Ricin poisoning is an acute condition that is caused by the toxic effect of the ricin protein on the body. Pathology occurs when the seeds of the plant are consumed, or when the poison enters the lungs by inhalation. The victim has severe abdominal pain, dyspeptic disorders, convulsive syndrome and impaired consciousness. The symptoms are supplemented by general intoxication signs. For the diagnosis of ricin poisoning, it is important to collect anamnesis, blood test, methods of instrumental visualization. Treatment includes the elimination of the toxin from the body (if possible) and the appointment of a complex of pathogenetic drugs.
X44 Accidental poisoning and exposure to other and unspecified drugs, medications and biological substances
The protein consists of two chains of peptides that are interconnected by a disulfide bond. Toxic properties are manifested in the form of inhibition of protein synthesis and agglutination of cells. The lethal dose for oral consumption is about 0.03 mg / kg of body weight. 20 seeds contain an average of 1 mg of poison.
In its pure form, ricin is an odorless white powder that is easily sprayed in the air, forming an aerosol, and dissolves well in water. It persists for a long time at low temperatures, but with prolonged storage in the form of an aqueous solution, it gradually loses its toxic properties.
Ricin can enter the body through the mucous membranes of the gastrointestinal tract, the alveolar-capillary barrier, wound surfaces on the skin. Then the substance enters the bloodstream, is partially fixed on the surface of red blood cells and endothelial cells. It does not stay in the blood for a long time, because within a few minutes the protein residues are destroyed by proteolytic enzymes. Further toxic effects are associated with damage to various organs and tissues.
In case of poisoning, ricin has cytotoxic and cytostatic effects. The mechanism of the substance’s influence on the cell is divided into 3 phases. In the first phase, the toxin is fixed on the cell membrane. Then the substance penetrates into the cell by endocytosis. This process can be accelerated with an increase in substances in the blood that enhance the permeability of biological membranes. At the third stage, cell damage occurs.
Ricin has the strongest effect on the large ribosome subunits responsible for protein synthesis on the information RNA matrix. The toxin binds to certain zones of ribosomes that provide interaction with elongation factors. As a result, the processes of synthesis and elongation of protein chains are disrupted, which is why the cell dies. The cytotoxic effect is enhanced by the activation of proteolytic enzymes by ricin and the induction of destruction of cellular proteins.
In case of ricin poisoning, the mechanism of autotoxic action plays an important role. Small doses of ricin can activate the process of cell division, especially T-lymphocytes. A large number of immune cells against the background of the general intoxication effect can attack the body’s own tissues by the type of autoimmune reactions. At the same time, other components of the phagocytosis system are activated, tissue autopoiesis occurs.
Clinical manifestations depend on the way ricin enters the body. Most often there is an oral route of poisoning with a toxin. In this case, symptoms occur after 10-12 hours. Suddenly there are severe pains and pains all over the abdomen, which resemble colic or acute surgical pathology. Pain syndrome is accompanied by nausea, vomiting, multiple diarrhea. With a deep lesion of the intestinal wall, blood impurities are visible in the feces.
Following intestinal symptoms, there are general signs of intoxication. Patients suffer from fever, headaches, extreme thirst and dehydration. The victims are in a state of depressed consciousness, may experience hallucinations. Their blood pressure decreases, seizures occur, the volume of urine decreases due to kidney damage. When the liver is involved in the process, acute toxic hepatitis occurs, accompanied by jaundice.
When ricin gets on the wound surfaces, an intoxication syndrome is observed, a deep ulcer appears at the site of the lesion, which does not heal for a long time. Deaths are less likely. If poisoning occurred when inhaling the toxin, the symptoms manifest themselves by damage to the lungs and bronchi: painful cough, pain and burning in the chest, shortness of breath with wheezing. The ingestion of poison in the eyes is manifested by a picture of panophthalmitis.
Poisoning with ricin is an extremely dangerous condition, which often ends with the death of the patient on the 2-7 day of the disease. Ricin is 6 times more toxic than cyanide, so such cases remain a serious problem of modern toxicology. In patients who have avoided a fatal outcome, necrosis of the lungs, liver, kidneys occur, which culminate in functional insufficiency of these organs. Eye damage is fraught with blindness.
Patients with signs of ricin poisoning are in serious condition, so the initial examination is carried out by emergency doctors or the intensive care unit. To clarify the type of toxic substance, it is necessary to find out the anamnesis of the disease, interview witnesses of the incident or relatives who have additional information. Diagnostics is carried out simultaneously with the beginning of therapeutic measures and includes the following methods:
- Instrumental examination. The diagnostic program is prescribed taking into account the leading symptoms of a particular patient. Most often, at the stage of the initial examination, abdominal ultrasound, radiography or chest CT, brain CT are performed.
- Blood test. In the hemogram, anemia, persistent neutrophilic leukocytosis, an increase in the level of lymphocytes and monocytes are observed within 2-3 weeks from the moment of poisoning. Erythrocytes have a normal shape and size, which makes it possible to exclude other types of anemia (iron deficiency, B12 deficiency).
- Coagulogram. In the acute period of poisoning, there is an increase in the level of fibrinogen, activation of the transformation of fibrinogen into dense fibrin. According to the results of the tests, signs of disseminated intravascular coagulation of blood are determined.
Ricin poisoning has no pathognomonic symptoms, therefore it requires differentiation with other plant and synthetic poisons. With gastrointestinal syndrome, it is necessary to exclude surgical diseases of the abdominal cavity:
- acute appendicitis;
- thrombosis of mesenteric vessels;
- necrotic enterocolitis.
With hematuria, differential diagnosis is performed with urolithiasis, kidney or bladder cancer.
First aid to the victim is provided even before hospitalization. If a person has eaten the seeds recently, it is necessary to rinse the stomach. To do this, give plenty of salted drink and cause vomiting. Such actions can be carried out if the patient is conscious, does not suffer from indomitable vomiting and diarrhea. If the toxin gets into the eyes or on the skin, the affected area is washed under running water. Then the patient is hospitalized to the emergency department as soon as possible.
There are no specific antidotes for ricin poisoning. Given the rapid disintegration of the substance in the blood, extracorporeal detoxification methods are ineffective. The basis of treatment is pathogenetic therapy, which is aimed at maintaining the vital functions of the body, correcting the organ complications that have arisen. Symptomatically, analgesics, antipyretic drugs, infusion solutions of glucose and electrolytes are used.
Prognosis and prevention
Given the high toxicity, the prognosis for ricin poisoning is unfavorable. There is a high probability of death in the acute period of the disease, with successful withdrawal from intoxication, long-term consequences from the lungs, liver, gastrointestinal tract and other organs are observed. To prevent dangerous conditions, it is necessary to explain to children the rules of behavior with plants, exclude the consumption of berries and seeds of unknown origin.