Prophylactic anticoagulation with enoxaparin: Is the subcutaneous route appropriate in the critically ill?

BACKGROUND

Subcutaneously administered low-molecular-weight heparins are widely used for prevention of venous thromboembolism. The appropriateness of the subcutaneous route in critically ill patients has never been established.

OBJECTIVE

To determine anti-Xa activities in critically ill patients and in noncritically ill patients receiving prophylactic doses of subcutaneous enoxaparin.

DESIGN

Prospective, controlled, open-labeled study.

SETTING

Tertiary medical-cardiologic-postoperative intensive care unit and a general medical ward at a university hospital.

PATIENTS

A total of 16 intensive care unit patients (group 1; age, 61.1 +/- 16 yrs; male/female ratio, 7/9; Acute Physiology and Chronic Health Evaluation II score, 20.9 +/- 7; mechanical ventilation, n = 15; vasopressors, n = 13) and 13 noncritically ill medical patients (group 2; age, 61.7 +/- 9 yrs; male/female ratio, 7/6) were studied. Body mass index (25.7 +/- 5 vs. 24 +/- 6 kg/m2, p = not significant) was comparable and serum creatinine levels (0.83 +/- 0.25 vs. 1.07 +/- 0.3 mg/dL, group 1 vs. 2) were within the normal range in both groups. Patients with impaired renal function, receiving hemofiltration, or requiring therapeutic anticoagulation were not eligible.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Anti-Xa activities were determined at 0, 1, 3, 6, and 12 hrs after a single daily subcutaneous dose of 40 mg enoxaparin on day 1 and at 3 hrs after 40 mg of enoxaparin on days 2-5. Mean anti-Xa levels at 0 to 12 hrs were consistently lower in group 1 compared with group 2 by analysis of variance (p =.001 between groups and over time), as was the area under the curve at 0 to 12 hrs (2.6 +/- 1 vs. 4.2 +/- 1.7 units x mL(-1) x hr(-1), group 1 vs. 2, p =.008). Significant differences in anti-Xa activity were also found on days 2-5 (p =.001). Peak anti-Xa activities at 3 hrs after administration were negatively correlated with the body mass index (r = -.41, p <.03). No correlation was found between the anti-Xa activity at 3 hrs and the dose of norepinephrine (r =.12, p =.7).

CONCLUSION

Critically ill patients with normal renal function demonstrated significantly lower anti-Xa levels in response to a single daily dose of subcutaneous enoxaparin when compared with medical patients in the normal ward.

Possible modes of allergen-specific sensitization and boosting in an atopic child

Several studies document that allergen-specific IgE levels are boosted by allergen contact via the respiratory tract in allergic patients. Only few data are available on whether other routes of allergen contact have an influence on systemic IgE responses. We report the case of a boy who developed egg allergy after heavy consumption of eggs by the mother during pregnancy and breast feeding. In contrast to other children who outgrow egg allergy during the first years of life, the boy experienced further dramatic increases in hen egg-specific IgE antibodies after prolonged consumption of ostrich eggs containing cross-reactive allergens. IgE antibodies to most of the important respiratory allergens remained either low or not detectable. The dramatic increases in hen egg-specific IgE antibody levels after oral intake of allergens demonstrate that systemic IgE responses in allergic patients can be strongly boosted by allergen contact via routes other than the respiratory tract.

Exocrine pancreatic dysfunction in sepsis

BACKGROUND

Sepsis in critical illness is associated with the progressive failure of multiple organs. This study aims to establish a correlation between the severity of sepsis and exocrine pancreatic dysfunction.

MATERIALS AND METHODS

In a prospective cohort study pancreatic exocrine function was tested by means of a secretin-cholecystokinin test in 21 critically ill, mechanically ventilated patients with sepsis according to criteria of the American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference Committee (ACCP/SCCM): 11 patients with shock and 10 patients without shock. Data were compared with seven healthy controls.

RESULTS

The volume of duodenal fluid was not statistically different in the three groups. Sepsis patients without shock had significantly reduced content of amylase and chymotrypsin in duodenal juice compared with healthy controls (P < 0.01). Secretion of amylase, chymotrypsin, trypsin (P < 0.01 each) and bicarbonate in duodenal fluid (P < 0.05) was impaired in the septic shock patients when compared with the healthy controls. The content of trypsin was different between sepsis patients and septic shock patients (P < 0.05). Spearman correlation analysis was significant between the amylase secretion and the APACHE III and SOFA scores (P < 0.01). The SOFA score was also related to secretion of trypsin (P < 0.05). In patients on pressor therapy, use of norepinephrine was associated with a significant decrease in bicarbonate secretion (P < 0.05).

CONCLUSIONS

Sepsis is associated with secretory pancreatic dysfunction that is worse in septic shock than in sepsis without shock. Impaired exocrine function was significantly correlated to the APACHE III and SOFA scores.

Microarrayed recombinant allergens for diagnosis of allergy

We suggest that the coapplication of recombinant allergens and microarray technology can lead to the development of new forms of multi-allergen tests which allow the determining and monitoring of complex sensitization profiles of allergic patients in single assays. The allergen extracts which have so far been used for diagnosis only allowed the determining of whether an allergic patient is sensitized against a particular allergen source, but the disease-eliciting allergens could not be identified. Through the application of recombinant DNA technology a rapidly growing panel of recombinant allergen molecules has become available which meanwhile comprises the epitope spectrum of most of the important allergen sources. We demonstrate that microarray technology can be used to establish multi-allergen tests consisting of microarrayed recombinant allergen molecules. Microarrayed recombinant allergens can be used to determine and monitor the profile of disease-eliciting allergens using single tests that require minute amounts of serum from allergic patients. The wealth of diagnostic information gained through microarray-based allergy testing will likely improve diagnosis, prevention and treatment of allergy.

Analysis of the sensitization profile towards allergens in central Africa

BACKGROUND

Almost no information is available regarding the prevalence of IgE-mediated allergies and the disease-eliciting allergens in tropical Africa.

OBJECTIVE

To study IgE-mediated allergies and the allergen profile in allergic patients from Zimbabwe.

METHODS

The frequency of sensitization to common environmental allergen sources was determined by skin prick testing in 650 allergic patients from Zimbabwe. Fifty representative sera were analysed for IgE reactivity to 20 respiratory and 20 food allergen extracts by multiallergen extract testing. The IgE reactivity profiles to recombinant pollen and mite allergens were compared between grass pollen- and mite-sensitized patients from Zimbabwe and central Europe. Sera from grass pollen-allergic patients were also analysed for IgE reactivity to nitrocellulose-blotted natural timothy grass and Bermuda grass pollen allergens.

RESULTS

IgE-mediated allergies were found to be common in Zimbabwe. Similar to the situation in central Europe, mites and grass pollens represented the most prevalent allergen sources. However, the IgE reactivity profiles determined with single recombinant pollen and mite allergens revealed interesting differences between the European and African patients, which most likely reflect the local allergen exposure.

CONCLUSIONS

The striking differences regarding sensitization to grass pollen and mite allergens between African and European patients revealed by recombinant allergen-based testing emphasize the need for component-resolved allergy testing to optimize allergy prevention and therapy in different populations.

Recombinant fish parvalbumins: Candidates for diagnosis and treatment of fish allergy

Fish and fish products represent one of the most important causes of IgE-mediated food hypersensitivity. In sensitized individuals contact with and consumption of fish can lead to severe health problems, ranging from urticaria and dermatitis to angiedema, diarrhoea, asthma and, at worst, systemic anaphylactic reactions and death. Parvalbumin, a small calcium-binding protein present in the muscles of vertebrates, was identified as the major fish allergen. We describe the isolation and characterization of cDNA clones coding for carp parvalbumin by IgE immunoscreening of a carp muscle expression library. These clones will be the basis for the production of recombinant carp parvalbumin, a useful tool for in vitro and in vivo diagnosis of fish allergy.

Characterization of a novel isoform of alpha-nascent polypeptide-associated complex as IgE-defined autoantigen

The nascent polypeptide-associated complex is required for intracellular translocation of newly synthesized polypeptides in eukaryotic cells. It may also act as a transcriptional coactivator in humans and various eukaryotic organisms and binds to nucleic acids. Recently, we provided evidence that a component of nascent polypeptide-associated complex, alpha-nascent polypeptide-associated complex, represents an IgE-reactive autoantigen for atopic dermatitis patients. By oligonucleotide screening we isolated a complete cDNA coding for a so far unknown alpha-nascent polypeptide-associated complex isoform from a human epithelial cDNA library. Southern blot hybridization experiments provided further evidence that alpha-nascent polypeptide-associated complex is encoded by a gene family. Recombinant alpha-nascent polypeptide-associated complex was expressed in Escherichia coli as a soluble, His-tagged protein, and purified via nickel affinity chromatography. By circular dichroism analysis it is demonstrated that purified recombinant alpha-nascent polypeptide-associated complex represents a folded protein of mixed alpha-helical and beta-sheet conformation with unusual high thermal stability and remarkable refolding capacity. Complete recombinant alpha-nascent polypeptide-associated complex (215 amino acids) and its 86 amino acid C-terminal fragment specifically bound IgE autoantibodies. Recombinant alpha-nascent polypeptide-associated complex also inhibited IgE binding to natural alpha-nascent polypeptide-associated complex, demonstrating the presence of common IgE epitopes between the recombinant and natural protein. Furthermore, recombinant alpha-nascent polypeptide-associated complex induced specific lymphoproliferative responses in peripheral blood mononuclear cells of a sensitized atopic dermatitis patient. As has been proposed for environmental allergens it is possible that T cell responses to IgE-defined autoantigens may contribute to the chronic skin manifestations in atopic dermatitis.

Purification, structural and immunological characterization of a timothy grass (Phleum pratense) pollen allergen, Phl p 4, with cross-reactive potential

Almost 500 million people worldwide suffer from Type I allergy, a genetically determined immunodisorder which is based on the production of IgE antibodies against per se harmless antigens (allergens). Due to their worldwide distribution and heavy pollen production, grasses represent a major allergen source for approximately 40% of allergic patients. We purified Phl p 4, a major timothy grass (Phleum pratense) pollen allergen with a molecular mass of 61.3 kDa and a pl of 9.6 to homogeneity. Circular dichroism spectroscopical analysis indicates that Phl p 4 contains a mixed alpha-helical/beta-pleated secondary structure and, unlike many other allergens, showed no reversible unfolding after thermal denaturation. We show that Phl p 4 is a major allergen which reacts with IgE antibodies of 75% of grass pollen allergic patients (n=150) and induces basophil histamine release as well as immediate type skin reactions in sensitized individuals. Phl p 4-specific IgE from three patients as well as two rabbit-anti Phl p 4 antisera cross-reacted with allergens present in pollen of trees, grasses, weeds as well as plant-derived food. Rabbit antibodies raised against Phl p 4 also inhibited the binding of allergic patients IgE to Phl p 4. Phl p 4 may thus be used for diagnosis and treatment of sensitized allergic patients.

Molecular and immunological characterization of a novel timothy grass (Phleum pratense) pollen allergen, Phl p 11

BACKGROUND

Allergy to grass pollen is typically associated with serum IgE antibodies to group 1 and/or group 5 allergens, and additionally often to one or several less prominent allergens. Most of the grass pollen allergens identified to date have been characterized in detail by molecular, biochemical and immunological methods, timothy grass being one of the most thoroughly studied species. However, a 20-kDa allergen frequently recognized by IgE antibodies from grass pollen allergics has so far escaped cloning and molecular characterization.

OBJECTIVE

To clone and characterize the 20 kDa timothy grass pollen allergen Phl p 11.

METHODS

Phl p 11 cDNA was cloned by PCR techniques, utilizing N-terminal amino acid sequence obtained from the natural allergen. Phl p 11 was expressed as a soluble fusion protein in Escherichia coli, purified to homogeneity and used for serological analysis and to study Phl p 11 specific induction of histamine release from basophils and skin reactivity in sensitized and control subjects.

RESULTS

Phl p 11 cDNA defined an acidic polypeptide of 15.8 kDa with homology to pollen proteins from a variety of plant species and to soybean trypsin inhibitor. The sequence contained one potential site for N-linked glycosylation. Serological analysis revealed that recombinant Phl p 11 shared epitopes for human IgE antibodies with the natural protein and bound serum IgE from 32% of grass pollen-sensitized subjects (n = 184). Purified recombinant Phl p 11 elicited skin reactions and dose-dependent histamine release from basophils of sensitized subjects, but not in non-allergic controls.

CONCLUSION

As the first representative of group 11 grass pollen allergens, Phl p 11 has been cloned and produced as a recombinant protein showing allergenic activity. One-third of grass pollen-sensitized subjects showed specific IgE reactivity to recombinant Phl p 11, corresponding in magnitude to a significant proportion of specific IgE to grass pollen extract.

A major IgE epitope-containing grass pollen allergen domain from Phl p 5 folds as a four-helix bundle

Phl p 5, a 29 kDa major allergen from timothy grass pollen, is one of the most reactive members of group 5 allergens. Its sequence comprises two repeats of a novel alanine-rich motif (AR) whose structure and allergenic response are still mostly unknown. We report here a structural characterization of an immunodominant fragment of Phl p 5, Phl p 5(56-165) which comprises the first AR repeat. Recombinant (r)Phl p 5(56-165) was expressed in Escherichia coli, purified to homogeneity and shown to be sufficient to react with serum IgE from 90% of grass pollen allergic patients. Using NMR spectroscopy, we show conclusively that the fragment forms a compact globular domain which is, however, prone to degradation with time. The rPhl p 5(56-165) fold consists of a four-helix bundle held together by hydrophobic interactions between the aromatic rings and aliphatic side chains. This evidence gives clear indications about the structure of the full-length Phl p 5 and provides a rational basis for finding ways to stabilize the fold and designing therapeutic vaccines against grass pollen allergy.

Ankylosing spondylitis, psoriatic arthritis, and reactive arthritis show increased bone resorption, but differ with regard to bone formation

OBJECTIVE

To test if markers of bone metabolism are altered in patients with seronegative spondyloarthropathies (SSpA).

METHODS

We studied biochemical markers of bone resorption and bone formation, osteoprotegerin (OPG), and bone mineral density (BMD) in patients with psoriatic arthritis (PsA), ankylosing spondylitis (AS), and reactive arthritis (ReA) and healthy volunteers.

RESULTS

The bone resorption markers urinary deoxypyridinoline and crosslinked telopeptide of collagen-I were significantly increased in patients with AS, PsA, and ReA; in PsA they correlated with the acute phase response (C-reactive protein and erythrocyte sedimentation rate). The bone formation markers were divergent: bone-specific alkaline phosphatase was increased in PsA, but not in AS or ReA. Osteocalcin levels were only elevated in AS. Serum levels of OPG were significantly increased in both AS and PsA. Dual energy x-ray absorptiometry (DEXA) measurements of lumbar spine and femoral neck revealed osteopenia in patients with AS, whereas the DEXA distribution was within normal range in PsA.

CONCLUSION

Our data indicate high and, particularly in AS, unbalanced bone turnover in SSpA, consistent with the decrease in BMD found in patients with AS.

The allergen profile of ash (Fraxinus excelsior) pollen: cross-reactivity with allergens from various plant species

BACKGROUND

Ash, a wind-pollinated tree belonging to the family Oleaceae, is distributed world-wide and has been suggested as a potent allergen source in spring time.

OBJECTIVE

The aim of this study was to determine the profile of allergen components in ash pollen in order to refine diagnosis and therapy for patients with sensitivity to ash pollen

METHODS

The IgE reactivity profile of 40 ash pollen-allergic patients was determined by immunoblotting. Antibodies raised to purified pollen allergens from tree and grass pollens were used to identify cross-reactive structures in ash pollen extract. IgE immunoblot inhibition studies were performed with recombinant and natural pollen allergens to characterize ash pollen allergens and to determine the degree of cross-reactivity between pollen allergens from ash, olive, birch, grasses and weeds.

RESULTS

The allergen profile of ash pollen comprises Fra e 1, a major allergen related to the major olive allergen, Ole e 1, and to group 11 grass pollen allergens, the panallergen profilin, a two EF-hand calcium-binding protein, a pectinesterase-like molecule and an allergen sharing epitopes with group 4 grass pollen allergens. Thus, the relevant allergens of ash are primarily allergens that share epitopes with pollen allergens from other tree, grass and weed species.

CONCLUSIONS

Allergic symptoms to ash pollen can be the consequence of sensitization to cross-reactive allergens from other sources. The fact that ash pollen-allergic patients can be discriminated on the basis of their specific IgE reactivity profile to highly or moderately cross-reactive allergens has implications for the selection of appropriate forms of treatment.

Quantitative ultrasound in the assessment of bone status of patients suffering from rheumatic diseases

OBJECTIVE

To explore the effects of rheumatic diseases and glucocorticoids on bone mass a group of patients suffering from systemic lupus erythematosus (SLE, n=18) and rheumatoid arthritis (RA, n=22) were examined.

DESIGN

We examined 40 patients and 48 controls with quantitative ultrasound (QUS) and dual-energy X-ray absorptiometry (DXA).

RESULTS

QUS (broadband ultrasound attenuation, BUA; speed of sound, SOS) values were found to be significantly lower in patients than in controls ( P<0.001). QUS measurements were moderately correlated with DXA measurements (kappa score ( kappa) 0.28 at the lumbar spine, and 0.46 at the femoral neck). There were no significant relations between the dosage of glucocorticoids and QUS parameters.

CONCLUSION

In patients suffering from inflammatory rheumatic diseases QUS values were significantly decreased. SOS but not BUA and DXA measurements reflected disease activity assessed by erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). QUS reflects different aspects of bone status compared with DXA.

Recombinant carp parvalbumin, the major cross-reactive fish allergen: a tool for diagnosis and therapy of fish allergy

IgE-mediated reactions to fish allergens represent one of the most frequent causes of food allergy. We have constructed an expression cDNA library from carp (Cyprinus carpio) muscle in phage lambda gt11 and used serum IgE from a fish allergic patient to isolate 33 cDNA clones that coded for two parvalbumin isoforms (Cyp c 1.01 and Cyp c 1.02) with comparable IgE binding capacities. Both isoforms represented calcium-binding proteins that belonged to the beta-lineage of parvalbumins. The Cyp c 1.01 cDNA was overexpressed in Escherichia coli, and rCyp c 1.01 was purified to homogeneity. Circular dichroism analysis and mass spectroscopy showed that rCyp c 1.01 represented a folded protein with mainly alpha-helical secondary structure and a molecular mass of 11,416 Da, respectively. rCyp c 1.01 reacted with IgE from all fish-allergic patients tested (n = 60), induced specific and dose-dependent basophil histamine release, and contained most of the IgE epitopes (70%) present in natural allergen extracts from cod, tuna, and salmon. Therefore, it may be used to identify patients suffering from IgE-mediated fish allergy. The therapeutic potential of rCyp c 1.01 is indicated by our findings that rabbit Abs raised against rCyp c 1.01 inhibited the binding of IgE (n = 25) in fish-allergic patients to rCyp c 1.01 between 35 and 97% (84% mean inhibition) and that depletion of calcium strongly reduced IgE recognition of rCyp c 1.01. The latter results suggest that it will be possible to develop strategies for immunotherapy for fish allergy that are based on calcium-free hypoallergenic rCyp c 1.01 derivatives.

IgA autoreactivity: a feature common to inflammatory bowel and connective tissue diseases

The immunopathogenic mechanisms in inflammatory bowel disease (IBD) are not yet fully established. The aim of this study was to determine the profile and magnitude of IgA and IgG autoantibodies in IBD patients. The autoantigen profile defined by IgA and IgG antibodies from 24 IBD (14 Crohn's disease CD], 10 ulcerative colitis UC]), three coeliac, 12 connective tissue disease (CTD) patients and 10 healthy individuals was studied in human cellular extracts by Western blotting. The magnitude of the IgA and IgG1-4 subclass responses was measured by ELISA. IBD patients could not be distinguished from healthy individuals on the basis of IgG autoantibodies to Western blotted proteins. IgG subclass analysis indicated no clear bias towards Th1 or Th2 immune responses in IBD or CTD. In accordance with previous work, we found that IgA autoreactivity was strongest in coeliac disease patients. Unexpectedly, IBD as well as CTD patients exhibited strong IgA autoantibody reactivities to components of similar molecular weights (16-80 kD) in intestinal and non-intestinal epithelial cell lines. Our data indicate immunopathogenic similarities between IBD and CTD.

Microarrayed allergen molecules: diagnostic gatekeepers for allergy treatment

Type I allergy is an immunoglobulin E (IgE)-mediated hypersensitivity disease affecting more than 25% of the population. Currently, diagnosis of allergy is performed by provocation testing and IgE serology using allergen extracts. This process defines allergen-containing sources but cannot identify the disease-eliciting allergenic molecules. We have applied microarray technology to develop a miniaturized allergy test containing 94 purified allergen molecules that represent the most common allergen sources. The allergen microarray allows the determination and monitoring of allergic patients' IgE reactivity profiles to large numbers of disease-causing allergens by using single measurements and minute amounts of serum. This method may change established practice in allergy diagnosis, prevention, and therapy. In addition, microarrayed antigens may be applied to the diagnosis of autoimmune and infectious diseases.

Evolution of IgM, IgE and IgG(1-4 )antibody responses in early childhood monitored with recombinant allergen components: implications for class switch mechanisms

The formation of IgE antibodies against environmental allergens represents the hallmark of type I allergy. Data from in vitro cultured cells and experimental animal models provide controversial evidence for isotype switching from IgM to IgE production via sequential as well as non-sequential (i.e. direct) class switch. We analyzed the evolution of IgE responses in 11 children developing birch pollen and/or grass pollen allergy during the first 7 years of life using purified recombinant allergen molecules (major birch pollen allergen, Bet v 1; major timothy grass pollen allergens, Phl p 1, Phl p 2, Phl p 5). Demographic, clinical and serological data indicated a postnatal sensitization to pollen allergens. A parallel development of IgG(1-4) and IgE responses to recombinant allergen molecules compatible with a strictly sequential class switch to IgE was observed only in one child. The only partly synchronized and dissociated development of allergen-specific antibody responses found in all other cases can be best explained by a partly sequential class switch involving few switch stations or, more likely, by direct class switching. Kinetics and courses of allergen-specific antibody responses (IgM, IgG(1-4), IgE) during the first years of life suggest that, once established, allergen-specific IgE responses are driven by antigen contact rather than by cytokines controlling class switch to IgE.

Mutants of the major ryegrass pollen allergen, Lol p 5, with reduced IgE-binding capacity: candidates for grass pollen-specific immunotherapy

More than 400 million individuals are sensitized to grass pollen allergens. Group 5 allergens represent the most potent grass pollen allergens recognized by more than 80 % of grass pollen allergic patients. The aim of our study was to reduce the allergenic activity of group 5 allergens for specific immunotherapy of grass pollen allergy. Based on B- and T-cell epitope mapping studies and on sequence comparison of group 5 allergens from different grasses, point mutations were introduced by site-directed mutagenesis in highly conserved sequence domains of Lol p 5, the group 5 allergen from ryegrass. We obtained Lol p 5 mutants with low IgE-binding capacity and reduced allergenic activity as determined by basophil histamine release and by skin prick testing in allergic patients. Circular dichroism analysis showed that these mutants exhibited an overall structural fold similar to the recombinant Lol p 5 wild-type allergen. In addition, Lol p 5 mutants retained the ability to induce proliferation of group 5 allergen-specific T cell lines and clones. Our results demonstrate that a few point mutations in the Lol p 5 sequence yield mutants with reduced allergenic activity that represent potential vaccine candidates for immunotherapy of grass pollen allergy.

Skin test results but not serology reflect immediate type respiratory sensitivity: a study performed with recombinant allergen molecules

The diagnosis of type I allergy, an IgE-antibody-mediated hypersensitivity disease affecting more than 25% of the population, is based on the measurement of allergen-specific serum IgE levels and provocation testing. Whether the determination of allergen- specific serum IgE levels can replace in vivo provocation testing for allergy diagnosis is a controversial issue. We used purified recombinant timothy grass and birch pollen allergens to compare by skin prick and nasal provocation testing as well as by serology in vivo sensitivity with antibody-binding capacity in 24 pollen allergic patients and eight control individuals. Results from biologic tests were correlated with each other and with allergen-specific IgE and IgG1-4 levels. IgE-reactive allergens induced immediate skin and nasal reactions, but the intensity of the allergic tissue reactions was not correlated with either the levels of allergen-specific IgE or the levels of allergen-specific IgG antibodies. Less frequently detected allergens with low IgE-binding capacity were able to induce strong allergic reactions comparable to those caused by major allergens with high IgE-binding capacity. In contrast, skin test and nasal provocation results were significantly correlated (r = 0.63, p < 0.01). Our study thus demonstrates on a molecular level that skin testing provides a better reflection of immediate type respiratory sensitivity than serologic measurements. These results have implications for allergy diagnosis and, in particular, for the selection of relevant allergen components for specific immunotherapy.

Clinical application of rapid quantitative determination of cardiac troponin-T in an emergency department setting

OBJECTIVES

We analysed the clinical use of Troponin-T compared to creatine kinase MB in a non-trauma emergency department setting.

BACKGROUND

A newly established single specimen quantitative Troponin T assay allows the clinical application of this parameter. METHODS. Five-hundred Troponin T tests were provided for use by emergency physicians who could combine them with the routine laboratory tests without restriction as to the indication or number of tests per patient. The number of tests per patient, time frame, final diagnosis and additional clinical information gained were recorded. All patients were followed for at least 6 months to verify the diagnosis and to assess the occurrence of cardiac events (nonfatal AMI or cardiac death). The ability of Troponin T and creatine kinase MB tests to predict cardiac events within 6 months were compared.

RESULTS

The 500 Troponin T tests were used in 249 patients (median two tests per patient (range 1-5)) within 41 days. The final diagnosis revealed coronary heart disease in 85, non-coronary heart disease in 39, non-cardiac chest pain in 86 and other diagnoses in 39 of the patients. In 14 patients with an elevated creatine kinase MB, myocardial damage could safely be ruled out by a negative Troponin T, in six patients with a normal creatine kinase MB minor myocardial damage could be detected by a positive Troponin T. During follow up 28 cardiac events were recorded. Troponin T had a significantly higher specificity, positive predictive value and proportion of correct prediction for cardiac events within 6 months compared to creatine kinase MB.

CONCLUSIONS

Troponin T has proved to be an useful method for diagnosing myocardial damage in routine clinical use in the non-trauma emergency department.

Intravenous immunoglobulin application following immunoadsorption: benefit or risk in patients with autoimmune diseases?

OBJECTIVE

To evaluate infection rates, side-effects and autoantibody resynthesis after immunoadsorption with and without intravenous immunoglobulin substitution.

METHODS

Thirty-five patients with autoimmune diseases who were on long-term immunoadsorption therapy participated in a prospective, randomized study. Results and conclusions. Infections were rare but similar in frequency in patients receiving combined immunoadsorption and intravenous immunoglobulins (intervention group, n=17, 1.3 infections per patient-year) and in a control group (n=18, 0.9 infections per patient-year) treated by immunoadsorption alone. The reduction in IgG achieved with two immunoadsorptions within 3 days was 95.0+/-2.5%. The extent of removal of pathogenic autoantibodies was similar to the removal of IGG: Substitution of immunoglobulins was not associated with an increased circulating IgG level before the following immunoadsorption. Infusion of immunoglobulins at a dose of 0.14 g/kg (interquartile range 0.12-0.16) body weight in patients in whom circulating immunoglobulins had been depleted was associated with a high incidence of serious side-effects; these necessitated the termination of treatment in 24% of the patients. No evidence was found that immunoglobulin administration had any beneficial effect with respect to autoantibody resynthesis after immunoadsorption.

Bone turnover markers and sex hormones in men with idiopathic osteoporosis

BACKGROUND

In contrast to osteoporosis in postmenopausal women, osteoporosis in men has received much less attention.

PATIENTS AND METHODS

We determined various biochemical parameters of bone metabolism and sex hormones in 31 men with idiopathic osteoporosis and 35 age matched control subjects.

RESULTS

In the men with osteoporosis, a significantly increased urinary excretion of deoxypyridinoline (5.3 +/- 0.2 vs. 4.6 +/- 0.2 nmol mmol-1 creatinine; P = 0.033) in addition to increased serum levels of the c-terminal telopeptide of type I collagen (2677 +/- 230 vs. 2058 +/- 153 pmol; P = 0.037) were found. While parameters of bone formation were not significantly different in the patients and controls, serum bone sialoprotein levels were significantly decreased in the patients (3.7 +/- 0.8 vs. 12.4 +/- 4.0 ng mL-1; P = 0.021). Moreover, in men with idiopathic osteoporosis, lower levels of estradiol (91.3 +/- 5.8 vs. 114.6 +/- 7.8 pmol L-1; P = 0.044), higher levels of sex hormone binding globulin (31.5 +/- 3.1 vs. 24.2 +/- 1.4 nmol L-1; P = 0.034) and a decreased free androgen index (42.6 +/- 5.2 vs. 56.4 +/- 5.9; P = 0.016) were seen. Serum estradiol levels correlated negatively with several parameters of bone resorption.

CONCLUSIONS

In men with idiopathic osteoporosis, bone resorption is increased and exceeds bone formation. The excessive bone resorption seen in idiopathic male osteoporosis may be due to decreased estradiol levels and low levels of bioavailable testosterone.

Urinary excretion of apolipoprotein(a): relation to other plasma proteins

The atherogenic lipoprotein Lp(a) consists of an LDL-like core and apo(a), linked to apoB via a thiol bridge. Apo(a) fragments ranging in size from 60 to 220 kDa are excreted into urine and the excretion rate correlates significantly with the plasma levels of Lp(a). In order to study the interrelationship of apo(a) secretion with that of other plasma proteins, urinary apo(a) and protein secretion of five probands were followed for 24 h at different urinary densities. The excretion rate of apo(a) fragments, despite their high molecular weight, was highest, followed by apoD, orosomucoid, albumin and beta(2)-glycoprotein-I (beta2-GI) and plasminogen (1.58, 0.87, 0.095, 0.027, 0.013 and <0.001%/day, respectively). There was a highly significant correlation between apo(a), apoD and beta2-GI concentrations but not with albumin and orosomucoid concentrations in urine. The only protein that was fragmented in urine was apo(a) while the other proteins had molecular weights comparable to those in plasma. We conclude that a previously suggested fragmentation of apo(a) by the kidney is not a rate-limiting step in its excretion. Since plasminogen, another kringle-IV-containing plasma compound, and fragments thereof, are undetectable in urine under identical experimental conditions, it is very unlikely that the characteristic kringle structure is responsible for the high excretion rate of apo(a).