A quantitative approach to histopathological dissection of elastin-related disorders using multiphoton microscopy.

BACKGROUND: Multiphoton microscopy (MPM) is a novel imaging technology that has recently become applicable for diagnostic purposes. The use of (near) infrared light in MPM allows for deep tissue imaging. In addition, this modality exploits the autofluorescent nature of extracellular matrix fibres within the skin. OBJECTIVES: To quantitate the structure and abundance of elastic fibres in human dermis in three dimensions utilizing autofluorescent signals generated by MPM for the objective examination of elastin-related skin disorders. METHODS: Cross-sections of skin samples from elastin-related disorders were analysed by MPM and correlated to histopathology. In situ visualization of elastic fibres by MPM was conducted by en face imaging of ex vivo skin samples through the intact epidermis. Image analysis software was used to quantify elastic fibres in three dimensions. RESULTS: Based on the MPM-detected elastin-specific autofluorescence, we developed the Dermal Elastin Morphology Index (DEMI), calculated as the ratio of elastic fibre surface area and volume. This enabled objective three-dimensional quantification of elastic fibres. Quantitative scoring of sun-damaged skin using DEMI correlated with qualitative histopathological grading of the severity of solar elastosis. Furthermore, this approach was applied to changes in elastic fibre architecture in other disorders, such as pseudoxanthoma elasticum (PXE), PXE-like syndrome, elastofibroma, focal dermal elastosis, anetoderma, mid-dermal elastolysis and striae distensae. We imaged elastic fibres in intact ex vivo skin imaged en face through the epidermis, indicating that this approach could be used in vivo. CONCLUSIONS: MPM has the potential for noninvasive in vivo visualization of elastic fibres in the dermis with near histological resolution. DEMI allows objective assessment of elastic fibres to support diagnosis and monitoring of disease progress or therapy of elastin-related skin disorders.

Pemphigoid gestationis occurring in a patient with HELLP syndrome.

A case of pemphigoid gestationis occurring in a 40 year old female who developed HELLP syndrome during her fourth pregnancy is reported. Seven days after emergency Caesarean section for pre-eclampsia, she developed a pruritic blistering eruption which clinically resembled pemphigoid gestationis. The diagnosis was supported by skin histology and immunofluorescence. She responded rapidly to oral corticosteroids, with no evidence of recurrence after 12 weeks of follow up. In the current case report, the previously unreported simultaneous occurrence of two uncommon conditions is described.

Topical tretinoin improves the appearance of photo damaged skin.

A multicentre clinical trial has been conducted to assess the efficacy and safety of tretinoin 0.05% cream (Retin-A) in the treatment of photo-damaged Australian skin. Subjects with cutaneous facial photodamage were randomised to treatment with tretinoin (62) or vehicle (63) cream. After an initial two week run-in, all subjects applied the cream to the face, neck and left forearm/hand, once nightly for 24 weeks. Changes in clinical signs of photodamage and parameters of cutaneous irritation were assessed by investigators using a 7 point scale, whilst changes in signs of photodamage were rated by subjects using a 5 point scale. Changes in skin biopsies and silicone skin surface replicas were also assessed. Significant improvements in skin wrinkles, mottled hyperpigmentation, laxity, lentigines and roughness of tretinoin treated subjects were noted by investigators. Subjects receiving tretinoin noted significant improvements in skin wrinkles, tightness, colour and pores. Improvement in overall severity of photodamage was significantly greater for tretinoin treated subjects and was progressive over the study period. Histological findings included a significant increase in mean epidermal thickness. Significant topographical changes were not detected in skin surface replica sets. Cutaneous irritation, the most common side effect, was usually mild and transient. We conclude that tretinoin 0.05% cream significantly improved the appearance of photo-damaged skin.

Subcutaneous fat necrosis following traumatic pancreatitis.

A 25 year old female who developed subcutaneous fat necrosis and polyarthritis secondary to post-traumatic pancreatitis is reported. This is a well documented but uncommon phenomenom, affecting less than 1% of patients with pancreatic disease.