What are Crustaceans
They are crustaceans: prawns and shrimps, prawns, scampi, crabs, lobsters, cicadas, lobsters, squills, crabs, spider crabs, crabs, moeche of all kinds, etc.
Shellfish are considered valuable and very tasty foods; despite having a high cost, thanks to their palatability, they are among the most marketed fish foods in the world.
From a nutritional point of view, crustaceans are listed in the first fundamental food group. They have a moderate energy supply, contain high biological value proteins, B vitamins and mineral macroelements (calcium, phosphorus, sodium, etc.). They are also rich in astaxanthin (antioxidant provitamin A), cholesterol, essential omega 3 fats (eicosapentaenoic acid and docosahexaenoic acid) and important mineral microelements such as iodine, zinc and selenium.
Although nutritious, crustaceans have a very high allergic power ; that is why, like molluscs, they should be excluded from the children's diet and replaced with hypoallergenic fish such as cod.
What is shellfish allergy?
An allergy is an immunomediated adverse reaction (release of certain immunoglobulins) against one or more well-defined peptide sequences. In the case of food allergies, the symptoms (more or less serious) appear after the ingestion of the foods that contain these amino acid sequences; depending on the case, these symptoms can occur almost immediately or after many hours (following the digestion of the food to which you are allergic).
Shellfish is one of the most common, frequent and widespread allergies in the world. It is also one of the most dangerous and holds the absolute primacy of hospital admissions. It appears more often in adulthood than in the juvenile phase.
Shellfish allergy IS NOT synonymous with fish and shellfish allergy. Those who suffer from allergic reactions to molluscs can, in theory, safely eat "properly" fish (those with bones, for instance, such as sea bream, anchovies, tuna, etc.), cuttlefish, octopus, squid, squid, octopus, snails of sea and land, mussels, clams, cockles, cockles, oysters, scallops, scallops, sea truffles, razor clams, etc. On the other hand, before extending your food choices to these solutions, the shellfish allergy should consult an allergist and follow a very specific diagnostic procedure.
Note : although statistically the allergy to crustaceans is more often definitive, it is not known with certainty. This depends a lot on the case and no methods are known to identify the time of permanence.
Symptoms
What are the symptoms of shellfish allergy?
The most common symptoms of shellfish allergy are:
- He retched
- Stomach cramps
- Indigestion
- Diarrhea
- Urticaria spread throughout the body
- Breathing difficulty
- Wheezing breath
- Cough
- Hoarseness and swallowing problems
- Swollen tongue and / or lips
- bradycardia
- Pallor
- Dizziness and / or mental confusion.
Treatment
Management and treatment of shellfish allergy
Below we will briefly summarize the points necessary for the management and treatment of shellfish allergy:
- The first fundamental and inalienable rule of any allergy is to avoid the foods that trigger the symptomatic reaction; among these we remember:
- Crustaceans
- Foods that contain them or that contain their derivatives; Always check food labels carefully. It is advisable to pay close attention to products such as surimi, frying snacks, etc.
- Foods that have come into contact with you; it is essential, especially in meals consumed outside the home, to communicate effectively with the kitchen staff.
In the previous section we specified that shellfish allergy is a form of adverse reaction different from allergy to fish and molluscs. However, especially in collective catering, cases of cross-contamination caused by the mixture of the various products are not rare. To take a trivial example, if the "mixed fry" is offered on the restaurant menu, the various ingredients are probably mixed together. When ordering a "shrimp without shrimp", there is a high probability that the kitchen operator will simply remove the shrimp from the preparation. Or the same oil used for cooking could be rich in shrimp residues previously cooked. In both cases, a very sensitive allergic person would certainly encounter a more or less serious symptomatic reaction.
- ONLY for mild allergic forms, it is possible to keep certain symptoms at bay with the use of antihistamine and corticosteroid drugs
- Suspecting the onset of "potentially" serious allergic reactions, especially anaphylaxis (potentially fatal), it is essential to always have self-injectable epinephrine (adrenaline) medications on hand. It is also essential to make sure that these drugs:
- They are injected promptly when the first symptoms appear; remember that a severe allergic reaction is much more dangerous than the potential side effects of epinephrine (anxiety, restlessness, dizziness; rarely tachycardia, hypertension and pulmonary edema)
- They have not expired
- They are at least in two doses; the second one can be fundamental if the first one is broken or if the reaction is very serious.
- Furthermore, if the shellfish allergy is a child, in the absence of the parents, it is essential that the adults present at meals are informed and trained (eg school teachers, babysitters, etc.).
Note : It is important that the allergist provides a prescription that specifies the emergency treatment with the type of drugs to be used and the dosage, depending on the symptoms.
Diagnosis
Is shellfish allergy diagnosable?
For various reasons, the diagnosis of shellfish allergy can also be very complicated:
- If the allergy to shellfish is severe, the subject can reach the hospital without knowledge and, not being able to communicate with the health personnel, this slows down the diagnosis.
- Symptoms can be subjective and very different between people; let us not forget that allergic reactions to shellfish can affect the skin, the respiratory tract, the gastrointestinal tract and / or the cardiovascular system
- Symptoms may change from time to time, between episodes of the same person
- As we have said, in some cases the symptoms of allergy can appear even if only eating suitable foods, which however have come into contact with shellfish
- Not too frequently, there are cases of allergic reaction after inhaling the fumes / vapors of shellfish cooking.
When a food allergy is suspected it is important to consult an allergist, who can diagnose, prescribe specific tests and advise patients how to manage any symptoms of accidental ingestion.
The allergist's diagnostic process begins with a detailed investigation of the clinical history and symptoms of the hypothetical allergy to shellfish; for example, it will be necessary to report "what was eaten and in what quantity", "how long it took for the onset of symptoms", "what symptoms appeared" and "how long they lasted".
Afterwards, the allergist will prescribe a blood test (ImmunoCAP test) and / or perform a skin test himself, to verify the presence of food-specific immunoglobulin E (IgE).
Prick tests (skin-prik) are conducted on an outpatient basis and provide results within 15-30 minutes. They are performed by placing a drop of a liquid containing the allergen on the forearm or on the back of the patient and punching the skin with a small sterile probe (making the liquid penetrate). These tests, which are not particularly painful but rather annoying, are considered positive when the skin that comes into contact with the allergen turns red and swells (similar to an insect sting).
Blood tests are less sensitive than skin tests and measure the amount of IgE antibodies to specific allergenic foods. The results are generally available in one or two weeks and are reported with a numerical value to be contextualised in a specific range.
Remember that there are cases in which allergies are positive for the skin test but do not trigger symptoms with the food ingestion of the food in question. Furthermore, it should be specified that the amount of IgE measured by blood analysis is not necessarily proportional to the severity of the symptoms.
If both these diagnostic tools offer unclear results, for a definitive diagnosis, the allergist can choose to conduct a food test in which (under strict medical supervision) the patient is fed with increasing amounts of the potentially allergenic food.
