Food intolerance and skin prick test in treated and untreated irritable bowel syndrome

AIM： To correlate the clinical features of treated and untreated patients with irritable bowel syndrome （IBS） to the results of skin prick test （SPT） for food and inhalant allergens. METHODS： We recruited 105 subjects to form three different target groups： treated group （n=44） undergoing treatment for IBS, untreated group （n =31） meeting the Rome Ⅱ criteria without treatment for IBS, control group （n = 30） with no IBS symptoms. RESULTS： SPT results were different among the three groups in which SPT was positive in 17 （38.6%） treated patients, in 5 （16.1%） untreated patients and in 1 （3.3%） control （P〈0.01）. The number of positive SPTs was greater in the IBS group than in the control group （P〈 0.001）. The number of positive food SPTs was higher in the treated IBS group than in the untreated IBS group （P= 0.03）. CONCLUSION： Positive food SPT is higher in IBS patients than in controls.

Discrepancies between the responses to skin prick test to food and respiratory antigens in two subtypes of patients with irritable bowel syndrome

AIM:To compare the response to skin prick tests (SPTs) to food antigens (FAs) and inhalant allergens (IAs) in patients with two subtypes of irritable bowel syndrome (IBS) and healthy controls. METHODS:We compared the results of SPTs for IAs and FAs in 87 volunteers divided into three groups:diarrhea predominant IBS (D-IBS) GroupⅠ(n = 19), constipation predominant IBS (C-IBS) Group Ⅱ (n = 17), and normal controls Group Ⅲ (n = 51). RESULTS:Of the 285 tests (171 for FAs and 114 for IAs) performed in GroupⅠwe obtained 45 (26.3%) positive responses for FA and 23 (20.1%) for IA. Of the 153 tests for FA in Group Ⅱ, we obtained 66 (20.1%) positive responses, and of the 102 tests for IA, we obtained 20 (19.6%) positive responses. Of the 459 tests for FA performed in Group Ⅲ, we obtained 39 (84%) positive responses, and of the 306 for IA, we obtained 52 (16.9%) positive responses. The numbers of positive responses were not significantly different between the three groups, but in the D-IBS group, the number of SPTFA responses differed significantly from those for the other two groups (P < 0.01). CONCLUSION:Despite the small number of cases studied, the higher reactivity to FAs in GroupⅠcompared to Groups Ⅱ and Ⅲ adds new information, and suggests the presence of a possible alteration in intestinal epithelial function.

Comparison and Evaluation of Several Dermatophagoides Pteronyssinus Allergen Extracts for Skin Prick Test

Objective To evaluate the significance of several Dermatophagoides pteronyssinus allergen extracts for skin prick test(SPT) in patients allergic to Dermatophagoides pteronyssinus.Methods Two hundred and nineteen patients enrolled in Peking Union Medical College Hospital underwent SPT and serum specific IgE assay to detect the Dermatophagoides pteronyssinus allergen.Three kinds of house dust mite allergen extracts were used for SPT,including the Dermatophagoides pteronyssinus extract prepared by our laboratory(group A),standardized Dermatophagoides pteronyssinus extract(group B),and mixed extracts of Dermatophagoides pteronyssinus and Dermatophagoides farinae(group C).Human serum specific IgE result was regarded as the reference standard for diagnosis of Dermatophagoides pteronyssinus allergy.The receiver operating characteristic(ROC) curve was used to evaluate the diagnostic performance of SPT with the extracts of three groups.Results SPT results showed that the median wheal diameter of group A,group B,and group C was 0.43,0.35,and 0.28 cm,respectively,with significant difference among three groups(P<0.05).The difference was significant between group A and B(P<0.01) as well as group A and C(P<0.01),but not between group B and C(P>0.05).There was no local urticaria or systemic allergic reactions following the procedure of SPT.Local reaction was observed in 5 patients and delayed reaction was in 2 patients of group A.As for group B and C,local reaction occurred in 3 cases and delayed reaction in 2 cases in each group.The area under ROC curve of SPT with extract in group A,group B,and group C was 0.765,0.801,and 0.782,respectively.Based on the detection results of serum specific IgE,the sensitivity of SPT in diagnosis of Dermato-phagoides pteronyssinus allergy with extract of group A,group B,and group C was 92.4%,87.0%,and 81.5%,and the specificity was 60.6%,73.2%,and 74.8%,respectively.Conclusion The Dermatophagoides pteronyssinus extract for SPT prepared by our laboratory offers good sensitivity and specificity comparable to commercially available allergen extracts,and it may be an appropriate candidate for clinical screening and diagnosis of Dermatophagoides pteronyssinus allergy.

Effectiveness of Virtual Reality for Pediatric Pain and Anxiety Management during Skin Prick Testing

This study investigated the effectiveness of virtual reality (VR) distraction, compared to comic book distraction and no distraction, in reducing pain and anxiety during a medical procedure in a pediatric population: the skin prick test. Although this test has many advantages and is considered to be minimally invasive, it causes anxiety and painful discomfort in children. Ninety-two children aged 7 to 17 years consulting for an allergic test received VR distraction, comic book distraction, or no distraction. Outcome measures included pain score, level of anxiety, and VR measures. The results showed that there were no significant differences between the three groups regarding sex, age, and preprocedural anxiety level. In the distraction groups (VR and comic book), children reported significantly lower pain and procedural anxiety scores than children with no distraction;VR distraction had a more significant effect than comic book distraction. A decrease in anxiety before and during the skin prick test is significantly more significant in VR distraction. This study suggested the effectiveness and feasibility of VR to reduce pain and anxiety during the pediatric skin prick test.

Diagnostic accuracy and safety of Dermatophagoides pteronyssinus extracts used for skin prick test

Background:Dermatophagoides pteronyssinus is a common allergen causing allergic diseases in China.The aim of this study was to evaluate the efficacy and safety of D.pteronyssinus extracts produced by Peking Union Medical College Hospital(PUMCH)for the skin prick test(SPT)in the diagnosis of D.pteronyssinus allergy.Methods:A total of 910 subjects with allergic diseases were prescribed D.pteronyssinus SPT and specific sIgE(sIgE)test among the Outpatients of Department of Allergy,PUMCH from August 10,2015 to August 30,2017.Receiver operating characteristic curve(ROC)analysis was performed according to the results of D.pteronyssinus-sIgE detection.The accuracy of D.pteronyssinus extracts used for SPT in the diagnosis of D.pteronyssinus allergy was evaluated under different cutoff values.Adverse events after SPT were recorded to evaluate safety.Results:There were 796 and 618 subjects in the full analysis set(FAS)and the per protocol set(PPS),respectively.The areas under the curve of FAS and PPS were 0.871 and 0.873,respectively.According to the ROC of PPS,the optimal and 95%specificity diagnostic cutoff values of D.pteronyssinus SPT mean wheal diameter were 3.25 and 3.75 mm,respectively.No adverse events occurred.Conclusion:The extracts of D.pteronyssinus for SPT were simple,highly accurate,and safe and should be considered for recommendation in the clinical diagnosis of D.pteronyssinus allergy.

A fifteen-year review of skin allergy testing in Irish patients with symptomatic rhinitis

Objective:Our objective was to review skin prick allergy testing(SPAT)results in patients with symptomatic rhinitis in an Irish population.Methods:A fifteen-year retrospective review of our database of symptomatic patients with rhinitis was performed.All patients who had SPAT performed during this interval were included.Data was analysed in terms of demographics and dominant allergens.Results:1158 patients were included.617 Females vs 541 Males.Age range five to eighty-five years old.Mean age thirty-four years.49%of our patients tested positive to at least one aeroallergen.The most common allergens were dust mites(23%)and timothy grass(22%).Patients born during the Irish pollen season(April-July)were between 5 and 7 times more likely to be sensitive to timothy and ryegrass pollens compared to others tested.241 patients had both SPAT and serum allergen specific IgE testing(SASIgET)performed;positive results were consistent between both groups.Conclusion:Results demonstrated that half of our patients with symptomatic rhinitis had allergen sensitisation.Dust mites and grass were the main allergens in our area.Our nurse led clinic has allowed efficient patient education and the development of a unique Irish SPAT database.Retesting a patient with a known allergy test result it is not indicated.

Evaluation of serum specific IgE for the diagnosis of allergic rhinitis with multi-allergens

Background Objective evaluation of allergic rhinitis （AR） requires in vivo and in vitro tests. In vitro tests are important to assist or ensure the main allergens in multi-allergen-sensitive patients. The aim of this study was to evaluate the utility of serum specific IgE （slgE） in the diagnosis of AR patients with multi-allergens in the Chinese population.Methods Combining a positive skin prick test （SPT） and clinical history as the diagnostic reference criteria of AR, we estimated concentrations of slgE produced in response to the 7 most frequent allergens among 85 AR patients, using the UniCAP assay system.Results Among 85 individuals with positive SPT results and allergen-specific nasal symptoms, slgE concentration correlated well with SPT classes among all the tested allergens. Based on a clinical diagnosis and SPT results using a positive cut-off value of a class 1 score, the CAP test performed well and the sensitivity for different allergens ranged from 0.5 （giant ragweed） to 0.91 （Dermatophagoides pteronyssinus （Der p） and Dermatophagoides farinae （Der f）, while specificity ranged from 0.93 （Der f） to 1.0 （animal hair, Derp and mugwort）. When the cut-off score was adjusted to class 2, the sensitivity showed an increase overall while the remaining assessed items, including specificity, positive predictive value, negative predictive value and efficiency, showed an unacceptable decline.Conclusions Well-established serum slgE tests correlated well with SPTs. Setting a class 1 cut-off for positivity of SPT results was better than a class 2 setting for assessing the AR diagnostic value.