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M L Baeza

Publications and source records attributed to M L Baeza.

43 records · Page 3Linked to original sources

Prevalence and functional role of anti-IgE autoantibodies in urticarial syndromes.

The prevalence of autoantibodies of immunoglobulin G (IgG) and immunoglobulin M (IgM) classes directed against myeloma immunoglobulin E (IgE) were determined in distinct subsets of urticaria, using an enzyme immunoassay. IgG anti-IgE antibodies were found in five of nine patients (55%) with cold urticaria, four of eight patients (50%) with urticarial vasculitis, and three of six patients (50%) with chronic urticaria. IgM anti-IgE antibodies were found exclusively in cold urticaria (two of nine patients, 22%). Heating of these sera increased the binding to IgE, suggesting immune complex formation. Several positive sera were capable of inducing histamine release from normal peripheral basophils and caused a wheal-flare response upon intradermal injection. Sera containing such autoantibodies from three cold urticaria patients were studied for passive transfer of cold sensitivity. One serum containing IgG anti-IgE gave a strongly positive transfer test at 5 h but not 48 h, suggesting a pathogenic role for the IgG.

Antibodies, Anti-Idiotypic↗

Human recombinant granulocyte-macrophage colony-stimulating factor and interleukin 3 cause basophil histamine release.

Histamine-releasing factors (HRFs) have been shown to be released from a variety of human cells, including T lymphocytes and alveolar macrophages. We considered the possibility that known cytokines might possess such activity on human basophils and/or mast cells and therefore tested preparations of human recombinant IL 3, IL 4, IL 5, granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) upon a panel of basophil donors. IL 3 and GM-CSF possessed significant histamine-releasing activity in 8 of 10 and 12 of 14 subjects, respectively. In each instance, a dose response could be demonstrated. IL 4 and G-CSF had no such activity, whereas IL 5 had activity in only 2 of 14 donors tested. We conclude that IL 3 and GM-CSF represent two effective HRFs, and suggest that HRF, as isolated based upon histamine-releasing activity, is likely to be heterogeneous in terms of molecular identity. Whether previously described HRFs relate specifically to IL 3 or GM-CSF must await primary sequence analysis of HRF and/or studies with monospecific antisera.

Basophils↗

Anaphylactic shock caused by impurities in orgotein preparations.

Previously reported allergic reactions to orgotein (superoxide dismutase) injections has assigned responsibility to this molecule, which is obtained from bovine liver. We report an anaphylactic shock probably caused by impurities contained in an orgotein preparation. Prick test to Peroxinorm (orgotein), BSA, and cow liver extract were positive but resulted negative with chymotrypsin, milk, meat and cow epithelium extracts. Tryptase levels determined 3, 24 hours and 15 days after the shock measured 6.32, 0.81 and 0.84 U/L respectively. Detection of specific IgE to Peroxinorm, BSA and chymotrypsin by ELISA was negative and positive to cow liver. Specific IgE to milk and cow epithelium by Pharmacia CAP system was negative. Immunoblotting with Peroxinorm revealed IgE specific bands at an apparent M.W of 67, 51, 56 and 16 kDa; immunoblotting with cow liver revealed bands at 72, 56, 50 and 36 kDa; immunoblotting with BSA and chymotypsin were negative. This case emphasises the role that 20 % of impurities of the pharmaceutical preparation may have in immediate hypersensitivity reactions.

Allergens↗

Dietary recommendations for patients allergic to Anisakis simplex.

BACKGROUND: Anisakis simplex, a fish parasite, causes allergic urticaria, angioedema and anaphylactic shock through an IgE-mediated hypersensitivity mechanism. Consensus on the dietary recommendations that should be given to allergic patients is lacking. Our objective was to evaluate the usefulness of different types of diets in preventing further reactions in patients allergic to A. simplex. METHODS: Twenty-eight adult patients, who had suffered an allergic episode caused by A. simplex were asked to follow one of the following three diets for a mean period of 13.16 months: a fish-free diet (diet 1; n = 19), a diet including fish frozen for more than 48 hours (diet 2; n = 9) and a diet with fresh fish (diet 3; n = 12). In all patients raw fish was excluded. Relapse rates and changes in total serum IgE and specific IgE to A. simplex were studied during the follow up. RESULTS: During the 13-month follow-up none of the patients developed anaphylaxis. Urticaria symptoms were present in 5.8 %, 11.1 % (n.s) and 33.3 % (p = 0.016) of patients following diets 1, 2 and 3, respectively. Total IgE decreased by 64 % (p < 0.05), 48 % (p < 0.05) and 39.4 % (p < 0.05), respectively. Specific IgE to A. simplex decreased by 50.7 % (p < 0.05), 54.1 % (p < 0.05) and 23.6 % (p < 0.05) after diets 1, 2 and 3, respectively. No statistically significant differences were found among the groups in variations in total and specific IgE. CONCLUSIONS: Patients allergic to A. simplex can eat fish that has been frozen at -20 C for 48 hours without risk of a severe allergic reaction. Long term decreases in specific and total IgE may not be good markers of eventual contact with A. simplex.

Adult↗

Is Anisakis simplex responsible for chronic urticaria?

The association of chronic urticaria (CU) to parasitic infestations has been poorly studied. Recently, sensitization to the parasite larva Anisakis simplex has been described as the cause of acute urticaria and anaphylaxis. The aim of this work was to study the relationship between sensitization to A. simplex and CU. One hundred one patients with CU were studied. Data of possible contacts with A. simplex were collected and the usual CU study was performed. Furthermore, total and specific immunoglobulin E (IgE; Pharmacia CAP system IGE fluorescence enzyme immunoassay: CAP) to A. simplex, Ascaris lumbricoides, Echinococcus granulosus, and Toxocara canis were determined as well as skin-prick test with A. simplex and serology to E. granulosus. In accordance with the results of the CAP to A. simplex, the patients were divided into two groups, positive and negative, and, subsequently, subdivided into two other subgroups that were alternatively told to stop eating fish or seafood in their diet or to continue with their normal diet. Checkups were performed at 6, 12, and 18 months. Thirty-five percent of the patients had positive skin tests to A. simplex, and CAP to A. simplex was positive in 55%. The fish-eating habits, acute or chronic gastrointestinal disease, and the background of abdominal surgery were not related to the results of the CAP and/or skin test to A. simplex. A total of 21.8% of all the patients had detectable CAP to A. lumbricoides, 91% of whom had positive CAP to A. simplex. Three patients had specific IgE to T. canis and five patients had specific IgE to E. granulosus, in the absence of positive serology. All had specific IgE to A. simplex. Present infestation could not be proved in any of them. The clinical evolution and variations of CAP to A. simplex and of total IgE were not statistically different among the groups during the 6, 12, and 18 months of the study. The percentage of sensitization to A. simplex in patients with CU is elevated and determines the sensitization to other parasites because of cross-reactivity. We have not found any causal relationship between the presence of specific IgE to A. simplex and CU. The clinical importance of this finding in this disease is still undetermined.

Adolescent↗

Clinical tolerance, parasitological efficacy and environmental effects of dehumidifiers in stable asthmatics sensitized to house dust mites.

Dehumidifiers (DH) are potentially effective appliances as coadjuvant therapy in the treatment of bronchial asthma caused by sensitization to house dust mites. The aims of this study were to analyze DH tolerance in asthmatic patients, to assess the parasitological effects and to analyze the environmental effects produced by the use of these appliances in the bedrooms of asthmatic patients sensitized to house dust mites. 10 stable asthmatic patients sensitized to house dust mites were studied. DH appliances (CD-300) were installed in their bedrooms. Each patient was given symptom scoring tables and a portable peak expiratory flow (P.E.F.) during a period of 5 months, 1 month before installing the DH and 4 months afterwards. To study the parasitological efficacy of the DHs, we analyzed dust samples from the bedrooms and determined the Der p I, Der f I and Der II allergens by means of a modified ELISA based on monoclonal antibodies. Dust samples were collected before installing the DHs and after they had been working for 2 and 4 months. Dry temperature and relative humidity measurements at three time intervals (7-9, 15-17 and 22-24 h) were carried out. The 1st measurement was done prior to installation of the DHs in the patients' bedrooms and the 2nd and 3rd were achieved 2 and 4 months respectively after the installation. Statistical analysis was done by comparison of paired means. No significant differences were detected in the patients' symptoms nor in the P.E.F. measurements in the course of the study. Decreases in the house dust mite allergens were observed in 4 bedrooms. A significant decrease in relative humidity in the bedrooms of mite asthma patients after use of dehumidifier appliances was observed (p < 0.01). Significant differences between the measurements of the bedrooms with and without DH were detected (p < 0.01). In summary, DHs were well tolerated by stable asthmatic patients, produced a significant decrease in the relative humidity level and showed some parasitological efficacy.

Animals↗

Acute IgE-mediated generalized urticaria-angioedema after topical application of povidone-iodine.

Povidone is a synthetic polymer mainly used as a dispersing or suspending agent for many pharmaceutical products. It is also used as a carrier for iodine. In many countries it is not mandatory its inclusion in drug labels so many adverse effects may be under diagnosed. Povidone-iodine used as a topical antiseptic solution may produce allergic contact dermatitis and irritation. Povidone, when systemically administered may deposit in tissues causing local lesions and pain. Three cases of immediate hypersensitivity to this agent have been reported. We present a patient who developed generalized urticaria and angioedema immediately after the first topical use of Betadine (povidone-iodine) on a right arm wound. The positive skin prick test to Betadine and povidone extract and the demonstration of serum specific IgE to povidone, confirmed an IgE-mediated hypersensitivity.

Acute Disease↗