Distal Biopsies Research Articles

Vascular and nerve biomarkers in thigh skin biopsies differentiate painful from painless diabetic peripheral neuropathy.

Identifying distinct mechanisms and biomarkers for painful diabetic peripheral neuropathy (DPN) is required for advancing the treatment of this major global unmet clinical need. We previously provided evidence in calf skin biopsies that disproportion between reduced sensory small nerve fibers and increased blood vessels may distinguish painful from non-painful DPN. We proposed that overexposure of the reduced nerve fibers in DPN to increased hypoxemia-induced vasculature and related algogenic factors, e.g., nerve growth factor (NGF), leads to neuropathic pain. To further investigate this proposed mechanism, we have now studied more proximal thigh skin biopsies, to see if the same disproportion between increased vasculature and decreased nerve fibers generally differentiates painful DPN from painless DPN. A total of 28 subjects with type 2 diabetes (T2DM) and 13 healthy volunteers (HV) underwent detailed clinical and neurophysiological assessments, based on the neuropathy composite score of the lower limbs [NIS(LL)] plus 7 tests. T2DM subjects were subsequently divided into three groups: painful DPN (n = 15), painless DPN (n = 7), and no DPN (n = 6). All subjects underwent skin punch biopsy from the upper lateral thigh 20 cm below the anterior iliac spine. Skin biopsies showed decreased PGP 9.5-positive intraepidermal nerve fiber (IENF) density in both painful DPN (p < 0.0001) and painless DPN (p = 0.001). Vascular marker von Willebrand Factor (vWF) density was markedly increased in painful DPN vs. other groups, including painless DPN (p = 0.01). There was a resulting significant decrease in the ratio of intraepidermal nerve fiber density to vasculature and PGP9.5 to vWF, in painful DPN vs. painless DPN (p = 0.05). These results were similar in pattern to those observed in these HV and T2DM groups previously in distal calf biopsies; however, the increase in vWF was much higher and nerve fiber density much lower in the calf than thigh for painful DPN. Thigh skin vWF density was significantly correlated with several metabolic (waist/hip ratio, HbA1c), clinical (e.g., pain score), and neurophysiological measures. This study supports our proposal that increased dermal vasculature, and its disproportionate ratio to reduced nociceptors, may help differentiate painful DPN from painless DPN. This disproportion is greater in the distal calf than the proximal thigh skin; hence, neuropathic pain in DPN is length-dependent and first localized to the distal lower limbs, mainly feet.

A - 115 Cognitive Predictors of Phosphorylated Skin Nerve α-Synuclein Deposition in Patients with Suspected Synucleinopathy

Abstract Objective Synucleinopathies are a group of neurodegenerative diseases caused by abnormal α-Synuclein aggregates and characterized by motor, autonomic, and cognitive changes, including Parkinson’s disease, Lewy Body disease, and Multiple System Atrophy. Due to variability in presentation, clinical phenotyping is challenging for diagnosis and treatment planning. Phosphorylated α-Synuclein (P-syn) detected in nerve fibers using skin biopsy shows promise in clinical phenotyping of synucleinopathies. However, cognitive predictors of P-syn deposition in synucleinopathies have not been fully explored. This study aimed to examine the utility of cognitive testing in predicting P-syn deposition in a clinical sample. Method A chart review of 52 older adults (Mean age = 72.8 years) referred to an outpatient neurology clinic for a diagnostic dementia workup was conducted. Clinical variables were collected, including skin biopsy (Syn-One) and cognitive test scores (Short Test of Mental Status [STMS]). P-syn was detected in 22 patients (42%) and at 68%, 41%, and 55% of central (neck) and distal (thigh and calf) biopsy sites, respectively. Results Overall cognition (STMS Total) did not significantly differ between patients with (Mean = 30.5) and without (Mean = 29.6) P-syn (p = 0.51). Within the P-syn positive group, STMS Registration-Trials and Calculation scores significantly predicted distally deposited P-syn (F(1,18) = 7.54, p = 0.01). This relationship was more pronounced in the thigh compared to the calf biopsy sites. Conclusion STMS Registration-Trials (immediate recall) and Calculation scores were significantly related to distally deposited P-syn. These findings highlight the importance of how cognitive test performance can potentially impact clinical phenotyping in synucleinopathies. Future research will examine the relationship between cognition, clinical features, and other neurodegenerative disease biomarkers.

Variation in proliferative and cell cycle markers in Barrett's esophagus in relation to circumferential and axial location in the esophagus.

Adenocarcinoma in Barrett's esophagus (BE) occurs more frequently between 12 and 3 o'clock at the gastroesophageal junction (GEJ). BE patients were prospectively recruited from December 2013 to July 2016. Expression of p53, Ki-67, cyclin-D1, COX-2 and p21 was assessed in quadrantic biopsies from the proximal and distal margins of the BE segments. Cell cycle marker association with current or subsequent dysplasia or adenocarcinoma was examined. 110 patients: median age 64 (IQR, 56-71) years; median BE segment length C4M6; and a median follow-up of 4.7 (IQR, 3.6-5.7) years. In total 13 (11.8%) had evidence of dysplasia or neoplasia (2.7% indefinite for dysplasia, 5.5% low grade, 1.8% high grade and 1.8% adenocarcinoma) at index endoscopy. Six (7%) developed dysplasia or neoplasia (1 low grade, 2 high grade and 3 adenocarcinoma) during follow-up. Ki-67 expression was highest at 3 o'clock, and overall was 49.6% higher in the 12-6 o'clock position compared to 6-12 o'clock [odds ratio (OR), 1.42 (95% confidence interval (CI), 1.00-2.12)]. A similar pattern was found with p21 [1.82 (1.00-3.47)]. There was increased expression of several markers in distal BE biopsies; cyclin-D1 [1.74 (1.29-2.34)]; Cyclo-oxygenase 2 [2.03 (1.48-2.78]) and p21 [2.06 (1.16-3.68)]. Expression of Ki-67 was lower in distal compared to proximal biopsies [0.58 (0.43-0.78)]. P53 expression had high specificity (93.8%) for subsequent low-grade dysplasia, high-grade dysplasia or adenocarcinoma. Increased cellular proliferation was seen at 12-6 o'clock at the GEJ. Cell-cycle marker expression was increased at the GEJ compared to the proximal BE segment. These findings mirror reflux esophagitis and suggest ongoing reflux contributes to the progression of dysplasia and malignancy in BE.

Anastomotic leak in colorectal cancer surgery: Contribution of gut microbiota and prediction approaches.

To monitor prospectively the occurrence of colorectal anastomotic leakage (CAL) in patients with colon cancer undergoing resectional surgery, characterizing the microbiota in both faeces and mucosal biopsies of anastomosis. In a second stage, we investigated the ability to predict CAL using machine learning models based on clinical data and microbiota composition. A total of 111 patients were included, from whom a faecal sample was obtained, as well as biopsy samples from proximal and distal sites in the healthy margins of the tumour piece. The microorganisms present in the samples were investigated using microbial culture and 16S rDNA massive sequencing. Collagenase and protease production was determined, as well as the presence of genes responsible for expressing enzymes with these activities. Machine learning analyses were developed using clinical and microbiological data. The incidence of CAL was 9.0%, and CAL was associated with collagenase/protease-producing Enterococcus. Significant differences were found in the microbiota composition of proximal and distal biopsy samples, but not in faecal samples, among patients who developed CAL. Clinical predictors of CAL were 5-day C-reactive protein and heart disease, whereas 3-day C-reactive protein and diabetes were negative predictors. Biopsy samples from surgical margins, rather than faecal samples, are the most appropriate samples for exploring the contribution of the intestinal microbiota to CAL. Enterococci are only enriched in the anastomosis after surgery, and their collagenases and proteases are involved in the degradation of the anastomotic scar.

Decaying kidney function during cirrhosis correlates with remodeling of distal colon aldosterone target gene expression.

Liver cirrhosis is associated to circulatory abnormalities leading to hypovolemia and stimulation of the renin-angiotensin-aldosterone system (RAAS). Advanced stages of the disease cause renal failure, impairing K+ and Na+ homeostasis. It has been proposed that the distal colon undergoes functional remodeling during renal failure, in particular by aldosterone-driven increased K+ excretion. In this study, we compared the transcriptional response of aldosterone target genes in the rat distal colon under two models of increased circulating aldosterone (one with concomitant RAAS activation) and in a model of secondary hyperaldosteronism induced by cirrhosis. The expression of a subset of these genes was also tested in distal colon biopsies from control subjects or patients with cirrhosis with varying levels of disease progression and treated or not with mineralocorticoid receptor inhibitor spironolactone. We examined known aldosterone-regulated transcripts involved in corticosteroid signaling and transepithelial ion transport. In addition, we included aldosterone-regulated genes related to cell proliferation. Our comparison revealed multiple aldosterone target genes upregulated in the rat distal colon during decompensated cirrhosis. Epithelial Na+ channel β and γ subunit expression correlated positively with plasma aldosterone concentration and negatively with glomerular filtration rate. Patients with cirrhosis showed increased expression of 11-β-hydroxysteroid-dehydrogenase 2 (11βHSD2), which was reverted by spironolactone treatment, suggesting a sensitization of the distal colon to aldosterone action. In summary, our data show that decaying kidney function during cirrhosis progression toward a decompensated state with hypovolemia correlates with remodeling of distal colon ion transporter expression, supporting a role for aldosterone in the process.NEW & NOTEWORTHY Liver cirrhosis progression significantly alters ion transporter subunit expression in the rat distal colon, a change that correlated well with declining kidney function and the severity of the disease. Our data suggest that the steroid hormone aldosterone participates in this homeostatic response to maintain electrolyte balance.

Modulated Fibrosis and Mechanosensing of Fibroblasts by SB525334 in Pediatric Subglottic Stenosis.

Subglottic stenosis (SGS) may result from prolonged intubation where fibrotic scar tissue narrows the airway. The scar forms by differentiated myofibroblasts secreting excessive extracellular matrix (ECM). TGF-β1 is widely accepted as a regulator of fibrosis; however, it is unclear how biomechanical pathways co-regulate fibrosis. Therefore, we phenotyped fibroblasts from pediatric patients with SGS to explore how key signaling pathways, TGF-β and Hippo, impact scarring and assess the impact of inhibiting these pathways with potential therapeutic small molecules SB525334 and DRD1 agonist dihydrexidine hydrochloride (DHX). Laryngeal fibroblasts isolated from subglottic as well as distal control biopsies of patients with evolving and maturing subglottic stenosis were assessed by α-smooth muscle actin immunostaining and gene expression for α-SMA, FN, HGF, and CTGF markers. TGF-β and Hippo signaling pathways were modulated during TGF-β1-induced fibrosis using the inhibitor SB525334 or DHX and analyzed by RT-qPCR for differential gene expression and atomic force microscopy for ECM stiffness. SGS fibroblasts exhibited higher α-SMA staining and greater inflammatory cytokine and fibrotic marker expression upon TGF-β1 stimulation (p < 0.05). SB525334 restored levels to baseline by reducing SMAD2/3 nuclear translocation (p < 0.0001) and pro-fibrotic gene expression (p < 0.05). ECM stiffness of stenotic fibroblasts was greater than healthy fibroblasts and was restored to baseline by Hippo pathway modulation using SB525334 and DHX (p < 0.01). We demonstrate that distinct fibroblast phenotypes from diseased and healthy regions of pediatric SGS patients respond differently to TGF-β1 stimulation, and SB525334 has the superior potential for subglottic stenosis treatment by simultaneously modulating TGF-β and Hippo signaling pathways. NA Laryngoscope, 134:287-296, 2024.

Histomorphometry of the Sural Nerve for Use as a CFNG in Facial Reanimation Procedures.

Facial palsy (FP) is a debilitating nerve pathology. Cross Face Nerve Grafting (CFNG) describes a surgical technique that uses nerve grafts to reanimate the paralyzed face. The sural nerve has been shown to be a reliable nerve graft with little donor side morbidity. Therefore, we aimed to investigate the microanatomy of the sural nerve. Biopsies were obtained from 15 FP patients who underwent CFNG using sural nerve grafts. Histological cross-sections were fixated, stained with PPD, and digitized. Histomorphometry and a validated software-based axon quantification were conducted. The median age of the operated patients was 37 years (5-62 years). There was a significant difference in axonal capacity decrease towards the periphery when comparing proximal vs. distal biopsies (p = 0.047), while the side of nerve harvest showed no significant differences in nerve caliber (proximal p = 0.253, distal p = 0.506) and axonal capacity for proximal and distal biopsies (proximal p = 0.414, distal p = 0.922). Age did not correlate with axonal capacity (proximal: R = -0.201, p = 0.603; distal: R = 0.317, p = 0.292). These novel insights into the microanatomy of the sural nerve may help refine CFNG techniques and individualize FP patient treatment plans, ultimately improving overall patient outcomes.

The Characteristics of Isolated Bulb Celiac Disease in Children.

Mucosal injury in celiac disease (CD) patients can be patchy, and up to 12% of CD patients can have mucosal changes limited to the duodenal bulb. Hence, recent guidelines recommend obtaining bulb biopsies in addition to distal duodenum. This study aimed to describe a cohort of children with isolated bulb CD and assess the benefit of separating bulb biopsies. A retrospective chart review between January 2011 and January 2022 at 2 medical centers was conducted. We included children with CD who underwent endoscopy with separated biopsies from the bulb and distal duodenum. A blinded pathologist performed Marsh-Oberhuber grading on selected cases. We identified 224 CD patients, of which 33 (15%) had histologically confirmed isolated bulb CD. Patients with isolated bulb CD were older at diagnosis (10 vs 8 years; P = 0.03). Median anti-tissue transglutaminase immunoglobulin A (TTG IgA) level was lower in isolate bulb CD (2.8 vs 16.7 times the upper limit of normal [ULN], P < 0.001). Almost 88% (29/33) of isolated bulb CD patients had an anti-TTG IgA value of less than 10 times the ULN. Time to anti-TTG IgA normalization (mean 14 months) was similar between the 2 groups. A pathologist review of diagnostic biopsies could not distinguish between the bulb and distal duodenum biopsies in approximately one-third of the reviewed samples. Separating bulb from distal duodenum biopsies can be considered during CD diagnosis, particularly in children with anti-TTG IgA levels less than 10 times the ULN. Larger prospective cohorts are needed to decide whether isolated bulb CD is a unique cohort or an early stage of the conventional CD.

P017 Fecal wash host transcriptomics identifies inflammation throughout the colon and terminal ileum

Abstract Background Non-invasive modalities for assessing active endoscopic and histological inflammation in Crohn’s disease and Ulcerative Colitis patients are critically needed. Fecal wash host transcriptomics has been shown to be a robust classifier of endoscopic and histological inflammation in inflammatory bowel disease (IBD) patients with distal colitis. Whether such fecal washes can inform on inflammatory processes occurring in more proximal intestinal segments is currently unknown. Methods Crohn's disease and Ulcerative Colitis patients as well as healthy controls were prospectively enrolled. Host transcriptomes of biopsies and fecal washes obtained during colonoscopy at predefined locations throughout the colon and terminal ileum were analyzed and associated with same time-point clinical, endoscopic and histological parameters. Results 59 IBD patients and 50 controls were prospectively enrolled. Biospies and fecal washes from the distal, proximal colon and terminal ileum were compared. We find that host transcriptomics of distal fecal washes robustly classify histological inflammation in ileal and proximal colonic Crohn’s disease, even without distal colonic involvement. Receiver operating characteristic (ROC) curve analysis demonstrated significantly higher classification power based on the fecal wash transcriptomics compared to biopsies: Area Under the Curve, AUC=0.94+-0.07 for UC distal fecal washes and AUC=0.94+-0.09 for distal fecal washes of CD patients without distal colonic involvement, as compared to all distal biopsies AUC= 0.82+-0.20. We further demonstrate that fecal washes consist of modules of co-expressed immune, stromal and epithelial genes. Fecal wash expression of gene modules previously associated with lack of response to biological therapies correlates with disease severity. Figure 1 - Host transcriptomics of fecal washes from different intestinal segments captures information that is distinct from same – segment biopsy transcriptomics. A) Experimental layout. B) Clustergram of transcriptomes of biopsies (purple) and fecal washes (yellow). C) Principal component analysis (PCA) of biopsies (purple) and fecal washes (yellow). Black circles highlight inflamed samples. D) Spearman correlations between the transcriptomes of pairs of either biopsies or fecal washes that are both annotated as inflamed and mixed pairs (one annotated as inflamed and the other not). (A) Created with BioRender.com. TI – terminal ileum, P – proximal colon, D – distal colon. Conclusion Our study establishes the power of colonic fecal washes for identifying pathological processes throughout the ileal-colonic axis.

Celiac Disease Diagnosis Via Histopathological Correlation of Duodenal Biopsies in Children

Aim: The purpose of this study is to compare the diagnostic accuracy of duodenal bulb biopsies to distal duodenal biopsies in patients suspected of having celiac disease. Study Design: Cross-sectional study Place and Duration: This study was conducted at Department of Pathology, The children's hospital &amp; The institute of child health, Multan during the period from April, 2022 to September, 2022. Methods: Total 86 children of celiac disease were presented in this study. Informed written consent provided by parents of children for the collection of detailed demographic data. Under general anaesthesia, a duodenal bulb sample and four distal duodenum samples were collected during an upper gastrointestinal endoscopy. Histological alterations indicative with CD were identified. Histological diagnosis and grading were performed using a modification of the Marsh-Oberhuber classification. The entire data set was analyzed by using SPSS 20.0. Results: Forty nine (56.97%) patients were females and 37 (43.03%) cases were males. Children’s mean age was 6.4±3.27 years with mean weight 15.9±6.19 kg. Mean height of the cases was 94.7±10.42 cm. There were 51 (59.3%) children had urban residency. According to marsh grading, 50 (58.1%) cases had grade IIIC. We found that frequency of crypt hyperplasia, influx of immune cells in lamina propria and enterocytes change in both duodenal bulb and distal part biopsies were equal while only frequency of villous atrophy and intraepithelial lymphocytes were different in both biopsies. 96.5% patients reported a high level of correlation, while only 3.5% reported no correlation. Conclusion: Both biopsy sites agree strongly. We may now suggest duodenal bulb biopsy alone. Since the endoscopic method of distal duodenum is laborious and requires more knowledge and time, obtaining biopsies from the proximal section is easier and requires less experience, therefore this strategy may be used even at facilities with junior paediatric gastroenterologists. Keywords: Celiac disease, Children, Histopathology, Duodenal bulb, Distal duodenum

Small fiber involvement is independent from clinical pain in late-onset Pompe disease

BackgroundPain occurs in the majority of patients with late onset Pompe disease (LOPD) and is associated with a reduced quality of life. The aim of this study was to analyse the pain characteristics and its relation to a small nerve fiber involvement in LOPD patients.MethodsIn 35 patients with LOPD under enzyme replacement therapy without clinical signs of polyneuropathy (19 females; 51 ± 15 years), pain characteristics as well as depressive and anxiety symptoms were assessed using the PainDetect questionnaire (PDQ) and the hospital anxiety and depression scale (HADS), respectively. Distal skin biopsies were analysed for intraepidermal nerve fiber density (IENFD) and compared to age- and gender-matched reference data. Skin biopsies from 20 healthy subjects served as controls to assure validity of the morphometric analysis.ResultsPain was reported in 69% of the patients with an average intensity of 4.1 ± 1.1 on the numeric rating scale (NRS; anchors: 0–10). According to PDQ, neuropathic pain was likely in one patient, possible in 29%, and unlikely in 67%. Relevant depression and anxiety symptoms occurred in 31% and 23%, respectively, and correlated with pain intensity. Distal IENFD (3.98 ± 1.95 fibers/mm) was reduced in 57% of the patients. The degree of IENFD reduction did not correlate with the durations of symptoms to ERT or duration of ERT to biopsy.ConclusionsPain is a frequent symptom in treated LOPD on ERT, though a screening questionnaire seldom indicated neuropathic pain. The high frequency of small nerve fiber pathology in a treated LOPD cohort was found regardless of the presence of pain or comorbid risk factors for SFN and needs further exploration in terms of clinical context, exact mechanisms and when developing novel therapeutic options for LOPD.

The Potential Role for Impaired Mucosal Integrity in the Generation of Esophageal Pain Using Capsaicin in Humans: An Explorative Study.

INTRODUCTION:Esophageal pain is mediated by sensory nerves, most importantly by the activation of the transient receptor potential vanilloid 1 (TRPV1) capsaicin receptor. TRPV1 is activated and sensitized by a broad range of pungent compounds, as well as inflammatory mediators and tissue irritants. Luminal stressors are suggested to impair the barrier function, which results in consequent activation of these sensory nerve terminals and pain. In this study, we investigated the effect of the perfusion of capsaicin, a TRPV1 agonist, on mucosal impedance and pain in asymptomatic volunteers.METHODS:Thirteen asymptomatic volunteers completed a single-blind, saline-controlled, randomized crossover study. Capsaicin or saline was perfused for 30 minutes in the distal esophagus. Visual analog scale pain intensity scores and intraluminal impedance indicating mucosal integrity were determined. Distal and proximal biopsies were obtained 10 minutes later to measure TRPV1 messenger RNA and TRPV1 immunopositivity, as well as the intercellular space area.RESULTS:Capsaicin perfusion resulted in significantly greater pain intensity (P = 0.047) and impaired recovery of the mucosal impedance compared with saline-treated controls (P = 0.027). Pain response was significantly associated with decreased mucosal impedance. Similar dynamics were seen in the proximal esophagus, but mucosal impedance recovered entirely to the preinfusion values there. There was a significant association between mucosal impedance and intercellular space width in the distal esophagus. TRPV1 transcription and expression were not significantly altered within this observation period.DISCUSSION:Esophageal capsaicin perfusion results in pain, which is likely to be explained by impaired mucosal impedance and defective restoration capacity in the distal esophagus.

Mycobacterium leprae induces Schwann cell proliferation and migration in a denervated milieu following intracutaneous excision axotomy in nine-banded armadillos

Nine–banded armadillos develop peripheral neuropathy after experimental Mycobacterium leprae infection that recapitulates human disease. We used an intracutaneous excision axotomy model to assess the effect of infection duration by M. leprae on axonal sprouting and Schwan cell density.34 armadillos (17 naïve and 17 M. leprae-infected) underwent 3 mm skin biopsies to create an intracutaneous excision axotomy followed by a concentric 4-mm overlapping biopsy 3 and 12-months post M. leprae inoculation. A traditional distal leg biopsy was obtained at 15mo for intraepidermal nerve fiber (IENF) density. Serial skin sections were immunostained against a axons (PGP9.5, GAP43), and Schwann cells (p75, s100) to visualize regenerating nerves. Regenerative axons and proliferation of Schwann cells was measured and the rate of growth at each time point was assessed. Increasing anti-PGL antibody titers and intraneural M. leprae confirmed infection.15mo following infection, there was evidence of axon loss with reduced distal leg IENF versus naïve armadillos, p < 0.05. This was associated with an increase in Schwann cell density (11,062 ± 2905 vs. 7561 ± 2715 cells/mm3, p < 0.01). Following excisional biopsy epidermal reinnervation increased monotonically at 30, 60 and 90 days; the regeneration rate was highest at 30 days, and decreased at 60 and 90 days. The reinnervation rate was highest among animals infected for 3mo vs those infected for 12mo or naïve animals (mean ± SD, 27.8 ± 7.2 vs.16.2 ± 5.8vs. 15.3 ± 6.5 mm/mm3, p < 0.05). The infected armadillos displayed a sustained Schwann cell proliferation across axotomy time points and duration of infection (3mo:182 ± 26, 12mo: 256 ± 126, naive: 139 ± 49 cells/day, p < 0.05).M. leprae infection is associated with sustained Schwann cell proliferation and distal limb nerve fiber loss. Rates of epidermal reinnervation were highest 3mo after infection and normalized by 12 mo of infection. We postulate that excess Schwann cell proliferation is the main pathogenic process and is deleterious to sensory axons. There is a compensatory initial increase in regeneration rates that may be an attempt to compensate for the injury, but it is not sustained and eventually followed by axon loss. Aberrant Schwann cell proliferation may be a novel therapeutic target to interrupt the pathogenic cascade of M. leprae.

Prognostic value of cutaneous reinnervation with GAP-43 in oxaliplatin-induced neuropathy

Background and purposeOxaliplatin-induced neuropathy (OIN) implies axonal damage of both small and large sensory nerve fibers. We aimed at comparing the neurophysiological changes occurred after treatment and the capability to recovery based on histological marker of re-innervation GAP-43.Methods48 patients with cancer were assessed before and after chemotherapy (at 3 months and 12 months if available). We recorded ulnar and sural sensory nerve action potentials (SNAP), determined quantitative sensory thresholds for warm and cold (WDT, CDT), pain thresholds and collected a distal biopsy of skin to assess the intra-epidermal nerve fiber density (IENFD) with PGP9.5 and GAP-43 markers (in a subgroup of 19 patients).ResultsIncreased WDT and CDT as well as diminished IENFD at distal leg were already found in 30% of oncologic patients before treatment. After oxaliplatin, there was a significant increase in thermal thresholds in 52% of patients, and a decrease of SNAP amplitude in the sural nerve in 67% patients. IENFD was reduced in 47% and remained unchanged in 37% after oxiplatin. The density of GAP-43 + fibers and GAP-43/PGP 9.5 ratio was similar before and after treatment showing that cutaneous re-innervation is preserved despite no clinical recovery was observed after one year.ConclusionNon-selective axonal loss affects sensory fibers in OIN. However, the presence of intra-epidermal regenerative sprouts detected by GAP-43 may reduce the impact of neurotoxicity in the small fibers with long-term sequelae mostly on myelinated nerve endings. Pre-oxaliplatin GAP-43 failed to identify patients with higher risk of damage or worse recovery after treatment.

Small fiber neuropathy.

Small fiber neuropathy (SFN) is a peripheral nervous system disease due to affection of A-delta or C-fibers in a proximal, distal, or diffuse distribution. Selective SFN (without large fiber affection) manifests with pain, sensory disturbances, or autonomic dysfunction. Though uniform diagnostic criteria are unavailable, most of them request typical clinical features and reduced intra-epidermal nerve fiber density on proximal or distal skin biopsy. Little consensus has been reached about the treatment of SFN, why this narrative review aims at summarizing and discussing treatment options for SFN. Treatment of SFN can be classified as symptomatic, pathophysiologic, or causal. Prerequisites for treating SFN are an established diagnosis, knowledge about the symptoms and signs, and the etiology. Pain usually responds to oral/intravenous pain killers, antidepressants, anti-seizure drugs, or topical, transdermal specifications. Some of the autonomic disturbances respond favorably to symptomatic treatment. SFN related to Fabry disease or hATTR are accessible to pathogenesis-related therapy. Immune-mediated SFN responds to immunosuppression or immune-modulation. Several of the secondary SFNs respond to causal treatment of the underlying disorder. In conclusion, treatment of SFN relies on a multimodal concept and includes causative, pathophysiologic, and symptomatic measures. It strongly depends on the clinical presentation, diagnosis, and etiology, why it is crucial before initiation of treatment to fix the diagnosis and etiology. Due to the heterogeneous clinical presentation and multi-causality, treatment of SFN should be individualized with the goal of controlling the underlying cause, alleviating pain, and optimizing functionality.

Defining the Patchy Landscape of Esophageal Eosinophilia in Children With Eosinophilic Esophagitis

Eosinophilic esophagitis (EoE) is a patchy disease of the esophagus with significant variability in intraepithelial eosinophilia. Three biopsies each from distal and proximal esophagus are recommended for identification of active EoE. Recent work suggests 3 biopsy sites are more optimal. We sought to evaluate 2-site vs 3-site esophageal biopsy combinations for utility to identify active EoE. We prospectively obtained 3-site esophageal biopsies based on rigorous endoscopic measurements of the proximal, mid, and distal esophagus and gastroesophageal junction. Biopsies were reviewed by a pathologist, and those with at least 15 eosinophils per high-power field were considered active EoE. The sensitivity of one or more sites to identify active EoE was determined, and endoscopic measurements were correlated to height and age. Five hundred ninety-six endoscopies were performed in 217 patients; of these, 304 endoscopies in 167 patients had active EoE. Among the initial esophagogastroduodenoscopies with active EoE, distal biopsies had greater than 80% sensitivity, whereas mid and proximal biopsies had sensitivity of 65% and 62%, respectively, and distal+ proximal biopsies had the highest diagnostic sensitivity for a 2-site combination. Among the 304 endoscopies with active EoE, 9 had focal eosinophilia restricted to the mid esophagus, and 8 were restricted to the proximal esophagus. For patients with multiple endoscopies with active EoE, nearly one fourth had reduced sites with eosinophilia at the second time point. Endoscopic measurements strongly correlated with height and age. This study supports endoscopic measurement-guided 3-site biopsies for optimal disease assessment of active EoE in children.

Flexible sigmoidoscopy may be sufficient for initial evaluation of suspected immunotherapy-mediated colitis: A cross-sectional study.

Immune checkpoint inhibitors (ICIs) have shown promise in treating a variety of cancers. Their increased use coincides with increased incidence of immunotherapy-mediated colitis (IMC), a common adverse effect. Optimal strategy for endoscopic evaluation of IMC (full colonoscopy or flexible sigmoidoscopy) is not well-defined. Retrospective review of all patients at City of Hope referred to gastroenterology for evaluation of IMC due to gastrointestinal symptoms was performed. Patients with an existing histologic diagnosis of IMC established at an outside hospital or a diagnosis of infectious or chronic colitis were excluded. We identified 51 symptomatic patients on ICIs prompting evaluation for IMC with colonoscopy (47/51) or flexible sigmoidoscopy (4/51). All distal rectosigmoid biopsies during flexible sigmoidoscopy demonstrated histologic evidence of IMC. In full colonoscopy, IMC was either present in all segments of colon simultaneously (35/47) or absent from all segments (12/47). No isolated proximal colonic biopsies demonstrated IMC. Endoscopically normal mucosa demonstrated histologic evidence of IMC up to 68.6% of the time. Endoscopically abnormal right, transverse, and left colon had low sensitivity (35.3%, 34.3%, and 41.7%, respectively) and high specificity (100.0%, 100.0%, and 91.7%, respectively) for histological presence of IMC. Distal colon biopsies in patients on ICI therapy with diarrhea and suspected IMC were sufficient for diagnosing IMC in our cohort. Further, we found histologic evidence of IMC in biopsies taken from normal-appearing mucosa in a number of patients, suggesting that a normal endoscopic appearance does not preclude the presence of IMC and biopsies should be taken from both normal and abnormal-appearing mucosa.

Endoscopic tissue sampling - Part 1: Upper gastrointestinal and hepatopancreatobiliary tracts. European Society of Gastrointestinal Endoscopy (ESGE) Guideline.

1: ESGE recommends that, where there is a suspicion of eosinophilic esophagitis, at least six biopsies should be taken, two to four biopsies from the distal esophagus and two to four biopsies from the proximal esophagus, targeting areas with endoscopic mucosal abnormalities. Distal and proximal biopsies should be placed in separate containers.Strong recommendation, low quality of evidence. 2: ESGE recommends obtaining six biopsies, including from the base and edge of the esophageal ulcers, for histologic analysis in patients with suspected viral esophagitis.Strong recommendation, low quality of evidence. 3: ESGE recommends at least six biopsies are taken in cases of suspected advanced esophageal cancer and suspected advanced gastric cancer.Strong recommendation, moderate quality of evidence. 4: ESGE recommends taking only one to two targeted biopsies for lesions in the esophagus or stomach that are potentially amenable to endoscopic resection (Paris classification 0-I, 0-II) in order to confirm the diagnosis and not compromise subsequent endoscopic resection.Strong recommendation, low quality of evidence. 5: ESGE recommends obtaining two biopsies from the antrum and two from the corpus in patients with suspected Helicobacter pylori infection and for gastritis staging.Strong recommendation, low quality of evidence. 6: ESGE recommends biopsies from or, if endoscopically resectable, resection of gastric adenomas.Strong recommendation, moderate quality of evidence. 7: ESGE recommends fine-needle aspiration (FNA) and fine-needle biopsy (FNB) needles equally for sampling of solid pancreatic masses.Strong recommendation, high quality evidence. 8: ESGE suggests performing peroral cholangioscopy (POC) and/or endoscopic ultrasound (EUS)-guided tissue acquisition in indeterminate biliary strictures. For proximal and intrinsic strictures, POC is preferred. For distal and extrinsic strictures, EUS-guided sampling is preferred, with POC where this is not diagnostic.Weak recommendation, low quality evidence. 9: ESGE suggests obtaining possible non-neoplastic biopsies before sampling suspected malignant lesions to prevent intraluminal spread of malignant disease.Weak recommendation, low quality of evidence. 10: ESGE suggests dividing EUS-FNA material into smears (two per pass) and liquid-based cytology (LBC), or the whole of the EUS-FNA material can be processed as LBC, depending on local experience.Weak recommendation, low quality evidence.

Pure Motor Onset and IgM-Gammopathy Occurrence in Multifocal Acquired Demyelinating Sensory and Motor Neuropathy.

To longitudinally investigate patients with multifocal acquired demyelinating sensory and motor neuropathy (MADSAM), quantifying timing and location of sensory involvements in motor onset patients, along with clinicohistopathologic and electrophysiologic findings to ascertain differences in patients with and without monoclonal gammopathy of uncertain significance (MGUS). Patients with MADSAM seen at Mayo Clinic and tested for monoclonal gammopathy and ganglioside antibodies were retrospectively reviewed (January 1, 2007-December 31, 2018). Of 76 patients with MADSAM, 53% had pure motor, 16% pure sensory, 30% sensorimotor, and 1% cranial nerve onsets. Motor-onset patients were initially diagnosed with multifocal motor neuropathy (MMN). MGUS occurred in 25% (89% immunoglobulin M [IgM] subtype), associating with ganglioside autoantibodies (p < 0.001) and higher IgM titers (p < 0.04). Median time to sensory involvements (confirmed by electrophysiology) in motor onset patients was 18 months (range 6-180). Compared to initial motor nerve involvements, subsequent sensory findings were within the same territory in 35% (14/40), outside in 20% (8/40), or both in 45% (18/40). Brachial and lumbosacral plexus MRI was abnormal in 87% (34/39) and 84% (21/25), respectively, identifying hypertrophy and increased T2 signal predominantly in brachial plexus trunks (64%), divisions (69%), and cords (69%), and intrapelvic sciatic (64%) and femoral (44%) nerves. Proximal fascicular nerve biopsies (n = 9) more frequently demonstrated onion-bulb pathology (p = 0.001) and endoneurial inflammation (p = 0.01) than distal biopsies (n = 17). MRI and biopsy findings were similar among patient subgroups. Initial Inflammatory Neuropathy Cause and Treatment (INCAT) disability scores were higher in patients with MGUS relative to without (p = 0.02). Long-term treatment responsiveness by INCAT score reduction ≥1 or motor Neuropathy Impairment Score (mNIS) >8-point reduction occurred in 75% (49/65) irrespective of MGUS or motor onsets. Most required ongoing immunotherapy (86%). Patients with MGUS more commonly required dual-agent immunotherapy for stability (p = 0.02). Pure motor onsets are the most common MADSAM presentation. Long-term follow-up, repeat electrophysiology, and nerve pathology help distinguish motor onset MADSAM from MMN. Better long-term immunotherapy responsiveness occurs in motor onset MADSAM compared to MMN reports. Patients with MGUS commonly require dual immunotherapy. This study provides Class II evidence that most clinical, electrophysiologic, and histopathologic findings were similar between patients with MADSAM with and without MGUS.

Diagnostic merits of the Eosinophilic Esophagitis Diagnostic Panel from a single esophageal biopsy

Eosinophilic esophagitis (EoE) is a histologically "patchy" disease with uneven eosinophil distribution along the esophagus, posing a dilemma for histologically analyzing endoscopic biopsy samples, especially when biopsy samples are limited to only the distal esophagus. We investigated whether molecular mRNA profiling of a distal esophageal biopsy sample predicts eosinophilia in the proximal esophagus. Esophageal biopsy samples (n= 507) from subjects with EoE were collected from multiple institutions, spanning adults and pediatric patients. Subjects were grouped on the basis of distinct distal (D) and proximal (P) eosinophil counts (D+P+, D+P-, D-P+, and D-P-, with+ and - defined as ≥15 or <15 eosinophils/hpf, respectively). Molecular profiles were assessed by using the EoE Diagnostic Panel (EDP), a set of 96 esophageal transcripts used to derive the EDP score. The distal EDP score was correlated with proximal eosinophil levels (r= -0.73; P< .0001). EDP analysis of a histologically negative distal biopsy sample predicted the presence of proximal esophagitis with high sensitivity (85%). In a 2-year follow-up focusing on the cases with discordant histologic and EDP results, histologically negative patients (D-P-) had higher rates of EoE relapse when the EDP was positive than when the EDP was negative (odds ratio= 11; P=.003), indicating predictive medicine capacity. EDP analysis of a single distal esophageal biopsy sample predicts remote inflammation in patients with spatially heterogeneous eosinophilia and disease relapse in patients with histologic remission, providing diagnostic merit and predictive medicine capacity for molecular diagnosis of EoE.