In medicine, a symptom is any evidence or affliction which indicates the presence of illness or disease. In many cases, the evidence is subjective and can only be detected by the patient, such as in the case of nausea, weakness, or pain. Symptomatology is the science devoted to studying symptoms for the purpose of making a diagnosis. This term is also used to describe the combined symptoms of a particular disease.
Mental illness is a condition that can rarely be diagnosed with physical tests, but must rely on careful evaluation of health history, behavior, patient interviews, family observations, and psychological evaluations. Psychiatric symptomatology is measured by several screening tests which take into account the subjective responses of patients to determine mental health conditions and proscribe treatment plans. Some symptoms, when present for a sustained period of time, may indicate mental health problems. These include wide mood swings, confusion, sustained irritability, drastic changes in eating or sleeping, rages, or hallucinations.
Different mental health problems have their own unique symptomatology in the same ways as physical illnesses. Schizophrenia, for example, is diagnosed through positive and negative symptoms. Positive symptoms are those which occur because of the condition, such as hallucinations, delusions, extreme agitation, social withdrawal and disorganized thinking. Negative symptoms, or symptoms the patient has ceased to exhibit, include a loss of initiative, social withdrawal, unresponsiveness and apathy. This differs from depressive symptomatology, which includes prolonged sadness, a sense of guilt or worthlessness, exhaustion, hopelessness and a lack of interest in former activities.
Many physical diseases can be diagnosed through medical tests, yet physicians examine the symptomatology in order to isolate possible conditions and determine which tests should be administered. If a patient describes episodes of nervousness, trembling, sweating, weakness and lightheadedness between meals, he may suffer from hypoglycemia, a condition caused by low blood sugar. In contrast to this, if a patient has experienced unexplained weight loss, increased urination, constant thirst, fatigue and tingling in his hands and feet, he may be suffering from hyperglycemia, or diabetes, which is caused by too much sugar in the blood.
There are other physical conditions for which no definitive diagnostic tests exist. Some of these include chronic fatigue syndrome, fibromyalgia, and irritable bowel syndrome; diagnosis is made primarily upon symptomatology and the patient’s response to different treatments. In these cases, doctors generally conduct a battery of tests to eliminate the possibility of other physical conditions which may evidence in a similar manner.
Symptomatology also has forensic applications. One of the challenges faced in settling accident claims is to determine the truthfulness of the complaining party when describing his or her symptoms, and to make a valid assessment of damages. In a number of cases people have feigned more serious injury or impairment in an effort to receive a greater settlement, a situation which is referred to as malingering. Some individuals who are faced with prosecution have been found to feign symptoms indicating mental incapacitation in order to avoid or mitigate prosecution. Screening tools have been developed to identify malingered symptomatology, or feigned symptoms of a condition.