Mollusk allergy in shrimp-allergic patients: Still a complex diagnosis. An Italian real-life cross-sectional multicenter study.

Introduction: Shellfish allergy is an important cause of food allergies worldwide. Both in vivo and in vitro diagnostics failure nowadays is caused by the poor quality of the extracts associated with the scarce availability of allergenic molecules in the market. It is known that not all patients with shellfish allergies experience adverse reactions to mollusks. It is still unclear how to detect and diagnose these patients correctly. Aim: To investigate the features of shrimp-allergic patients either reactive or tolerant to mollusks, with the currently available diagnostic methods. Methods: Nineteen centers, scattered throughout Italy, participated in the real-life study, enrolling patients allergic to shrimp with or without associated reactions to mollusks. Patients underwent skin tests using commercial extracts or fresh raw and cooked shrimp and mollusks, and IgE reactivity to currently available allergenic extracts and molecules was measured in vitro. Results: Two hundred and forty-seven individuals with a self reported adverse reactions to shrimp participated in the study; of these 47.8% reported an adverse reaction to mollusks ingestion (cephalopod and/or bivalve). Neither of the tests used, in vivo nor in vitro, was able to detect all selected patients. Accordingly, a great heterogeneity of results was observed: in vivo and in vitro tests agreed in 52% and 62% of cases. Skin tests were able to identify the mollusk reactors (p < 0.001), also using fresh cooked or raw food (p < 0.001). The reactivity profile of mollusk reactors was dominated by Pen m 1, over Pen m 2 and Pen m 4 compared to tolerant subjects, but 33% of patients were not detected by any of the available molecules. Overall, a higher frequency of IgE rectivity to shrimp was recorded in northern Italy, while mollusk reactivity was more frequent in the center-south. Conclusion: The current diagnostic methods are inadequate to predict the cross-reactivity between crustaceans and mollusks. The detection of mollusks hypersensitivity should still rely on skin tests with fresh material. The exclusion of mollusks from shrimp allergic patients' diets should occur when clinical history, available diagnostic instruments, and/or tolerance tests support such a decision.

A qualitative and quantitative comparison of IgE antibody profiles with two multiplex platforms for component-resolved diagnostics in allergic patients.

BACKGROUND: Clinically complex phenotypes require more and more sophisticated and comprehensive diagnostic approaches, able to discriminate genuine sensitizations from cross-reactivity. Interpretative complexity of multiplex diagnostic arrays has somewhat limited their diffusion. This study compares two currently available methods, namely ISAC® test and ALEX2® test. METHODS: In total, 140 allergic individuals, with a history of atopic dermatitis, adverse food reactions, allergic rhinitis and/or bronchial asthma were studied by Allergy Explorer-ALEX2® macroarray and ImmunoCAP ISAC112® . Lin's concordance correlation coefficient, intraclass correlation coefficient and Bland-Altman plots were used to verify the agreement between continuous values. Cohen's kappa coefficient (k) was assessed for the molecules available in both tests. The degree of relationship was analysed using Spearman's correlation (quantitative variables) and Pearson's χ2 or Fisher's exact test (categorical variables). RESULTS: A substantial agreement (κ = 0.795) was observed between the two methods with 94,3% concordant results when results were dichotomized as negative or positive, but if double-negative results were discarded, the agreement dropped to 71%. Conversely, little or no concordance was observed comparing raw data. Considering the 102 molecules shared by both systems, 28/102 (27%) showed an almost perfect agreement (k > 0.81), and concordance was good (k > 0.61) in a further 32 (31%) cases. A perfect to substantial agreement was observed by comparing species-specific aeroallergens. Heterogeneous results emerged comparing panallergens (co-recognition ranging from 30% for tropomyosin/serum albumins to 70% for PR-10/profilin). The correlation among LTP, profilin and PR-10 assayed with ISAC® was better than ALEX2® , but the latter identified more positive cases due to the wider number of molecules available. The CCD blocker provided by ALEX® test abolishes the carbohydrate determinants signal in 60% of the 33 cases reactive to MUXF3 on the ISAC® test. CONCLUSION: Despite the excellent concordance of the species-specific markers, the analysis of the panallergens provided in both methods suggests a better performance of the ISAC® test on those components, while the ALEX2® test, which includes a larger number of allergens, allowing a broader molecular detection.

May Bacterial Infections Trigger Bullous Pemphigoid? Case Report and Review of Literature.

Bullous pemphigoid (BP) is an autoimmune blistering skin disease, mainly observed in the elderly. Infections have been suggested as possible disease triggers. However, infections may even heavily influence the disease clinical course and mortality. A 75-year-old woman was admitted to hospital for severe erythematosus blistering disease, accompanied by hyper-eosinophilia and hyper-IgE. The culture of bullous fluid was positive for Enterococcus faecalis, the blood culture was positive for Staphylococcus aureus, and the urine culture was positive for Proteus mirabilis and Escherichia coli. Moreover, circulating anti-BP180 IgG was present and the histopathological/ultrastructural examination of a lesional skin biopsy was compatible with BP. High eosinophil levels (up to 3170/µL) were found throughout the clinical course, while values below 1000/µL were associated with clinical improvement. The total IgE was 1273 IU/mL, and specific anti-G/V-penicillin/ampicillin IgE antibodies were positive. The patient had a complete clinical recovery in two months with methyl-prednisolone (40 then 20 mg/day) and low-dose azathioprine (50 mg/day) as a steroid-sparing agent. The steroid treatment was tapered until interruption during a one-year period and intravenous immunoglobulins have been administered for three years in order for azathioprine to also be interrupted. The patient stopped any treatment five years ago and, in this period, has always been in good health. In this case, the contemporaneous onset of different bacterial infections and BP is suggestive of bacterial infections acting as BP trigger(s), with allergic and autoimmune pathways contributing to the disease pathogenesis.

Validation study of a new chemiluminescent singleplex IgE assay in a set of Italian allergic rhinitis patients.

BACKGROUND: The measurement of specific IgE to allergenic extracts and molecules in patients with allergic rhinitis (AR) is crucial for a precise diagnosis and further immunotherapy. Companies providing in vitro diagnostic methods in allergology continuously strive for the optimization and modernization of such methods. A new generation of automated allergy tests based on chemiluminescence detection and paramagnetic microparticles is now available, with possible advantages in sample volume, cost-effectiveness and avoidance of sample-related interference. OBJECTIVES: To test whether sIgE antibody levels obtained with a new singleplex chemiluminescent method have a good agreement with the corresponding results obtained with a "gold standard" test. METHODS: We tested sera from 368 AR patients. Specific IgE sera levels (kU/L) to a comprehensive panel of 15 allergen extracts and 6 molecules were tested with ImmunoCAP® (Thermo Fisher Scientific Inc, Phadia AB, Uppsala, Sweden) and NOVEOS™ (HYCOR® Biomedical, Garden Grove, CA, USA). We evaluated the qualitative and quantitative performance of the new NOVEOS system in matching the outcome of ImmunoCAP to each of the examined allergens. RESULTS: In relation to ImmunoCAP, the overall diagnostic sensitivity and specificity of sIgE tests with NOVEOS were 90.8% (95% CI = 88.6-92.7) and 96.2% (95% CI = 93.9-97.8), respectively. These values were higher when only molecules were considered (sensitivity = 98.7% [95% CI = 96.4%-99.7%]; specificity = 94.2% [95% CI = 88.4%-97.6%]) and lower when only extracts were considered (sensitivity = 87.6% [95% CI = 84.7%-90.2%]; specificity = 97% [95% CI = 94.4%-98.6%]). Spearman's correlation between the data set of both methods for a ≥ 0.1 kU/L cut-off was 0.84 (p < .001). CONCLUSIONS: The new singleplex NOVEOS system presented good results for qualitative and quantitative comparisons when testing specific serum IgE antibodies against a range of 21 allergens. This novel immunoassay system using only 4 µl of sample per test appears to be robust and reliable and can, therefore, be used as an aid in allergy diagnosis.

Impact of Mediterranean Diet on Disease Activity and Gut Microbiota Composition of Rheumatoid Arthritis Patients.

Rheumatoid arthritis (RA) is an autoimmune disorder in which gut and oral microbiota play a crucial role. Diet is a modifiable factor that can influence both microbiota composition and arthritis outcome; previous studies have suggested associations between dietary habits and RA, with contrasting results. We investigate the protective effect of the Mediterranean diet (MD) on disease activity and the gut microbiota profile in RA patients. Sixty consecutive RA patients were enrolled upon filling a validated 14-item questionnaire for the assessment of adherence to the Mediterranean diet (Prevention with Mediterranean Diet-PREDIMED). Then, 16S analysis was employed to explore the gut microbiota within the two cohorts of patients. Patients with high adherence to MD (20) had a significantly lower C-reactive protein (p < 0.037) and disease activity (p < 0.034) than the 40 patients with low/moderate adherence to MD. An inverse association between MD and disease activity was confirmed by multivariate analysis after adjustments for all the different demographic, clinical and serologic variables. A healthier gut microbiota composition was observed in the high adherence group, with a significant decrease in Lactobacillaceae and an almost complete absence of Prevotella copri with respect to the low/moderate adherence group. In conclusion, our findings support the protective role of MD on disease activity and microbiota composition in RA patients, and suggest the feasibility of shifting the habitual diet to modulate the gut microbiota and promote the benefits associated with MD.

ß-1,3-glucanase rOle e 9 and MnSOD rAsp f 6 IgE reactivity are the signature of atopic dermatitis in the Mediterranean area.

BACKGROUND: Atopic dermatitis (AD) represents a chronic skin disorder seriously affecting patients' QoL and is often associated with immunological imbalance, disorders of the skin barrier function and environmental factors. OBJECTIVE: We extensively studied the proteomic IgE sensitization profile in a large AD Mediterranean cohort. METHODS: A total of 588 individuals with moderate-severe (70.6%) or mild and/or history of (29.4%) AD were evaluated in comparison to 1285 unselected atopic controls (AC) with a history of adverse reactions to foods, allergic rhinitis and/or bronchial asthma by means of ImmunoCAP ISAC112 ® and Allergy Explorer-ALEX® microarray analysis. RESULTS: The olive tree pollen ß-1,3-glucanase rOle e 9 and the manganese superoxide dismutase from Aspergillus rAsp f 6 were the molecules most significantly associated with AD occurrence and allowed to discriminate among the moderate and severe forms of disease. An IgE hyper-reactivity to cypress, grasses, olive tree, house dust mites (including rDer p 11), and to all cross-reactive components except profilin and polcalcin was observed. About 60% of adults with severe AD were sensitized to nsLTPs. Cross-reactive carbohydrate determinants (CCDs) IgE was found in about one-third of AD participants. Hen eggs nGal d 1 IgE sensitization was more prevalent in the paediatric population, whilst rAsp f 6 and rOle e 9 reactivity was found particularly in older patients. Despite the status of widespread IgE sensitization to both environmental and food allergens, a reduced frequency of patient-reported severe reactions to food or of asthma was observed in AD patients compared to AC, particularly in case of concomitant Ole e 9 reactivity. CONCLUSION AND CLINICAL RELEVANCE: Testing IgE reactivity to a large panel of molecular components unveils important associations between IgE reactivity profiles and AD clinical presentation, highlights the allergens useful for a precise AD signature and allows the detection of interesting sensitisations patterns.

Anti-polysaccharide and anti-diphtheria protective antibodies after 13-valent pneumococcal conjugate vaccination in rheumatoid arthritis patients under immunosuppressive therapy.

Immunogenicity of 13-valent pneumococcal polysaccharide (PnPS) conjugate vaccine (PCV13) was evaluated in 38 rheumatoid arthritis patients under immunosuppressive treatment and 20 healthy controls (HC). Antibodies to all PnPS and diphtheria-toxin analogue conjugate protein were measured pre- (T0), 1 (T1), 6 (T2), 12 (T3) months post-immunization. Patients and HC had similar response to individual PnPS. Mean antibody levels to all PnPS but one doubled at T1 compared with T0, with T3 persistence for only 8-7/13 PnPS. Baseline antibody levels was inversely associated with the rate of responders at T1 (T1/T0≥2) to 11/13 PnPS. Few subjects reached protective IgG levels against some serotypes frequently isolated in Italian patients with invasive pneumococcal disease. Antibody response was not influenced by therapy, except the one to PS7F, which was reduced by tumor necrosis factor-α-inhibitors. Vaccination increased also anti-diphtheria IgG. Despite this study substantially confirmed the PCV13 immunogenicity in immunocompromised patients, it also revealed some limitations.

Ultrasound detection of subclinical synovitis in rheumatoid arthritis patients in clinical remission: a new reduced-joint assessment in 3 target joints.

OBJECTIVES: The ability of ultrasound (US) to identify subclinical joint inflammation in rheumatoid arthritis (RA) patients in remission has been already reported. Nonetheless, current studies present a lack of homogeneity in patient's characteristics and number of joints assessed by US. The aim of this study was to identify a reduced set of target joints to be scanned in RA patients in clinical remission in order to detect subclinical synovitis. METHODS: Forty RA patients in clinical remission (DAS28 ≤2.6) for at least 3 months underwent an US examination of 18 joints: wrist, II-III-IV-V metacarpophalangeal (MCP) and II-III-IV-V metatarsophalangeal joints bilaterally. The presence of synovial hypertrophy (SH) and power-Doppler (PD) signal was registered following the OMERACT definitions and was graded according to a 4-point scale (0-3). Then, by applying a process of data reduction based on the frequency of joint involvement, a reduced assessment was obtained. RESULTS: Twenty (50%) subjects had at least one joint affected by active synovitis; 17.5% presented grade 1 PD and 32.5% grade 2 PD. The joints most frequently affected by active synovitis were the wrists (75%) and the II MCP joints (55%). After data reduction, the evaluation of 3 joints (both wrists and the II MCP of the dominant hand) obtained a sensitivity of 90% for the detection of subclinical synovitis. CONCLUSIONS: The US scan of 3 target joints showed a high sensitivity in detecting subclinical active synovitis in RA patients in clinical remission and can be feasible in the routine assessment of these patients.

Aedes communis Reactivity Is Associated with Bee Venom Hypersensitivity: An in vitro and in vivo Study.

Mosquito bite is usually followed by a local reaction, but severe or systemic reaction may, in rare cases, occur. Allergic reactions to Aedes communis (Ac) may be underestimated due to the lack of reliable diagnostic tools. In this multicenter study, 205 individuals reporting large local reactions to Ac were enrolled and studied for cutaneous or IgE reactivity to Ac, Blattella germanica, Penaeus monodon, and Dermatophagoides pteronyssinus. Extract and molecular IgE reactivity to bees, wasps, hornets, and yellow jacket venoms were also studied in 119 patients with a clinical history of adverse reaction to Hymenoptera. Immunoblot (IB) analysis and immunoCAP IgE inhibition experiments were carried out in selected sera. Ac sensitization was recorded in 96 (46.8%) patients on SPT. Strict relationship between Ac and D. pteronyssinus, B. germanica, P. monodon, or Apis mellifera reactivity on SPT was observed. Ac IgE recognition was seen in 60/131 (45.8%) patients, 49 (81.6%) of them SPT positive, and 5/14 IB reactors. Ac IgE sensitization was associated with Tabanus spp, A. mellifera, Vespula vulgaris, and Polistes dominula reactivity. A strict relationship between Ac IgE reactivity and Api m 1, Api m 2, Api m 3, Api m 5, and Api m 10 was recorded. IgE reactivity to AC was inhibited in 9/15 cases after serum absorption with the A. mellifera extract. Both SPT and IgE Ac reactivity is observed in about half of patients with a history of large local reactions to mosquito bites. The significant relationship between Ac sensitization and either extract or single bee venom components is suggestive of a "bee-mosquito syndrome" occurrence.