Cachexia (/kəˈkɛksiə/; from Greek κακός kakos "bad" and ἕξις hexis "condition") or wasting syndrome is loss of weight, muscle atrophy, fatigue, weakness, and significant loss of appetite in someone who is not actively trying to lose weight. The formal definition of cachexia is the loss of body mass that cannot be reversed nutritionally: Even if the affected patient eats more calories, lean body mass will be lost, indicating a primary pathology is in place.Cachexia is seen in patients with cancer, AIDS, chronic obstructive lung disease, multiple sclerosis, congestive heart failure, tuberculosis, familial amyloid polyneuropathy,gadolinium poisoning, mercury poisoning (acrodynia) and hormonal deficiency.It is a positive risk factor for death, meaning if the patient has cachexia, the chance of death from the underlying condition is increased dramatically. It can be a sign of various underlying disorders; when a patient presents with cachexia, a doctor will generally consider the possibility of cancer, metabolic acidosis (from decreased protein synthesis and increased protein catabolism), certain infectious diseases (e.g., tuberculosis, AIDS), chronic pancreatitis, and some autoimmune disorders, or addiction to amphetamine. Cachexia physically weakens patients to a state of immobility stemming from loss of appetite, asthenia, and anemia, and response to standard treatment is usually poor. Cachexia includes sarcopenia as a part of its pathology.