Todd, Austin W.

ABSTRACTBackgroundIntercellular IgG4 deposition is variably present on DIF in patients with pemphigus. Whether this feature has clinical, serologic, or histopathologic correlates was unknown.MethodsWe identified 34 patients with pemphigus who had 55 DIF specimens reported to show intercellular IgG, IgG4, and/or C3 deposition (8/22/2017–11/30/2023). Patients and biopsies were stratified by intercellular IgG4 status. Clinical and serologic data were extracted from electronic records, and corresponding biopsy slides were reviewed for histopathologic findings.ResultsAmong the 34 patients with pemphigus, patients with positive IgG4 were significantly more likely to have detectable serum anti‐desmoglein 1/3 antibodies by ELISA (p = 0.014 and p = 0.030, respectively). Paraneoplastic pemphigus (PNP) was more frequent in the IgG4‐negative group (p = 0.037), particularly among patients with ocular involvement. Of 55 DIF biopsy specimens meeting inclusion criteria, 52 (94.5%) had intercellular IgG deposition and 42 (76.4%) had intercellular IgG4 on DIF. Compared to IgG4‐negative specimens, IgG4‐positive specimens were significantly more likely to represent a vesiculobullous lesion (p = 0.024), to be derived from the trunk (p = 0.047), to show histologic acantholysis (p = 0.019) and to lack lichenoid inflammation (p = 0.0004).ConclusionFor pemphigus, DIF IgG4 status correlated with ocular involvement, the clinical morphology selected for biopsy, the likelihood of detecting circulating desmoglein antibodies, the presence of specific histopathologic features such as acantholysis and lichenoid inflammation, and the likelihood of having a final diagnosis of PNP. Further studies are needed to determine whether the presence of tissue‐bound intercellular IgG4 antibodies correlates with particular disease variants or lesion‐specific characteristics.

ABSTRACTBackgroundHidradenitis suppurativa (HS) is a chronic inflammatory condition. While obesity is linked to increased HS severity in adults, data on its impact in pediatric HS remain limited. This study investigates the relationships between obesity, HS severity, HS‐related comorbidities, and therapeutic management in pediatric patients.MethodsThis is a retrospective cohort analysis on patients diagnosed with HS before 18 years of age. Data were collected on disease severity, comorbidity development, and treatments. Trends were compared between HS patients with and without obesity and with healthy controls for comorbidity development.ResultsThere was no difference in disease severity using Hurley staging between patients with and without obesity (p = 0.679). Patients with obesity were more likely to be prescribed biologics (p = 0.012), but not other treatments. The risk of developing dyslipidemia, anxiety, depression, and thyroid disease was elevated in pediatric HS patients, even after controlling for BMI (p < 0.001).ConclusionsIn this study, obesity was not associated with HS disease severity in children. However, children with obesity were more likely to be prescribed biologics. HS may independently increase the risk of dyslipidemia, anxiety, depression, and thyroid disease.

Background: Optimum timing of surgery for severe primary mitral regurgitation (MR) particularly in the absence of significant symptoms or echo evidence of LV impairment remains unclear. Other modalities of assessment include cardiopulmonary exercise testing (CPET) and novel echo measurements, such as LV global longitudinal strain (LVGLS). We sought to evaluate whether pre-op CPET or LVGLS are associated with survival after surgery. Methods: We identified consecutive patients who had surgery for severe primary MR between 2007 and 2017 and had pre-op CPET. Clinical and mortality data were collected from chart review and our institutional database. LVGLS was retrospectively collected by a single person blinded to patient outcomes. Primary outcome was post surgery all cause death, and we used univariable analysis to identify variables associated with all cause death. Results: We included 176 patients with median age 63 (IQR 51, 71) years, 63 patients (35.8%) were female and 31 patients (14.8%) had a history of atrial fibrillation. 165 patients (93.8%) had mitral repair, 18 (10.2%) had concomitant CABG, 22 (12.5%) had concomitant ablation procedure and 14 (8.0%) had concomitant tricuspid procedure. 114 patients (64.8%) were in NYHA Class I and 56 (31.8%) were in NYHA Class II. There was no operative mortality. Median % predicted peak VO2 (ppVO2) was 89 (74, 101), median ventilatory equivalent of carbon dioxide (VE/VCO2) was 28.0 (25.7, 31.0) l/min/l/min and median respiratory exchange ratio was 1.2 (1.1, 1.2). 73 patients (41.5%) had abnormal CPET (defined as ppVO2<85%). Median LVEF was 65 (60, 68) %, median LVESD was 35 (32, 38) mm and median LVGLS was 18.5 (16.6, 20.3) %. 45 patients (25.9%) had abnormal LVEF (defined as ≤ 60%), 11 patients (6.7%) had abnormal LVESD (defined as ≥45mm) and 35 patients (20.8%) had abnormal LVGLS (defined as <16%). At a median follow up of 10.2 (6.8, 13.2) years, there were 19 (10.8%) deaths. In the univariate analysis, age at surgery (HR 1.12, p<0.001), LVESD (HR 1.11, p=0.009), LVGLS (HR 1.11, p=0.013) and VE/VCO2 (HR 1.08, p=0.044) were associated with all cause mortality. Conclusion: A significant proportion of patients with no or mild symptoms exhibit echocardiographic evidence of LV impairment when having surgery for severe primary MR. CPET parameters such as VE/VCO2 and novel echocardiographic measurements such as LVGLS may predict risk of long term mortality and potentially inform timing of surgery in these patients.

Background: Maculopapular cutaneous mastocytosis (MPCM) is a rare disorder characterized by a pathologic accumulation of mast cells in the skin, which may or may not be accompanied by systemic mastocytosis. Diagnosis of MPCM on skin biopsy can be challenging because the findings may be subtle. Although mast cell density in MPCM has been reported, data informing a proposed cutoff for diagnosis and diagnostic criteria are limited. Methods: We identified adult patients diagnosed with MPCM and urticarial tissue reaction/chronic urticaria on skin biopsy and compared the mast cell and eosinophil counts per 1 mm2 in 10 cases each of MPCM, chronic urticaria, and normal skin from routine biopsies. All slides were stained with CD117, and CD117-positive mast cells were counted per 1 mm2 using digital microscopy. Eosinophils were counted on hematoxylin and eosin-stained slides per 1 mm2 using digital microscopy. Results: The median number of mast cells per 1 mm2 was significantly higher in MPCM than in cases of urticaria and normal skin/control tissue (177.3 vs. 26.8 vs. 47.8 mast cell per mm2, respectively; P ≤ 0.001). The calculated “cut point” for mastocytosis versus chronic urticaria and normal skin was 66 mast cells per 1 mm2, whereas the value for controls versus urticaria was 37 mast cells per 1 mm2. Eosinophils had similar density in MPCM and urticaria, and their presence was significant in the differentiation of MPCM and urticaria from normal tissue. Conclusions: This study adds to the literature by providing objective mast cell density data to distinguish challenging cases of cutaneous mastocytosis from urticarial reactions and normal skin. Future studies could explore the development of computer-aided estimations of cellular density with more extensive comparison with other inflammatory conditions to translate our findings more readily into clinical practice.

BACKGROUND The use of Mohs micrographic surgery with melanocytic immunostains (MMS-I) for cutaneous melanoma is increasing. OBJECTIVE To assess local recurrence, melanoma-specific death rates in patients with invasive melanoma treated with MMS-I. MATERIALS AND METHODS A single-center retrospective review of patients with invasive melanoma treated with MMS-I from January 2008 to December 2018. RESULTS Three hundred fifty-two patients (359 melanomas) were included. The median age was 71 years; most patients were male (252%; 71.6%). Most tumors were T1a/b (341, 95%), H/N (322; 89.7%), and lentigo maligna subtype (281, 78.3%). At a median follow-up of 4.3 years, local recurrence rates were 1.4% (5) and 0.9% (3) among all-stage and T1a/b tumors, respectively. There were 3 melanoma-related deaths (0.9%). CONCLUSION MMS-I is associated with <1% risk of local recurrence and disease-specific mortality for T1a/b melanomas.

Abstract Background Perianal draining tunnels in hidradenitis suppurativa (HS) and perianal fistulizing inflammatory bowel disease (IBD) present diagnostic and management dilemmas. Methods We conducted a retrospective chart review of patients with perianal disease evaluated at Mayo Clinic from January 1, 1998, through July 31, 2021. Patients' demographic and clinical data were extracted, and 28 clinical features were collected. After experimenting with several machine learning techniques, random forests were used to select the 15 most important clinical features to construct the diagnostic prediction model to distinguish perianal HS from fistulizing perianal IBD. Results A total of 263 patients were included (98 with HS, 100 with IBD, and 65 with both IBD and HS). Patients with HS had a higher mean body mass index, a higher smoking rate, and more commonly showed cutaneous manifestations of tunnels and comedones, while fistulas, abscesses, induration, anal tags, ulcers, and anal fissures were more common in patients with IBD. In addition to having lesions in the perianal area, patients with IBD often had lesions in the buttocks and perineum, while those with HS had additional lesions in the axillae and groin. Among the statistically significant features, the 15 most important were identified by random forest: fistula , tunnel , digestive symptom , knife‐cut ulcer , perineum , body mass index , age , axilla , abscess , tags , smoking , groin , genital cutaneous edema , erythema , and bilateral/unilateral . Conclusions The results of this study may help differentiate perianal lesions, especially perineal HS and fistulizing perineal IBD, and provide promise for a better therapeutic outcome.

Abstract Background Immune checkpoint inhibitors (ICIs) have transformed cancer treatment by targeting immune checkpoints such as PD‐1, PDL‐1, and CTLA‐4, but concerns about severe immune‐related adverse events persist. The scarcity of literature on dermatologic implications, especially severe reactions such as Stevens‐Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), highlights the urgent need for investigation. Objective Our systematic review aims to address the gap in relevant literature by extensively examining the epidemiologic risk factors and management of SJS/TEN‐like illnesses in ICI‐treated patients to provide insights for risk assessment and clinical care. Method s We identified 158 case reports that detailed the incidence of SJS/TEN in patients being treated with ICIs, examining demographic patterns, type of malignancy, clinical characteristics, and treatments linked to onset. We assessed mortality rates, risk elements, and the effectiveness of interventions to help guide clinical care. Results Analysis of 158 case reports revealed that SJS/TEN in ICI users is typically seen on average at the age of 63 and is more common in males. PD1 inhibitors such as nivolumab and pembrolizumab are often associated with various mucocutaneous patterns and significant risks with ICI use, especially TEN, which is linked to high morbidity and mortality rates. Limitations Our study notes limitations due to the inclusion of case reports or case series, such as potential publication and reporting biases, leading to skewed findings. Additionally, because of the heterogeneous reporting standards, the retrospective nature limits phenotypic precision, control for confounding variables, and data completeness. Conclusion Our study provides valuable insights into the epidemiology, clinical features, management strategies, and outcomes of ICI‐induced SJS/TEN, underscoring the importance of vigilant monitoring and personalized risk assessment in oncology practice. Continued research efforts are essential to optimize patient outcomes and enhance the safety profile of ICIs in cancer therapy.

Background: Following transition to digital pathology for primary diagnosis at our institution, dermatology residents have reduced exposure to light microscopy. This study compares resident competency with light microscopy versus digital pathology following practice changes. Methods: Twenty-one dermatology residents were administered a dermatopathology examination composed of 32 diagnoses evaluated using digital slides and 32 with light microscopy. Case difficulty was graded and balanced between modalities. Diagnostic accuracy was measured using the number of correct diagnoses for each modality. Participants were surveyed regarding their experience and preferences. Results: Diagnostic accuracy was higher with digital pathology than light microscopy (22/32 vs. 18/32, P < 0.001). Diagnostic accuracy with digital pathology increased with years of training, but accuracy with light microscopy did not. Residents with previous light microscopy experience achieved an average score of 19/32 on glass, as compared with 10/32 for those without experience (P = 0.039). Digital pathology was preferred over light microscopy (18/21, 85.7%). Conclusions: Trainees had better diagnostic proficiency with digital pathology and preferred this modality. Most practices at this time continue to use light microscopy. Therefore, we need to maintain proficiency in microscopy during training while concurrently preparing trainees for a digital future.