Arsenic poisoning

　　Arsenic poisoning is generally caused by excessive dosage of arsenic-containing drugs, or by accidental ingestion of poisoned rats, snails, insecticides, as well as fruits and vegetables sprayed with such insecticides, and meat of birds and animals that have been poisoned. Arsenic trioxide (also known as arsenic, red and white orpiment, etc.) is commonly used in northern rural China as a seed dressing and insecticide, with a high toxicity. Its pure form looks similar to salt, sugar, flour, and gypsum, and can cause poisoning due to accidental ingestion or misuse. There are also cases of poisoning due to drinking water and food contaminated with arsenic trioxide. Maternal poisoning can lead to poisoning in the fetus and infants.

　　Peripheral neuritis often occurs with infection or inflammation in most cases and is also known as peripheral neuropathy. The disease is caused by peripheral nerve lesions of various causes (including cranial nerves and spinal nerves), manifested as abnormal sensory, motor, and autonomic nerve function within the range of the damaged nerves. It is a common disease in the nervous system, occurring at any age.

　　Early symptoms of acute arsenic poisoning are commonly gastrointestinal symptoms, such as dryness, pain, burning, and tightness in the mouth and throat, hoarseness, nausea, vomiting, difficulty in swallowing, abdominal pain, and diarrhea, etc. Initially, the vomit contains stomach contents and rice water, followed by the mixture of blood, mucus, and bile, sometimes containing small pieces of unabsorbed arsenic compounds; the vomit may have a garlic-like smell. Severe cases may be very similar to cholera, starting with the passage of large amounts of watery stools, which later become bloody or mixed with blood streaks. Dehydration, acidosis, and shock may occur quickly, accompanied by headache, dizziness, irritability, delirium, toxic myocarditis, polyneuritis, etc. A few patients may have epistaxis and skin hemorrhage. Severe children may develop respiratory, circulatory, liver, kidney, and central nervous system failure and central nervous system lesions within 24 hours to several days after poisoning, with symptoms such as respiratory distress, convulsions, and coma. A few patients may develop shock within 20 minutes to 48 hours after poisoning, even death, while gastrointestinal symptoms are not prominent. Children may have an attack of porphyria and strong positive urine coproporphyrin.

　　Hydrogen arsenide poisoning often has hemolytic phenomena. In subacute poisoning, symptoms of polyneuritis appear, such as abnormal sensation in the limbs, starting with pain and numbness, followed by weakness and debility, and eventually complete or incomplete paralysis, with wrist drop, foot drop, and disappearance of tendon reflexes; or difficulty in swallowing, speech and breathing disorders, sometimes accompanied by skin redness or erythema due to vascular dysregulation. Chronic poisoning patients often show weakness, anorexia, occasional nausea and vomiting, constipation or diarrhea, and may also appear leukopenia and thrombocytopenia, anemia, red blood cell and bone marrow cell production disorders, hair loss, stomatitis, rhinitis, nasal septum ulceration, perforation, skin pigmentation, and may have desquamative dermatitis. The skin of the palms and toes may become hyperkeratotic, the nails lose luster and flatness, become thin and brittle, and appear white transverse stripes. There may also be liver and myocardial damage. Arsenic poisoning patients have increased arsenic in hair, urine, and fingernail (toenail) arsenic content. Children who ingest a large amount of arsenic may be found to have X-ray-invisible substances in the gastrointestinal tract during abdominal X-ray examination.

　　Protection should be given to workers who have long-term contact with arsenic-containing substances.

　　1. Arsenic poisoning is usually ingested through the digestive tract, so attention should be paid to daily diet and avoiding contact with these heavy metal substances is the fundamental method of preventing poisoning.

　　2. In terms of diet, it is advisable to avoid foods that harm the liver and other organs, and to adopt a light diet. Eat more blood-nourishing foods such as jujube, animal liver, etc., which are rich in vitamins and antioxidants. Eliminate the patient's anxiety and pessimistic mood. Encourage the patient more, and give them confidence.

　　Based on the occupational history of close contact with arsenic compounds for a longer period of time, the appearance of dermatitis, hyperkeratosis of the skin, hyperpigmentation of the skin, and clinical manifestations mainly of the digestive system and nervous system, referring to the laboratory test results such as arsenic levels, comprehensive analysis, excluding diseases caused by other reasons; diagnosis can be made.

　　Symptoms such as headache, dizziness, insomnia, frequent dreams, fatigue, poor digestion, weight loss, discomfort in the liver area, etc.; arsenic levels exceed the local normal reference values.

　　It is advisable to drink mung bean soup after arsenic poisoning.

　　In common diet, sea products such as seaweed, scallops, shrimps, etc., also have a high content of arsenic, so seafood products should be controlled in diet. If a large amount of seafood is eaten, try not to drink fruit juice again.

　　For acute poisoning by mouth, induce vomiting immediately, and wash the stomach with warm water or normal saline, 1% sodium thiosulfate solution, etc. (Even if the oral intake has exceeded 6 hours or vomiting has occurred, the stomach should still be washed carefully.) Then, take fresh prepared ferric oxide detoxifying agent (mixture of 12% ferrous sulfate solution and 20% magnesium oxide suspension, mixed in equal amounts before use, shaken before use), so that it combines with arsenic to form insoluble ferric arsenate, take one spoon every 5-10 minutes until vomiting, stop administration. If this medicine is not available, active carbon suspension, milk, or egg white water can be given, followed by sodium sulfate or magnesium sulfate to induce diarrhea. Hemodialysis may be necessary if necessary. At the same time, effective detoxifying agents such as sodium thiosulfate, sodium sodium bisulfite, sodium thiosulfate, and aminopyrine, etc. (dosage and method are the same as mercury poisoning) should be rapidly selected. Intravenous fluid replacement promotes the excretion of toxins and corrects the imbalance of water and electrolytes. Symptomatic treatment should be given for gastrointestinal symptoms, neuritis, convulsions, and liver and kidney damage. If there is severe hemolysis, blood transfusion can be performed. When there is severe abdominal and muscle pain, calcium gluconate can be given intravenously slowly.

　　Chronic poisoning can be treated with aminopyrine. Before taking the medicine, collect 24-hour urine for arsenic quantification. If it is > 66.5 μmol (50 μg), it can be taken continuously for 5 days. After 10 days, according to the speed of arsenic decrease < 66.5 μmol/24h (50 μg/24h), another 1-2 5-day courses can be given. Sodium thiosulfate injection 10% can also be given intravenously once a day, 10-20 mg/kg each time. Other treatments are symptomatic.