Weight loss, emaciation

Weight loss (wasting) - a frequent sign of illness. Drastic weight loss is called exhaustion and cachexia (the latter term is often used to refer to extreme exhaustion). Moderate weight loss may not be the only symptom of the disease, but are normal, due to the constitutional aspect of the body, such as in patients with asthenic body type.

Reasons for weight loss
Restriction mealImpaired consciousnessTraumatic brain injury, stroke.
DysphagiaTumors, narrowing of the esophagus, larynx.
Decreased appetiteAnorexia nervosa, intoxication.
IndigestionViolation of digestion of proteins, fatsAtrophic gastritis, peptic ulcer, pancreatitis, hepatitis, liver cirrhosis
Malabsorption of nutrientsCeliac disease, enteritis, colitis.
Infringement of metabolism (metabolism)Prevalence of fracture processes (catabolism) of the synthesis processSerious injuries, burns, cancer, endocrine pathology, diseases of the connective tissue.

In what diseases occur weight loss:
- Acute and chronic infections and parasitic diseases (intestinal infection, tuberculosis, syphilis, malaria, amoebiasis, helminth infections, HIV infection) 
- Diseases of the digestive tract (esophageal stricture, scar pyloric stenosis, malabsorption syndrome, chronic enterocolitis , liver cirrhosis, chronic pancreatitis) 
- Eating disorders (bulimia nervosa, anorexia) 
- Cancer  
The basis of weight loss may be insufficient or inadequate diet, violation of digestion, increased decay in the body of protein, fat and carbohydrates, and increased energy consumption (due to exogenous and endogenous). Often these mechanisms are combined. In various diseases of the time of appearance, severity, and specific mechanisms of weight loss are significantly different.
Weight loss can lead to both external factors (restricting food intake, trauma, infection) and internal (metabolic disorders, digestion and absorption of nutrients in the body).
- Prolonged emotional stress (loss of appetite) 
In all malignant tumors in the body of patients with a tumor cell takes metabolites (glucose, lipids, vitamins), which leads to disruption of the biochemical processes going on exhaustion of internal resources and develops cachexia (wasting). It is characterized by severe weakness, reduced work capacity and the possibility of daily tasks, reduced or lack of appetite. Many cancer patients is cancer cachexia is the immediate cause of death.
Weight loss - as the leading symptom is characteristic of certain endocrine disorders (hyperthyroidism, hypopituitarism, diabetes mellitus type 1). Under these conditions is a violation of development of various hormones, which leads to a serious breakdown of the metabolic processes in the body.
Thyrotoxicosis - a syndrome which includes conditions caused by an increase of thyroid hormones in the blood. In the body, there is an increased decay processes of protein and glycogen, reduced their content in heart, liver and muscles. It is manifested by general weakness, tearfulness, mood instability. Worry about heart attacks, arrhythmias, sweating, hand tremors. An important symptom is weight loss when stored appetite. It occurs in diffuse toxic goiter, toxic adenoma, the initial stage of autoimmune thyroiditis.
Hypopituitarism - a syndrome that develops due to inadequate secretion of anterior pituitary hormones. It occurs when the pituitary tumors, infectious diseases (meningoentsifality). Manifested by progressive weight loss (up to 8 kg per month) with the development of wasting (cachexia), expressed general weakness, dry skin, apathy, decreased muscle tone, faintness.
Type 1 diabetes - a disease caused by an absolute lack of insulin resulting from the autoimmune destruction of the beta cells of the pancreas, which leads to disruption of all types of metabolism and carbohydrate metabolism primarily (there is an increase in blood glucose, and its isolation in the urine). The debut of the disease occurs in childhood and adolescence, and progresses rapidly. The most common symptoms of the disease - a thirst, frequent urination, dry and itchy skin, progressive weight loss despite increased appetite, abdominal pain.
Intoxication syndrome is typical for infectious diseases, tuberculosis, helminthiasis. The causative agent of the disease, penetrating into the human body produces toxins that have a damaging effect on cell structure, disrupt the immune regulation occurs disorder function of various organs and systems. It is manifested febrile or low grade fever, loss of appetite, weight loss, increased sweating, weakness. Significant weight loss is characteristic of the current long-term, chronic infections.
Tuberculosis - is an infectious disease caused by Mycobacterium tuberculosis and is characterized by the formation of specific granulomas in various organs and tissues. The most common form of TB - tuberculosis of the lungs, which in addition to intoxication syndrome is characterized by a dry cough or sputum, shortness of breath, chest pain associated with breathing, coughing up blood, pulmonary hemorrhage.
Helminthiasis - human parasitic diseases caused by various representatives of the lower worms - worms. They secrete toxic substances that cause intoxication and violate the processes of digestion.
For helminthisms characterized by a gradual progression of the disease, weakness, abdominal pain associated with food intake, weight loss while maintaining appetite, itching, allergic rashes, the type of urticaria.
A significant loss of body weight, up to cachexia, is not related to the peculiarities of power as a result of immune disorders, characteristic of connective tissue disease - systemic scleroderma and polyarteritis nodosa.
Systemic scleroderma manifests skin lesions of the face and hands in a "dense" edema, shortening and deformity of the fingers, pain and a feeling of stiffness in the muscles, visceral.
For polyarteritis nodosa is characterized by skin changes - marble limbs and trunk, intense pain in the calf muscles, increasing blood pressure.
Weight loss is typical of most diseases of the gastrointestinal tract. Acute or chronic inflammation leads to a change in metabolism towards catabolism (destruction), increases the body's need for energy absorption and broken processes digestion. To reduce the pain in the abdomen, patients themselves often restrict food intake. A dyspeptic symptoms (nausea, vomiting, diarrhea) lead to loss of protein, minerals, electrolytes, which leads to disruption of the delivery of nutrients to the tissues.
Malnutrition - a disease that occurs due to prolonged malnutrition and starvation in the absence of organic disease that could be the cause of weight loss. It is characterized by progressive weight loss. There are two forms: cachectic (dry) and swelling. In the initial stages, it shows increased appetite, thirst, severe weakness. Is a violation of water-electrolyte metabolism, amenorrhea (absence of menstruation). Then, growing weakness, patients lose the ability to care for himself, and developed hungry (alimentary dystrophic) coma. The causes of the disease: social catastrophes (famine), mental illness, anorexia nervosa (refusal to take food out of a desire to lose weight).