Sabrina Mietta

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.

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.

Italian study on buckwheat allergy: prevalence and clinical features of buckwheat-sensitized patients in Italy

Buckwheat allergy is considered a rare food allergy outside of Asia. In Europe, buckwheat has been described mainly as a hidden allergen. Data on the prevalence of buckwheat hypersensitivity in non-Asian countries is very poor. The aim of this multicenter study was to evaluate the prevalence of buckwheat sensitization and its association with other sensitizations among patients referred to allergy clinics in different geographic areas of Italy. All patients referred to 18 Italian allergy clinics from February through April 2011 were included in the study and evaluated for sensitization to buckwheat and other allergens depending on their clinical history. A total of 1,954 patients were included in the study and 61.3% of them were atopic. Mean prevalence of buckwheat sensitization was 3.6% with significant difference between Northern (4.5%), Central (2.2%) and Southern (2.8%) regions. This is, to our knowledge, the largest epidemiological survey on buckwheat allergy reported outside of Asia. Buckwheat is an emerging allergen in Italy, being more frequently associated to sensitization in Northern regions.

Anaphylaxis after application of topical bacitracin-neomycin powder

FEV1 but also DN2 (correlation coefficients: 0.575 vs 0.367), indicating that the correlation was stronger with central airway obstruction thanwith peripheral ventilation inhomogeneity.4 These findings suggest that R5-R20 is not a parameter specific to peripheral airways but one to central airways instead. Further studies are needed to clarify the meaning of R5-R20 and to establish the interpretation of forced oscillatory parameters in asthma.

The "nocebo effect" in drug hypersensitivity diagnosis

Background Placebo-controlled oral drug provocation tests (DPTs) are an important step in drug hypersensitivity diagnosis. Administration of placebo (an inert sostance not detectable from drug) is recommended to avoid psychological influences on the interpretation of DPT results, however actually little is known about how to deal a reaction to placebo and how to go further with the diagnostic procedures.

Food anaphylaxis: data from registry of Center for Severe Allergic Reactions of Piemonte region (Italy)

Results Among the 1315 reported cases of anaphylaxis, 541 could be classified as food anaphylaxis, with level 1 (38%), level 2 (59%), and level 3 (3%) of probability. 212 patients were children (< 18yrs, age 7.4±5.4 yrs, M/ F=2.0), and 329 were adults (age 35.5±12.9 yrs, M/F= 0.5). The main implicated food allergens were nuts (31%), egg (16%), milk (15%), fish (8%) and sesame (7%) in children and nuts (26%), vegetables (14%), crustaceans (12%), fresh fruit (10%), fish (7%), legumes (6%), seeds (6%) and flours (5%) in adults. Food-dependent exercise-induced anaphylaxis was reported in 28 patients. Skin and respiratory symptoms were reported respectively in 95% and 81% patients, with no differences between children and adults, while gastrointestinal symptoms were more frequent in children (43 vs 29%, p=0.001) and cardiovascular involvement was more frequent in adults (36 vs 16%, p<0.0001).