Allergic diseases in the elderly: biological characteristics and main immunological and non-immunological mechanisms.

Life expectancy and the number of elderly people are progressively increasing around the world. Together with other pathologies, allergic diseases also show an increasing incidence in geriatric age. This is partly due to the growing emphasis on a more accurate and careful diagnosis of the molecular mechanisms that do not allow to ignore the real pathogenesis of many symptoms until now unknown, and partly to the fact that the allergic people from 20 years ago represent the elderly population now. Moreover, environmental pollution predisposes to the onset of allergic asthma and dermatitis which are the result of internal pathologies more than the expression of allergic manifestations. At the same time the food contamination permits the onset of allergic diseases related to food allergy. In this review we provide the state of the art on the physiological changes in the elderly responsible for allergic diseases, their biological characteristics and the major immunological and extra immunological mechanisms. Much emphasis is given to the management of several diseases in the elderly, including anaphylactic reactions. Moreover, some new features are discussed, such as management of asthma with the support of physical activity and the use of the AIT as prevention of respiratory diseases and for the purpose of a real and long lasting benefit. The mechanisms of adverse reactions to drugs are also discussed, due to their frequency in this age, especially in polytherapy regimens. Study of the modifications of the immune system is also of great importance, as regards to the distribution of the lymphocytes and also the presence of a chronic inflammatory disease related to the production of cytokines, especially in prevision of all the possible therapies to be adopted to allow an active and healthy aging.

Clonal mast cell disorders in patients with severe Hymenoptera venom allergy and normal serum tryptase levels.

BACKGROUND: Systemic mastocytosis is a clonal mast cell (MC) disease that can lead to potentially fatal anaphylactic reactions caused by excessive MC mediator release. The prevalence of mastocytosis in patients with Hymenoptera venom allergy is high, and thus the disease should be suspected in patients with severe reactions caused by Hymenoptera stings and increased serum basal tryptase (SBT) levels. OBJECTIVE: We sought to evaluate the presence of clonal MC disorders in patients seen at our mastocytosis center with Hymenoptera sting-induced anaphylaxis, documented hypotension, absence of urticaria pigmentosa, and normal SBT levels. METHODS: Twenty-two patients with Hymenoptera sting-induced anaphylaxis, without skin lesions, and with tryptase levels of less than 11.4 ng/mL underwent bone marrow evaluation. Bone mineral density was assessed in those patients with ascertained mastocytosis. RESULTS: In 16 of 22 patients, a diagnosis of indolent mastocytosis could be established, and 1 patient had a monoclonal MC activation syndrome. Patients with mastocytosis had higher SBT levels (P = .03) but only rarely had angioedema/urticaria associated with hypotension (P = .004). CONCLUSIONS: The absence of urticaria or angioedema in severe reactions to Hymenoptera stings with hypotension might represent the most relevant factor in identifying patients with mastocytosis, regardless of their serum tryptase levels.

Efficacy of venom immunotherapy given every 3 or 4 months: a prospective comparison with the conventional regimen.

BACKGROUND: Standard venom immunotherapy involves the administration of the maintenance dose every 4 to 6 weeks. This regimen may have adherence problems, especially in the long term; thus, extended intervals have been proposed. OBJECTIVE: We prospectively compared the efficacy of 3- or 4-month extended maintenance dose vs the conventional regimen. METHODS: Patients receiving immunotherapy with a single venom were offered the extended maintenance dose (EMD) and were then followed up for field re-stings. Only the re-stings by the insect for which the patients received immunotherapy were considered. A comparable group of patients receiving the conventional maintenance dose (CMD) was used for comparison by logistic regression analysis. RESULTS: Seventy-six patients (60 male; mean age, 48 years) receiving the EMD were re-stung on 247 occasions by the insect for which they were receiving immunotherapy. The group receiving CMD included 110 patients (82 male; mean age, 44 years) certainly re-stung on 167 occasions by the specific insect. The percentage of re-sting without reaction was 93.5% in the EMD group and 81.5% in the CMD group, with a significant difference in favor of the former (P=.001). At logistic regression analysis, only age, but not maintenance dose protocol, was predictive of subsequent systemic reactions. CONCLUSION: The EMD is as effective and safe as the CMD. An increased maintenance seems to be the best option in term of convenience and economic savings.

Efficacy and safety of honeybee and wasp tyrosine-adsorbed venom immunotherapy.

INTRODUCTION: It is acknowledged that any claim of efficacy of allergen immunotherapy must be done for each specific product, and this remains true also for venom immunotherapy (VIT). Thus, we evaluated the efficacy and safety of a specific tyrosine-adsorbed VIT for vespula spp. and honeybee in real-life. METHODS: Consecutive patients diagnosed with hymenoptera allergy, and receiving VIT for either vespula or honeybee with a tyrosine-adsorbed preparation were observed to evaluate the grade of reaction (according to Muller) at the first field re-sting. A modified ultra-rush protocol was used. RESULTS: A total of 247 patients (73 female) were observed (102 honeybee, group H, 145 vespula, group V). Seventy-five patients in group H had a re-sting, and 74/75 had a lower grade reaction at re-sting as compared to the pre-VIT reaction. Considering systemic reactions, protection was achieved in 89% of patients. In group V 118 patients were re-stung, and 76/118 patients with previous grade III-IV reaction had no more systemic reaction under VIT. Overall, considering systemic reactions, protection was achieved in 92% of subjects. Of note, in both groups there was a clear inverse correlation between the severity of pre-VIT and during VIT reactions. The duration of VIT at the time of re-sting did not affect the efficacy. The safety was overall good, with 18% ad 15.4% local reactions in groups H and V, respectively. DISCUSSION: Modified extracts, including tyrosine-absorbed, have the aim of improving the safety of VIT still yet maintaining the efficacy. Field re-sting is the best way to assess the efficacy in real life. In this observational study we could confirm the protective efficacy of the tyrosine-adsorbed extract, with a good safety expecially in the build-up using a modified-rush protocol. CONCLUSION: The tyrosine-adsorbed VIT used herein is a viable and advantageous form of treatment for hymenoptera allergy.

Immunity against infectious diseases: predictive value of self-reported history of vaccination and disease.

OBJECTIVE: To determine whether self-reported history of disease and/or vaccination is predictive of immunity against hepatitis B, varicella, rubella, mumps, and measles. DESIGN: The seroprevalence of viral antibodies and the predictive value of a self-report questionnaire were determined for 616 paramedical students who matriculated into Padua Medical School (Padua, Italy) during 2003-2005. RESULTS: The majority of subjects (86.9%) remembered being vaccinated against hepatitis B but had no recollection of disease. Among vaccinees, 1.5% showed markers of previous infection, 6.7% tested negative for anti-hepatitis B virus surface antigen (anti-HBsAg) antibodies, and 91.8% tested positive for anti-HBsAg. Self-reported vaccination history had a positive predictive value of 93.2% for test results positive for immunity against hepatitis B. Immunity against varicella (93.7% of subjects) and rubella (95.5%) was high, compared with immunity against mumps (79.9%) and measles (83.1%). In addition, results of tests for detection of immunity against mumps and measles were equivocal for more than 7% of subjects, probably because their vaccination regimen was not completed. Self-reported histories of varicella disease and rubella disease and vaccination had high positive predictive values (greater than 98% each) for testing positive for antiviral antibodies, compared with self-reported histories of mumps disease and vaccination and measles disease and vaccination; however, high positive predictive values were observed for self-reported histories of mumps only (92.0%) and measles only (94.7%). CONCLUSIONS: The self-report questionnaire used in this study did not accurately predict immunity against 5 transmittable but vaccine-preventable diseases. A complete serological evaluation of healthcare workers, followed by vaccination of those with negative or equivocal results of serological tests, is an appropriate measure to decrease the risk of infection in this population.

Recanalization rate in patients with proximal vein thrombosis treated with the direct oral anticoagulants.

BACKGROUND: The recanalization rate in patients with deep venous thrombosis (DVT) of the legs treated with the direct oral anticoagulants (DOAC) is unknown. METHODS: In an Italian cohort, we investigated the rate of residual vein thrombosis (RVT) after three and/or six months in 352 patients with proximal DVT who had been treated with the DOACs as a stand-alone therapy or lead-in parenteral anticoagulants, and compared it to that recorded in a historical cohort of 1094 patients in which vitamin K antagonists (VKAs) had been employed. In both cohorts, RVT was defined as the ultrasound persistence of thrombotic material resulting in a diameter of at least 4mm of incompressibility of the proximal veins. RESULTS: RVT was detected in 143 patients treated with DOACs (41.2%) after three months and in 58 patients (21.1%) after six months; the corresponding figure in patients treated with conventional anticoagulation was 52.3% and 54.5%, respectively. After adjusting for the baseline characteristics, the odds ratio of RVT in patients treated with the DOACs as compared with those treated with conventional anticoagulation was 0.63 (95% CI, 0.48-0.81) after three months, and 0.17 (95% CI; 0.11-0.26) after six months. CONCLUSIONS: In patients with proximal DVT treated with the DOACs, the persistence of ultrasound detectable RVT is likely to occur less frequently than in patients treated with conventional anticoagulation. These results may have implications for the prognosis of patients with DVT.