Search

Immunoglobulin A vasculitis (IgAV) is a systemic vasculitis of the small vessels with formation of IgA immune complexes and a broad spectrum of clinical constellations. Typical manifestations include purpura, arthralgia or arthritis, enteritis and glomerulonephritis. The IgAV is the most common vasculitis in childhood with a mostly uncomplicated and self-limiting course. In adults IgAV is much less frequent but the course can be more complicated, especially with renal or gastrointestinal manifestations. Various triggers of IgAV including infections have been described, whereby impaired glycosylation of IgA1 with subsequent exposure of binding sites for autoantibodies is a pathophysiological precondition for the vasculitis. Therapeutic strategies with immunosuppressants are so far supported by low evidence, take the severity of the organ manifestations into account and are oriented towards the recommendations for the treatment of other vasculitides of small vessels. Benign courses are treated symptomatically. The long-term prognosis of IgAV is determined by the renal manifestation.Die Immunglobulin-A-Vaskulitis (IgAV) ist eine systemische Vaskulitis der kleinen Gefäße mit Ig(Immunglobulin)A-Immunkomplexbildung und einem breiten Spektrum klinischer Konstellationen. Typische Manifestationen sind Purpura, Arthralgien oder Arthritiden, Enteritis und Glomerulonephritis. Die IgAV ist die häufigste Vaskulitis im Kindesalter mit meist unkompliziertem und selbstlimitierendem Verlauf. Erwachsene erkranken deutlich seltener an einer IgAV, wobei die Verläufe insbesondere bei renaler oder gastrointestinaler Manifestation komplizierter sind. Verschiedene Trigger der IgAV, darunter Infektionen, wurden beschrieben, wobei eine gestörte Glykosylierung von IgA1 mit konsekutiver Freilegung von Bindungsstellen für Autoantikörper die pathophysiologische Voraussetzung für die Vaskulitis ist. Therapeutische Strategien mit Immunsuppressiva sind bisher mit geringer Evidenz unterlegt, berücksichtigen die Schwere der Organmanifestationen und orientieren sich an den Empfehlungen zur Behandlung anderer Vaskulitiden der kleinen Gefäße. Benigne Verläufe werden symptomatisch behandelt. Die langfristige Prognose der IgAV ist von der renalen Manifestation beeinflusst.

Patients with newly diagnosed COVID-19 (coronavirus disease 2019) develop antibodies against SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). To date, few data have been obtained of the prevalence of SARS-CoV-2-antibodies in general population and in asymptomatic outpatients in Germany.From March 26 to June 4 2020, 415 asymptomatic outpatients were tested prospectively in Northrhine-Westfalia (Germany), to detect SARS-CoV-2-IgG-antibodies. In case of a positive result, anti-SARS-CoV-2-IgA was determined additionally.5 of 415 asymptomatic outpatients had positive SARS-CoV-2-IgG-antibodies with a calculated prevalence of 1.2%. Reference range of anti-SARS-CoV-2-IgA and IgG was defined as ratio for negative0.8, borderline 0.8-1.1 and1.1 positive. The mean concentration of SARS-CoV-2-IgG-antibodies of the positive 5 outpatients was lower than in symptomatic patients with COVID-19 (n = 12) and positive PCR of SARS-CoV-2 (3.04 ± 2.58 versus 8.05 ± 6.70; p = 0.002). 4 of 5 patients had elevated SARS-CoV-2-IgA-antibodies (1.61 ± 0.82). In 408 screening-outpatients with negative anti-SARS-CoV-2-ELISA-IgG (0.8), the mean ratio was 0.25 ± 0.13. Two patients were in the borderline range (0.83 and 0.86).The prevalence of 1.2% of SARS-CoV-2-IgG-antibodies and consequently the rate of infection in asymptomatic outpatients in Northrhine-Westfalia (Germany) is low. The impact of virus neutralisation by antibodies and consequently immunization is the challenge of further investigations.

Coeliac disease and vitiligo are immune-mediated disorders that are often associated with other immune-mediated disorders. In a prospective study we included 174 patients with vitiligo between the ages of 3 and 79 years (mean 38.2 years) to investigate whether there is an increased risk for coeliac disease in patients with vitiligo. We determined immunoglobulin A and IgA- and IgG-antibodies against tissue transglutaminase, while also optionally measuring blood count, ferritin, and endomysial-IgA-antibodies. In 3 of 174 (1.7%) vitiligo patients, coeliac disease was diagnosed serologically and by duodenal biopsy. Assuming a coeliac disease prevalence of less than 0.0033%, the incidence is statistically significant. In two other patients with vitiligo, coeliac disease was already known and confirmed with biopsy. If these two patients are included in the calculation, 2.8% (5 von 176) of vitiligo patients have coeliac disease. This value is statistically significant even with a higher coeliac disease prevalence of 0.01. Thus, it is recommended that celiac-disease-specific antibodies also be determined during routine blood workup in vitiligo patients. In case of positive results, a gastroduodenoscopy with biopsy of the small intestine is recommended for diagnosis confirmation. If celiac disease is unlikely, a trial of gluten-free diet for a specific time should nevertheless be discussed with individuals affected by vitiligo because repigmentation appears possible.

Autoimmune blistering skin disorders represent a rare group of autoantibody-induced dermatoses against desmosomal and hemidesmosomal molecules. The common age of onset for pemphigus and pemphigoid, as well as dermatitis herpetiformis, encompasses the adult age, but all these disorders can be observed neonatally and/or during childhood. If the disease occurs postpartum or neonatally, physicians should consider transplacental transmission of pathogenic maternal immunoglobulin G (IgG)-autoantibodies, and both mother and child should be included in the diagnostic work up. If the disorder is suspected in childhood, early immunoserological testing and skin biopsies for direct immunofluorescence analyses are recommended for the correct diagnosis and subsequently for the right choice of treatment. First-line recommendations are nonhalogenated topical steroids, followed by oral dapsone. All therapies require preliminary examinations, e. g. enzyme-activity testing (as is glucose-6-phophate dehydrogenase in dapsone treatment). In refractory cases, further treatment choices like high-dose intravenous immunoglobins, plasmapheresis/immunoadsorption or targeted therapies like anti-CD20 autoantibody therapies are indicated. An intense dermatological support and good medical care are essential for an age-appropriate development of the child and to lower possible treatment-associated adverse events.

Linear IgA bullous dermatosis is a rare autoimmune blistering disease that occurs in both children and adults. Strings of pearls, crowns of jewels, rosettes and urticarial plaques can occur on the whole integument with emphasis on the face (particularly perioral area) and genitalia. Pruritus is common and may be severe. The presence of IgA deposits along the basement membrane can usually be identified using direct immunofluorescence (DIF) microscopy. The histological and clinical features of this disorder may mimic those of dermatitis herpetiformis.

The rare case of a 61-year-old patient suffering from linear IgA dermatosis is presented. The patient was previously hospitalized with chronic inflammatory bowel disease. The correct diagnosis of the disease was based on clinical and histological findings. Serological methods, such as indirect immunofluorescence, ELISA and immunoblotting are suitable for identification of the autoantibodies. In this case the detection of IgA antibodies along the basal membrane was achieved by direct immunofluorescence. Other bullous dermatoses with similar symptoms, such as an IgG-mediated bullous pemphigoid have to be excluded. The therapy of linear IgA dermatosis is ensured by steroid-containing topical agents, alongside antiseptic measures as well as systemic dapsone p.o.

The IgA nephropathy is the most frequent form of glomerulonephritis worldwide. In approximately 30% of patients a reduction in the glomerular filtration rate of approximately 50% is observed within 10 years. Patients with IgA nephropathy form IgG autoantibodies against galactose-deficient IgA1 antibodies. This results in deposition of these antibodies in the mesangium and activation of complement with mesangial hypercellularity, endocapillary hypercellularity, segmental glomerulosclerosis and atrophying interstitial fibrosis. The basic treatment for patients with IgA nephropathy consists of removing risk factors, in particular hypertension, with blockade of the renin-angiotensin-aldosterone system. Immunosuppressives were also investigated in various studies but a clear advantage was not observed.

Celiac disease is a relatively common immunological systemic disease triggered by the protein gluten in genetically predisposed individuals. Classical symptoms like chronic diarrhea, steatorrhea, weight loss and growth retardation are nowadays relatively uncommon. Diagnostic workup includes serological tests for IgA antibodies against tissue transglutaminase 2 (anti-TG2-IgA) and total IgA and histology of duodenal biopsies. Histomorphological classification should be done according to the modified Marsh-Oberhuber classification. Diagnosis of celiac disease should be based on serological, clinical, and histological findings. The only treatment is a life-long gluten-free diet. Unchanged or recurrent symptoms under gluten-free diet may indicate refractory celiac disease. Enteropathy-associated T-cell lymphoma and adenocarcinomas of the small intestine are known complications of celiac disease.

IgA nephropathy is the most common glomerulonephritis in Europe. The disease has been discovered in 1968 in Paris by Jean Berger at the Necker-Children's Hospital. Diagnosis is made by kidney biopsy and requires the presence of mesangial deposits of IgA. This form of glomerulonephritis can be seen in children and adults. In childhood, it most frequently presents within the context of Schoenlein-Henoch purpura. In adulthood, the most common form is limited to the kidney. Schoenlein-Henoch purpura can be seen in adults and manifests as a very aggressive vasculitis, usually in the context of a specific drug intake. The underlying pathophysiological concept today is an insufficient glycosylation of the IgA1 hinge region triggering the formation of autoantibodies against this site. Therapeutic options for the disease are limited. Important is optimal blood pressure control. Selected patients will profit from steroid therapy.Die IgA-Nephropathie ist mit Abstand die häufigste Glomerulonephritis in Europa. Sie wurde 1968 durch einen Zufall in Paris entdeckt. Um die Diagnose stellen zu können, wird eine Nierenbiopsie benötigt. Die Krankheit kann beim Kind und beim Erwachsenen auftreten. Beim Kind ist die häufigste Form die sogenannte rheumatoide Purpura Schönlein-Henoch, beim Erwachsenen die auf die Niere begrenzte IgA-Nephropathie, auch Bergersche Krankheit („maladie de Berger“) genannt. Selten kann es sich beim Erwachsenen um eine systemische Vaskulitis handeln. Eine rheumatoide Purpura Schönlein-Henoch beim Kind ist relativ häufig und hat einen gutartigen Verlauf, beim Erwachsenen tritt sie selten auf, ist meist durch Medikamente ausgelöst, und hat eine schlechte Prognose. Pathognomonisch sind bei allen Formen die mesangialen IgA-Ablagerungen in den Glomeruli. Die genaue Pathogenese ist nicht bekannt. Man geht davon aus, dass eine zu geringe Glykosylierung von IgA1-Proteinen mit Bildung von Autoantikörpern das grundlegende Problem ist. Therapeutisch ist vor allem eine gute Blutdruckeinstellung wichtig. Bestimmte Formen der IgA-Nephropathie profitieren von einer Steroidtherapie.

We report a case of a 63 year old woman with progressive small red spots that can not be diminished with pressure. They appeared on the feet first and spread out to the legs, trunk and arms. This was accompanied with non-bloody diarrhoea and the laboratory diagnostics showed minor impairment of the kidney. The biopsy of the skin showed deposits of immunoglobulin A and C3 complement in the stratum papillare of the small vessels and a necrosis of the wall, which made the diagnosis of the Schönlein-Henoch purpura clear. It was accompanied by a systemic participation of the gastrointestinal tract. The quick reversible renal insufficiency was rather interpreted as a prerenal cause, than as an origin of the Schönlein-Henoch purpura. We further discussed the diagnostic methods, the aetiology and the possible therapy options.Wir berichten über eine 63-jährige Patientin mit progredienten Petechien an den Füssen, die im Verlauf an beiden Beinen, am Stamm und später an den Armen auftraten. Begleitend bestanden nicht-blutige Durchfälle. Laborchemisch fiel eine Nierenbeeinträchtigung auf. Die Hautbiopsie zeigte in den Gefässen des Stratum papillare Immunglobulin-A- und Komplementfaktor-C3-Ablagerungen, sowie eine Wandnekrose, gut vereinbar mit einer Purpura Schönlein-Henoch. Systemisch mitbeteiligt war der Gastrointestinaltrakt. Wir diskutieren die diagnostischen Methoden, die Ätiologie und mögliche Therapieoptionen bei Purpura Schönlein-Henoch.

IgA pemphigus of the subcorneal pustular dermatosis type is a rare autoimmune blistering disease in the pemphigus spectrum. Patients are clinically characterized by extensive erythemas that primarily affect intertriginous areas. The erythematous macules are covered with numerous vesicles and pustules with occasional hypopyon formation. Histopathology shows subcorneal acantholysis with clefting and numerous neutrophils within the blister as well as in the edematous papillary dermis. IgA autoantibodies bind in vivo to keratinocytes within the upper half of the epidermis. Desmocollin 1, the autoantigen of this disease, is a member of desmosomal cadherins and is only expressed on more differentiated keratinocytes. The demonstration of circulating autoantibodies against desmocollin 1 in routine diagnosis is challenging and requires indirect immunofluorescence staining of desmocollin 1 transfected COS7 cells. We report a patient with a severe course of the disease who only responded to combined therapy with dapsone and acitretin.

Autoimmune bullous skin diseases represent a heterogenous group of disorders of skin and mucosa which are commonly associated with IgG or IgA autoantibodies against distinct adhesion molecules of the skin. The antibodyinduced loss of adhesion between epidermis and dermis results in blister formation and extensive erosions. There is a great need for rapidly establishing the diagnosis of these disorders since they may run a severe and potentially life-threatening course. In addition, because of their rarity and heterogeneous symptoms, autoimmune bullous skin diseases often pose a major diagnostic challenge. While histopathological examinations provide evidence for the level of blister formation, immunofluorescence microscopy has been established to identify tissue-bound and circulating autoantibodies. Direct immunofluorescence microscopy represents the gold standard for detecting tissue-bound autoantibodies. Indirect immunofluorescence microscopy with defined tissue substrates is considered the first step in detecting circulating autoantibodies. Confirmatory tests such as ELISA, immunoblot or immunoprecipitation analyses are performed utilizing recombinant proteins or keratinocyte extracts. The later assays can be used for primary diagnosis as well as for immunoserological follow-up. Systemic immunosuppressive drugs usually represent the main therapeutic regimen. Initially, systemic corticosteroids are commonly administered in combination with steroid-sparing, immunosuppressive agents. Novel targeted treatments such as immunoadsorption, rituximab or high-dose intravenous immunoglobulins have proven to be highly effective in severe and refractory pemphigus. This review presents a state-of-the-art algorithm for making the diagnosis of autoimmune bullous disorders and provides an overview on currently available therapeutic options.

Autoimmune bullous skin diseases are characterized by autoantibodies against adhesion molecules of the skin. Pemphigus is a disorder with an intraepidermal loss of adhesion and is characterized by fragile blisters and erosions. Pemphigus vulgaris often shows extensive lesions of the oral mucosa, while pemphigus foliaceus is commonly restricted to cutaneous involvement with puff pastry-like scale formation. Paraneoplastic pemphigus is obligatorily associated with malignancies and often presents as hemorrhagic stomatitis with multiforme-like exanthems. IgA pemphigus typically presents with pustules and annular plaques but not with mucosal involvement. The clinical spectrum of the pemphigoids includes tense blisters, urticarial plaques, and prurigo- like eczematous lesions. Pemphigoid gestationis mostly occurs during the last trimester of pregnancy and mucous membrane pemphigoid primarily involves the oral mucosa and conjunctivae and leads to scarring. Linear IgA bullous dermatosis manifests with tense blisters in a "cluster of jewels"-like pattern in childhood and is more heterogeneous in adulthood. Classical epidermolysis bullosa acquisita shows extensive skin fragility. Dermatitis herpetiformis is associated with gluten-sensitive enteropathy and manifests clinically with severe itching and papulovesicles on the extensor surfaces of the extremities and the lumbosacral area. The intention of the review is to demonstrate the heterogeneous clinical spectrum of autoimmune bullous disorders.

Linear IgA bullous dermatosis is an acquired autoimmune subepidermal blistering disease, characterized by linear IgA deposits at the basement membrane zone. Described in both children and adults, it occurs as tense pruritic vesicles and bullae in a "cluster of jewels" configuration with central crusting on an inflammatory elevated base. It is typically located on the face, anogenital region and trunk. Whilst the adult manifestations can be chronic, in children a spontaneous remission has often been reported. Our patient showed a spontaneous remission after 8 weeks of symptomatic topic treatment with methylprednisolone and oral cetirizine dihydrochloride.

It is generally recommended to vaccinate elderly people against tetanus. Is this really essential?The levels of antibodies to tetanus toxin in serum of 2936 individuals of various age groups were determined by means of an ELISA.Obviously, the antibody titers definitely diminish in the old individuals. About 50 % of people80 years possess antibody titers0.5 IU/ml and about 30 % antibody titers0.1 IU/ml, which means that they are not absolutely protected against tetanus.This, however is not due to a general decline of antibodies, since levels of immunoglobulins of the classes IgG, IgM and especially of IgA are higher with growing age.It can be assumed that the awareness for the necessity for vaccination is lacking.

A 69-year-old man presented with multiple recurrent oral ulcerations for about 20 years. After he began having difficulty in breathing and swallowing, esophagogastroscopy was performed and showed ulcerations, erosions and scars on the mucous membrane of the pharynx as well of the esophagus. Linear IgA disease (LAD) was diagnosed based on histopathological and immunofluorescence examinations. In this patient with LAD, the buccal, pharyngeal and esophageal mucosa was affected without involvement of the skin.

Antibody assays play an important role in the diagnosis of coeliac disease (coeliac sprue, gluten-sensitive enteropathy), a condition characterized by immunological intolerance to gluten from wheat and from proteins of related cereals in genetically predisposed persons. Enhanced concentrations of IgA-antibodies against tissue transglutaminase or endomysium under gluten-containing normal diet represent an important indication for a biopsy from the small intestine. Demonstration of typical changes in the mucose of the small intestine is still required for the definitive diagnosis of coeliac disease. Recently highly specific antibodies against deamidated gliadin peptides were detected in serum. These antibodies further improve the reliability of serologic diagnosis. The new assays for IgG-antibodies against deamidated gliadin peptides have a very high diagnostic accuracy and are comparable to IgA tissue transglutaminase antibodies. Further investigations have to show whether IgG-antibodies against deamidated gliadin peptides are a reliable disease marker also in case of IgA deficiency. Prospective studies are needed to show whether antibody assays could replace biopsy in the diagnosis of coeliac disease in a substantial number of patients.

The association of linear IgA disease (LAD), ulcerative colitis and scarring ocular involvement is very rare and represents a considerable therapeutic challenge. We report a 48-year-old male diagnosed with ulcerative colitis in 1995, who received long-term methylprednisolone therapy. Later, he developed ocular inflammation with conjunctival scarring and synechiae formation as well as episodes of vesicles. Although azathioprine was added to his regimen, the disease was not controlled. After the diagnosis of LAD was established, dapsone was added. With this therapy, the ocular inflammation decreased significantly and the methylprednisolone dose could be successfully tapered slowly without reappearance of vesicles.

With higher age, monoclonal gammopathies are more frequently diagnosed as the underlying cause of polyneuropathies. Whereas in approximately one-third of the patients, the gammopathy is related to multiple myeloma, lymphoma, other lymphoproliferative diseases, or amyloidosis, the remaining patients are diagnosed with monoclonal gammopathy of undetermined significance (MGUS). As underlined by the two reported cases, in IgG/IgA-type gammopathies electrophysiological findings of axonal lesions in mildly impaired patients are more likely to be found in patients with MGUS, while demyelinating polyneuropathies with more severe clinical impairment are more commonly seen in myeloma patients.

In Germany now, the recognition of Salmonella infections in pig herds is based on three different commercial tests detecting antibodies against Salmonella-derived lipopolysaccharide (LPS). However, a serious disadvantage of these tests, used so far, is the restricted detection of antibodies belonging predominantly to the immunoglobulin class g (IgG). Therefore, a new test was developed to detect three Ig classes (IgM, IgG and IgA). Different constellations between the three Ig classes allow the evaluation of the current infection status of each pig. Under field conditions, this was proved in three different vaccination trials using a commercial Salmonella Typhimurium live vaccine.

Membranous nephropathy (MN) is characterized by proteinuria and other symptoms of the nephrotic syndrome. In many cases, the etiology is unknown. Whether and how to treat MN is still a controversial question. Despite the use of corticosteroids and alkylating agents, up to 40% of patients still progress to end-stage renal failure.A 40-year-old male patient with biopsy-proven idiopathic MN was initially treated with prednisolone and chlorambucil because of a proteinuria of 22 g/d. Treatment with cyclosporine was started because the nephrotic syndrome failed to improve. Proteinuria was reduced to a minimum of 4 g/d. Cyclosporine was stopped after 17 months leading to a fast relapse. Therapy with an ACE inhibitor and AT(1) receptor antagonist and retreatment with cyclosporine improved proteinuria. Cyclosporine was terminated after a total of 24 months. 5 months later, relapse occurred with a high proteinuria of 34 g/d. The monoclonal anti-CD20 antibody rituximab (375 mg/m(2)) was given four times every 4 weeks. 4 weeks and 4 months after the end of treatment, proteinuria decreased to 780 mg/d and150 mg/d, but renal function remained impaired (creatinine clearance 65 ml/min, stage 2 according to K/DOQI). Now, remission of proteinuria (150 mg/d) has been stable for almost 2 years. However, renal insufficiency progressed further (creatinine clearance 45 ml/min, stage 3 according to K/DOQI).Rituximab offers the possibility for a targeted treatment of idiopathic MN. Based on the existing evidence and experience from this case, rituximab can be recommended as a new treatment option for MN, possibly before starting any treatment with cytotoxic agents and high-dose prednisolone carrying the risk of severe side effects. However, long-term results of this treatment are still lacking.

Mucous membrane pemphigoid is a subepidermal blistering autoimmune disorder characterized by predominant involvement of mucous membranes and the presence of autoantibodies against proteins of the dermal-epidermal junction. Lesions most frequently develop in the oral cavity followed, in descending order of frequency, by conjunctiva, nasopharynx, the anogenital region, skin, larynx, and oesophagus. When the lesions are restricted to the conjunctiva, the term ocular pemphigoid may be applied. Cicatrization of the plica is considered a pathognomonic sign in early disease. Recurrent conjunctival inflammation results in subepithelial fibrosis, which leads to fornix shortening, symblepharon formation and subsequent trichiasis and entropion. Even in the absence of conjunctival inflammation, ankyloblepharon may occur. In end stage disease, limbal stem cell deficiency, tear deficiency, and lid malpositions may occur and result in a total keratinization of the ocular surface. The diagnosis is based on clinical findings and the detection of linear deposits of IgG and/or IgA and/or C3 at the dermal-epidermal junction by direct immunofluorescence microscopy of a perilesional biopsy. Autoantibodies (against type XVII and VII collagen, laminin 5 and 6, alpha6beta4 integrin, BP230) have been detected in patient serum. In the case of ocular involvement, preferential reactivity against beta4 integrin has been described.

Summary Erythema elevatum diutinum is a rare chronic inflammatory skin disease of unknown etiology with a histopathology of a leukocytoclastic vasculitis. Clinical findings involve symmetrical livid-erythematous to red-brown papules and plaques or nodules which are initially soft but become firmer. The skin lesions are located over extensor surfaces and often over joints. Early treatment with dapsone, corticosteroids and antibiotics is sometimes effective. A patient with multiple myeloma displayed unusual lesions of erythema elevatum diutinum.

Summary To date, there is very little information regarding the pathomechanism of IgA anaphylactoid reactions and the management of affected patients. Five adult patients with common variable immunodeficiency (CVID) and a history of anaphylactic reactions due to the administration of immunoglobulin preparations were studied. The activity of anti-IgA was determined by the gel agglutination technique using IgA-coated beads. Antibodies to IgA were detected in the serum of all five patients. Initially, IgA ‘depleted’ intravenous (i.v.) IgG preparations were infused carefully into the patients until the activity of anti-IgA was decreased significantly or became undetectable. Subsequently, unselected i.v. IgG preparations were infused, and the activity of anti-IgA was abolished in all cases. Intravenous IgG long-term administration results in tolerance induction in patients with IgA anaphylactoid reactions. This tolerance appears to be related to antibody blockage in the circulation and an inhibition of antibody production. Most importantly, IgA appears to play an important role in the treatment of CVID. Patients with IgA anaphylactoid reactions can be treated safely with IgA containing i.v. IgG preparations following tolerance induction.

Antigenic targets of monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM) paraproteins have been suggested to play an important role as growth stimulators in the pathogenesis of these neoplasms. To identify such targets, we screened cDNA libraries from human testis, lung and breast cancer, bovine and porcine muscle and wheat germ for reactivity with paraproteins in the sera from 115 patients with MGUS and MM. Of >6 x 10(8) paraprotein-antigen interactions screened, an IgA paraprotein from a female patient bound to sperm-specific cylicin-2, and 3 IgG paraproteins bound to tripeptidyl-peptidase-II (TPP-2), insulin-like growth-factor binding-protein-2 (IGFBP-2) and porcine kinesin. Specificity was confirmed by reverse Western blots using recombinant antigens. The broad spectrum of auto-, allo- and heteroantigens as targets of human paraproteins in patients without signs of chronic antigenic stimulation renders a causal role of the antigenic stimulus in the pathogenesis of MGUS and MM unlikely.

In Germany, the program for controlling salmonella infections in pigs is based on tests detecting salmonella-lipopolysaccharide (LPS) induced antibodies in meat-juice or blood. These conventional tests which are based on the technology of enzyme-linked immunosorbent assay (ELISA) detect exclusively or mainly immunoglobulin(lg)G antibodies. Meanwhile, novel ELISA systems (WCE-ELISA, 3-Isotype-Screening-ELISA) have been developed, which additionally detect the antibody classes IgM and IgA.This fact enables the registration of fresh salmonella infections (starting with day 5 p.i.) and thus, the distinction between early and older infections. The results show that animals with early salmonella infections appear significantly more often in herds with a high than with a low prevalence. With the newly developed tests this group of animals can be detected much more efficiently and precisely than with the tests used so far. Due to their clearly improved sensitivity the application of the WCE-ELISA and the 3-Isotype-Screening-ELISA in terms of the QS-Salmonella-Monitoring program can therefore significantly improve the selection of farms with potential salmonella excretors. Additionally, the WCE-ELISA can be applied very suitable for the examination of individual animals.

We report on a 52-year-old female patient with recurrent neurosarcoidosis and an "atypical" course of celiac disease, with mild clinic features, positive IgA-antibodies and histology. In our patient, the IgA-antibodies led to a false positive troponin I test, and we initially suspected an acute coronary syndrome. With dietary treatment of the celiac disease, the antibodies decreased and the troponin I test became negative. The coincidental occurrence of sarcoidosis and "potential" celiac disease (positive antibodies only) has been reported. The coincidence of an "atypical" celiac disease and sarcoidosis is rare.

Celiac disease is a genetically determined bowel disease also influenced by exogenous factors in which exposure to grain components triggers a chronic immune response with intestinal symptoms. Dermatitis herpetiformis represents the cutaneous manifestation of celiac disease. While intense pruritus is the characteristic symptom, clinical signs can be highly variable, ranging from grouped papulovesicles with excoriations or eczema-like lesions to minimal variants of discrete erythema and digital purpura. Diagnosis depends on direct fluorescence studies of perilesional skin displaying granular IgA deposits in dermal papillae. Suspecting and then searching for dermatitis herpetiformis is often clinically challenging, as the disease is a true chameleon with many clinical faces. Dapsone therapy alleviates the cutaneous symptoms and signs, but does not prevent the systemic complications of celiac disease; thus, strict adherence to a gluten-free diet is strongly advisable.