Effect of reflex and mechanical decreases in skin perfusion on thermal- and agonist-induced eccrine sweating in humans.

In humans, skin blood flux (SkBF) and eccrine sweating are tightly coupled, suggesting common neural control and regulation. This study was designed to separate these two sympathetic nervous system end-organ responses via nonadrenergic SkBF-decreasing mechanical perturbations during heightened sudomotor drive. We induced sweating physiologically via whole body heat stress using a high-density tube-lined suit (protocol 1; 2 women, 4 men), and pharmacologically via forearm intradermal microdialysis of two steady-state doses of a cholinergic agonist, pilocarpine (protocol 2; 4 women, 3 men). During sweating induction, we decreased SkBF via three mechanical perturbations: arm and leg dependency to engage the cutaneous venoarteriolar response (CVAR), limb venous occlusion to engage the CVAR and decrease perfusion pressure, and limb arterial occlusion to cause ischemia. In protocol 1, heat stress increased arm cutaneous vascular conductance and forearm sweat rate (capacitance hygrometry). During heat stress, despite decreases in SkBF during each of the acute (3 min) mechanical perturbations, eccrine sweat rate was unaffected. During heat stress with extended (10 min) ischemia, sweat rate decreased. In protocol 2, both pilocarpine doses (ED50 and EMAX) increased SkBF and sweat rate. Each mechanical perturbation resulted in decreased SkBF but minimal changes in eccrine sweat rate. Taken together, these data indicate that a wide range of acute decreases in SkBF do not appear to proportionally decrease either physiologically- or pharmacologically induced eccrine sweating in peripheral skin. This preservation of evaporative cooling despite acutely decreased SkBF could have consequential impacts for heat storage and balance during changes in body posture, limb position, or blood flow restrictive conditions.

Osimertinib and Ramucirumab Induced Pyogenic Granulomas: A Possible Synergistic Effect of Dual Oncologic Therapy.

Pyogenic granulomas represent benign vascular tumors that can present on the skin and mucous membranes. Multiple etiologic agents have been implicated in the pathogenesis including several systemic medications. Two notable oncologic therapies, epidermal growth factor receptor inhibitors and vascular endothelial growth factor receptor inhibitors, have each been associated with drug-induced pyogenic granulomas. We report a novel case report of dual therapy, medication-induced pyogenic granulomas. This likely represents a synergistic relationship between an epidermal growth factor receptor inhibitor, osimertinib, and a vascular endothelial growth factor receptor inhibitor, ramucirumab.

An Atypical Presentation of Pityriasis Rosea Localized to the Extremities.

Pityriasis rosea (PR) is a benign, self-limiting, papulosquamous disorder characterized by the onset of a herald patch followed by an abrupt eruption of multiple salmon-colored papules and plaques on the trunk and proximal extremities. The individual lesions are often outlined by a collarette of scale and are distributed along the lines of cleavage. While many authors acknowledge an etiologic association with human herpesvirus 6 and human herpesvirus 7, thereby suggesting a viral exanthem, the exact cause remains unclear. While typically demonstrating a truncal predilection, this presentation may be absent in some patients who instead exhibit atypical features and distributions. Various clinical variants include papular, vesicular, purpuric, and eczematoid. The condition rarely manifests without truncal involvement and localized only to the distal extremities. We present a unique case report of a 65-year-old-male with biopsy-proven PR that was localized to his distal extremities with a clinical absence of truncal involvement.

Tumid Lupus Erythematosus: A Rare and Distinctive Variant of Cutaneous Lupus Erythematosus Masquerading as Urticarial Vasculitis.

Tumid lupus erythematosus (TLE) is a rare form of chronic cutaneous lupus that has triggered much debate regarding its clinical and histopathological features. It has been classically defined as annular erythematous, succulent, plaques involving the face and trunk that typically are devoid of any papulosquamous features such as scale and follicular plugging. These lesions are a clinical mimicker of other urticarial lesions such as urticarial vasculitis and lymphocytic infiltrate of Jessner. We report a case of TLE presenting in a 49-year-old Caucasian female whose initial clinical presentation was concerning for urticarial vasculitis due to presence of urticarial-like lesions present for approximately three months. Laboratory studies and histopathological correlations confirmed the diagnosis of TLE and the patient was successfully treated with topical corticosteroids.

Fungal Masquerader: A Case Report of Extramammary Paget's Disease Treated with Radiotherapy.

An 83-year-old Caucasian male presented with a pruritic erythematous patch to his right inguinal region, which he had contracted five months ago. After months of topical antifungal and steroid therapies, the patient was referred to dermatology due to a lack of lesion improvement. A 5.0 mm punch biopsy with immunohistochemical staining revealed the presence of pleomorphic nuclei with cytoplasm replete with mucin, suggestive of superficial extramammary Paget's disease (EMPD). As he was reluctant to undergo a surgical assessment, the patient underwent consultation and management with 30 sessions of superficial electron beam radiotherapy. A week after the completion of radiation therapy, the patient's skin exhibited minimal erythema with surrounding hyperpigmentation to the affected inguinal skin, suggesting clearance of the disease. This case highlights the importance of an accurate diagnosis in a timely manner as neoplastic cases have a metastatic risk with potentially devastating results.