***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND The natural history of allergic sensitization is complex and poorly understood . A prospect i ve nonr and omized study was carried out in a population of asthmatic children younger than 6 years of age whose only allergic sensitivity was to house dust mites ( HDMs ) . OBJECTIVES The study was design ed to determine whether specific immunotherapy ( SIT ) with st and ardized allergen extracts could prevent the development of new sensitizations over a 3-year follow-up survey . METHODS We studied 22 children monosensitized to HDM who were receiving SIT with st and ardized allergen extracts and 22 other age-matched control subjects who were monosensitized to HDM .  The initial investigation included a full clinical history , skin tests with a panel of st and ardized allergens , and the measurement of allergen-specific IgE , depending on the results of skin tests . Children were followed up on an annual basis for 3 years , and the development of new sensitizations in each group was recorded . RESULTS Ten of 22 children monosensitized to HDM who were receiving SIT did not have new sensitivities compared with zero of 22 children in the control group ( p = 0.001 , chi square test ) . CONCLUSIONS This study suggests that SIT in children monosensitized to HDM alters the natural course of allergy in preventing the development of new sensitizations BACKGROUND Data on the long-term effects of sublingual immunotherapy ( SLIT ) are sparse , and the optimal duration of treatment is a matter of debate . OBJECTIVE We sought to prospect ively evaluate the long-term effect of SLIT given for 3 , 4 , or 5 years and to compare the effect of those different duration s. METHODS In this prospect i ve open controlled study we followed up patients with respiratory allergy who were monosensitized to mites for 15 years . The subjects were divided in 4 groups receiving drug therapy alone or SLIT for 3 , 4 , or 5 years . Clinical scores , skin sensitizations , methacholine reactivity , and nasal eosinophil counts were evaluated every year during the winter months . The clinical effect was considered to persist until clinical scores remained at less than 50 % of the baseline value , and then patients underwent another course of SLIT . RESULTS Seventy-eight patients were enrolled , and 59 completed the study . In the 12 control subjects no relevant change in clinical scores was seen throughout the study . In the patients receiving SLIT for 3 years , the clinical benefit persisted for 7 years . In those receiving immunotherapy for 4 or 5 years , the clinical benefit persisted for 8 years . New sensitizations occurred in all the control subjects over 15 years and in less than a quarter of the patients receiving SLIT ( 21 % , 12 % , and 11 % , respectively ) . The second course of vaccination induced a benefit more rapidly than the first course . The behavior of bronchial hyperreactivity and nasal eosinophils paralleled the clinical score . CONCLUSION Under the present conditions , it can be suggested that a 4-year duration of SLIT is the optimal choice because it induces a long-lasting clinical improvement similar to that seen with a 5-year course and greater than that of a 3-year vaccination BACKGROUND Previous studies have suggested that single-allergen-specific immunotherapy ( SIT ) may prevent sensitization to other airborne allergens in monosensitized children . We aim ed to assess the prevention of new sensitizations in monosensitized children treated with single-allergen SIT injections in comparison with monosensitized patients given appropriate pharmacologic treatment for their disease . METHODS A total of 147 children with rhinitis and /or asthma monosensitized to house dust mite were studied ; 45 patients underwent SIT with adsorbed extracts and 40 patients underwent SIT with aqueous extracts for 5 years . The control group was comprised of 62 patients given only pharmacologic treatment for at least 5 years . Skin prick tests , medication scores for rhinitis and asthma , and atopy scores according to skin prick tests were evaluated at the beginning and after 5 years of treatment . RESULTS All groups were comparable in terms of age , sex , and disease characteristics . At the end of 5 years , 64 out of 85 ( 75.3 % ) in the SIT group showed no new sensitization , compared to 29 out of 62 children ( 46.7 % ) in the control group ( P = .002 ) . There were no differences between the SIT subgroups with regard to onset of new sensitization ( P = .605 ) . The patients developing new sensitizations had higher atopy scores ( P = .002 ) and medication scores for both rhinitis ( P = .008 ) and asthma ( P = .013 ) in comparison to patients not developing new sensitizations after 5 years of SIT . CONCLUSION According to our data , SIT has the potential to prevent the onset of new sensitizations in children with rhinitis and /or asthma monosensitized to house dust mite BACKGROUND Sublingual immunotherapy ( SLIT ) has been proved to be effective in allergic rhinitis and asthma , but there are few data on its preventive effects , especially in children . OBJECTIVE To evaluate the clinical and preventive effects of SLIT in children by assessing onset of persistent asthma and new sensitizations , clinical symptoms , and bronchial hyperreactivity . METHODS A total of 216 children with allergic rhinitis , with or without intermittent asthma , were evaluated and then r and omized to receive drugs alone or drugs plus SLIT openly for 3 years . The clinical score was assessed yearly during allergen exposure . Pulmonary function testing , methacholine challenge , and skin prick testing were performed at the beginning and end of the study . RESULTS One hundred forty-four children received SLIT  and 72 received drugs only . Dropouts were 9.7 % in the SLIT group and 8.3 % in the controls . New sensitizations appeared in 34.8 % of controls and in 3.1 % of SLIT patients ( odds ratio , 16.85 ; 95 % confidence interval , 5.73 - 49.13 ) . Mild persistent asthma was less frequent in SLIT patients ( odds ratio , 0.04 ; 95 % confidence interval , 0.01 - 0.17 ) . There was a significant decrease in clinical scores in the SLIT group vs the control group since the first year . The number of children with a positive methacholine challenge result decreased significantly after 3 years only in the SLIT group . Adherence was 80 % or higher in 73.8 % of patients . Only 1 patient reported systemic itching . CONCLUSIONS In everyday clinical practice , SLIT reduced the onset of new sensitizations and mild persistent asthma and decreased bronchial hyperreactivity in children with respiratory allergy BACKGROUND Grass pollen immunotherapy for allergic rhinitis is a disease-modifying treatment that results in long-term clinical tolerance lasting years after treatment discontinuation . Active treatment is associated with generation of inhibitory grass pollen-specific IgG antibodies capable of blocking allergen-IgE interactions . OBJECTIVES We sought to investigate the involvement of IgG-associated inhibitory antibodies with long-term clinical tolerance after discontinuation of grass pollen immunotherapy . METHODS We conducted a 4-year study in which patients who had moderate-to-severe allergic rhinitis underwent a r and omized , double-blind ,  placebo-controlled discontinuation of subcutaneous grass pollen immunotherapy .  All subjects received grass pollen immunotherapy injections for 2 years ( n = 13 ) , followed by a further 2 years of either active ( n = 7 ) or placebo ( n = 6 ) injections . Clinical outcomes included seasonal symptoms and use of rescue medication . Serum specimens were collected at baseline and after 2 and 4 years for quantification of allergen-specific IgG antibodies . Sera were also tested for IgG-dependent inhibitory bioactivity against IgE-allergen binding in cellular assays by using flow cytometry and confocal microscopy to detect binding of IgE-grass pollen allergen complexes to B cells . RESULTS Clinical improvement was maintained after 2 years of discontinuation . Although immunotherapy-induced grass pollen-specific IgG1 and IgG4 levels decreased to near-preimmunotherapy levels during discontinuation , inhibitory bioactivity of allergen-specific IgG antibodies was maintained unchanged . CONCLUSION Grass pollen immunotherapy induces a sub population of allergen-specific IgG antibodies with potent inhibitory activity against IgE that persists after treatment discontinuation and that could account for long-term clinical tolerance BACKGROUND We wondered whether short-term coseasonal sublingual immunotherapy ( SLIT ) can reduce the development of  asthma in children with hay fever in an open r and omized study . OBJECTIVE We sought to determine whether SLIT is as effective as subcutaneous immunotherapy in reducing hay fever symptoms and the development of asthma in children with hay fever . METHODS One hundred thirteen children aged 5 to 14 years ( mean age , 7.7 years ) with hay fever limited to grass pollen and no other clinical ly important allergies were r and omized in an open study involving 6 Italian pediatric allergy centers to receive specific SLIT for 3 years or st and ard symptomatic therapy . All of the subjects had hay fever symptoms , but at the time of study entry , none reported seasonal asthma with more than 3 episodes per season . Symptomatic treatment was limited to cetirizine , loratadine , nasal budesonide , and salbutamol on dem and . The hay fever and asthma symptoms were quantified clinical ly . RESULTS The actively treated children used less medication in the second and third years of therapy , and their symptom scores tended to be lower . From the second year of immunotherapy , subjective evaluation of overall allergy symptoms was favorable in the actively treated children . Development of asthma after 3 years was 3.8 times more frequent ( 95 % confidence limits , 1.5 - 10.0 ) in the control subjects . CONCLUSIONS Three years of coseasonal SLIT improves seasonal allergic rhinitis symptoms and reduces the development of seasonal asthma  in children with hay fever Background : Subcutaneous immunotherapy for respiratory allergy has shown a long lasting efficacy after its discontinuation , whereas evidence in the case of sublingual immunotherapy ( SLIT ) is weak . This retrospective study evaluates whether SLIT exerts a long-lasting effect and whether it relates to its duration . Methods : Sixty-five patients allergic to mite and positive to methacholine challenge 13 years ago were studied . Twelve ( control group , SLIT 0 ) were treated for 4 years only with st and ard pharmacological therapy ( SPT ) , while 53 received SLIT and SPT . Among these , four groups were identified according to SLIT duration . Fifteen patients were treated for 1 year ( SLIT 1 ) , 10 for 2 ( SLIT 2 ) , 14 for 3 ( SLIT 3 ) and 14 for 4 years ( SLIT 4 ) . Clinical parameters ( symptom monthly score , SMS ) , bronchial reactivity and FEV1 were evaluated in 1992 ( run-in ) , 1993 ( baseline ) and every 2 years from 1997 to 2005 . Results : Two to 3 years after the treatment ended , a positive effect on SMS , but not methacholine challenge and FEV1 , was seen in the SLIT groups versus SLIT 0 . At this time interval an effect on methacholine challenge was also seen in SLIT 3 . After 7–8 years a significant difference was seen for SMS , i.e. , it was significantly better in SLIT 4 than in the other groups , while bronchial reactivity was still improved in SLIT 1 , 3 and 4 only after 5–6 years . Conclusions : The effects of a 4-year SLIT on clinical parameters but not bronchial reactivity and FEV1 last 7–8 years after its discontinuation . SLIT shorter than 4 years yields proportionally less impressive results Sustained efficacy over three pollen seasons of pre‐ and co‐seasonal treatment with 300IR 5‐grass pollen sublingual tablet has been demonstrated in adults with moderate‐severe grass pollen‐associated allergic rhinoconjunctivitis OBJECTIVE To investigate the health and monetary consequences of treating allergy with specific immunotherapy ( SIT ) compared with symptomatic treatment/st and ard care among patients with grass pollen or mite allergy . METHODS We performed an economic analysis based on 253 grass- and /or mite allergic patients who started SIT from 1.1.1996 to 1.1.2002 at the Allergy Unit , Aarhus University Hospital and at a specialist practice in Aarhus . Relevant data were collected before , during and after SIT treatment from the national health service based on each patient 's personal identification number and medical records and from a specifically design ed question naire . A cost-benefit analysis including direct and indirect costs before , during and after SIT was performed . In addition direct costs were related to the clinical effect ( improvement in well-being ) in the form of a cost-effectiveness analysis . RESULTS The direct cost per patient/year before SIT ( equivalent to st and ard care ) was DKK 2,580 . The investment in SIT was DKK 27,545 ( in present values ) per patient over a 4-year period . After SIT the cost was reduced to DKK 1,072 per patient/year . In the long term , prospect i ve introduction of SIT incurred additional present-value 
    Output:
    
All but one study compellingly demonstrate cost savings conferred by AIT over SDT