Can Allergies Cause Strep Throat?

Did you know about 32 million people in the US suffer from allergies? Did you know that the American Academy of Allergy in its communication mentioned that 10.8% of allergies from food put approximately 26 million adults' lives in jeopardy? It is also the sixth leading cause of chronic illness in the US. Anaphylaxis is a life-threatening, acute allergic reaction to a foreign substance and is increasingly being seen in developing countries. Allergy is a hypersensitive reaction by the body's immunity trigger using antibodies like IgE or other defence mechanisms. 

There are many diseases that can be classified as allergies like rhinitis, conjunctivitis, eczema, food allergy, and asthma. Adults and children can be affected by allergy, and allergy and allergy-related symptoms are widespread among children and need careful monitoring by primary care physicians.^2,3 In addition to these clinical manifestations of allergies, sore throat is also being increasingly considered to be due to allergies. Studies report that sore throat can be caused by a resolute cough, post-nasal drainage from allergic rhinitis and conjunctivitis. Rapid tests and newer antibiotics have complicated diagnoses and a risk score model with presentations of symptoms is an effective way to treat strep throat.^4,5 

Allergies

An Austrian scientist–paediatrician Von Pirquet introduced the term ‘allergy’ in 1906 in allergy-mediated IgE or antibody reactions. There is a marked increase in allergic conditions worldwide, and the prevalence in countries like Sweden has doubled in a 12-year period. 

Allergies like rhinitis, eczema, and contact dermatitis are the most common chronic illness. Atopic diseases would mean IgE-mediated responses arise in genetically predisposed individuals to environmental insults and irritants like allergic asthma, contact dermatitis, and hypersensitivity pneumonitis in IgE-dependent and independent mechanisms. Common allergens include pet dander, mites, and dust. In general, adults and children develop Ig1 and Ig4 antibodies, and in vitro T-cells respond to specific allergens, while the allergic person has exaggerated responses seen by higher levels of IgE antibodies to specific allergens as well as common aeroallergens in a skin-prick test. They are also characterized by the presence of Th2 cells as opposed to Th1 cells. 

Some of the common and highly toxic allergy-inducing proteins are Derp1 and Derp2 from dust mites, Feld1 from the cat, Bet1 or Bet v1 from birch tree (tree allergens), grass allergens, short ragweed, latex, rubber, and peanut proteins. The causes of allergies are infections, smoking, non-steroidal anti-inflammatory drugs (NSAIDs), and some occupations.⁶ 

Common Allergies

Common allergies include pollen, dust mites, pet dander, hay fever (allergic rhinitis), cockroaches, medicines, mould spores, food allergies, and latex. In food allergy, the most common causes are peanuts, shellfish, eggs, cows milk, fruits, wheat, and tree nuts. Insect bites also cause allergies like honeybees, ants, hornets, wasps, and yellow jackets.

Symptoms

Some of the symptoms include wheezing, cough, red eyes, whistling in the chest due to phlegm and inflammation, cold, or flu. Some other nasal symptoms include congestion, sneezing, itching, and rhinorrhoea. According to the NHS, ocular symptoms include itchy, red, and watering eyes. Other symptoms include vomiting, diarrhoea, tummy pain, feeling sick, and dry, painful or cracked skin. 

Swelling of the throat and mouth, breathing problems, dizziness and confusion, pailing or bluish tint of skin and/or lips, collapsing down, and consciousness loss are the signs of anaphylaxis that one must be worried about.

How can allergies cause a sore throat?

Sore throat is caused by a direct infection of the pharyngeal tissue called pharyngitis. It can be caused by virus, bacteria like streptococcus, and other pathogens. Other non-pathogenic modes of strep throat manifestation include allergies like rhinitis or sinusitis. It has also been reported that susceptibility to streptococcus infections, warts, and HIV are linked to allergic conditions like atopic dermatitis. Skin forms the first barrier against infections, and a weakening of the defence underlies barrier disruption in AD and is correlated with getting strep throat. Thus, a person with weak immune systems also gets strep throat easily.^9,10 

Group A streptococcus (GAS) causes strep throat infections especially among school-going children. This infection is typically seen in winter and in early spring. Symptoms of strep throat include fever with temperatures greater than 100.4°C, headache, abdominal pain, nausea, and vomiting. Other symptoms are swollen glands in the neck, white patches filled with pus in the throat, and small red spots in the upper palate of the mouth. GAS is the most common cause of strep throat among other bacterial infections, and up to 30% of children will have a sore throat due to GAS. It is uncommon to see GAS in younger children under the age of three but sometimes symptoms like runny nose and congestion, low-grade fevers, and tendering of glands in the neck can be seen. 

What is the difference between a sore throat and strep throat?

A common problem for physicians is to differentiate between viral infections and bacterial infections that cause strep throat. There are tests that differentiate between strep throat is caused by Streptococcus bacteria. A sore throat could have additional reasons and only 10% are caused by streptococcal infections. Viral infections like the Epstein-Barr virus are higher causative agents in 85%-95% of adults and also the majority of sore throats in children. Usually, it affects children who present symptoms like fever, a throat exudate, absence of cough, and a runny nose. If only one of these symptoms exists it is unlikely that it's strep throat. According to Mayoclinic.com, pain or scratchy sensation in the throat, pain with swallowing and pain, and swollen red tonsils, while talking are symptoms of sore throat. Some causes of sore throat include allergies, viral infections that cause chicken pox and cold, dry air, injury and environmental irritants.

Treating strep throat

Antibiotics are given for strep throat as they protect against acute sinusitis, acute rheumatic fever, and acute otitis and patients become symptom-free within one week. The drug of choice is penicillin, which is recommended twice a day and for a 5-day course as it is more effective than a 10-day course. Additional medications include NSAIDs and non-antibiotic therapy. Over-the-counter drugs like Ibuprofen (Motrin IB) and Tylenol are good pain relievers.

Summary

There are a lot of differences between a sore throat caused by viral infections and bacterial infections. Bacterial strep throat can be caused by streptococcus infections and other reasons like seasonal allergies. This is because allergies affect people with weakened immunity and the same goes for strep throat infections. It could also be said that because of a weak skin barrier seen in people with allergies like atopic dermatitis it is easier to be susceptible to streptococcal infections. It is also caused by post-nasal drip from allergies. Treatment includes a course of antibiotics and pain relievers.