Christopher J. Huerter

Manifestations of cutaneous diabetic microangiopathy.

The etiologies of a variety of skin conditions associated with diabetes have not been fully explained. One possible etiological factor is diabetic microangiopathy, which is known to affect the eyes and kidneys in patients with diabetes. There are many mechanisms by which diabetes may cause microangiopathy. These include excess sorbitol formation, increased glycation end products, oxidative damage, and protein kinase C overactivity. All of these processes occur in the skin, and the existence of a cutaneous diabetic microangiopathy has been well demonstrated. These microangiopathic changes are associated with abnormalities of skin perfusion. Because the skin plays a thermoregulatory role, there is significant capillary redundancy in normal skin. In diabetic patients, loss of capillaries is associated with a decrease in perfusion reserve. This lost reserve is demonstrable under stressed conditions, such as thermal stimulation. The associated failure of microvascular perfusion to meet the requirements of skin metabolism may result in diverse skin lesions in patients with diabetes.Many skin conditions peculiar to diabetes are fairly rare. Necrobiosis lipoidica diabeticorum (NLD) and diabetic bullae occur very infrequently as compared with diabetic retinopathy and nephropathy. Conversely, there is a correlation between diabetic microvascular disease and NLD. This correlation also exists with more common skin conditions, such as diabetic dermopathy. This relationship suggests that diabetic microangiopathy may contribute to these conditions even if it is not primarily causal.Clinically, the major significance of diabetic cutaneous microangiopathy is seen in skin ulceration which is very common and has a major impact on diabetic patients. Many factors contribute to the development of diabetic foot ulcers. Neuropathy, decreased large vessel perfusion, increased susceptibility to infection, and altered biomechanics all play a role, but there is no doubt that inadequate small blood vessel perfusion is a major cause of the inability to heal small wounds that eventually results in ulcer formation.The accessibility of skin capillaries makes cutaneous diabetic microangiopathy an attractive model for research on the evolution of microvascular disease in diabetic patients.

Purpura annularis telangiectodes of Majocchi: case report and review of the literature.

Background  Purpura annularis telangiectodes of Majocchi is an uncommon form of pigmented purpuric dermatosis which may present a therapeutic challenge. Given the rare nature of this condition, there is limited anecdotal information available regarding optimal therapy. Although pigmented purpuric dermatoses are generally innocuous, in some cases they may cause patients significant distress, and there is a need to exclude cutaneous T‐cell lymphoma.

Poorly Differentiated Squamous Cell Carcinoma Arising in Tattooed Skin

Introduction. Tattoos have increasingly become accepted by mainstream Western society. As a result, the incidence of tattoo-associated dermatoses is on the rise. The presence of a poorly differentiated squamous cell carcinoma in an old tattooed skin is of interest as it has not been previously documented. Case Presentation. A 79-year-old white homeless man of European descent presented to the dermatology clinic with a painless raised nodule on his left forearm arising in a tattooed area. A biopsy of the lesion revealed a poorly differentiated squamous cell carcinoma infiltrating into a tattoo. The lesion was completely excised and the patient remains disease-free one year later. Conclusion. All previous reports of squamous cell carcinomas arising in tattoos have been well-differentiated low-grade type or keratoacanthoma-type and are considered to be coincidental rather than related to any carcinogenic effect of the tattoo pigments. Tattoo-associated poorly differentiated invasive carcinoma appears to be extremely rare.

Do Melanoidins Induced by Topical 9% Dihydroxyacetone Sunless Tanning Spray Inhibit Vitamin D Production? A Pilot Study†

We report here preliminary pilot study data of the effect of sunless tanning spray with 9% [Correction added after online publication (August 24th, 2009): The concentration of Dihydroxyacetone used in the study was 9% and not 3% as previously stated] dihydroxyacetone (DHA) on 25‐hydroxyvitamin D [25(OH)D] serum levels in subjects exposed to controlled amounts of UV‐B radiation during April/May in Omaha, NE, 41°N latitude. We found that DHA‐induced melanoidins in skin act as a topical sunscreen attenuating the formation of 25(OH)D.

Light and laser treatment modalities for disseminated superficial actinic porokeratosis: a systematic review

Treatment of disseminated superficial actinic porokeratosis (DSAP) is poorly standardized. The present review seeks to comprehensively discuss the potential for laser and light modalities in the treatment of DSAP. A systematic review of light and laser treatment modalities was conducted to include 26 cases of patients with DSAP. Systematic review resulted in 14 articles to be included. Photodynamic therapy (PDT) overall was the least successful treatment modality, with clinical improvement seen in a minority of patients (MAL-PDT: N = 9 patients, 33.3% showed improvement; ALA-PDT: N = 3 patients, 0% improvement; hypericin-PDT: N = 2 patients, 0% improvement) after numerous post-procedural side effects of hyperpigmentation, inflammation, erythema, and discomfort. Overall, in the available reports, PDT demonstrates poor outcomes with greater incidence of side effects. The response rates of DSAP lesions treated with lasers were as follows: (Q-switched ruby lasers: N = 2, 100%; CO2 laser: N = 1, 100%; PDT and CO2 combination therapy: N = 2, 0–50%; erbium and neodymium YAG lasers: N = 2, 100%; fractional 1927-nm thulium fiber lasers: N = 2, 100%; Grenz rays: N = 1, 100%; and fractional photothermolysis: N = 2, 100%). The side effects of laser therapy were minimal and included mild erythema, slight hyperpigmentation, and moderate edema. Laser therapy is a promising treatment option for DSAP with an excellent side effect profile. However, higher power studies are required to determine optimal guidelines for laser treatment of DSAP.

A Man with an Umbilicated Papule of the Hand: What Is Your Diagnosis?

Introduction. Ecthyma contagiosum is a zoonotic disease caused by the parapoxvirus that causes “sore mouth” in sheep and goats and orf in human. Case Presentation. A 61-year-old sheep farmer presented with a painful non-pruritic lesion on the left hand that had been present for approximately 5 weeks. Physical examination demonstrated a 1 cm pearly, umbilicated papule with raised borders. A biopsy showed an asymmetrical nodule with parakeratotic crust and acanthosis with thin epidermal strands extending deeply in the underlying dermis. Marked edema, capillary proliferation and extensive lymphocytic infiltration was also present. One red intranuclear inclusion was identified in an epidermal keratinocyte. A diagnosis of human orf (ecthyma contagiosum) was made. Conclusion. Infected sheep and freshly vaccinated sheep or goats are the reservoir for human infection. After an incubation period of 3–7 days, parapoxvirus infections produce 1–3 painful lesions measuring 1-2 cm in diameter. The natural history of the disease is complete resolution and no treatment is indicated. Prevention of echthyma contagiosum in ruminants through vaccination is thought to be the best way to control infection.

Clinical Features and Treatment of Fibrous Histiocytomas of the Tongue: A Systematic Review

Introduction  Benign fibrous histiocytomas are common lesions of the skin that rarely affect the tongue. Such cases are available in the literature exclusively as case reports. Similarly, malignant fibrous histiocytoma, now classified as undifferentiated pleomorphic sarcoma, is exceedingly rare in the tongue and not fully understood. Objectives  This study systematically reviews the available literature discussing the clinical and pathological features of malignant and benign fibrous histiocytomas. Data Synthesis  A total of 20 cases were included in this review. Patient-level data were extracted from cases to include clinical presentation, workup, treatment, and outcome. Conclusion  Benign fibrous histiocytomas are consistent in clinical and histopathologic presentation. Surgical treatment provides excellent outcome, with no recurrence in all excised cases. Malignant tumors have a more aggressive clinical and pathological presentation. Surgical treatment with possible adjuvant radiotherapy resulted in recurrence in 40% of cases (follow-up of 24 months), and death due to disease in 47% of patients (follow-up of 19 months).

Clinical features and management of schwannoma affecting the upper and lower lips

Head and neck schwannomas comprise 25–40% of all schwannomas, with presentation on the lips as the rarest and most surgically complicated site for perioral tumors. A systematic literature review was conducted to include 21 cases of patients with schwannoma of the upper or lower lips. The majority of patients presented with a single, painless, well‐encapsulated nodule on the upper or lower lips. The nodules were consistently slow‐growing, with an average 29.3 months from symptom onset to clinical presentation. Most cases were complicated by profound cosmetic disfigurement as well as dysphagia, dysarthria, snoring, and/or sleep apnea. Overall, histological analysis was consistent with classic schwannoma, and all cases were treated via complete surgical excision, and for malignant tumors, additional therapy was utilized. All but four cases achieved full remission by final follow‐up. Recurrence rate for benign lip schwannomas was 5.3%, which is remarkably different from the standard recurrence rate of 8–24% for benign peripheral schwannomas. Additionally, the proportion of malignant tumors was greater for lip schwannomas than other schwannomas. Lip schwannomas demonstrate different characteristics than schwannomas from other locations on the body, and these remarkable differences highlight significant implications for clinical practice. Complete excision is the primary mode of treatment with overall excellent postoperative prognosis and rare instances of recurrence. Given the rarity of this tumor, this review of available cases serves to comprehensively describe clinical presentation and surgical treatment approaches to upper and lower lip schwannomas.

Systematic review of laser therapy in xanthelasma palpebrarum

Xanthelasma palpebrarum is a benign periorbital xanthoma with substantial cosmetic and psychosocial burden for patients. Treatment modalities should be considered based on efficacy as well as cosmetic outcome. Laser modalities in the treatment of xanthelasma palpebrarum have not been comprehensively reviewed and discussed. Accordingly, this study seeks to systematically and critically review the available literature discussing laser treatment of xanthelasma palpebrarum. PubMed was systematically reviewed for reports on laser therapy in the treatment of xanthelasma palpebrarum. A total of 21 studies were included in this review discussing laser treatment of xanthelasma palpebrarum. Laser types included carbon dioxide, yttrium aluminum garnet, pulsed dye, argon, and a 1450 nm diode laser. The carbon dioxide laser was the most commonly reported modality followed by yttrium aluminum garnet laser. All of the laser modalities offered moderate to excellent clearance rates with minimal side effect profiles. Further large scale studies comparing different laser modalities are required to determine the best laser modality. However, laser modalities as a whole offer a treatment option for xanthelasma palpebrarum, that is, cosmetically excellent with a reasonable side‐effect profile.

Clinical Features and Surgical Treatment of Schwannoma Affecting the Base of the Tongue: A Systematic Review

Introduction  Schwannomas of the head and neck account for 25–40% of all cases, with presentation at the base of the tongue as the most frequent site for intraoral tumors. Objectives  Here, a systematic review was conducted to include 15 cases of patients with schwannoma of the base of the tongue. Data Synthesis  Most patients presented with a single, painless, well-encapsulated nodule at the base of the tongue. These nodules were slow-growing, with an average of 13.3 months from onset to presentation. Most cases were accompanied by airway obstruction, indicated by symptoms of dysphagia, dysarthria, snoring, and sleep apnea. Overall, the histological studies were consistent with a benign schwannoma with a palisading Antoni A and Antoni B pattern without malignant changes in cell morphology. These tumors were treated via complete surgical excision, and all cases achieved full remission by final follow-up. Conclusion  Surgical removal is the primary mode of treatment with excellent postoperative prognosis and rare instances of recurrence. Given the rarity of this tumor, this review of available case studies serves to comprehensively describe clinical presentation and surgical treatment approaches to tongue base schwannoma.