𝐂𝐡𝐢𝐜𝐤𝐞𝐧 𝐌𝐞𝐚𝐭 𝐀𝐥𝐥𝐞𝐫𝐠𝐲 and 𝐁𝐢𝐫𝐝 𝐄𝐠𝐠 𝐒𝐲𝐧𝐝𝐫𝐨𝐦𝐞
❓How many times have I been asked if children should avoid chicken if they are allergic to eggs?
❗Not as often as parents telling me their child is allergic to chicken meat or start sneezing when there is either cooked eggs or cooked chicken around.
⁉️Can this really happen?
✔Actually, it can, but we need to understand that 𝘢𝘭𝘭 𝘢𝘳𝘦 𝘳𝘦𝘭𝘢𝘵𝘪𝘷𝘦𝘭𝘺 𝘳𝘢𝘳𝘦.
Chicken Allergy can be primary or secondary; this one often called Bird Egg Syndrome.
✳But let us take this into the several aspects that might cause any of the above symptoms.
➡️The main difference between the two types is that the primary kind is associated with a protein called 𝘎𝘢𝘭 𝘥 𝟽 and the second called 𝘎𝘢𝘭 𝘥 𝟻.
What does it mean?
✴𝐆𝐚𝐥 𝐝 𝟕 is 𝘩𝘦𝘢𝘵 𝘴𝘵𝘢𝘣𝘭𝘦 (long term allergy), and 𝐆𝐚𝐥 𝐝 𝟓 is 𝘩𝘦𝘢𝘵 𝘥𝘦𝘨𝘳𝘢𝘥𝘢𝘣𝘭𝘦 (very likely to outgrow the egg or chicken meat allergy).
🔻The symptoms vary, according to age group:
▶️In adults, the signs are usually respiratory associated (asthma or wheeze) or affect the eyes or nose (rhinoconjunctivitis).
▶️In children, it will mainly affect the gastrointestinal tract or leading to breathing problems.
👫Children with egg allergy and respiratory symptoms related to bird egg syndrome, tend to either acquire tolerance later or not outgrow it.
𝘜𝘴𝘶𝘢𝘭𝘭𝘺, 𝘴𝘺𝘮𝘱𝘵𝘰𝘮𝘴 𝘴𝘵𝘢𝘳𝘵 𝘭𝘢𝘵𝘦𝘳 𝘪𝘯 𝘵𝘩𝘦𝘪𝘳 𝘭𝘪𝘷𝘦𝘴.
⛔As with egg allergy, be aware of the cross-reactivity between chicken meat and turkey meat.
🚫But there can also be reactions to duck or goose meat, 𝘵𝘩𝘰𝘶𝘨𝘩 𝘵𝘩𝘦 𝘳𝘦𝘢𝘤𝘵𝘪𝘰𝘯𝘴 𝘵𝘦𝘯𝘥 𝘵𝘰 𝘣𝘦 𝘮𝘪𝘭𝘥𝘦𝘳.
So you will need to avoid all those meats until a proper diagnosis is made.
❓One of the most common questions I get from mothers is "𝐢𝐬 𝐦𝐲 𝐜𝐡𝐢𝐥𝐝 𝐚𝐥𝐥𝐞𝐫𝐠𝐢𝐜 𝐭𝐨 𝐬𝐨𝐦𝐞𝐭𝐡𝐢𝐧𝐠 𝐈 𝐚𝐦 𝐞𝐚𝐭𝐢𝐧𝐠?".
🤱Many have decided to go on a food exclusion, without any 𝘗𝘢𝘦𝘥𝘪𝘢𝘵𝘳𝘪𝘤 𝘈𝘭𝘭𝘦𝘳𝘨𝘺 𝘋𝘪𝘦𝘵𝘦𝘵𝘪𝘢𝘯'𝘴 or 𝘗𝘢𝘦𝘥𝘪𝘢𝘵𝘳𝘪𝘤 𝘈𝘭𝘭𝘦𝘳𝘨𝘪𝘴𝘵'𝘴 advice, meaning potential nutritional deficiencies and substantial confusion to what is the causative agent, if any.
⚠️Fortunately, when there is a relationship between maternal food ingestion and an allergic reaction in a baby, they tend to be non-IgE mediated.
➡️Excellent information on the management of those reactions can be seen in an 𝐄𝐀𝐀𝐂𝐈 𝐏𝐨𝐬𝐢𝐭𝐢𝐨𝐧 𝐏𝐚𝐩𝐞𝐫: "Diagnosis and management of Non‐IgE gastrointestinal allergies in breastfed infants — An EAACI Position Paper.
👨⚕️For all the others, referral to a 𝘗𝘢𝘦𝘥𝘪𝘢𝘵𝘳𝘪𝘤 𝘈𝘭𝘭𝘦𝘳𝘨𝘪𝘴𝘵 should be considered, so investigations (mainly skin prick tests - SPTs) can be done.
▶️After that, coordination with a 𝘗𝘢𝘦𝘥𝘪𝘢𝘵𝘳𝘪𝘤 𝘈𝘭𝘭𝘦𝘳𝘨𝘺 𝘋𝘪𝘦𝘵𝘪𝘵𝘪𝘢𝘯 will lead to re-introduction of foods into the maternal diet and, eventually, into the child's diet as well.
▶️The dietitian will also advise on the need for supplementation if the diet is not adequate.
✅Before that appointment happens, it is always a good idea for mothers to keep a food and symptoms diary.
‼That often, on its own, can be enough for us to make a diagnosis and management plan.
⚠️Please do bear in mind that though only four main allergens have been investigated so far, it is highly likely all or most others will also be expressed in breast milk.
🔀Unfortunately, there is significant variability of allergen presentation in breast milk, which is often related to the method used to detect the proteins associated with those allergens.
👨💻Further research into a unified and conclusive investigative tool is of great importance, so clarifying and establishing a causal relationship between allergen ingestion on a mother and allergic reaction on a baby can be achieved.
⚠️Bottom line if worried about a potential allergic reaction in your breastfed child:
1️⃣Start a food and symptoms diary.
2️⃣Speak to your GP.
3️⃣Potential referral to a Paediatric Allergy Dietitian and/or Paediatric Allergist.
4️⃣Do not start a food exclusion on your own, especially extensive food exclusions.
It is an Allergy or an Intolerance?
🥛In a milk allergy, the body reacts to milk proteins, not milk sugar.
❗In lactose intolerance, there is little to no lactase (an enzyme produced by our body), so the milk sugar (lactose) cannot be digested.
⚠️Cow's milk protein allergy (CMPA) affects from 2 to 6% of children, with the highest prevalence during the first year of age.
➡️About 50% of children have been shown to resolve CMPA within the first year of age, 80-90% within their fifth year.
➡️Symptoms usually develop within a week of cow's milk introduction, although it may be delayed for many weeks, reported up to 24 and 36 weeks.
🔶️Lactose intolerance has 4 types:
1️⃣Primary (the most common form in which our bodies decrease the production of lactase from 5 years of age)
2️⃣Secondary (after a gut injury, illness or surgery our bodies produce less lactase)
3️⃣Developmental (mostly affecting preterms and resolving soon after birth)
4️⃣Congenital (rare and genetic in origin, where there is little to no lactase production - higher incidence in Finland)
💉The tests for both are different.
➡️skin prick tests or blood tests (specific IgE) for IgE mediated for milk allergy
➡️hydrogen breath test or stool sample for lactose intolerance
➡️no tests available for non-IgE mediated (normally food exclusion is the only option)
⚠️Obviously, the symptoms are also different.
➡️IgE mediated (immediate kind) affects the skin most commonly, then the gastrointestinal tract, and least frequently the respiratory system. Cardiovascular symptoms are rarely reported. Symptoms can range in severity from mild to life-threatening. Their onset is typically within minutes of exposure.
➡️Non-IgE-mediated (delayed kind) have typically an onset several hours and in some instances several days after ingestion. They tend to cause skin changes (eczema) and gastrointestinal disturbances (reflux with or without vomiting; constipation or diarrhoea).
➡️Lactose intolerance presents mainly with gastrointestinal problems (abdominal pain, flatulence and diarrhoea).
If you or your child have an immediate reaction to a food, avoid it and ask for a referral to either a Paediatric Allergist or an Adult Allergist.
In case the reactions are delayed (2 hours to several days), your best option is to be seen by either a Paediatric Dietitian or an Adult Dietitian.
The incidence of peanut allergy has been increasing significantly in developed countries.
Many reasons have been found for such growth, but so far no proper treatment has been found to deal with it.
Often, antihistamines are the first choice when there is an allergic reaction, with the occasional need to use adrenaline as well.
Most of the symptoms start in childhood and persists throughout life.
Due to this, the search for ways to deal with this specific allergy is ongoing, though not matching current needs.
As such, today, I will focus on a promising medication that might lead to a significant change in the way we deal with peanut, and possibly nut, allergy.
⚠️On a Phase 2a randomized placebo control trial, running for six weeks, a single injection of Etokimab showed that it could desensitize peanut allergic adults.
➡️Food challenges, skin prick tests and blood tests were done at day 15 and 45, after injection
➡️73% (first challenge) and 57% (second challenge) passed a food challenge with 275mg of peanut protein (versus 0% in the control group)
➡️Several immune mediators were also reduced
❗They concluded that it could potentially desensitize peanut-allergic participants and possibly reduce atopy-related adverse events.
❓I understand the first part, but what is the connection to atopy?
Let me explain.
🔸️IL33 belongs to a group of proteins (cytokines) important in cell signalling (basically part of the immune cascade).
🔸️It also belongs to a small group called alarmins, which are biomolecules that can initiate and maintain a non-infectious inflammatory response (like in allergies).
🔸️It is also known to be released or elevated when there is skin damage, like in atopic dermatitis or eczema (independently of its origin).
▶️Can you see me coming again to the top priority of maintaining the skin barrier to prevent allergy?◀️
⚠️My opinion about it:
How does it compare to the current two available oral peanut immunotherapy?
CA002 (Cambridge) and AR101 (London)
🔹️Both use an “up-dosing” programme to achieve a specific tolerable dose (1600mg for the former and 600mg for the latter).
🔹️AR101 had limitations, like participants being selected based on sensitivity to a maximum of 100 mg of peanut protein.
🔹️This does not represent the entire population with peanut allergies, half of whom have reactions to doses >100 mg.
⚠️Michael R. Perkin, Consultant Paediatric Allergist PhD, wrote that the major concern regarding this immunotherapy is that 𝐚𝐥𝐥𝐞𝐫𝐠𝐞𝐧 𝐭𝐨𝐥𝐞𝐫𝐚𝐧𝐜𝐞 𝐭𝐡𝐚𝐭 𝐢𝐬 𝐢𝐧𝐝𝐮𝐜𝐞𝐝 𝐰𝐢𝐥𝐥 𝐛𝐞 𝐭𝐞𝐦𝐩𝐨𝐫𝐚𝐫𝐲, 𝐚𝐧𝐝 𝐥𝐨𝐬𝐭 𝐢𝐟 𝐫𝐞𝐠𝐮𝐥𝐚𝐫 𝐜𝐨𝐧𝐬𝐮𝐦𝐩𝐭𝐢𝐨𝐧 𝐜𝐞𝐚𝐬𝐞𝐬.
▶️Neither groups have attempted to establish the duration for which allergen tolerance is maintained in the absence of ongoing consumption, potentially lifelong, 𝐫𝐞𝐠𝐮𝐥𝐚𝐫 𝐜𝐨𝐧𝐬𝐮𝐦𝐩𝐭𝐢𝐨𝐧 𝐦𝐚𝐲 𝐛𝐞 𝐧𝐞𝐞𝐝𝐞𝐝 𝐭𝐨 𝐦𝐚𝐢𝐧𝐭𝐚𝐢𝐧 𝐚𝐥𝐥𝐞𝐫𝐠𝐞𝐧 𝐭𝐨𝐥𝐞𝐫𝐚𝐧𝐜𝐞.
𝐓𝐡𝐢𝐬 𝐦𝐞𝐚𝐧𝐬 𝐩𝐚𝐭𝐢𝐞𝐧𝐭𝐬 𝐰𝐨𝐮𝐥𝐝 𝐧𝐞𝐞𝐝 𝐭𝐨 𝐭𝐚𝐤𝐞 𝐭𝐡𝐞 𝐦𝐞𝐝𝐢𝐜𝐚𝐭𝐢𝐨𝐧 𝐨𝐧 𝐚 𝐝𝐚𝐢𝐥𝐲 𝐛𝐚𝐬𝐢𝐬 𝐨𝐫 𝐭𝐡𝐞𝐫𝐞 𝐰𝐢𝐥𝐥 𝐛𝐞 𝐫𝐞𝐯𝐞𝐫𝐬𝐚𝐥 𝐨𝐟 𝐬𝐲𝐦𝐩𝐭𝐨𝐦𝐬. 𝐀𝐧𝐝 𝐭𝐡𝐢𝐬 𝐰𝐚𝐬 𝐚𝐥𝐫𝐞𝐚𝐝𝐲 𝐩𝐫𝐨𝐯𝐞𝐧 𝐢𝐧 𝐚 𝐫𝐞𝐜𝐞𝐧𝐭 𝐬𝐭𝐮𝐝𝐲.
➡️To consider that AR101 will cost between $5000 to $10,000 for the first six months of use, and $300 to $400 per month after that.
Dr Costa is a Consultant Paediatrician and fellow of the Royal College of Paediatrics and Child Health.