[Cross allergy between penicillins and other beta lactam antibiotics--the risk is much less than previously thought]. / Korsallergi mellan penicilliner och övriga betalaktam-antibiotika - Risken är betydligt mindre än man tidigare trott.

Severe IgE-mediated allergic reactions to penicillins are rare but might be fatal. Because some studies demonstrated a high risk of cross-sensitivity to cephalosporins and carbapenems it has been recommended to avoid these antibiotics in patients with suspected hypersensitivity to penicillins. However, recent studies and analyses conclude that the risk of cross-reactivity was overestimated in the earlier studies and that it is in fact very low for parenteral cephalosporins and perhaps even negligible for carbapenems. The new knowledge has implications for the choice of therapy for bacterial infections in patients with a history of penicillin hypersensitivity, because alternative antibiotic regimens are often inferior to beta-lactam antibiotics. The aim of the present review is to present existing knowledge on cross-sensitivity between beta-lactams, as well as to discuss the management of patients with suspected allergic reactions to these antibiotics.

Does allergen-specific immunotherapy induce contact allergy to aluminium?

Persistent, itching nodules have been reported to appear at the injection site after allergen-specific immuno-therapy with aluminium-precipitated antigen extract, occasionally in conjunction with contact allergy to aluminium. This study aimed to quantify the development of contact allergy to aluminium during allergen-specific immunotherapy. A randomized, controlled, single-blind multicentre study of children and adults entering allergen-specific immunotherapy was performed using questionnaires and patch-testing. A total of 205 individuals completed the study. In the 3 study groups all subjects tested negative to aluminium before allergen-specific immunotherapy and 4 tested positive after therapy. In the control group 4 participants tested positive to aluminium. Six out of 8 who tested positive also had atopic dermatitis. Positive test results were found in 5/78 children and 3/127 adults. Allergen-specific immunotherapy was not shown to be a risk factor for contact allergy to aluminium. Among those who did develop aluminium allergy, children and those with atopic dermatitis were more highly represented.

Icatibant, a new bradykinin-receptor antagonist, in hereditary angioedema.

BACKGROUND: Hereditary angioedema is characterized by recurrent attacks of angioedema of the skin, larynx, and gastrointestinal tract. Bradykinin is the key mediator of symptoms. Icatibant is a selective bradykinin B2 receptor antagonist. METHODS: In two double-blind, randomized, multicenter trials, we evaluated the effect of icatibant in patients with hereditary angioedema presenting with cutaneous or abdominal attacks. In the For Angioedema Subcutaneous Treatment (FAST) 1 trial, patients received either icatibant or placebo; in FAST-2, patients received either icatibant or oral tranexamic acid, at a dose of 3 g daily for 2 days. Icatibant was given once, subcutaneously, at a dose of 30 mg. The primary end point was the median time to clinically significant relief of symptoms. RESULTS: A total of 56 and 74 patients underwent randomization in the FAST-1 and FAST-2 trials, respectively. The primary end point was reached in 2.5 hours with icatibant versus 4.6 hours with placebo in the FAST-1 trial (P=0.14) and in 2.0 hours with icatibant versus 12.0 hours with tranexamic acid in the FAST-2 trial (P<0.001). In the FAST-1 study, 3 recipients of icatibant and 13 recipients of placebo needed treatment with rescue medication. The median time to first improvement of symptoms, as assessed by patients and by investigators, was significantly shorter with icatibant in both trials. No icatibant-related serious adverse events were reported. CONCLUSIONS: In patients with hereditary angioedema having acute attacks, we found a significant benefit of icatibant as compared with tranexamic acid in one trial and a nonsignificant benefit of icatibant as compared with placebo in the other trial with regard to the primary end point. The early use of rescue medication may have obscured the benefit of icatibant in the placebo trial. (Funded by Jerini; ClinicalTrials.gov numbers, NCT00097695 and NCT00500656.)

Ancient recruitment by chromists of green algal genes encoding enzymes for carotenoid biosynthesis.

Chromist algae (stramenopiles, cryptophytes, and haptophytes) are major contributors to marine primary productivity. These eukaryotes acquired their plastid via secondary endosymbiosis, whereby an early-diverging red alga was engulfed by a protist and the plastid was retained and its associated nuclear-encoded genes were transferred to the host genome. Current data suggest, however, that chromists are paraphyletic; therefore, it remains unclear whether their plastids trace back to a single secondary endosymbiosis or, alternatively, this organelle has resulted from multiple independent events in the different chromist lineages. Both scenarios, however, predict that plastid-targeted, nucleus-encoded chromist proteins should be most closely related to their red algal homologs. Here we analyzed the biosynthetic pathway of carotenoids that are essential components of all photosynthetic eukaryotes and find a mosaic evolutionary origin of these enzymes in chromists. Surprisingly, about one-third (5/16) of the proteins are most closely related to green algal homologs with three branching within or sister to the early-diverging Prasinophyceae. This phylogenetic association is corroborated by shared diagnostic indels and the syntenic arrangement of a specific gene pair involved in the photoprotective xanthophyll cycle. The combined data suggest that the prasinophyte genes may have been acquired before the ancient split of stramenopiles, haptophytes, cryptophytes, and putatively also dinoflagellates. The latter point is supported by the observed monophyly of alveolates and stramenopiles in most molecular trees. One possible explanation for our results is that the green genes are remnants of a cryptic endosymbiosis that occurred early in chromalveolate evolution; that is, prior to the postulated split of stramenopiles, alveolates, haptophytes, and cryptophytes. The subsequent red algal capture would have led to the loss or replacement of most green genes via intracellular gene transfer from the new endosymbiont. We argue that the prasinophyte genes were retained because they enhance photosynthetic performance in chromalveolates, thus extending the niches available to these organisms. The alternate explanation of green gene origin via serial endosymbiotic or horizontal gene transfers is also plausible, but the latter would require the independent origins of the same five genes in some or all the different chromalveolate lineages.

The establishment and utility of Sweha-Reg: a Swedish population-based registry to understand hereditary angioedema.

BACKGROUND: The importance of acquiring comprehensive epidemiological and clinical data on hereditary angioedema has increasingly caught the attention of physicians and scientists around the world. The development of networks and creation of comprehensive policies to improve care of people suffering from rare diseases, such as hereditary angioedema, is a stated top priority of the European Union. Hereditary angioedema is a rare disease, that it may be life-threatening. Although the exact prevalence is unknown, current estimates suggest that it is 1/10,000-1/150,000 individuals. The low prevalence requires combined efforts to gain accurate epidemiological data on the disease and so give us tools to reduce morbidity and mortality, and improve quality of life of sufferers. METHODS: Sweha-Reg is a population-based registry of hereditary angioedema in Sweden with the objectives of providing epidemiological data, and so creates a framework for the study of this disease. The registry contains individual-based data on diagnoses, treatments and outcomes. CONCLUSION: The present manuscript seeks to raise awareness of the existence of Sweha-Reg to stimulate the international collaboration of registries. A synthesis of data from similar registries across several countries is required to approach an inclusive course understanding of HAE.

Influence of the Priming Effect with Alder Pollen on Nonspecific Bronchial Hyperreactivity of Asthmatics Specifically Allergic to Birch Pollen.

It has been shown that bronchial hyperreactivity in asthmatics specifically allergic to birch pollen is stable during the preseasonal and postseasonal periods and increases during the birch pollen season. Between January and March 1989, warm weather in the southern part of Sweden led to an early emission of hazel and alder pollens. Fourteen asthmatic patients living there were followed and demonstrated an increased nonspecific bronchial hyperreactivity (decreased PC20 methacholine) before the birch pollen season due to a 'priming effect' of related tree pollens.