What is the cause of dry cough and dust allergy?

Q: I am a 35 years old married woman, allergic to dust and specific vegetables like brinjal. Whenever I have an allergic problem, I take a tablet of Cetirizine and get relief. Nine months back, I had an operation for piles under general anaesthesia. After few days from recovery, I developed a chronic dry cough with instant irritation in the throat, which subsides for a while (maximum 6 hours) after taking Cetirizine, but starts again. Therefore, I continued to take Cetirizine on and off. After 4-5 months of above mentioned operation, I consulted three different ENT specialists for the same problem. They prescribed a few medicines including Topcef 200 mg twice daily dose for 14 days, Laveta-D twice daily for 14 days, Syrup Ventisol 2.5 tsp thrice daily, Tab Rupin twice daily for 10 days, etc. During this course, I got little relief, but the problem reappeared again when I stopped the treatment. Till now, none of the doctors advised me to do any investigation except an x-ray for PNS and found mild DNS (LF) with left maxillary sinusitis. Do I need any special type of investigation to confirm the diagnosis? Whom should I consult for treatment? What medicines should I take?

A:You had given a detailed description. You are an otherwise healthy lady, who used to have some food allergy in the past, and have developed a cough since nine months. The onset had coincided with a general anaesthetic. The cough refuses to go away. Your concern is quite understandable. As is usual with every other symptom in medicine, several conditions might result in persistent cough. What you need to do is to consult a General Physician. A personal consultation will help you to arrive at a correct diagnosis and to get relief. First, I will give you a general idea about the conditions leading to a persistent cough and then I will briefly describe how your doctor will go about this task.Cough is a protective reflex - it helps the body to eliminate any unwanted object in the throat, wind pipe and the lungs. Many times, dust may get into the airway and keep on irritating the mucosa and produce cough. Tuberculosis may cause persistent cough. Occasionally, asthma may masquerade as cough. Rarely, when you sleep on a full stomach, acid may reflux from the stomach and get into the lungs and produce irritation and cough. Such a cough will occur each time you lie down and may be associated with pain in the abdomen. Sometimes, due to heart failure, fluid may stagnate in the lower parts of the lungs and lead to cough. In this case, the cough will be manifest mostly in the nights and there could be associated swelling of feet. Another reason for such stagnation of fluid in the lungs could be kidney failure. In kidney failure, puffiness may occur around the eyes. Rarely, nothing might be wrong with any of the above organs and an abscess in the liver might irritate the diaphragm and cause coughing. Very rarely, a marked loss of weight and loss of appetite might occur. These features demand immediate attention, because they may presage some serious diseases.The task of identifying the cause of persistent cough is a very demanding one - but if you can confirm a diagnosis, it should provide great professional satisfaction to the doctor and even greater relief to you. First, your General physician will go over your complaints in finer detail. This is called 'history taking'. A carefully taken history will lead the physician in the proper direction. Then, he will proceed to examine you clinically. A knowledgeable examination will yield a great deal of information and will enable the physician to arrive at a set of probable diagnoses. This list of probable diagnoses is called 'the differential diagnosis'. A few simple laboratory tests will help him to reduce this list and to arrive at a definitive diagnosis. A common battery which will need to be done is Chest x-ray, Blood counts, ESR, Sputum examination for bacteria, ECG, Urinalysis, Blood sugar, Blood urea, Serum creatinine and Ultra sound examination of the abdomen. If the above algorithm does not lead to a diagnosis, certain advanced tests are also available e.g. Fibre optic bronchoscopy, CT scan, immunological tests etc.