Incidence of food anaphylaxis in Piemonte region (Italy): data from registry of Center for Severe Allergic Reactions.

There are wide differences in estimated incidence and prevalence of anaphylaxis because of the absence, until recently, of a universal consensus on the definition of anaphylaxis and the different source of collected data. We aimed to estimate the incidence of food anaphylaxis based on the database of Piemonte Region (Italy) Reference Center for Severe Allergic Reactions. All cases of severe food allergic reactions reported in 2010 were studied. Clinical data associated to the reports were evaluated according to National Institute of Allergy and Infectious Disease and Food Allergy and Anaphylaxis Network diagnostic criteria of anaphylaxis. 75 % of the 778 cases were classified as food anaphylaxis (incidence of 13/100,000 person-years, ranging from 9.9 in adults to 29/100,000 person-years in children). Nuts were the most frequent foods causing anaphylaxis. Milk and eggs were responsible for anaphylaxis more often in children, while peach, vegetables and crustaceans were in adults. Cardiovascular symptoms were more frequent in adults. Gastrointestinal involvement was more frequent in children. A high prevalence of respiratory allergic comorbidities was observed. Food is an important cause of anaphylaxis, particularly in subjects with respiratory allergic comorbidities. Children and adults differ in triggers and clinical presentation of anaphylaxis.

Innate and lymphocytic response of birch-allergic patients before and after sublingual immunotherapy.

Functional imbalance in Th1/Th2 cell response toward allergens is a recognized hallmark of allergic patients and a major role of dendritic cells (DCs) in redirecting T-cell phenotypes after specific immunotherapy has been suggested. This study investigates the proliferative and cytokine responses of T cells cocultured with monocyte-derived DCs (MoDCs) after allergen stimulation in birch-allergic patients compared with controls and investigates whether sublingual immunotherapy (SLIT) could change the DC-driven immune response. T cells were stimulated with the major birch pollen allergen (nBet v1) and MoDCs from eight birch-allergic patients with seasonal allergic rhinitis and eight nonallergic controls. Proliferation and cytokine production were measured before and after one course of SLIT with birch allergoid. Significantly lower levels of proinflammatory (IL-1beta, p = 0.027; IL-6, p = 0.030; TNF-alpha, p = 0.019) and Th1 (interferon gamma, p = 0.032; IL-12, p = 0.05) cytokines were measured in supernatants of T cells and MoDCs cultures from allergic patients compared with nonallergic controls. After SLIT, significant increase in IL-12 (p = 0.039), IL-1beta (p = 0.040), IL-6 (p = 0.041), TNF-α (p = 0.048), and IL-10 (p = 0.048) and significant decrease in IL-13 (p = 0.001) were observed. MoDCs/T-cell cocultures, pulsed with the specific allergen, produced lower quantities of proinflammatory and Th1 cytokines in allergic patients compared with healthy subjects, suggesting an allergen-specific impairment of natural immunity and Th1 immune response. A single course of SLIT was able to enhance allergen-specific innate immunity and to modify lymphocyte response, promoting Th1 and T-cell regulatory activity.

Chronic cough and irritable larynx.

BACKGROUND: Perennial rhinitis (PR), chronic rhinosinusitis (CRS), or both, asthma, and gastroesophageal reflux disease (GERD) are the most frequent triggers of chronic cough (CC). Extrathoracic airway receptors might be involved in all 3 conditions because asthma is often associated with PR/CRS and gastroesophageal refluxate might reach the upper airway. We previously found that most patients with rhinosinusitis, postnasal drip, and pharyngolaryngitis show laryngeal hyperresponsiveness (LHR; ie, vocal cord adduction on histamine challenge) that is consistent with an irritable larynx. OBJECTIVE: We sought to evaluate the role of LHR in patients with CC. METHODS: LHR and bronchial hyperresponsiveness (BHR) to histamine were assessed in 372 patients with CC and in 52 asthmatic control subjects without cough (asthma/CC-). In 172 patients the challenge was repeated after treatment for the underlying cause of cough. RESULTS: The primary trigger of CC was PR/CRS in 208 (56%) patients, asthma in 41 (11%) patients (asthma/CC+), GERD in 62 (17%) patients, and unexplained chronic cough (UNEX) in 61 (16%) patients. LHR prevalence was 76% in patients with PR/CRS, 77% in patients with GERD, 66% in patients with UNEX, 93% in asthma/CC+ patients, and 11% in asthma/CC- patients. Upper airway disease was found in most (95%) asthma/CC+ patients and in 6% of asthma/CC- patients. BHR discriminated asthmatic patients and atopy discriminated patients with PR/CRS from patients with GERD and UNEX. Absence of LHR discriminated asthmatic patients without cough. After treatment, LHR resolved in 63% of the patients and improved in 11%, and BHR resolved in 57% and improved in 18%. CONCLUSIONS: An irritable larynx is common in patients with CC and indicates upper airway involvement, whether from rhinitis/sinusitis, gastric reflux, or idiopathic sensory neuropathy.

Increased oral nitric oxide in obstructive sleep apnoea.

BACKGROUND: Hypoxia and snoring-related mechanical trauma contribute to airway inflammation in obstructive sleep apnoea (OSA). Increased exhaled nitric oxide (FENO), an airway inflammation marker, has been reported in OSA patients. We propose the measure of NO in the oral cavity (oNO) as marker of oropharyngeal inflammation in OSA. METHODS: We compared oNO and FENO of 39 OSA patients with those of 26 mild asthmatics (ASTHMA), 15 patients with chronic rhinitis or rhinosinusitis (CRS) and 24 healthy subjects. A special device was used for oNO measurement. Apnoea/hypopnoea index (AHI), oxygen desaturation index, mean and nadir SaO2 were calculated from the polysomnography. RESULTS: oNO was significantly increased in OSA (104.2 95%CI 80.2-135.5ppb) as compared to ASTHMA (71.9 95%CI 56.3-91.9ppb; p=0.015), CRS (54.4 95%CI 40.2-73.7ppb; p=0.009) and healthy subjects (63.6 95%CI 59-73ppb; p<0.001). oNO was directly related to AHI (r=0.466, p=0.003) and to minutes slept with SaO2 <90% (r=0.471, p=0.011) and it was inversely related to nadirSaO2 (r=-0.393, p=0.018). FENO was highest in asthmatics (40.3 95%CI 32.5-50.1ppb) and only slightly elevated in OSA (23.1 95%CI 19,8-28.3ppb) and CRS (22.8 95%CI 16.8-32.5ppb). CONCLUSIONS: The finding that oral NO is increased in OSA and is related to upper airway obstructive episodes and to hypoxemia severity, strengthens the clinical and pathogenic role of oral inflammation in OSA.

Effect of arterial hypertension on chronic urticaria duration.

BACKGROUND: Reliable clinical or laboratory markers of chronic idiopathic urticaria (CIU) duration are not available. Angioedema, autologous serum skin test (ASST) results, and antithyroid antibodies have been inconsistently associated with longer urticaria duration. OBJECTIVE: To investigate the association of clinical and laboratory parameters with CIU duration, including systemic hypertension, because activation of the coagulation cascade pathway may contribute to the pathogenesis of CIU. METHODS: We performed a prospective study of a cohort of 228 consecutive adult patients with CIU of moderate to severe intensity referred to 2 outpatient allergy clinics and followed up for a 3- to 5-year period. The association of clinical and laboratory parameters (sex, atopy, markers of autoimmunity, antithyroid antibodies, positive ASST result, Helicobacter pylori infection, and hypertension) with urticaria duration was analyzed using semiparametric multivariable proportional hazards models (Cox regression) using remission as main outcome measure. RESULTS: Apart from systemic hypertension (hazard ratio, 0.71; 95% confidence interval, 0.53-0.95; P = .02), none of the considered parameters influenced CIU remission of our patients; 74% and 54% of our patients with and without hypertension, respectively, still had CIU after 5 years. CONCLUSIONS: Our results show, for the first time to our knowledge, that hypertension is associated with extended duration of CIU. This observation, together with the previous findings that point to vascular and coagulation involvement in CIU, may suggest a new approach to antihistamine-refractory CIU treatment, including adequate treatment of hypertension.