and a literature review.

BACKGROUND: Targetoid haemosiderotic nevus (THN), a distinct clinical form of melanocytic nevus, is characterized by the sudden development of a purpuric halo surrounding a pre-existing nevus, easily mistaken for melanoma. OBJECTIVES: To summarise the clinical, dermoscopic and histopathological findings of THN in order to better recognize and manage this condition. MATERIALS & METHODS: We describe four cases and provide a review of the literature based on a search in PubMed. Overall, the clinical, dermoscopic and pathological findings of 15 THN cases are summarised. RESULTS: THN was characterized by a sudden onset of a purpuric halo surrounding a pre-existing nevus without any apparent trigger which occurred mainly in young females. Dermoscopically, the central nevus showed a black-brown, globular or homogeneous pattern, possibly interspersed with reddish, purple, or black structureless areas and comma-shaped vessels. The peripheric purpuric halo had two patterns: one with homogeneous reddish or purplish red areas, and another with an inner pale and outer homogeneous reddish or purplish red zone. The pathological findings showed an intradermal or compound nevus, dilated vessels, and extravasated erythrocytes, possibly accompanied by perivascular inflammatory infiltration and fibrin and hemosiderin deposits. CONCLUSION: THN is a benign lesion that usually requires no intervention other than follow-up observation. Dermoscopy is a useful non-invasive diagnostic tool, and biopsy can be avoided. The purpuric halo resolves spontaneously within two to four weeks with rare recurrence.

Preventing crossinfection during reflectance confocal microscopy, using a transparent film dressing.

Contamination and crossinfection are always a significant concern when using reflectance confocal microscopy in the clinic because the glass window and metal ring at the front of the probe must contact the skin and mucosal surfaces, and sterilization of the imaging probes is usually impossible. We describe use of a transparent, single-use film dressing to solve this problem.

Erythema papulatum centrifugum and new diagnostic criteria.

Erythema papulatum centrifugum (EPC), also known as erythema papulosa semicircularis recidivans (EPSR), is distinct from eczema and other well-described figurate erythemas characterised by annular erythematous lesions. We report 7 cases of EPC and propose new diagnostic criteria including the following: (i) EPC is characterised by single or multiple recurrent expanding annular or semi annular erythema with central regression, surrounded by tiny red papules; (ii) the lesions regularly relapse and resolve; (iii) the histopathologic feature shows superficial perivascular inflammation with or without mild inflammation around sweat glands in the mid dermis and (iv) patients lack other associated cutaneous or internal abnormalities.