Allergy is an abnormal reaction to a particle which enters the body from the environment either by inhalation ( breathing), ingestion( eating), injection – (by bites of insects or by injection) and or by contact - the substance comes in contact on the surface of the skin or the mucous membrane of the body of person with allergy, which is usually harmless to other persons. whenever such substance enter the body, body recognizes the sensitive substance and a series of reactions happen either with in few seconds or in minutes to develop the various allergic manifestations
The common allergic diseases are :
The term allergic march or atopic march refers to progression or development of various allergic conditions with age. the tendency to have an allergic condition known as atopy makes one prone to develop other allergic conditions.
It is also noted that after certain age the allergy dissolves and becomes normal and recur after few years, which is commonly seen in most of the atopic children
Doctors and scientists are continually doing research for better understanding of allergy march.
in case, patient is experiencing any of the above symptom/symptoms, the patient is advised to take emergeny medical help prefferably in an emergency room of a hospital itself at the earlest
The causes of allergy are genetic predisposition, environment triggers and life styles. the genetic background plays a major role. It is commonly accepted that a if both parents are allergic the risk of developing allergy can be as high as 90%, if the father is allergic(but not the mother) the risk is upto 40%, where as if the mother is allergic(not father) the risk is upto 50% please also note that if parents are not at all allergic then also there is a 20% chance for getting allergy
Tenvironmental triggers play an important role. exposure to some type of pollens, fungus, dusts, insects, pets, some foods can trigger an allergy attack The exact life style for the cause of increasing allergic diseases is yet not identified, but most researchers agree that a close relationship with “westernisation of lifestyle”, one that results in a decreased bacterial load(eg. altered commensal flora) in young children may be one of the factors summarized as hygiene hypothesis
Our airway has multiple number ofmucous glands, which secrete mucus. This acts as a cleaning agent and traps dirt and other matter, which get wiped away by the beating movement of tiny hair like structures called the cilia. It is a natural process which occurs in the body to clean the airway by eliminating dirt and particulate matter(mucociliary escalator) these delicate tissues line the entire nasal cavity and the lung passages. Uncontolled allergic diseases over the years, can damage this natural mechanism , when the cilia and the mucus blanket are damaged, the mucociliary escalator is impaired the lung and sinuses, which cannot clean themselves, become clogged with thick diseased material and do not function normally.
Recurrent allergic symptoms may cause airway remodelling(smooth muscle hypertrophy, collagen deposition,hypertrophy of mucous glands,infiltration of inflammatory cells), which inturn decrease the internal diameter of the airways leading to more severe allergy symptoms as time progresses.
Skin prick test (spt) for common inhalant and food allergens is currently the best sensitive and reproducible test available at affordable cost. First performed by Dr.Charles blackley in 1865 to identify grass pollen sensitivity in hay fever. This test is an invivo test which is more specific than blood tests
Skin prick test is an extremely safe test in expert hands. The test is not at all painful and can be done very safely in childrens also.
Serum total ige have limited values as it can be elevated in non allergic conditions also.(like parasitic infestations,sle, rheumatoid arthritis,psoriasis,churg strauss syndrome, poly arteritis nodosa etc)
Estimating specific serum ige may be helpful, but is more costly(almost more than 10 times) and less specific than a skin test.
Corticosteroids are present in our own body in significant amounts, and help maintain many important functions of the body. If corticosteroids are taken orally for a long time, this can derange the body’s own production of steroids, and can cause problems. These problems are of course, reversible to a large extent. However, in allergy, inhaled steroids are used. These work directly on the air passage (target therapy).The dose is almost 1/1000 that present in a tablet. Since the inhaled steroids are used in such low doses that they do not get into the blood stream, they usually do not cause any side effects but wrong inhaler techniques and oral deposition can create problems.
Followup with the treating allergy specialist in regular intervals , while using the inhaled drugs is very essential.
Almost all adverse effects of steroids can develop including:
Diabetes mellitus, Hypertension, Osteoporosis, Immunosuppression, Striae on skin, Cushings habitus, Peptic ulcers, Delayed wound healing, recurrent infections, cataract, Raised pressure inside the eyeball, HPA axis suppression, Steroid induced psychosis etc..