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M L Sanz

Publications and source records attributed to M L Sanz.

At least 19 recordsLinked to original sources
PubMed2006

Development of a robust method for the quantitative determination of disaccharides in honey by gas chromatography.

An iterative method for the GC quantitative determination of TMS-oxime disaccharides in honey has been developed. This approach takes into account possible positive systematic errors caused by unidentified compounds which overlap with the expected disaccharides. The results of its application to the determination of 15 disaccharides in simulated honey samples indicate that the iterative method is more robust that methods based on least-squares regression, improves the accuracy of the quantitative analysis and allows to detect the possible presence of disaccharides not identified.

Chromatography, Gas↗
PubMed2006

Hypersensitivity to aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs).

Hypersensitivity to aspirin and other non steroidal anti-inflammatory drugs (NSAIDs) manifesting in the airways (rhinosinusitis, polyps, asthma) or in the skin (urticaria, angioedema) is the second most frequent untoward allergic reaction to drugs. Various aspects of this syndrome, such as its clinical features, the cell types and mediators involved, the role of underlying chronic inflammatory processes, the patterns of cross-reactivity between NSAIDs, the major role of sulfidoleukotrienes (LTC4) and of some other mediators such as prostaglandin E2 (PGE2) and C5a are briefly reviewed. It has been assumed for a long time that there were no reliable in vitro tests for that condition and that diagnostic confirmation can only be ascertained by provocation challenge. This appears no longer to be true, since several recent studies using a leukotriene release test (CAST) or a basophil activation test (BAT) on blood basophils, or a combination of both tests, yields positive results (70-75%) in a sizeable number of clinically validated cases, with a high specificity (above 85%). The finding in that syndrome of hyperreactive basophils suggests that the NSAID hypersensitivity syndrome is due to the associated effect of several factors: 1) Localized inflammatory processes causing a non specific cellular hyperreactivity; 2) An abnormal pharmacogenetic reaction to NSAIDs resulting in a hyperproduction of LTC4 and other mediators by activated mast cells, basophils and eosinophils.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2005

Specific IgG to Thermoactynomices vulgaris, Micropolyspora faeni and Aspergillus fumigatus in building workers exposed to esparto grass (plasterers) and in patients with esparto-induced hypersensitivity pneumonitis.

BACKGROUND: Esparto is one the most frequent causes of hypersensitivity pneumonitis in Spain. OBJECTIVE: Determination of risk factors in the working environment that could explain the sensitisation process, and assessment of the differences in specific IgG levels to Aspergillus fumigatus, Saccharopolyspora rectivirgula and Thermoactynomices vulgaris in patients with hypersensitivity pneumonitis induced by esparto, exposed healthy plasterers and control population. METHODS: Determination of precipitins and specific IgG to Aspergillusfumigatus, Saccharopolyspora rectivirgula and Thermoactynomices vulgaris in the three previously mentioned groups. Questionnaire on possible risk occupational and extra-occupational factors. RESULTS: Both healthy and exposed plasterers have higher levels of specific IgG to Aspergillus fumigatus, Saccharopolyspora rectivirgula and Thermoactynomices vulgaris than the healthy controls. The patients had higher levels of IgG than exposed healthy plasterers only to Thermoactynomices vulgaris. Precipitins were detected in only two patients. There were no occupational factors influencing on the sensitisation process. CONCLUSIONS: Specific IgG is an occupational exposure marker among plasterers, but it has not been possible to establish a cut off point that differentiates exposed subjects from affected ones. This determination has a greater sensitivity than precipitins. We did not identify occupational or extra-occupational risk factors that facilitate the sensitisation process.

Adult↗
PubMed2005

Antigen specific quantification of sulfidoleukotrienes in patients allergic to Betalactam antibiotics.

BACKGROUND: After in vitro allergen-specific stimulation, basophils become activated and release sulfidoleukotrienes LTC4, LTD4 and LTE4. This can be detected by means of the CAST assay. We assessed the positivity criteria and the reliability of antigen-specific sulfidoleukotriene production (CAST) in the in vitro diagnosis of betalactam (BL) allergic patients. MATERIAL AND METHODS: We studied a sample of 67 patients (age 48.94 +/- 15.76 years) who had presented with anaphylaxis or urticaria-angioedema within the first 60 minutes after administration of Amoxicillin (54/67), Penicillin G (7/67), Cefuroxime (5/67) or Cefazoline (1/67). All of them had a positive skin test to at least one of the antigenic determinants of Penicillin. As control group 30 adults with negative skin tests who tolerated BL were included. All of them underwent skin tests, oral provocation tests, specific IgE (CAP-FEIA, Pharmacia) and CAST. RESULTS: Positivity criteria were established by means of ROC curves: a sLT release induced by Betalactams of at least 100 pg/ml and greater than or equal to 3 times the basal value. The overall sensitivity of CAST is 47.7% and specificity 83.3%. Sensitivity of specific IgE is 37.8% and specificity 83.3%. CONCLUSIONS: We have established validated positivity criteria for the CAST technique in patients allergic to Betalactams. This technique is a useful in vitro diagnostic method in patients with IgE-mediated allergy to Betalactam antibiotics.

Amoxicillin↗
PubMed2005

Hydrochlorothiazide-induced acute non-cardiogenic pulmonary edema.

We report the case of a 64 year-old male with non cardiogenic pulmonary edema episodes after oral administration of 12.5 mg of hydrochlorothiazide. In vitro immunologic study with basophil activation test and late cellular activation study (CD69 and production of interferon gamma) with chlorothiazide were performed, and no activation was observed. As a consequence, like in previous cases published, the pathogenic mechanism remains unknown, and it probably is an idiosyncratic reaction.

Antihypertensive Agents↗
PubMed2005

Latex-vegetable syndrome due to custard apple and aubergine: new variations of the hevein symphony.

An increasing number of vegetables with crossreactions to latex are being described in patients with latex-vegetable syndrome. We present two of these vegetables, custard apple linked in two previous cases with latex sensitisation, and aubergine, that had not been described up to now in patients with latex sensitisation. The diagnosis of both cases was based on the clinical history, positive skin prick test (SPT) and specific IgE to the offending vegetables, as well as to positive SPT and specific IgE levels to latex and the major fruits involved in the latex-fruit syndrome (avocado, banana, and chestnut). Further, crude extracts from latex, custard apple and aubergine, as well as the purified allergens Hev b 6.02 and Prs a 1 were used in in vitro and in vivo assays: IgE immunodetection, histamine release (HRT) and basophil activation (BAT) tests and skin prick tests. In case 1, both purified Hev b 6.02 and Prs a 1 induced positive responses in skin prick tests, high levels of basophil activation and histamine release. Specific IgE immunodetection uncovered a reactive band of 45 kd in the crude custard apple extract, which was also recognized by anti-chitinase monospecific antibodies. The serum from patient 1 also detected Prs a 1 in immunodetection. Hev b 6.02 produced positive skin responses and showed high biological activity in HRT and BAT in the case of patient 2. However, Prs a 1 was reactive neither in SPT nor in IgE immunodetection. In fact, no band was detected using the serum of patient 2 in avocado or aubergine extracts. By contrast, Prs a 1 reached high values of basophil activation and over 10% of histamine release in case 2.

Adult↗
PubMed2004

A new combined test with flowcytometric basophil activation and determination of sulfidoleukotrienes is useful for in vitro diagnosis of hypersensitivity to aspirin and other nonsteroidal anti-inflammatory drugs.

BACKGROUND: We assessed whether nonsteroidal anti-inflammatory drugs (NSAIDs) may provoke blood basophil activation in vitro in aspirin- and NSAID-hypersensitive patients, as detected by a flowcytometric technique using the CD63 marker--flowcytometric basophil activation test (FAST) assay--in addition to the sulfidoleukotriene (sLT) release--the cellular allergen stimulation test (CAST). METHODS: Sixty aspirin- and/or NSAID-hypersensitive patients were studied. Thirty control patients without history and negative provocation challenge were also included. The percentage of activated basophils after in vitro stimulation with NSAIDs at 3 different concentrations was evaluated by an anti-CD63 phycoerythrin conjugate (FAST assay) and the amount of sLTs released in the cell supernatant by ELISA (CAST assay). RESULTS: For aspirin, the FAST indicated a sensitivity of 41.7%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value of 99.4%; for paracetamol 11.7 and 100%, for metamizol 15 and 100%, for diclofenac 43.3 and 93.3%, and for naproxen 54.8 and 74.1%. Many patients showed positive tests to more than 1 NSAID. When considering the first 4 NSAIDs, the global sensitivity increased to 66.7%, while the specificity remained at 93.3%. The addition of the CAST results still increased the sensitivity up to 73.3%, but with a decrease of the specificity to 71.4%. CONCLUSIONS: The FAST shows a high percentage of positive reactions, which may reach 60-70% when 4 NSAIDs are tested and even 88% when the test is performed within 1 month of the last clinical drug exposure and reaction. The test has a high specificity above 90%. The addition of sLT determinations yields additional information in a few isolated cases. It is suggested that this test, when properly used, may help avoid some cumbersome and dangerous provocation challenges.

Adult↗
PubMed2004

Gas chromatographic-mass spectrometric method for the qualitative and quantitative determination of disaccharides and trisaccharides in honey.

An improved method has been developed to identify and quantify honey disaccharides and trisaccharides by gas chromatography and mass spectrometry. The procedure, based on mass spectral and retention data ("retention time windows") determined on two capillary columns with different stationary phases allowed the identification and quantitation in honey of 16 disaccharides and 9 trisaccharides, some of which were not previously identified by GC. The reliability of the analytical results was considerably improved by the use of this procedure: several unidentified disaccharides and trisaccharides were detected, and their presence was taken into account in the quantification.

Disaccharides↗
PubMed2004

Biological characterization of glutaraldehyde-modified Parietaria judaica pollen extracts.

BACKGROUND: Allergoids are widely used in specific immunotherapy (SIT) for the treatment of IgE-mediated allergic diseases, but all techniques for standardization of conventional allergic extracts may not be appropriate for standardization of a glutaraldehyde (GA)-modified extract because of the unique characteristics of these extracts. OBJECTIVE: To assess an accurate methodology for standardization of chemically modified extracts. METHODS: GA-modified extracts from Parietaria judaica pollen were purified by diafiltration. Biochemical properties were investigated by determination of amino groups, chromatography, and SDS-PAGE. The IgE-binding activity was determined by skin prick test, enzyme allergosorbent test inhibition, basophil activation, and histamine release tests. Peripheral blood mononuclear cells (PBMCs) from P. judaica pollen-allergic subjects were stimulated with either native or allergoid extracts, and proliferation was measured. RESULTS: Biochemical data indicated a high degree of allergen polymerization resulting in extract components higher than 100 kDa. IgE-binding activity, both in vivo and in vitro, was reduced by more than 99.8%. Both allergen and allergoid induced PBMC proliferation and synthesis of blocking IgG antibodies at similar rates. Moreover, no evidence of introduction of new determinants by chemical modification was found. CONCLUSIONS: The preparation of GA-modified extracts by diafiltration is faster and more reliable than previous chromatographic methods. These modified extracts have drastically reduced their allergenicity while maintaining their immunogenicity, and therefore they can be used in safer and shortened schedules of SIT.

Adolescent↗
PubMed2004

The flow-cytometric determination of basophil activation induced by aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) is useful for in vitro diagnosis of the NSAID hypersensitivity syndrome.

BACKGROUND: Hypersensitivity reactions to non-steroidal anti-inflammatory drugs (NSAIDs), manifested by cutaneous symptoms and/or airway manifestations represent 20-25% of all hypersensitivity reactions to drugs. Today, it is still claimed that no in vitro diagnostic tests exist for that condition and that the only way to confirm the diagnosis is a provocation challenge. OBJECTIVE: The objective of this study was to assess whether NSAIDs may provoke blood basophil activation in vitro in such patients, as detected by a flowcytometric technique. METHODS: Sixty NSAID hypersensitive patients (38 with cutaneous, 20 with airway and two with cutaneous and airway symptoms) and 30 control patients (15 asthmatics) were selected. Their hypersensitivity was confirmed by documented history indicating at least two clinical episodes to two or more different NSAIDs or by positive oral provocation challenge. Isolated buffy coat leukocytes were stimulated in vitro with aspirin, paracetamol, metamizol, diclofenac, and naproxen. The percentage of activated basophils was evaluated by an anti-CD63. RESULTS: Aspirin showed a sensitivity of 43.3%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value of 99.4%. For the other NSAIDs, the sensitivity and specificity values were: for paracetamol 11.7% and 100%, for metamizol 15% and 100%, for diclofenac 43.3% and 93.3% and for naproxen 54.8% and 74.1%. When considering the first four NSAIDs, the global sensitivity raised to 63.3% and specificity to 93.3%. If the number of tests is to be limited for practical reasons, the combination of acetylsalicylic acid and diclofenac at two concentrations yields a sensitivity of 58.3% and a specificity of 93.3%. CONCLUSIONS: Flowcytometric determinations of basophil activation following stimulation with NSAIDs show a high sensitivity (60-70%) with specificity above 90%. So this test may help avoiding some cumbersome and dangerous provocation challenges.

Acetaminophen↗
PubMed2004

Cellular allergen stimulation test (CAST) 2003, a review.

Specific diagnosis of immediate type allergies, such as rhinoconjunctivis, asthma, urticaria/angioedema and anaphylaxis, particularly when IgE-mediated, traditionally rests on prick and/or intradermal skin tests and, since about 30 years, on the determination of allergen specific IgEs. Some cellular tests, i.e. tests determining the reactivity of blood cells in vitro, particularly basophils, to allergens, have been available for many years. The determination of histamine release has been widely used in allergy pathophysiological research but its routine application in allergy diagnosis has been restricted to few groups. Basophil degranulation, as determined by microscopic examination, was promoted by some groups in the 1980's but has been largely abandoned since around 10 years ago; an alternative cellular test, based on the determination of sulfidoleukotrienes (LTC4, LTD4, LTE4) produced by IL-3 primed basophils stimulated by allergens in vitro, has been proposed. This test became available commercially in 1993 under the name of CAST (Bühlmann Laboratories, Allschwil, Switzerland). The CAST assay has been used in allergy diagnosis in a variety of indications, such as inhalation allergies, allergies to insect venoms, foods, occupational allergens and various drugs. A large number of reports on CAST diagnostic value, however, have been anecdotal. A meta-analysis of validated and well controlled studies encompasses 37 studies, 1614 patients and 1145 controls. This should definitely establish the value of this diagnostic test, particularly in instances where other in vitro or in vivo diagnostic tests are not reliable, such as food or drug allergies, as well as in non-IgE-mediated immediate hypersensitivity reactions. However, a number of questions about the CAST diagnostic assay are still open or have not been systematically explored. This may explain, in addition to the practical limitations inherent to all allergy cellular tests, why CAST has not yet become a very widely used assay worldwide, having gained broad acceptance in some countries but not in others.

Allergens↗
PubMed2004

Basophil activation and sulfidoleukotriene production in patients with immediate allergy to betalactam antibiotics and negative skin tests.

BACKGROUND: New in vitro diagnostic methods for IgE-mediated drug allergic reactions, such as basophil activation test and antigen specific sulfidoleukotriene test, have proven their usefulness in patients with positive skin tests. OBJECTIVE: To assess the usefulness of basophil activation test and antigen specific sulfidoleukotriene test in the diagnosis of patients with IgE-mediated allergy to Betalactam antibiotics and negative skin tests. METHODS: The 23 patients included in the study underwent basophil activation test, antigen specific sulfidoleukotriene test and specific IgE. The patients were classified into three groups. GROUP A: patients with positive specific IgE. GROUP B: patients with a unique immediate reaction to Betalactams, negative specific IgE and positive oral provocation tests. And Group C: patients with at least two immediate reactions induced by Betalactams and negative specific IgE. RESULTS: The sensitivity/specificity of the different tests are: basophil activation test 39.1 %/93.3%, antigen specific sulfidoleukotriene test 22.7%/83.3%, specific IgE 21.7%/86.7%. The joint use of the three tests allows diagnosis of 60.9% of the patients. CONCLUSION: In vitro diagnostic tests, especially basophil activation test, are very important tools in the diagnosis of patients with IgE-mediated allergy to Betalactams and negative skin tests, avoiding performance of potentially dangerous oral provocation tests in a high percentage of cases.

Adult↗
PubMed2003

Use of CD63 expression as a marker of in vitro basophil activation and leukotriene determination in metamizol allergic patients.

BACKGROUND: We assessed the reliability of basophil activation test (FAST) and sulphidoleukotriene production (CAST) in the in vitro diagnosis of allergy to metamizol, evaluating its sensitivity and specificity. METHODS: Twenty-six patients allergic to metamizol and 30 control individuals were studied. Skin tests with metamizol, FAST, and CAST were performed. RESULTS: FAST sensitivity was 42.3% and specificity 100%. The PPV of FAST is 100% and the NPV 99.4%. The likelihood ratio for a positive value cannot be calculated because the specificity is 100% and the likelihood ratio for a negative value is 0.58. CAST sensitivity was 52%, and specificity 90%. The PPV of the test is 5% and the NPV 99.5%. The likelihood ratio for a positive result was 5.2 and that for a negative result 0.53. FAST detects a larger number of cases when patients are studied within the first 6 months after the clinical reaction (chi = 4.2, P = 0.04) than later. Together with skin tests, FAST allowed detection of 69.2% patients allergic to metamizol, the same as CAST 76%. The joint use of the three techniques allowed identification of 76.9% of cases. CONCLUSIONS: FAST and CAST are useful for the diagnosis of allergy to pyrazolones. Its usefulness clearly increases when recent reactions are studied.

Adult↗
PubMed2003

GC Behavior of disaccharide trimethylsilyl oximes.

Twenty-five disaccharides are converted to trimethylsilyl oximes and injected on two capillary columns of different polarities (methyl and phenyl-methyl silicone). Their Kovats retention indices are determined at three temperatures. Multivariate data analysis is used in order to obtain relations between retention and some structural features. Phenylmethyl silicone have better chromatographic characteristics for the assayed compounds. The two columns can provide useful chromatographic information when a very complex disaccharide mixture has to be analyzed.

Journal Article↗
PubMed2003

[Basophil activation test in the diagnosis of allergy to medicines].

In this paper we study the reliability of the basophil activation test (BAT) in the "in-vitro" diagnosis of allergy to betalactams and to metamizol, and the sensitivity and specificity of the technique are analyzed. To this end, we studied 58 patients allergic to betalactam antibiotics with a positive cutaneous test facing any derivative of penicillin and 30 healthy controls who tolerated betalactams, and 26 patients allergic to metamizol with an immediate reaction and 30 healthy controls who tolerated the medicine. Sensitivity to BAT in allergy to betalactams was 52.8%, and specificity was 92.6%. For metamizol, sensitivity was 42.3% and specificity was 100%. The positive predictive value of BAT in allergy to betalactams was 18.9% and the negative predictive value was 98.4%. For metamizol, the positive predictive value of the technique was 100% and the negative predictive value was 99.4%. The joint use of BAT and CAP (specific IgE) makes it possible to diagnose some 65% of patients allergic to betalactams. The combined use of cutaneous tests and BAT in allergy to metamizol detects 70% of the cases. BAT is a useful, non-invasive technique in the "in-vitro" diagnosis of allergy to betalactams and metamizol.

Basophil Degranulation Test↗
PubMed2002

Flow cytometric basophil activation test by detection of CD63 expression in patients with immediate-type reactions to betalactam antibiotics.

BACKGROUND: In this study, we used flow cytometry to determine the percentage of activated basophils that expressed the CD63 marker after in vitro stimulation by different betalactam antibiotics. The diagnostic reliability of the technique was assessed, as well as its correlation with specific IgE. METHODS: Fifty-eight patients with clinical allergy to betalactam antibiotics and presenting positive skin tests to at least one of the allergens (minor determinant mixture (MDM), benzylpenicilloyl-polylysine (PPL), penicillin, ampicillin, amoxicillin, cephalosporins) were tested. Thirty subjects non-allergic to betalactams were also studied as controls. The flow assay stimulation test (FAST) uses flow cytometry to determine the percentage of basophils that express CD63 as an activation marker after in vitro stimulation with allergen. Double labelling with monoclonal antibodies anti-CD63-PE and anti-IgE FITC was used. RESULTS: The allergic patients show a statistically greater number of activated basophils than the control subjects, after the incubation of cells with all the betalactams at various concentrations. The sensitivity of the technique is 50%, the specificity 93.3%, the likelihood ratio for a positive value 7.46 and the likelihood ratio for a negative value 0.54. In spite of having a greater sensitivity (37.9%) and specificity (86.7%) than CAP, differences between sensitivity and specificities of both techniques (CAP and FAST) do not reach statistical significance. CONCLUSION: The basophil activation test is a particularly useful technique in the diagnosis of patients with IgE-mediated allergy to betalactams and allows the identification of 50% of patients. Used in conjunction with CAP, it allows the identification of 65.5% of such patients.

Adult↗