Hello, First, have you had any symptom of flu recently - sneezing, coughing, hoarse voice, runny nose? - common cold or flu complicated with laryngitis might be the cause. You can take oral antibiotics, anti-histamines and oral spray or lozenges to relieve the edema caused by inflammation. You can consult an ENT specialist to check for other problems. Next, if the symptoms are not relieved with these first steps, you can do a fibro-gastro-scopy to check if there is any problem (strictures) of eosophagus. You can also do an ultrasound to check for any abdominal problems together with fecal examination. However, check for the signs of a flu or virosis or common cold first, then, go for the last examinations I mentioned. Hope it helped!