BACKGROUND: Measurement of the exhaled nitric oxide fraction (FeNO) has been proposed as an indirect and non-invasive method to detect eosinophilic airway inflammation. Allergic rhinitis (AR) is frequently associated with high levels of FeNO. Allergic sensitization can contribute to the recruitment of eosinophils in the airway and the consequent increase in FeNO.
OBJECTIVE: To correlate FeNO values with inflammatory and atopic sensitization biomarkers in patients with AR.
METHODS: Observational, analytical, cross-sectional study. Children and adolescents with AR without asthma were included. FeNO, blood eosinophil count, total serum IgE were determined and skin tests with aeroallergens were performed by calculating the scores for PPC1 (number of positive allergens), STS2 (sum of millimeters of positive papules) and the atopy index (ratio between STS2/STS1). Spearman\'s correlation test was used between FeNO and variables of inflammation and atopy.
RESULTS: Twenty-eight patients between 6 and 17 years old were included. There was a significant positive correlation between FeNO and blood eosinophils (r=.38; p=.047) and between FeNO and the atopy index (r=.40; p=.03). No correlation was found between FeNO and total serum IgE (r=.24; p=.21), STS1 (r=.20; p=.32) and STS2 (r=.34; p=.08).
CONCLUSIONS: In children and adolescents with AR, FeNO was correlated with the atopy index and the blood eosinophil count. These last biomarkers could be used as alternatives for FeNO as biomarkers of lower airway inflammation in patients with AR.

OBJECTIVE: Chronic nodular prurigo (CNPG) is a recently defined and currently underdiagnosed disease with a variety of causes. It is associated with multiple comorbidities, and its management and treatment have improved with a better understanding of its pathogenesis. The aim of this study was to describe our experience with a series of patients with CNPG.
METHODS: Single-center, observational, retrospective study of the sociodemographic and clinical characteristics of patients with CNPG seen at the dermatology department of a tertiary care hospital between 2009 and 2021.
RESULTS: We included 74 patients, mostly women (63.5%), with a mean age of 57 years. Overall, 39.2% of patients had a concomitant skin condition, mainly atopic dermatitis (62%). Other comorbidities included endocrine disorders (54.1%), cardiovascular disease (44.4%), and psychiatric disorders (36.5%). Skin biopsy helped confirm the clinical diagnosis in 70% of cases. The mean immunoglobulin E level was higher than normal (516IU/mL), regardless of atopic predisposition. On average, patients received three treatments, the most common choices being methotrexate, antihistamines, and topical and oral corticosteroids. Methotrexate was among the most effective options.
CONCLUSIONS: CNPG is a complex disease associated with multiple comorbidities. It requires a multidisciplinary approach, with the dermatologist at the center. Classical treatment approaches are probably insufficient.

OBJECTIVE: Chronic nodular prurigo (CNPG) is a recently defined and currently underdiagnosed disease with a variety of causes. It is associated with multiple comorbidities, and its management and treatment have improved with a better understanding of its pathogenesis. The aim of this study was to describe our experience with a series of patients with CNPG.
METHODS: Single-center, observational, retrospective study of the sociodemographic and clinical characteristics of patients with CNPG seen at the dermatology department of a tertiary care hospital between 2009 and 2021.
RESULTS: We included 74 patients, mostly women (63.5%), with a mean age of 57 years. Overall, 39.2% of patients had a concomitant skin condition, mainly atopic dermatitis (62%). Other comorbidities included endocrine disorders (54.1%), cardiovascular disease (44.4%), and psychiatric disorders (36.5%). Skin biopsy helped confirm the clinical diagnosis in 70% of cases. The mean immunoglobulin E level was higher than normal (516 IU/mL), regardless of atopic predisposition. On average, patients received 3 treatments, the most common choices being methotrexate, antihistamines, and topical and oral corticosteroids. Methotrexate was among the most effective options.
CONCLUSIONS: CNPG is a complex disease associated with multiple comorbidities. It requires a multidisciplinary approach, with the dermatologist at the center. Classical treatment approaches are probably insufficient.

The association of moderate to severe eczema and elevated plasma levels of immunoglobulin E is a characteristic not only of atopic dermatitis but also of various genodermatoses: hyperimmunoglobulin E syndromes, Omenn syndrome, Netherton syndrome, peeling skin syndrome type B, severe dermatitis, multiple allergies, and metabolic wasting syndrome, Wiskott-Aldrich syndrome, prolidase deficiency, Loeys-Dietz syndrome, IPEX syndrome, STAT5B deficiency, and pentasomy X. The clinical presentation of these genodermatoses -typically in children- is consistent with severe atopic dermatitis. Immunoglobulin E is elevated from birth and response to conventional treatments is poor. Diagnosis is further complicated by the fact that these genodermatoses often share other clinical manifestations and laboratory findings. We present practical guidelines for differentiating among these various entities, with the aim of helping physicians decide what type of genetic test should be carried out -and when- in order to establish a definitive diagnosis.

BACKGROUND: The aim of the study was to assess the use of faecal calprotectin (FCP) in infants with signs and symptoms of non-IgE-mediated cow\'s milk protein allergy (CMA) for both diagnosis and prediction of clinical response at the time of withdrawal of milk proteins.
METHODS: A one year prospective study was conducted on 82 infants between 1 and 12 months of age in the Eastern area of Málaga-Axarquía, of whom 40 of them had been diagnosed with non-IgE-mediated CMA (with suggestive symptoms and positive response to milk withdrawal), 12 not diagnosed with CMA, and 30 of them were the control group. FCP was measured at three different times: time of diagnosis, and one and three months later. ANOVA for repeated measures, nominal logistic regression and ROC curves were prepared using the SPSS.20 package and Medcalc.
RESULTS: Differences between diagnostic and control groups were assessed: there was a statistically significant relationship (p<.0001) between high FCP levels and infants suffering CMA, as well as the levels at time of diagnosis, 1 and 3 months (p <.001). A ROC curve was constructed between FCP levels and diagnosis of CMA, with 138 ug/g, with the best cut-off being with an area under the curve of 0.89. However, it is only 0.68 to predict a clinical response.
CONCLUSIONS: FCP levels lower than 138ug/g could be useful to rule out non-IgE-mediated CMA diagnosis. Calprotectin is not a good test to predict clinical response to milk withdrawal.