Davis, Mark D.P.

BACKGROUND: Lipodermatosclerosis (LDS) is a type of sclerosing panniculitis that predominantly involves the lower extremities and is characterized by erythema, hemosiderin pigmentation, and sclerotic skin lesions. LDS is a common reason for specialty consultations across clinical settings, including dermatology, vascular medicine, and occasionally the emergency department or internal medicine services. METHODS: To further evaluate the prevalence of venous hypertension in patients with LDS at the authors’ institution, they retrospectively reviewed the findings of lower extremity Doppler ultrasonography with or without segmental pressure (ie, venous ultrasonography) performed for adult patients with biopsy-confirmed LDS who were treated at the Clinic from January 1, 2000, through September 30, 2022. RESULTS: A total of 430 patients were included in the study. Venous ultrasonography findings were abnormal for 327 (76.0%) patients, whereas the other 103 (23.9%) patients had normal findings. Venous hemodynamics studies, including air plethysmography and continuous-wave Doppler ultrasonography, were performed for 33 patients with normal venous ultrasonography findings. Of these patients, 7 had mild valvular incompetence, 12 had abnormal calf muscle pump function, and 2 had pulsatility (backflow in the peripheral vein with elevated right atrial pressure) evident on continuous-wave Doppler ultrasonography. CONCLUSIONS: Overall, the findings extend previous observations that venous abnormalities are commonly present in patients with LDS and may contribute to its pathogenesis. However, a few patients with LDS have normal venous hemodynamics, which suggests that other factors also contribute to LDS pathogenesis.

Abstract: Background: Extended patch testing beyond the standard series is commonly performed in patients with allergic contact dermatitis. This broader testing allows for more precise and complete allergen identification, ultimately leading to improved clinical outcomes. Objective: To report the Mayo Clinic Contact Dermatitis Group (MCCDG) patch testing results using a custom extended series from 2010 to 2023. Methods: A retrospective review of patch testing results using the MCCDG extended standard series at the Mayo Clinic was conducted. Data from 2010 to 2023 were analyzed. Results: Patch testing with the extended standard series was performed in 3,767 unique patients, with a total of 3834 extended standard patch tests administered (81.8% in women, 18.2% in men). The top 5 allergens eliciting positive reactions were gold (I) sodium thiosulfate (10.4%), benzisothiazolinone (10.4%), carmine (9.4%), thimerosal (9.3%), and hydroperoxides of linalool (8.8%). Conclusions: The extended standard series expands the diagnostic scope for patients in whom the standard series incompletely identifies relevant allergens. Preservatives and fragrances remain among the most common sensitizers, emphasizing the need for ongoing allergen surveillance, periodic review, and updates to patch test series to enhance diagnostic accuracy and patient care.

ABSTRACTBackgroundDrug‐induced hypersensitivity syndrome (DiHS), or drug reaction with eosinophilia and systemic symptoms (DRESS), is a delayed and severe immune response to certain medications. We investigated vancomycin‐induced DiHS/DRESS, notable for frequent and severe organ involvement, to describe its specific histopathology and the correlations between histopathologic and clinical findings.MethodsA retrospective review was conducted to identify patients between 2006 and 2022 who received vancomycin, had archived skin biopsy specimens, and were scored as having probable or definite DiHS/DRESS. Clinical features were retrospectively collected, and biopsy specimens were reviewed by a board‐certified dermatopathologist. A subset of histopathologic and clinical features was analyzed for statistical correlation.ResultsTwenty‐three patients met the inclusion criteria. Most biopsy specimens (87%) showed an eczematous reaction pattern; 17 (74%) showed a secondary reaction pattern. Spongiosis (87%) and neutrophilic infiltration (91%) were common epidermal characteristics. The dermal inflammatory infiltrate was frequently superficial (87%) and consistently included plasma cells (96%). Eosinophils were present in the dermis in 70% of cases. Parakeratosis negatively correlated with liver involvement and positively correlated with desquamative rash. Epidermal lymphocytes were negatively correlated with the RegiSCAR score.ConclusionsVancomycin‐associated DiHS/DRESS histopathology was characterized by a frequent eczematous reaction pattern, multiple coexisting reaction patterns, and epidermal neutrophilic infiltration.

Abstract: Background: It is generally recommended that patients not be on immunosuppressive medications for patch testing, as these medications may suppress delayed-type hypersensitivity and lead to false negative results. There is a paucity of literature describing organ transplant recipients who underwent patch testing. Objective: The aim of this study is to examine patch testing results in solid organ transplant recipients over a 13-year period at our institution. Methods: We performed a retrospective analysis of patch test data from adult transplant recipients at our institution. Transplant patients who underwent patch testing were identified from a clinical patch test database, and a chart review was conducted. Results: Eighteen patients were included in the study. Patients had received kidney, liver, or heart transplants. Seven patients (38.9%) had at least one positive reaction. The highest reaction rates were seen with methylisothiazolinone (12.5%), methyldibromo glutaronitrile (12.5%), and benzalkonium chloride (10.0%). Limitations included small sample size, data from a tertiary referral center, and retrospective analysis. Conclusions: Liver and kidney transplant recipients displayed allergic reactions during patch testing. Patients may benefit from patch testing even if receiving immunosuppressive therapy, but some reactions may be falsely negative because of immunosuppression.

Erythromelalgia is a rare disorder characterized by episodic burning pain with redness and warmth of the extremities. Topical and systemic medications are the mainstay of management. We reviewed the published evidence for using procedural interventions to manage erythromelalgia, including their proposed mechanism of action and possible adverse effects, and included information in this review on epidural infusion, sympathetic ganglion block, sympathectomy, pulsed radiofrequency, spinal cord stimulation, dorsal root ganglion stimulation, brain stimulation, transcranial magnetic stimulation, and botulinum toxin injections. Both successful and unsuccessful outcomes have been reported. Although these procedural interventions extend the therapeutic options for erythromelalgia, the evidence for their use is limited. Case reports and small case series comprise most of the evidence. Based on our review, a multidisciplinary approach to management may be needed for patients with erythromelalgia.

AbstractHistiocytoid Sweet syndrome (H‐SS) is a histopathological variant of Sweet syndrome (SS) defined by cutaneous infiltration of immature myeloid cells morphologically resembling histiocytes. The association of H‐SS with underlying malignancy, particularly myelodysplastic syndromes, is well‐established. Myelodysplasia cutis (MDS‐cutis) has been proposed to describe cases historically diagnosed as H‐SS but characterized by shared clonality of the myeloid infiltrate in skin and bone marrow. Therefore, identifying patients who might have MDS‐cutis is critical for the management of the associated hematologic malignancy. VEXAS syndrome, an adult‐onset autoinflammatory disease, should also be included in the histopathologic differential diagnosis of H‐SS, as it shares clinical and pathologic features with MDS‐cutis. Through the presentation of two cases, we aim to highlight the defining features and key clinical implications of MDS‐cutis and VEXAS syndrome.