Q: I am a 61 years old male with a history of loss of weight of about 10 kg in a period of two and a half months. All tests conducted at tertiary centre at Delhi were negative except for borderline increase in iodine uptake (3.8) T3 and T4 were raised. Appetite is normal and except for tiredness on exertion there is no abnormality. My weight is about 58 kg (formerly 68kg). What further tests do I need to take up? What could be the reason for the weight loss (loss of weight was preceded by viral fever with episodes of vomiting)?

A:There are four causes of loss of weight with a good or normal appetite. * Intestinal worm infestation * Thyrotoxicosis (over activity of the thyroid gland) * Diabetes mellitus * Malabsorption Your symptoms and test results suggest that you may have an overactive thyroid gland. One test that is missing is the TSH level which will be suppressed if you have thyrotoxicosis. Apart from loss of weight in spite of a good appetite and food intake, the patient are also fidgety, irritable, intolerant of hot weather and have palpitations. The history of fever would also suggest that you might have had subacute thyroiditis with transient increase in T3 and T4 but in such a case the iodine uptake is flat. Your iodine uptake was raised which favours a diagnosis of thyroid overactivity. You will need to have your TSH checked. I would suggest a consultation with a physician, preferably an endocrinologist.