Scombroid syndrome is a food poisoning caused by instamine , which can occur by eating fish or fish products that contain high amounts of this element .
What is histamine
Histamine is a molecule found in some fish products as a result of the decomposition of histidine , an amino acid present in the muscle tissues of species belonging to the Scombridae and Scomberascidae families: tuna , mackerel , sardines , bonito , dolphin fish sardines , anchovies , herring and sometimes salmon .
This process is partly due to the passage of time which makes the fish less and less fresh but above all to the incorrect conservation of these foods which leads to the proliferation of bacteria which accelerate decomposition and consequently the formation of large quantities of histamine.
Histamine by itself would not be harmful to the body since it is already present in the human body and plays an important role in regulating the immune system . Intoxication occurs when this element is introduced from the outside, as in the case of eating spoiled fish . The body’s reaction to this event is not standard but if the histamine in the fish you eat reaches very high levels it could lead to serious food poisoning.
Scombroid syndrome symptoms
Most often scombroid syndrome occurs after about 20-30 minutes from the moment in which the contaminated food has been ingested . Symptoms are usually mild, short-lived, and resolve on their own. The most common are itching , headache , abdominal pain , diarrhea and palpitations , dry mouth , nausea and vomiting .
Furthermore, very often, those who develop it feel a metallic, bitter or spicy taste in the mouth and redness of the face which can also extend to the chest , albeit rarely.
Finally, in the most serious cases, breathing difficulties , heart problems, low blood pressure and loss of consciousness can occur .
Usually the symptoms fade over time and disappear within 6-8 hours, although the general malaise generated by histamine can also accompany for 24 hours.
How to tell if it’s scombroid syndrome
Scombroid syndrome was identified for the first time in 1799 in Great Britain but although it has been known for centuries, it is very often not recognized or underestimated because its manifestations are quite similar to those of a food allergy.
However, although it can happen to confuse them, there is a difference between allergy and scombroid syndrome. In food allergies , in fact, histamine is produced by the human body as a response to allergens, while in scombroid syndrome it is present in the food that is ingested, therefore it is introduced from the outside
Especially if you rely on self-diagnosis, however, understanding whether it is one or the other problem is not easy.
If in doubt, there are several factors to consider. First of all, developing new allergies in adulthood is an uncommon eventuality and if the reaction occurs after eating a fish that has been eaten habitually without problems, the probability that it is scombroid syndrome increases.
To be sure, however, it is necessary to analyze the offending food and measure the amount of histamine through specific tests that are carried out in the laboratory.
Although the reactivity varies from person to person, generally a concentration of histamine higher than 50 milligrams per 100 grams of fish can cause poisoning.
In addition to food allergies, however, there are other pathologies with manifestations similar to scombroid syndrome such as anikasis infestation, a worm also contained in fish, serious heart disease or some tumors such as carcinoid syndrome and pheochromocytoma .
How to cure scombroid syndrome
If the symptoms of scombroid syndrome are mild there is no need to worry . In this case taking antihistamines by mouth may be sufficient to control and resolve them. If, on the other hand, they are more intense, it is necessary to consult a doctor.
The concentration of histamine contained in poorly preserved fish which can cause this problem is not always the same and when it is much higher than what the human body is used to producing and managing, the manifestations can also be very serious.
Particular attention should be paid to elderly people who suffer from pre-existing respiratory or cardiovascular diseases or who take drugs that further slow down the degradation of histamine.
How to prevent the formation of histamine
Once formed, histamine is quite resistant and almost impossible to eradicate on contaminated food. Cooking, smoking, freezing or sealing foods that contain it therefore very often does not help to protect yourself from intoxication.
To prevent scombroid syndrome it is essential that the production chain works perfectly, as well as the conservation process, which also requires strict observation of the cold chain.
Several studies have shown that 2 or 3 hours at temperatures of 20°C or higher would be sufficient for fish to produce toxic amounts of histamine. To avoid dangers and prevent bacteria from proliferating, fish must be kept at temperatures of 0 °C or lower.
