Oralna i sublingvalna imunoterapija kod alergije na jaja
Abstract
Background
Clinical egg allergy is a common food allergy. Current management relies upon strict allergen avoidance. Oral immunotherapy (OIT) might be an optional treatment, through desensitization to egg allergen.
Objectives
We aimed to assess the successful desensitization and development of tolerance to egg protein and the safety of egg oral and sublingual immunotherapy in children and adults with immunoglobulin E (IgE)‐mediated egg allergy as compared to a placebo treatment or an avoidance strategy.
Search methods
We searched 13 databases for journal articles, conference proceedings, theses and unpublished trials using a combination of subject headings and text words (the last search was on 5 December 2013).
Selection criteria
Randomized controlled trials (RCTs) were included. All age groups with clinical egg allergy were to be included.
Data collection and analysis
We retrieved 83 studies from the electronic searches. We selected studies, extracted data and assessed the methodological quality. We attempted to contact the study investigators to obtain the unpublished data, wherever possible. We used the I² statistic to assess statistical heterogeneity. We estimated a pooled risk ratio (RR) with 95% confidence interval (CI) for each outcome using a Mantel‐Haenzel fixed‐effect model if statistical heterogeneity was low (I² value less than 50%).
Main results
We included four RCTs with a total of 167 recruited individuals (OIT 100; control 67 participants), all of whom were children (aged four to 15 years). One study used a placebo and three studies used an avoidance diet as the control. Each study used a different OIT protocol. Thirty nine per cent of OIT participants were able to tolerate a full serving of egg compared to 11.9% of the controls (RR 3.39, 95% CI 1.74 to 6.62). Forty per cent of OIT participants could ingest a partial serving of egg (1 g to 7.5 g; RR 5.73, 95% CI 3.13 to 10.50). Sixty nine per cent of the participants presented with mild‐to‐severe adverse effects (AEs) during OIT (RR 6.06, 95% CI 3.11 to 11.83). Five of the 100 participants receiving OIT required epinephrine. We cannot comment on whether over‐ or under‐reporting of AEs was a concern based on the available data. Overall there was inconsistent methodological rigour in the trials.
Authors' conclusions
The studies were small and the quality of evidence was low. Current evidence suggests that OIT can desensitize a large number of egg‐allergic patients, although it remains unknown whether long‐term tolerance develops. A major difficulty of OIT is the frequency of AEs, though these are usually mild and self‐limiting. The use of epinephrine while on OIT seems infrequent. There are no standardized protocols for OIT and guidelines would be required prior to incorporating desensitization into clinical practice.
PICO
Plain language summary
Liječenje alergije na jaja svakodnevnom primjenom malih, postupno sve većih količina proteina jaja
Jedina mogućnost za ljude koji imaju alergije na hranu do sada je uključivala strogo izbjegavanje hrane koja sadrži alergen. Jaja je teško izbjeći jer su ona čest sastojak hrane. Čak i strogim izbjegavanjem, i kod najpažljivijih pojedinaca prisutan je strah od slučajnog unosa alergena zbog pogrešno deklariranog sastava ili kontaminacije hrane. Slučajan unos hrane koja sadrži jaja može dovesti do situacija opasnih po život. Iako o tome nema mnogo objavljenih studija, opisana je nova terapija za alergiju na jaja zvana "oralna imunoterapija" (još zvana "oralna desenzitizacija" ili "cijepljenje"). Ona se sastoji od svakodnevnog uzimanja male količine proteina jaja, koja se postupno s vremenom povećava dok ne dođe do količine prisutne u jednom obroku. Tom terapijom moglo bi se utjecati na alergijski odgovor imunološkog sustava prema tim proteinima, tako da se poveća količina jaja koja se može pojesti bez poticanja neželjene reakcije.
Cochrane sustavnim pregledom pronađene su 4 randomizirane kontrolirane studije koje su kod ljudi s alergijom uspoređivale oralnu imunoterapiju s obzirom na placebo ili prehranu bez jaja. U tim je studijama ukupno sudjelovalo 167 djece u dobi od 4 do 15 godina, a od toga 100 u grupi koja je primala oralnu imunoterapiju te 67 u kontrolnoj grupi. Dokazi za sada pokazuju da bi oralna imunoterapija kod alergije na jaja mogla pomoći većini alergične djece da podnesu djelomičnu porciju jaja, uz svakodnevno uzimanje malih količina proteina jaja. Nuspojave su bile česte za vrijeme trajanja terapije, ali obično su bile blage do umjerene. Ipak, pet od 100 pacijenata liječenih oralnom imunoterapijom zahtijevalo je primjenu adrenalina zbog ozbiljne reakcije preosjetljivosti. Na koncu valja naglasiti da su pronađene studije uključile premalen broju ispitanika i postoje metodološki problemi s načinom kako su provedene, stoga su potrebna daljnja ispitivanja.
