Eosinophilic Gastrointestinal Disease.

This JAMA Insights Clinical Update discusses the symptoms, diagnosis, and management of eosinophilic gastrointestinal diseases.

Nutritional Aspects of Pediatric Gastrointestinal Diseases.

In the last decade, the role of nutritional management in pediatric gastrointestinal diseases has gained increasing popularity. Disease-specific diets have been introduced as conventional treatments by international guidelines. Patients tend to more willingly accept food-based therapies than drugs because of their relatively "harmless" nature. Apart from a diet's therapeutic role, nutritional support is crucial in maintaining growth and improving clinical outcomes in pediatric patients. Despite the absence of classical "side effects", however, it should be emphasized that any dietary modification might have negative consequences on children's growth and development. Hence, expert supervision is always advised, in order to support adequate nutritional requirements. Unfortunately, the media provide an inaccurate perception of the role of diet for gastrointestinal diseases, leading to misconceptions by patients or their caregivers that tends to overestimate the beneficial role of diets and underestimate the potential adverse effects. Moreover, not only patients, but also healthcare professionals, have a number of misconceptions about the nutritional benefits of diet modification on gastrointestinal diseases. The aim of this review is to highlight the role of diet in pediatric gastrointestinal diseases, to detect misconceptions and to give a practical guide for physicians on the basis of current scientific evidence.

Clinical and pathophysiological characteristics of valproate-induced pleural effusion.

INTRODUCTION: Valproic acid is a carboxylic acid derivative commonly prescribed for several types of seizure disorders or for acute manic episodes in patients with bipolar disorder. Several cases of valproate-induced pleural effusion have been reported, although the precise pathophysiological mechanism remains unknown. OBJECTIVE: To describe the presentation of pleural effusion associated with valproate use and to categorize published case reports according to clinical, immunological, and pleural effusion cell type. METHODS: PubMed/MEDLINE and Embase databases were systematically searched from January 1970 until November 2020 using the following search terms: "valproic acid" OR "valproate" OR "pleural fluid" OR "exudative effusion" OR "transudative effusion" OR "valproic lung adverse events". These searches yielded 171 references of which 135 articles were considered irrelevant, leaving 36 potentially relevant references which were carefully scrutinized. Twenty-eight cases of valproate-induced pleural effusion were identified after excluding two articles reporting five patients with lung parenchymal adverse reactions to treatment with valproic acid; two articles reporting three patients in whom the pleural effusion could not be attributed to valproic acid alone; one case discussing valproate therapy and fungal pleural effusion; and one describing a patient who suffered from severe cardiac failure. There were also two cases, in an abstract form, with pericardial and pleural effusion, but without any further informative details, and, thus, they were also excluded from this survey. EXUDATIVE EOSINOPHILIC PLEURAL EFFUSION: This was the most common type of valproate-induced pleural effusion reported in 17 out of 28 cases (60.7%), with concurrent peripheral eosinophilia in ten. Acute hypersensitivity reaction, inflammation of the pleural cavity induced by the drug, drug toxicity, and damage to mesothelial cells due to oxidants, comprise the possible pivotal mechanisms. EXUDATIVE LYMPHOCYTIC PLEURAL EFFUSION: This was reported in two cases, with concurrent pericardial effusion in one. Discontinuation of valproate led to resolution of the effusion, although the underlying pathophysiological mechanisms remain abstruse. Interestingly, a patient presented with recurrent pleural effusion characterized by transition from eosinophilic to lymphocytic predominance after readministration of valproate. TRANSUDATIVE PLEURAL EFFUSION: Three out of 28 cases (10.7%) were characterized by neutrophilic transudative pleural effusion after long-term therapy with valproate, while concurrent pericardial effusion was also noted in two. VALPROATE-INDUCED LUPUS ERYTHEMATOSUS WITH PLEURAL EFFUSION: Five patients receiving valproate therapy (17.9% out of the 28 cases) developed drug-induced lupus erythematosus with concurrent pleural effusion that was eosinophilic in three. All patients had positive antinuclear antibodies; anti-histone antibodies were positive in two. CONCLUSIONS: Valproate-induced pleural effusion is rare, but patients receiving treatment with valproic acid who develop respiratory symptoms should be examined for valproate-induced pleural effusion.

Outdoor pollen-related changes in lung function and markers of airway inflammation: A systematic review and meta-analysis.

BACKGROUND: Experimental challenge studies have shown that pollen can have early and delayed effects on the lungs and airways. Here, we qualitatively and quantitatively synthesize the evidence of outdoor pollen exposure on various lung function and airway inflammation markers in community-based studies. METHODS: Four online databases were searched: Medline, Web of Science, CINAHL and Google Scholar. The search strategy included terms relating to both exposure and outcomes. Inclusion criteria were human-based studies published in English that were representative of the community. Additionally, we only considered cross-sectional or short-term longitudinal studies which investigated pollen exposure by levels or season. Study quality assessment was performed using the Newcastle-Ottawa scale. Meta-analysis was conducted using random-effects models. RESULTS: We included 27 of 6551 studies identified from the search. Qualitative synthesis indicated associations between pollen exposure and predominantly type-2 inflammation in both the upper and lower airways, but little evidence for lung function changes. People with ever asthma and/or seasonal allergic rhinitis (SAR) were at higher risk of such airway inflammation. Meta-analysis confirmed a positive relationship between pollen season, eosinophilia and eosinophil cationic protein (ECP) in people with ever SAR but the results between studies were highly variable. Heterogeneity was reduced after further subgrouping by age, and the forest plots indicated that eosinophilic airway inflammation to outdoor pollen exposure increased with age. CONCLUSION: Among people with ever asthma and ever SAR, exposure to increased ambient pollen triggers type-2 upper and lower airway inflammation rather than a non-specific or innate inflammation. These findings can lead to the formulation of specific pollen immunotherapy for susceptible individuals. Future research should be directed towards investigating lagged associations and effect modifications using larger and more generalized populations. SYSTEMATIC REVIEW REGISTRATION: CRD42020146981 (PROSPERO).

Disease Course and Treatment Response of Eosinophilic Gastrointestinal Diseases in Children With Liver Transplantation: Long-Term Follow-Up.

INTRODUCTION: To describe the clinical and laboratory profile, natural course, treatment outcome, and risk factors of posttransplant esophageal and nonesophageal eosinophilic gastrointestinal disorders (EGIDs). METHODS: All children (aged <18 years) who underwent liver transplantation, between 2011 and 2019, in a single transplant center with a follow-up period of 1 year or more posttransplant and with a history of posttransplant endoscopic evaluation were included in this study. RESULTS: During the study period, 89 children met the inclusion criteria. Patients were followed for a median of 8.0 years. A total of 39 (44%) patients were diagnosed with EGID after transplantation. Of these, 29 (33%) had eosinophilic esophagitis (EoE), and 10 (11%) had eosinophilic gastritis, gastroenteritis or enterocolitis. In comparison with the non-EGID group, patients with EGID were younger at transplant (P ≤ 0.0001), transplanted more frequently due to biliary atresia (P ≤ 0.0001), and had higher rates of pretransplant allergy (P = 0.019). In the posttransplant period, they had higher rates of mammalian Target of Rapamycin inhibitor use (P = 0.006), Epstein-Barr virus viremia (P = 0.03), post-transplant lymphoproliferative disease (P = 0.005), and allergen sensitization (P ≤ 0.0001). In regression analysis, young age at transplant, age at diagnosis, pretransplant atopic dermatitis, and post-transplant lymphoproliferative disease were associated with an increased risk of EGID or EoE. Laboratory abnormalities such as anemia (P = 0.007), thrombocytosis (P = 0.012), and hypoalbuminemia (P = 0.031) were more commonly observed in the eosinophilic gastritis, gastroenteritis or enterocolitis group than in the EoE group. Following treatment, most patients had symptomatic resolution at 3 months and histologic resolution at 6 months postdiagnosis. Among the patients who had 5 years of follow-up, none recurred. DISCUSSION: EGID is a common posttransplant diagnosis, which seems to affect patients who are transplanted earlier and who have pretransplant atopy. Posttransplant EGID is responsive to treatment, but as histologic remission occurs after symptomatic resolution, the decision to perform control endoscopy should be delayed.

Short-term use of "ECMELLA" in the context of fulminant eosinophilic myocarditis with cardiogenic shock.

BACKGROUND: Eosinophilic myocarditis (EM) is a rare form of myocarditis. Clinical presentation is various, includes cardiogenic shock and can often be fatal. Diagnosis is based on myocardial eosinophilic infiltration in endomyocardial biopsy. Mechanical circulatory support (MCS) is often required in patients suffering from severe cardiogenic shock. Among the available MCS options the "ECMELLA" concept, a combination of left ventricular venting by Impella® device and extracorporeal life support (ECLS) is possibly able to provide the necessary time frame for diagnostics and initiation of anti-inflammatory medication in patients with fulminant myocarditis. CASE PRESENTATION: We report a case of a 38-year-old woman who was presented to us in severe cardiogenic shock, quickly requiring hemodynamic support by an Impella CP® device. Further dramatic hemodynamic deterioration accompanied by multi-organ dysfunction required escalation of MCS via ECLS as veno-arterial extracorporeal membrane oxygenation (VA-ECMO). After histopathological diagnosis of EM, our patient was put on immunosuppressive therapy with prednisolone. Recovery of both right and left ventricular function allowed explanation of VA-ECMO on day 4 and further hemodynamic improvement allowed removal of the Impella® device on day 9. The patient was discharged after 7 weeks with fully restored cardiac function and in a good neurological state. CONCLUSIONS: In severe cardiac shock due to fulminant EM the ECMELLA concept as bridge-to-recovery seems to be a valid option to provide the required time for diagnostics and specific therapy.

Comparison of olfactory and taste functions between eosinophilic and non-eosinophilic chronic rhinosinusitis.

OBJECTIVE: Most patients with chronic rhinosinusitis (CRS) complain of olfactory and/or taste dysfunctions. However, olfactory and taste dysfunctions depending on the subtype of CRS, classified as eosinophilic CRS (ECRS) and non-eosinophilic CRS (NCRS), have not been clearly reported. Therefore, the purpose of this study was to investigate the clinical features in olfactory and taste functions according to the subtype classified as ECRS and NCRS. METHODS: We retrospectively analyzed the electronic medical records of patients who underwent endoscopic sinus surgery and were diagnosed with CRS. The patients were divided into ECRS and NCRS groups, according to their Japanese Epidemiological Survey of Refractory Eosinophilic Chronic Rhinosinusitis (JESREC) scores. We analyzed demographic characteristics, Sino-Nasal Outcome Test findings, Lund-Mackay score, and the results of previously-validated tests, including the Korean Version of Sniffin' Stick test and chemical gustatory function test. RESULTS: Patients with ECRS and NCRS had decreased olfactory and taste functions compared to the control group. In particular, the olfactory score of ECRS patients was lower than that of NCRS patients (18.1 ± 9.5 vs 23.7 ± 8.5, respectively, p <0.001). On the other hand, taste scores of ECRS patients were not statistically different compared to NCRS patients (19.1 ± 4.7 vs. 18.3 ± 4.7, respectively, p = 0.166). Olfactory score decreased with increase in JESREC score (r=-0.203, p = 0.002), but it had no correlation with taste score (r = 0.072, p = 0.276). CONCLUSION: We found a difference in olfactory function but no difference in taste function between patients in ECRS and NCRS groups. These results may provide valuable clinical features in terms of olfactory and taste functions according to the subtypes of CRS.

Real-life evaluation of mepolizumab efficacy in patients with severe eosinophilic asthma, according to atopic trait and allergic phenotype.

BACKGROUND: Anti-interleukin-5 (IL-5) monoclonal antibodies can be used as add-on biological therapies in allergic and non-allergic patients with severe eosinophilic asthma. However, within such a therapeutic context real-life investigations are lacking. OBJECTIVE: Therefore, the aim of the present observational study was to evaluate the effects of mepolizumab in allergic and non-allergic subjects with severe eosinophilic asthma. METHODS: Relevant clinical, functional, laboratory, and pharmacotherapeutic parameters were assessed in the above patient subgroups. RESULTS: After one year of add-on biological treatment with mepolizumab, our 88 patients experienced a remarkable improvement of their severe asthma, documented by a better symptom control, expressed by a significant improvement in asthma control test (ACT) score. Indeed, the mean value (±standard deviation) of ACT score increased from 12.55 (±3.724) to 21.08 (±3.358). Moreover, significant improvements were also detected with regard to the median values (interquartile range) of forced expiratory volume in one second (FEV1 ), blood eosinophil numbers, annual rate of disease exacerbations, and daily intake of oral corticosteroids (OCS). In particular, FEV1 enhanced from 1640 mL (1110-2275) to 1920 mL (1525-2615), blood eosinophil count dropped from 711.0 cells/µL (500.0-1022) to 90.00 cells/µL (50.00-117.5), the annual rate of asthma exacerbations decreased from 3.000 (2.000-6.000) to 0.000 (0.000-1.000), and the daily prednisone intake fell from 6.250 mg (0.000-25.00) to 0.000 mg (0.000-0.000). After one year of mepolizumab treatment, the improvements in clinical, functional, and haematological parameters were quite similar in patient subgroups characterized by skin prick test (SPT) negativity or positivity, respectively. A significant correlation was observed between serum IgE levels and OCS intake decrease (r = -0.2257; P < .05). CONCLUSION AND CLINICAL RELEVANCE: Hence, our real-life data suggest that mepolizumab can represent a valid add-on therapeutic option for patients with severe eosinophilic asthma, irrespective of IgE serum concentrations, and allergic sensitization.

Relationship of Blood Eosinophils with Fractional Exhaled Nitric Oxide and Pulmonary Function Parameters in Chronic Obstructive Pulmonary Disease (COPD) Exacerbation.

BACKGROUND The 2018 Global Initiative for Chronic Obstructive Lung Disease Report reveals that the blood eosinophil count could forecast the risk of flare-ups. This study explored the correlations of blood eosinophils with fractional exhaled nitric oxide (FeNO) and pulmonary function parameters in acute exacerbation of chronic obstructive pulmonary disease (AECOPD). MATERIAL AND METHODS The data of patients with AECOPD at our hospital admitted between July 2018 and June 2019 were retrospectively analyzed. All patients were stratified into an eosinophilic group (≥2%) or a noneosinophilic group (<2%) based on the peripheral eosinophil count per centum. Cross-sectional analysis was performed to compare clinical characteristics, percentage of eosinophils, FeNO, and pulmonary function between the 2 groups. RESULTS After applying the inclusion/exclusion criteria, 247 patients were included. FeNO values were higher in eosinophilic group (n=97) than in noneosinophilic group (n=150) (P=0.005). The forced expiratory volume in 1 second% predicted (FEV1% predicted), FEV1, and forced vital capacity (FVC) were higher in the eosinophilic group than in the noneosinophilic group (P=0.043; P=0.040; and P=0.011, respectively). Blood eosinophilia showed positive correlations with FeNO (P=0.004) and spirometry variables (FEV1 [% predicted], P=0.003; FEV1, P<0.001; and FVC, P<0.001). An FeNO level of 22.5 ppb was the best cutoff value to predict blood eosinophilia (P=0.000). CONCLUSIONS Blood eosinophil count is a likely biomarker that can predict positive relationship with FeNO values and pulmonary function parameters.

Effect of Anti-IL5, Anti-IL5R, Anti-IL13 Therapy on Asthma Exacerbations: A Network Meta-analysis.

BACKGROUND: Several new treatments for severe asthma have become available in the last decade; yet, little data exist to guide their use in specific patient populations. OBJECTIVE: A network meta-analysis was conducted comparing the efficacy of FDA-approved monoclonal antibody therapies in preventing exacerbations in patients with severe eosinophilic asthma. METHODS: PubMed and Ovid were searched from inception until July 2019 for randomized controlled trials that studied the efficacy of benralizumab, dupilumab, mepolizumab, and reslizumab, in preventing acute exacerbations of asthma. Studies were included if they reported data for patients with severe eosinophilic asthma (defined in this meta-analysis as absolute eosinophil count ≥ 250 cells/µL). Annualized rate ratios for asthma exacerbations (during treatment) were calculated and converted to log rate ratios. Direct and indirect treatment estimates (for inter-drug differences) were analyzed using frequentist network meta-analysis methodology in R and treatments were ranked based on P-scores. RESULTS: In total, nine studies were included in the final analysis. Network meta-analysis revealed that all drugs were superior to placebo in preventing rates of asthma exacerbation in the study population and no inter-drug differences existed. Dupilumab was found to have the greatest magnitudes of effect on decreasing log rate ratio of asthma exacerbation based on P-score (0.83). CONCLUSION: Benralizumab, dupilumab, mepolizumab, and reslizumab are all associated with decreased asthma exacerbations in patients with eosinophilic asthma, with no significant inter-drug differences.

Understanding the immunology of asthma: Pathophysiology, biomarkers, and treatments for asthma endotypes.

Asthma is a common disease in paediatrics and adults with a significant morbidity, mortality, and financial burden worldwide. Asthma is now recognized as a heterogeneous disease and emerging clinical and laboratory research has elucidated understanding of asthma's underlying immunology. The future of asthma is classifying asthma by endotype through connecting discernible characteristics with immunological mechanisms. This comprehensive review of the immunology of asthma details the currently known pathophysiology and clinical practice biomarkers in addition to forefront biologic and targeted therapies for all of the asthma endotypes. By understanding the immunology of asthma, practitioners will be able to diagnose patients by asthma endotype and provide personalized, biomarker-driven treatments to effectively control patients' asthma.

Eosinophilic Gastrointestinal Diseases in Children: A Practical Review.

Primary eosinophilic gastrointestinal diseases (EGIDs) represent a heterogeneous group of disorders characterized by eosinophilic inflammation in the absence of known causes for eosinophilia, selectively affecting different segments of the gastrointestinal tract. While pediatric eosinophilic esophagitis (EoE) is a well-defined disease with established guidelines, Eosinophilic Gastritis (EoG), Eosinophilic Gastroenteritis (EoGE) and Eosinophilic Colitis (EoC) remain a clinical enigma with evidence based on limited anecdotal case reports. Large cross-sectional studies in the US defined a prevalence of EoG and EoGE ranging from 1,5 to 6,4/100.000 and from 2,7 to 8,3/100.000 subjects respectively, while the prevalence of EoC ranges from 1,7 to 3,5/100.000 subjects. Regarding the pathogenesis, it is hypothesized that EGIDs result from the interplay between genetic predisposition, intestinal dysbiosis and environmental triggers. Clinically, EGIDs might present with different and nonspecific gastrointestinal symptoms depending on the involved intestinal tract and the extension of eosinophilic inflammatory infiltrate. The diagnosis of EGIDs requires: 1. recurrent gastrointestinal symptoms, 2. increased eosinophils for high power field in biopsy specimens, 3. absence of secondary causes of gastrointestinal eosinophilia. No validated guidelines are available on the clinical management of patients with EGIDs. Evidence from case reports and small uncontrolled case series suggests the use of dietary and corticosteroids as the first-line treatments. Considering the clinical follow-up of EGIDs, three different patterns of disease course are identified: single flare, recurring course-disease and chronic course-disease. This review will focus on pediatric EGIDs distal to esophagus, including Eosinophilic Gastritis (EoG), Eosinophilic Gastroenteritis (EoGE) and Eosinophilic Colitis (EoC).

Serum Levels of Epithelial-Derived Cytokines as Interleukin-25 and Thymic Stromal Lymphopoietin after a Single Dose of Mepolizumab in Patients with Severe Non-Allergic Eosinophilic Asthma: A Short Report.

The bronchial epithelium has continuous contact with environmental agents initiating and maintaining airway type 2 inflammation in asthma. However, there is a lack of data on whether reduced airway eosinophilic inflammation can affect the production of epithelial-derived mediators, such as interleukin-25 (IL-25) and thymic stromal lymphopoietin (TSLP). The aim of this study was to investigate the changes in serum levels of IL-25 and TSLP after a single dose of mepolizumab, a humanized monoclonal antibody to interleukin-5 (IL-5), in patients with severe non-allergic eosinophilic asthma (SNEA). We examined 9 SNEA patients before and four weeks after administration of 100 mg mepolizumab subcutaneously. The fractional exhaled nitric oxide (FeNO) level was analysed using an electrochemical assay (NIOX VERO®, Circassia, UK). Serum IL-25 and TSLP levels were measured by ELISA. Four weeks after the single dose of mepolizumab, blood eosinophil count significantly decreased from 0.55 ± 0.20 × 109/l to 0.14 ± 0.04 × 109/l (p = 0.01) and FEV1 increased from 2.1 ± 0.5 l (65.4 ± 8.8% of predicted) to 2.6 ± 0.4 l (76.4 ± 9.1% of predicted) (p = 0.04), while FeNO level has not changed (32.3 ± 8.4 vs 42.9 ± 12.6 ppb). Serum IL-25 level significantly decreased from 48.0 ± 17.2 pg/mL to 34.8 ± 17.1 pg/mL (p = 0.02) with same tendency in TSLP level: from 359.8 ± 71.3 pg/mL to 275.6 ± 47.8 pg/mL (p = 0.02). It has also been noticed a significant relation between changes in the blood eosinophil count and serum IL-25 level (r = 0.81, p = 0.008), as well as between changes in serum IL-25 and TSLP levels (r = 0.93, p = 0.004) after a single dose of mepolizumab. Thus, anti-IL-5 treatment with mepolizumab might diminish the production of bronchial epithelial-derived cytokines IL-25 and TSLP in patients with SNEA which is potentially related to reduced eosinophilic inflammation. This trial is registered in ClinicalTrial.gov with identifier NCT03388359.

Granulomatosis eosinofílica con poliangeítis y la inhibición de la interleucina 5: ¿el inicio de algo nuevo? / Eosinophilic granulomatosis with polyangiitis and interleukin 5 inhibition: a new beginning?

La granulomatosis eosinofílica con poliangeítis (EGPA) es una vasculitis poco frecuente caracterizada por asma, hipereosinofilia y afectación de distintos órganos. Alrededor del 40% de pacientes tienen un anticuerpo anticitoplasma de neutrófilo (ANCA) positivo. La mejor comprensión de la fisiopatología de la EGPA ha destacado el papel de los eosinófilos y ha abierto un abanico de nuevas dianas terapéuticas. Una de ellas es la interleucina-5 (IL-5) involucrada en la inflamación eosinofílica. En esta revisión describimos las características de la EGPA junto a la evidencia, hasta la fecha publicada, con respecto a la eficacia del mepolizumab (anticuerpo monoclonal dirigido contra la IL-5) en esta patología

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare vasculitis characterized by asthma, hypereosinophilia, and multiorgan involvement. Almost 40% of the patients have positive antineutrophil cytoplasmic antibody (ANCA). Advances in knowledge of the pathophysiology of EGPA have highlighted the key role of eosinophils and opened a range of new therapeutic targets. Interleukin-5 (IL-5) is one of them as it is involved in eosinophilic inflammation. In this review, we describe the features of EGPA and the evidence available today about the efficacy of mepolizumab (an anti-IL-5 monoclonal antibody) in this disease

Disappearance of angina attacks after administration of mepolizumab.

A 75-year-old woman with bronchial asthma and angina presented with dyspnea. She was using nifedipine, nitroglycerin, pranlukast and salmeterol plus fluticasone propionate inhalations. We diagnosed her with severe bronchial asthma. Oral steroids prescribed for the asthma symptoms had only temporary effects. Therefore, we additionally prescribed mepolizumab; the bronchial asthma improved and the angina attacks disappeared. However, after the patient discontinued treatment, the bronchial asthma and angina attacks recurred, which were treated with nitroglycerin. When she returned 12 weeks later, we resumed mepolizumab administration; the bronchial asthma improved and the angina attacks disappeared again. Hence, we concluded that her angina was due to eosinophilia since the angina attacks disappeared with the mepolizumab therapy. Despite limitations such as lack of arterial blood gas data, perfusion scan, gastrointestinal fiberscopy and Aspergillus skin and precipitation tests, we believe that this is the first report to suggest mepolizumab treatment for angina attacks.

Mechanisms of itching in mycosis fungoides: grade of itching correlates with eosinophil infiltration and kallikrein 5 expression.

BACKGROUND: Mycosis fungoides (MF) is the most common variant of cutaneous T-cell lymphomas (CTCL). Itching can be a major symptom for patients with CTCL, however, itching associated with MF is not relieved by conventional therapy using anti-histamines, suggesting that histamine is not the main pruritogen. Therefore, the underlying mechanisms of itching in MF patients remain unclear. OBJECTIVES: To investigate the clinical and histopathological features associated with MF-related itching. MATERIALS AND METHODS: Skin sections from MF patients and healthy subjects were used for pathophysiological analysis and evaluation of protease activity. These results were compared with the degree of itching. RESULTS: Of the MF patients, 40% did not report itching and 60% reported itching (moderate itching: 40%; strong itching: 20%). The number of eosinophils, but not mast cells, that infiltrated into skin was increased in the group with strong itching. In the skin of patients, both serine protease activity and immunoreactivity to kallikrein 5 (KLK5), a known itch mediator, increased relative to the grade of itching. CONCLUSION: These results suggest that KLK5 and eosinophil infiltration may be involved in itching in patients with MF.