Painless nodules on legs.

The location of the nodules and the patient's history were important diagnostic clues. The punch biopsy confirmed our suspicions.

Reactive Epidermal Hyperplasia and Angiogenesis of the Rear (REAR): A Proposed Unifying Name for Senile Gluteal Dermatosis and Prurigiform Angiomatosis.

Senile gluteal dermatosis (SGD) is a common but seldom recognized condition. It is characterized clinically by unilateral or bilateral hyperkeratotic, lichenified plaques on the gluteal area, being attributed to prolonged sitting, particularly in the elderly. SGD also encompasses the recently proposed entity of prurigiform angiomatosis. Histologically, there are features of lichenification, such as epidermal hyperplasia and a preserved granular layer, with prominent dermal angioproliferation. We report 4 cases of this condition as well as novel findings of variably increased mast cells and superficial lymphatic vessels in addition to the proliferation of dermal blood vessels. We propose a unifying name for Reactive Epidermal hyperplasia and Angiogenesis of the Rear (REAR) to encapsulate the characteristic clinical and histological features of this distinct entity.

Morphoea following COVID-19 vaccination.

We present a case of generalized morphoea developing after recent COVID-19 mRNA vaccination and suggest the plausible pathomechanisms.

Keratin-Alginate Sponges Support Healing of Partial-Thickness Burns.

Deep partial-thickness burns damage most of the dermis and can cause severe pain, scarring, and mortality if left untreated. This study serves to evaluate the effectiveness of crosslinked keratin-alginate composite sponges as dermal substitutes for deep partial-thickness burns. Crosslinked keratin-alginate sponges were tested for the ability to support human dermal fibroblasts in vitro and to support the closure and healing of partial-thickness burn wounds in Sus scrofa pigs. Keratin-alginate composite sponges supported the enhanced proliferation of human dermal fibroblasts compared to alginate-only sponges and exhibited decreased contraction in vitro when compared to keratin only sponges. As dermal substitutes in vivo, the sponges supported the expression of keratin 14, alpha-smooth muscle actin, and collagen IV within wound sites, comparable to collagen sponges. Keratin-alginate composite sponges supported the regeneration of basement membranes in the wounds more than in collagen-treated wounds and non-grafted controls, suggesting the subsequent development of pathological scar tissues may be minimized. Results from this study indicate that crosslinked keratin-alginate sponges are suitable alternative dermal substitutes for clinical applications in wound healing and skin regeneration.

Fibroblastic Rheumatism Versus Variant Disease of Multinucleate Cell Angiohistiocytoma.

We report an unusual case of a 49-year-old woman who presented with persistent papulonodules over bilateral fingers and inframammary region in conjunction with features of connective tissue disease including symmetrical polyarthritis and Raynaud phenomenon. Skin biopsy showed an upper-to-mid dermal proliferation of bland spindled cells with thickened collagen bundles and occasional multinucleated giant cells. Dermal blood vessels were only marginally increased. On immunohistochemistry, both the spindled cells and multinucleated giant cells stained negatively for smooth muscle actin. Some of the spindled cells stained positively with CD68 and CD163, whereas the multinucleated giant cells stained negatively for both stains. Elastic fibers were absent on elastic Van Gieson. The clinical and histopathologic features raise a diagnostic dilemma between fibroblastic rheumatism and multinucleate cell angiohistiocytoma. The patient responded well to cyclosporine and methotrexate therapy, with gradual improvement of the finger nodules.

A challenging diagnosis of MPO-C-ANCA EGPA.

Eosinophilic granulomatosis with polyangiitis (EGPA) is a multisystemic small-vessel vasculitic disease that can present with positive MPO-P-ANCA (myeloperoxidase-perinuclear-anti-neutrophil cytoplasmic antibody). It is a rare condition that is difficult to diagnose. We present the case of a 64-year-old man with late-onset adult asthma and treated nasopharyngeal carcinoma who initially presented to us with proximal myopathy. Thereafter, he developed a constellation of fleeting symptoms which included rhinosinusitis, mononeuritis multiplex, skin vasculitis and arthritis. Blood investigations showed that he had eosinophilia, and skin biopsy demonstrated dermal vasculitis with eosinophils. He was found to be MPO-C-ANCA positive, and although initially thought to have granulomatosis with polyangiitis, the diagnosis was later revised to EGPA. This case highlights the diagnostic challenges with atypical presentations of EGPA and also presents a rare case of positive MPO-C-ANCA that has never been described in EGPA before.

Reflectance confocal microscopy is a useful non-invasive tool in the in vivo diagnosis of pigmented basal cell carcinoma in Asians.

BACKGROUND: The clinical differentiation between pigmented basal cell carcinoma (BCC) and other benign pigmented skin lesions can be challenging even with an additional dermoscopic evaluation, especially if the lesion is small. In vivo reflectance confocal microscopy (RCM) is an emerging, non-invasive imaging tool that allows near-microscopic evaluation of skin lesions. The features of RCM for pigmented BCC and seborrhoeic keratosis have previously been described. However, the use of RCM to differentiate between these clinically and dermoscopically challenging pigmented skin lesions among Asians has not yet been demonstrated. OBJECTIVES: We aimed to evaluate the usefulness of non-invasive RCM to differentiate between clinically and dermoscopically challenging pigmented skin lesions among Asians in a series of 11 lesions. METHODS: Nine patients with 11 clinically and dermoscopically difficult to distinguish pigmented skin lesions were evaluated by RCM to differentiate between pigmented BCC and benign lesions. In all cases, a histological confirmation of the RCM diagnosis was obtained. RESULTS: The clinical or dermoscopical characteristics were non-specific in all 10 cases. RCM detected features of pigmented BCC in nine patients and seborrhoeic keratosis in one patient. These were all confirmed by histological examination. CONCLUSIONS: This case series shows the value of non-invasive in vivo RCM imaging in the differentiation of malignant and benign pigmented lesions. Early diagnosis of small, pigmented BCC allows earlier excision with better prognosis. Future biopsies of benign lesions in cosmetic areas could also be avoided.