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Background: Anaphylaxis is increasing in incidence. This potentially fatal condition requires immediate intramuscular adrenaline as a vital part of early treatment. A 2002 survey of UK Senior House Officers showed a lack of knowledge regarding the recognition and management of anaphylaxis. Since then major changes in medical education and updated national guidelines have aimed to ensure that doctors can recognise and treat anaphylaxis appropriately., Objectives: To determine current knowledge concerning the recognition and management of anaphylaxis among junior doctors compared to their predecessors., Methods: Using the same methodology as in 2002, we asked 68 Foundation doctors to read five clinical scenarios potentially suggesting anaphylaxis and indicate how they would respond to each case. Their results were compared to those of Senior House Officers in 2002., Results: 68 of 107 (64%) junior doctors completed the questionnaire. All recognised the need for adrenaline in anaphylaxis, but only 74% selected the correct intramuscular route, and 34% the correct route and dose. 82% of junior doctors would inappropriately give adrenaline to the patient who had inhaled a foreign body (case 2). A higher percentage of the 2013 cohort indicated the correct route and dose of adrenaline in anaphylaxis than their 2002 colleagues. However, a greater percentage also selected adrenaline treatment inappropriately in non-anaphylactic case scenarios., Conclusions: Despite updated guidelines, junior doctors continue to have poor knowledge about the recognition and management of anaphylaxis, with some still considering inappropriate intravenous adrenaline. More effort should be given to the recognition of anaphylaxis in early medical training., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Background: Streptococcal throat infections and HLA Cw6 (Cw*06) have been implicated in the pathogenesis of psoriasis, particularly in the guttate form., Objectives: To study 105 Irish patients with psoriasis to investigate the relationship between streptococcal infections and Cw*06., Methods: The patients were divided into two groups: those with guttate psoriasis or guttate flare (guttate group, GG, n=64) and those with chronic plaque psoriasis (chronic plaque group, CPG, n=41)., Results: The incidence of Cw*06 was 86% in the GG and 73% in the CPG, which was not significantly different (P=0.1725) but the incidence in both groups was significantly higher than in an Irish control group (18%) (P<0.0001 vs. GG and P<0.0001 vs. CPG). Evidence for streptococcal infection was higher in the GG (56%) than in the CPG (32%) (P=0.0231). Of those patients with evidence of streptococcal infection, 30 of 36 GG (83%) and nine of 13 CPG (69%) patients possessed the Cw*06 genotype., Conclusions: Thus, not all patients with streptococcal-related psoriasis carry Cw*06. The role of Cw*06 in psoriasis, if any, has yet to be determined.

Objective: To document cardiac abnormalities secondary to pulmonary disease in primary antibody deficiency., Patients and Methods: A cross sectional audit study of patients from a regional immunology centre. Subjects undergoing two dimensional and Doppler transthoracic echocardiography were reviewed. Ventricular dimensions and function, valvular competence, and estimated pulmonary artery pressure were recorded. Data were compared with clinical variables, pulmonary function tests, and thoracic computed tomography data., Results: Nineteen patients with common variable immunodeficiency and one with IgG(2) subclass deficiency were included, mean age at diagnosis 37.5 years, mean estimated diagnostic delay 10.94 years. Left ventricular impairment was found in 15% and right heart dilatation in 20%. Pulmonary hypertension (mean pulmonary artery pressure >25 mm Hg) was found in 45% (9/20), graded as moderate (40-60 mm Hg) in 44% of cases. Pulmonary function was obstructive in 47% (9/19). Fifty five percent of the patients with computed tomography data within the last five years (10/18) had confirmed bronchiectasis. Patients with right heart dilatation and/or moderate pulmonary hypertension (n = 6) had a more prolonged diagnostic delay (p = 0.04) and more severe lung disease., Conclusion: Echocardiographic abnormalities are common in primary antibody deficiency, associated with diagnostic delay and pulmonary complications. Pulmonary hypertension should be considered in those with severe lung disease and can be confirmed by echocardiography.

Background: Hereditary angio-oedema is a rare, life-threatening, autosomal dominant condition caused by deficiency (type 1) or dysfunction (type 2) of complement C1 inhibitor. Serological assays to measure C1 inhibitor concentration and function are widely available. However, expert interpretation may not be., Objective: To review all cases within three NHS Trusts with a putative diagnosis of hereditary angio-oedema., Method: Review of laboratory results and clinical notes of 44 cases of presumed hereditary angio-oedema., Results: Audit revealed that 11 of 42 (26%) cases had been incorrectly considered to have a diagnosis of hereditary angio-oedema. Two of 44 had insufficient data to assess. All 11 had low functional C1 inhibitor recorded at presentation., Results: available in these 11 cases at the time of diagnosis showed a normal or borderline C4 level (>or= 50% of mean normal, in contrast to hereditary angio-oedema, where C4 was less than 40% of mean normal) indicating that the low C1 inhibitor levels were a result of sample decay. Cases incorrectly diagnosed were predominantly female and had a mean age at presentation of 40 years (compared with 22 years for type 1 hereditary angio-oedema). Six of the 11 cases were offered C1 inhibitor concentrate (pooled plasma product) as treatment., Conclusion: We recommend that all suspected cases of hereditary angio-oedema are reviewed, that specialist advice is sought before making the diagnosis and that the diagnosis is only made after initial abnormal serology is confirmed on a second sample.

Anti-tissue transglutaminase has been recently described as the predominant autoantigen in coeliac disease. We purified serum anti-tissue transglutaminase antibodies from three patients with coeliac disease by column chromatography and eluted tissue section-bound R1-anti-reticulin antibodies from sections of rat tissue for two of these. Lastly, we generated seven mouse MoAbs to guinea pig tissue transglutaminase. Each preparation was examined for anti-tissue transglutaminase, anti-endomysium, anti-R1 reticulin and anti-gliadin antibodies. Column-purified patient antibodies and 2/7 mouse MoAbs gave characteristic anti-endomysium/anti-R1 reticulin reactivity on rat, monkey and human tissue. All positive sera gave indistinguishable patterns of immunofluorescence on rat liver, kidney and stomach, monkey oesophagus, and human umbilical cord. Anti-R1-reticulin eluted from sections showed anti-tissue transglutaminase reactivity in 2/2 cases, but 0/2 showed anti-gliadin reactivity. In both, tissue section-eluted anti-R1 reticulin gave endomysial staining on monkey oesophagus. None of the mouse monoclonals, or any of the purified patient's anti-tissue transglutaminase or anti-R1-reticulin antibody showed any reactivity with gliadin. These data confirm tissue transglutaminase as the predominant autoantigen in coeliac disease and suggest that both anti-endomysium and anti-R1 reticulin reactivities seen in coeliac disease arise due to an immune response to tissue transglutaminase. Rigorous immunoabsorption was sufficient to abrogate reactivity in the tissue transglutaminase ELISA, but failed to completely absorb anti-endomysium and anti-reticulin activity. The possibility remains that some of the anti-endomysium and anti-reticulin activity was directed against antigens other than tissue transglutaminase.

Dermatitis herpetiformis (DH) is characterized by a rash and a gluten-sensitive enteropathy (GSE) indistinguishable from that of coeliac disease. T-cell-mediated mechanisms have been implicated in the pathogenesis of GSE. It seems feasible that intradermal injection of gluten, in patients known to have GSE, could lead to an influx of T cells sensitized to gluten, with subsequent development of a delayed hypersensitivity-type reaction. Six patients with DH and three normal subjects had intradermal injections of 'Frazer's fraction III' (FFIII; the partial peptic tryptic digest of gluten which is known to be antigenic) and phosphate-buffered saline (PBS) as a control. Skin biopsies were taken at PBS and FFIII injection sites at 48 h. In addition, two of the patients with DH had biopsies taken of FFIII injection sites at 6 h. Monoclonal antibodies and the avidin-biotin-peroxidase technique were used to stain for T cells in the skin biopsies. A monoclonal antibody to a neoepitope exposed in the terminal complement complex and an immunofluorescent method were used to detect the presence of terminal complement component in biopsies taken from two of the control subjects and two of the patients. Both patients and control subjects developed a weal and flare within a few minutes of injecting the FFIII, and this persisted for up to 6 h. No skin reaction was present in either the patients or the control subjects at 48 h. No skin reaction was visible at any time following injection of PBS.(ABSTRACT TRUNCATED AT 250 WORDS)

We studied the ability of wheat gluten and its subfractions to activate complement directly. A sensitive sandwich ELISA employing a monoclonal antibody (MoAb) to a C9 neoepitope exposed in the terminal complement complex (TCC), a functional haemolytic assay for C5b6 generation, and Laurell's electrophoretic method of estimating C3 conversion to C3bi were used. On a weight-for-weight basis, enzyme solubilized Frazer's fraction three of gluten (FIII) produced approximately 75% of the complement activation seen with the potent activator zymosan. By contrast, activation with whole insoluble undigested gluten was very weak and similar to that seen with ovalbumin or beta-lactoglobulin. The results were the same using normal human serum or sera from patients with coeliac disease, dermatitis herpetiformis, or hypogammaglobulinaemia as the complement source. Activation by both zymosan and FIII was blocked in 0.01 M EDTA, but not in 0.01 M EGTA with 0.0025 M magnesium chloride. Zymosan and FIII activated complement in a serum from a patient with an intact alternative pathway but classical pathway haemolytic activity (CH50) of zero. Preferential heat inactivation of the alternative pathway inhibited both zymosan- and FIII-induced activation. Our results confirm that FIII is a strong activator of the alternative pathway. We discuss how gluten enteropathy might be initiated by complement.

Sera from forty-six patients with dermatitis herpetiformis (DH) were examined for anti-gliadin antibodies (AGA) by the enzyme linked immunosorbent assay (ELISA) test and by a simple new immunofluorescent (IF) test. AGA were present in fifteen out of thirty-two patients taking a normal diet, but in none of the fourteen taking a gluten-free diet (GFD). The presence of circulating AGA was related to the severity of the enteropathy. AGA were present in all ten patients with a flat mucosa and in four of six with a convoluted mucosa, but in only one out of thirty patients with normal morphology of the small intestine. However, in those patients taking a normal diet and with a normal morphology of the intestine there was evidence of gluten sensitivity compared to those taking a GFD, as the intraepithelial lymphocyte count (IELC) was significantly raised in the peri-nuclear and supra-nuclear positions. The study shows that the presence of AGA in the serum is a good indication of the degree of gluten sensitivity as expressed by severe mucosal damage in patients with DH.

Sixty-two sera from children under investigation for gastrointestinal disease were tested for IgA, IgG and IgM antibodies to gliadin by two different methods: an immunofluorescent (IF) test, and a mixed reverse (solid-phase) passive antiglobulin haemadsorption (MRSPAH) test. There was good agreement between the tests. Both tests detected gliadin antibodies of IgG and IgA class in sera from children with active coeliac disease, which tended to disappear when a strict gluten-free diet was instituted. Serum antibodies to gliadin of IgA class were associated with severe small intestinal villous atrophy and were found almost exclusively in coeliac disease. Gliadin antibodies of IgG class were less disease-specific and were occasionally detected in sera from children with gastrointestinal disease other than coeliac disease--notably in sera from children with transient gluten intolerance.

A previous study using immunofluorescent techniques showed J-chain to be present in the uninvolved skin of patients with papillary IgA dermatitis herpetiformis (DH) in a distribution that was coextensive with the IgA. This implied that the IgA was dimeric and of mucosal origin. In this study, fifteen patients with papillary IgA deposits, fifteen with homogeneous-linear (HL) IgA deposits and four patients with granular-linear (GL) IgA deposits were tested for the presence of in vivo bound J-chain. All fifteen patients with papillary IgA deposits and all four with GL IgA deposits had J-chain staining coextensive with the IgA. However, only one of fifteen patients with HL IgA deposits demonstrated in vivo bound J-chain that could not be accounted for by coexisting IgM deposits. These findings indicate that the IgA in patients with HL deposits is qualitatively different from that in patients with papillary and GL IgA deposits and makes the distinction between the two types of linear fluorescence particularly important.

A multi-centre study is described in which thirty-five adult patients with papillary IgA dermatitis herpetiformis (DH) were compared with forty-two patients with linear IgA deposits, of whom thirty-four had homogeneous-linear (HL) and eight had granular-linear (GL) IgA deposits. The three groups were similar with regard to age of onset, presence of circulating immune complexes and auto-antibodies, incidence of spontaneous remission, histology of lesional skin and response to dapsone. There was a female predominance in the HL group in contrast to the male predominance in the other two. It was not possible to diagnose the HL group clinically. Some patients had a rash typical of DH whilst others resembled pemphigoid. In the majority, however, no specific diagnosis could be made with confidence. The GL group clinically resembled the DH group. The incidence of positive potassium iodide patch tests was greater in the DH group than in the other two. An associated enteropathy was found in 24% of patients in the HL group, 30% of patients in the GL group and 85% of patients in the DH group. Fifty-six percent of HL patients had HLA-B8 compared with 50% in the GL group and 88% in the DH group. Patients with linear IgA deposits may not be a uniform group, but until they can be divided into specific subgroups (e.g. by ultrastructural localization of the deposit or by response to a gluten-free diet) we propose that the term adult linear IgA diseases should be used to distinguish these patients from those with papillary IgA deposits.

The precise specificity of the R1 anti-reticulin antibody (ARA) associated with untreated gluten sensitive enteropathy (GSE) is unknown. Collagen type III, fibronectin and the non-collagenous reticulin component (NCRC) of Pras & Glynn (1973) co-distribute in tissues in a manner consistent with their being components of reticulin. We therefore used purified preparations of these connective tissue components in studies of the specificity of the ARA. Our results show that the ARA found in GSE does not react with collagen type III, fibronectin or NCRC.