IgE-mediated allergic reactions after the first administration of glatiramer acetate in patients with multiple sclerosis.

BACKGROUND: Immediate adverse reactions to glatiramer acetate (GA), a drug used in the treatment of patients with multiple sclerosis (MS), have been poorly investigated. We studied 3 MS patients who presented adverse reactions following GA administration. Two of them experienced severe anaphylactic reactions after the first administration and the other an eyelid edema upon reintroduction 6 months after GA withdrawal. METHODS: Skin prick tests (SPT) to GA and mannitol were performed on all 3 patients and in 10 atopic controls. Specific IgE (sIgE) levels to GA, myelin basic protein (MBP) and MBP fragments were assessed in all 3 patients, 6 MS patients treated with GA for more than 6 month and 10 healthy donors. Specific IgG (sIgG) to GA was also quantified in the three study groups. Both sIgE and sIgG were determined by means of the UniCAP 100 assay. RESULTS: SPT and sIgE to GA were positive only in the 3 patients with adverse reactions while sIgE to mannitol was negative in all. sIgE tests against MBP and its fragments were negative in all individuals. Similar levels of sIgG to GA were found in all studied subjects. CONCLUSION: These results demonstrate the significance of sIgE in allergic reactions to GA presented by these patients and suggest the importance of strict surveillance during administration of the first GA doses.

Effect of corticosteroids on the clinical course of community-acquired pneumonia: a randomized controlled trial.

INTRODUCTION: The benefit of corticosteroids as adjunctive treatment in patients with severe community-acquired pneumonia (CAP) requiring hospital admission remains unclear. This study aimed to evaluate the impact of corticosteroid treatment on outcomes in patients with CAP. METHODS: This was a prospective, double-blind and randomized study. All patients received treatment with ceftriaxone plus levofloxacin and methyl-prednisolone (MPDN) administered randomly and blindly as an initial bolus, followed by a tapering regimen, or placebo. RESULTS: Of the 56 patients included in the study, 28 (50%) were treated with concomitant corticosteroids. Patients included in the MPDN group show a more favourable evolution of the pO2/FiO2 ratio and faster decrease of fever, as well as greater radiological improvement at seven days. The time to resolution of morbidity was also significantly shorter in this group. Six patients met the criteria for mechanical ventilation (MV): five in the placebo group (22.7%) and one in the MPDN group (4.3%). The duration of MV was 13 days (interquartile range 7 to 26 days) for the placebo group and three days for the only case in the MPDN group. The differences did not reach statistical significance. Interleukin (IL)-6 and C-reactive protein (CRP) showed a significantly quicker decrease after 24 h of treatment among patients treated with MPDN. No differences in mortality were found among groups. CONCLUSIONS: MPDN treatment, in combination with antibiotics, improves respiratory failure and accelerates the timing of clinical resolution of severe CAP needing hospital admission. TRIAL REGISTRATION: International Standard Randomized Controlled Trials Register, ISRCTN22426306.

Quality of Life in Patients with Allergic Reactions to Medications: Influence of a Drug Allergy Evaluation.

BACKGROUND: Suspicion of allergic drug reaction can cause important disturbances in the patient's life. OBJECTIVE: We evaluated in a prospective multicenter study the quality of life of patients who suffered a possible allergic drug reaction, and analyzed the effect of a drug allergy evaluation. METHODS: Patients (>18 years old) answered the specific questionnaire twice: before the drug allergy evaluation, and 1 month after it was completed. Statistics were performed using STATA. RESULTS: A total of 360 patients (240, 66.6% female; mean age, 45.4 years; standard deviation [SD], 15.6 years) completed the first questionnaire. After the evaluation, 150 of 346 patients (43.4%) were diagnosed as allergic to the drug (115 of 150 immediate; 35 of 150 delayed) and 196 of 346 patients (56.6%) as nonallergic. The mean value of the first questionnaire was 32.14 (SD, 11.84); patients with anaphylaxis, nonanaphylactic immediate reaction, with more than 1 drug reaction, or a chronic osteoarticular disease, had a statistically significant higher score in Q0 (worse quality of life). After the allergy study, the mean of the second questionnaire was 27.27 (SD, 9.96), showing a global improvement (P < .001). No statistically significant difference was found between drug allergic and non-drug allergic patients (P = .340); however, being >40 years old (P = .030), having a chronic osteoarticular disease (P = .003) and having more than 1 reaction to drugs (P < .001) were associated with a statistically significant worse quality of life after the evaluation. CONCLUSIONS: Having suffered anaphylaxis, more than 1 reported drug allergy or presenting a musculoskeletal disease are factors that worsen the quality of life. Quality of life improved significantly after completing a drug allergy evaluation.

Immediate hypersensitivity to penicillins. Identification of a new antigenic determinant.

The study of adverse drug reactions (ADRs) constitutes a challenge in the area of Medicine. Drugs generate a large number of the total registered hypersensitivity reactions, where penicillins are responsible for more than half of them. In vitro tests in the market are not efficient enough since they lack in sensitivity and specificity. This is the reason why in vivo tests are carried out, with the subsequent danger to the patient's life. It is essential to discover new ß-lactam antigenic determinants to develop more effective detection systems and thus, obtain better explanations of the allergic mechanisms related to these drugs. We propose a strategy based on the use of "peptide probes", small labeled and chemical active peptides which have been structurally modified for reacting with the ß-lactam moiety at different conditions. The probes also contain a biotin group for application in an immunoassay format. Three different amoxicillin adducts have been obtained, purified and characterized by HPLC-MS and NMR techniques. These results have helped us to elucidate and propose a new antigenic determinant for ß-lactams, named the "penamidyl" epitope. All the adducts have been validated and evaluated with sera from different penicillin allergic patients by means of a Magneto-ELISA, immunochemical technique that has allowed us to detect specific IgEs in a very high percentage of the serum samples. An immunoassay has been developed, validated and applied as a diagnostic tool for the detection of specific IgEs in the sera of penicillin allergic patients using a new antigenic determinant.

Impaired gamma interferon response to Mycobacterium vaccae antigens in patients with cavitary pulmonary tuberculosis.

The ability of tuberculosis patients to recognize Mycobacterium vaccae-specific antigens before starting chemotherapy and according to disease severity was analyzed. We report that the M. vaccae cell wall skeleton fraction triggers more enhanced cytokine production than the whole bacterium. Moreover, a tendency was observed for a lower gamma interferon/interleukin-10 ratio in patients with cavitary disease induced by M. vaccae antigens.

Mice with pulmonary tuberculosis treated with Mycobacterium vaccae develop strikingly enhanced recall gamma interferon responses to M. vaccae cell wall skeleton.

Whole heat-killed Mycobacterium vaccae is used as an immunotherapeutic agent in tuberculosis (TB), but the compound(s) that triggers its immunostimulatory ability is not known. Here, we show that among different subcellular fractions, the cell wall skeleton induced a prominent expression of gamma interferon in splenocytes from both non-TB and TB M. vaccae-treated mice.

The production of a new extracellular putative long-chain saturated polyester by smooth variants of Mycobacterium vaccae interferes with Th1-cytokine production.

Mycobacterium vaccae is of major pharmaceutical interest as an immunotherapeutic agent. Although M. vaccae 15483 ATCC(T) strain displays smooth and rough colonial morphologies on solid culture media, it is not known in which conditions M. vaccae switches from one colonial morphotype to the other or whether there are biological differences, especially immunological, between them. We have found that the change from a smooth to rough stable variant occurs spontaneously at 30 degrees C. The analysis of the composition of the cell wall in both variants showed that the smooth morphotype presents an extracellular material that has never previously been described and was identified as a long-chain saturated polyester that, interestingly, is not produced by the rough morphotype. Our results also indicate that this compound could be implicated in the spreading ability of smooth colonies. Proliferation, IFN-gamma and IL-12(p40) production by splenocyte cultures was significantly higher in mice immunised with the rough variant compared with those immunised with the smooth one. This latter finding suggests that the different colonial morphology of M. vaccae may affect the immunomodulatory effects induced from M. vaccae preparations.