A chronic cough can be due to lung cancer, but may also be related to allergies, recurrent viral infections, or a multitude of other conditions. Both COPD and lung cancer may have similar symptoms. Tuberculosis not only raises the risk of developing lung cancer, but the two are not uncommonly misdiagnosed as the other. Since there is so much overlap between different diagnoses, it's important to talk to your doctor about all of your symptoms, even if any of those symptoms seem mild. The combination of symptoms you experience may be more important than individual symptoms.
It is well known that almost all people with parathyroid disease will have obvious parathyroid symptoms, while some aren't quite so sure they have any. For this latter group (about 2-5%), it can only be known several months after the operation to remove the bad parathyroid gland. Almost all of those patients who thought they didn't have any parathyroid symptoms preoperatively will claim to sleep better at night, be less irritable, and find that they remember things much easier than they could when their calcium levels were high ( nervous system problems ). Just ask your family members if you have become more irritable or cranky over the past couple of years!
A sign has the potential to be objectively observed by someone other than the patient, whereas a symptom does not. There is a correlation between this difference and the difference between the medical history and the physical examination . Symptoms belong only to the history, whereas signs can often belong to both. Clinical signs such as rash and muscle tremors are objectively observable both by the patient and by anyone else. Some signs belong only to the physical examination, because it takes medical expertise to uncover them. (For example, laboratory signs such as hypocalcaemia or neutropenia require blood tests to find.) A sign observed by the patient last week but now gone (such as a resolved rash) was a sign, but it belongs to the medical history, not the physical examination, because the physician cannot independently verify it today.