OVERVIEW
Liver injury caused by drugs, toxins, chemicals, etc. manifests as malaise, right upper abdominal discomfort, jaundice, nausea and vomiting, liver enlargement, etc. Causes include drugs, industrial chemicals, heavy metal exposure, and toxic events Elimination of the cause of the disease, use of liver-protecting medications, symptomatic and supportive treatment
Definition
Chemical liver injury is liver damage caused by drugs, toxins, and chemicals.
These chemicals can directly damage liver cells or indirectly cause liver injury by affecting the function and structure of liver cells.
The severity of chemical liver injury can range from mild liver function abnormalities to severe liver failure.
Typing
It is categorized into the following types based on the cause.
Drug-Induced Liver Injury (DILI): Liver injury caused by drugs, including prescription drugs, over-the-counter drugs, and herbal medicines.
Toxic Liver Injury (TLI): Liver injury caused by various toxic substances such as heavy metals, organic solvents, mycotoxins, etc.
Chemical substance liver injury: Liver injury caused by some chemicals such as industrial products and cosmetics.
Morbidity
The epidemiology of chemical liver injury varies according to a variety of factors such as region, culture, and drug use habits.
Drug induced liver injury (DILI) accounts for about 10% of all reported cases of liver injury.
In Western countries, DILI is the leading cause of acute liver failure, accounting for 50% of all cases of acute liver failure.
The prevalence of drug-related liver injury varies widely across studies, ranging from 1/10,000 to 1/100,000.
High-risk medications include: over-the-counter pain relievers, antibiotics, antiepileptic drugs, and anti-tuberculosis drugs.
Etiology
Chemical liver injury occurs when a drug, toxin, or chemical causes damage to the liver.
Causes
Common substances that cause chemical liver injury include prescription medications (e.g., antibiotics, antivirals, anticancer drugs, etc.), over-the-counter medications (e.g., pain relievers, antipyretics, etc.), herbal remedies, toxins (e.g., heavy metals, organic solvents, mycotoxins, etc.), and chemicals (e.g., industrial products, cosmetics, etc.).
Predisposing Factors
Risk or predisposing factors include genetic factors, age, gender, alcohol intake, drug interactions, history of liver disease, obesity and malnutrition.
Genetic factors: Individual genetic differences may lead to different susceptibility to chemical liver injury.
Age: Elderly people and children have weaker liver detoxification and are more susceptible to chemical liver injury.
Gender: female patients may be more sensitive to certain drugs and prone to drug-related liver injury.
Alcohol: Long-term heavy drinking can impair liver function and increase the risk of chemical liver injury.
Drug interactions: Simultaneous use of multiple drugs may lead to drug interactions and increase the risk of liver injury.
History of liver disease: Patients with existing liver disease have weakened liver detoxification capacity and are more likely to develop chemical liver injury.
Obesity and malnutrition: Obesity and malnutrition may affect liver function and increase the risk of chemical liver injury.
Pathogenesis
The pathogenesis of chemical liver injury includes direct toxic effects and immune-mediated injury.
Direct toxicity
Some chemicals can directly damage the structure of liver cells, leading to liver cell death. For example, excessive alcohol and certain drugs are metabolized in the liver to produce toxic intermediates that can damage hepatocytes and lead to liver injury.
Immune-mediated damage
Some chemicals may trigger an immune response that can lead to liver damage. For example, metabolites from certain drugs that are metabolized in the liver can bind to liver cells and form antigens, which in turn trigger the immune system to attack liver cells.
Symptoms
Chemical liver injury is mainly characterized by weakness, right upper abdominal discomfort, jaundice, nausea and vomiting, and liver enlargement.
Main Symptoms
Fatigue and weakness: Patients may feel fatigue and generalized weakness, which is one of the most common symptoms of chemical liver injury.
Upper Right Abdominal Discomfort: Patients may experience discomfort, pain or pressure in the upper abdomen, especially in the right upper abdomen (where the liver is located).
Jaundice: Due to the disturbance of bilirubin metabolism as a result of liver injury, patients may develop yellowing of the skin and sclera.
Nausea and vomiting: Abnormalities in liver function may lead to digestive disturbances manifested as nausea and vomiting.
Dark or bloody stools: Liver injury may affect blood clotting, leading to gastrointestinal bleeding.
Hepatomegaly: The liver may increase in size due to inflammation, necrosis and edema of liver cells.
Cholestasis: Liver injury may affect the secretion and discharge of bile, leading to cholestasis, which manifests as symptoms such as itchy skin, darkened urine and lightened stools.
Complications
Liver failure: severe liver injury may lead to severe liver insufficiency, which may progress to liver failure.
Cirrhosis: long-term liver injury may lead to liver fibrosis, which eventually develops into cirrhosis.
Hepatic encephalopathy: Liver injury causes the liver to be unable to metabolize toxins properly, triggering hepatic encephalopathy.
Infection: The immune system is impaired in liver injury, while endotoxins may cause intestinal paralysis, resulting in infection.
Other organ failure: When liver injury is severely combined with liver failure, it can also be combined with other organ failure, such as kidney failure.
Consultation
Patients with chemical liver injury need to pay attention to the following conditions when seeking medical treatment:
Department of Medicine
Gastroenterology
After taking or being exposed to drugs, toxins, or chemicals, if symptoms such as fatigue, discomfort in the right upper abdomen, jaundice, nausea and vomiting, ascites, and liver enlargement occur, the patient should go to the Department of Gastroenterology.
Preparation for medical treatment
Preparing for your visit: registering, preparing your documents, FAQs
Tips for the doctor
Gather medical history: Organize information on the time of onset of symptoms, the evolution of symptoms, and past medical history.
Gather a history of drug and chemical exposure: Prepare a list of recently used drugs, chemicals, or toxins, including the name of the drug, dosage, usage, and time of use.
Bring relevant test reports: If relevant tests have been performed, bring the test reports with you to the appointment.
Checklist to prepare for medical consultation
Symptom list
Pay particular attention to the time of onset of symptoms, special manifestations, etc.
Any symptoms of loss of appetite, anorexia, nausea, vomiting, epigastric discomfort?
Is there any fatigue, weakness, weight loss?
Any bleeding, coma, drowsiness?
Any yellowing of the skin, itching of the skin, rash, lightening of fecal color?
Time of onset and duration of the above symptoms, and are they getting progressively worse?
Any fever, joint aches and pains?
Any hypotension, shock (e.g., pallor, cold extremities, weakness, fainting)?
Medical History Checklist
Is there any chronic drug use or exposure to toxic substances?
Any history of chronic medical conditions such as liver disease, cardiovascular disease, diabetes?
Is there any history of pregnancy, alcohol consumption (excessive drinking or alcoholism)?
Is there any family history of liver disease or other related diseases?
Any history of allergies, such as allergies to certain medications or foods?
Checklist
Test results from the past six months, which can be brought to the doctor’s office
Laboratory tests: liver function, coagulation function, hepatitis virus test, etc.
Imaging tests: abdominal ultrasound, CT, magnetic resonance imaging, etc.
Diagnosis
Chemical liver injury is an exclusive diagnosis, and the diagnosis mainly relies on medical history, clinical manifestations and relevant auxiliary examinations, while viral hepatitis, alcoholic liver disease, autoimmune liver disease and other liver diseases should be excluded.
Diagnostic basis
Medical history
The patient has a history of exposure to or use of drugs, chemicals or toxic substances that may cause liver injury.
Clinical manifestations
The patient presents with symptoms of liver damage of varying degrees, such as malaise, jaundice, loss of appetite, nausea, vomiting, epigastric pain, and hepatomegaly.
Laboratory tests
Liver function: elevated alanine aminotransferase (ALT), alanine aminotransferase (AST), bilirubin and other indicators suggest that the disease may be present.
Hepatitis virus test: Hepatitis virology has the value of exclusion diagnosis.
Virus test: cytomegalovirus, EBV, herpes simplex virus, varicella-zoster virus positive test has the value of exclusion diagnosis.
Coagulation function: prolonged prothrombin time and decreased coagulation factors suggest coagulation dysfunction.
Exclusion of other causes
This is an exclusionary diagnosis and other liver diseases such as viral hepatitis, alcoholic liver disease, autoimmune liver disease need to be excluded.
Differential diagnosis
Chemical liver injury is mainly differentiated from the following diseases.
Viral hepatitis: Detect antibodies and antigens related to viral hepatitis, such as hepatitis B surface antigen and hepatitis B core antibody, etc. through serologic examination.
Alcoholic liver disease: differentiated by the patient’s history of alcohol consumption, medical history, and biochemical test results (e.g., GGT, AST/ALT ratio, etc.).
Autoimmune liver disease: through serologic examination, autoantibodies such as anti-nuclear antibody (ANA) and anti-smooth muscle antibody (SMA) are detected, which are combined with clinical manifestations for differentiation.
Steatohepatopathy: differentiated according to the patient’s body weight, lipid level, history of diabetes and other risk factors, combined with the detection of fatty deposits on liver ultrasound, CT or MRI.
Metabolic liver disease: identify metabolic liver diseases such as hemochromatosis and Wilson’s disease based on the patient’s genetic history and family history, combined with the detection of relevant metabolites, such as iron and copper.
Treatment
Aim of treatment: protect the liver, restore liver function, reduce complications.
Treatment principle: eliminate the cause of disease, maintain the balance of internal environment, use hepatoprotective drugs, symptomatic treatment and supportive therapy.
Elimination of causes
Once chemical liver injury is diagnosed, the first task is to stop using drugs that cause liver injury or avoid contact with toxic chemicals.
Medication
Hepatoprotective drugs
Reduced glutathione (GSH)
Reduce liver injury by inhibiting lipid peroxidation and scavenging free radicals.
Silymarin
For mild to moderate hepatocellular injury type DILI and mixed DILI in which inflammation is mild.
May reduce liver injury.
Glycyrrhetinic acid
Indicated for mild to moderate hepatocellular injury in DILI and mixed DILI with more severe inflammation.
It has the effect of lowering serum aminotransferase level and anti-lipid peroxidation.
Magnesium glycyrrhizinate can be used in acute hepatocellular injury type DILI or mixed DILI.
Polyene phosphatidylcholine
Has a protective, stabilizing, and repairing effect on biological membranes.
S-Adenosylmethionine
Has a role in transsulfuration, which promotes the production of cysteine and glutathione to counteract free radical damage to the liver.
It has the function of synthesizing taurine, which can increase the solubility of bile acid and prevent intrahepatic cholestasis.
N-Acetyl Cysteine (NAC)
For heavy DILI, early acute liver failure.
The earlier it is used, the better.
Contraindicated for children 0-2 years old.
Has the effect of scavenging free radicals.
Ursodeoxycholic Acid (UDCA)
For cholestatic DILI.
Has immunomodulatory effects.
Also has the effect of improving the secretion of hepatocytes and bile duct cells.
Supplementation of coagulation factors and albumin
In severe liver disease, the liver’s synthetic function is impaired, plasma transfusion is needed to supplement clotting factors in time, and the necessary albumin needs to be supplemented.
Artificial liver
Applicable to severe and extremely severe liver injury when artificial liver is needed to replace part of the liver function, provide patients with a good internal environment and promote liver repair.
Liver transplantation
Liver transplantation can be performed if there is massive necrosis of liver cells and liver function cannot be restored, which is a life-threatening condition.
Symptomatic treatment
Diuretics for edema, antispasmodic and analgesic for abdominal pain, nutritional supplements, and medications to improve loss of appetite.
Prognosis
Cure
Most patients with chemical liver injury can recover gradually with timely detection and management of chemical liver injury. Prognostic factors for chemical liver injury usually include the degree of injury, etiology, early diagnosis and treatment.
Mild to moderate injury: most patients can gradually recover their liver function after stopping exposure to the causative factors and undergoing appropriate treatment, and the prognosis is generally good.
Severe injury: Some patients may develop acute liver failure, which requires aggressive treatment, and for some severe patients, liver transplantation may be necessary. In these cases, the prognosis may be poorer.
Chronic injury: Long-term exposure to disease-causing factors may lead to chronic liver injury, which further develops into cirrhosis, liver failure and other serious complications, and the prognosis may be poorer.
Prognostic factors
According to the literature, the prognostic factors of chemical liver injury include the degree of injury, etiology, early diagnosis and treatment.
Degree of injury: the more severe the injury, the worse the prognosis.
Etiology: Some drugs and chemicals may lead to more severe injury, such as liver injury caused by overdose of over-the-counter painkillers.
Early diagnosis and treatment: Early detection and cessation of exposure to the causative agent and prompt and appropriate treatment can help improve prognosis.
Harmful
The prognosis is usually better when patients seek timely medical attention and take appropriate measures, such as stopping harmful drugs or chemicals and using liver-protecting treatments.
In cases of severe liver injury or failure to seek timely medical attention, patients may develop complications of hepatic encephalopathy and liver failure, and long-term losses may develop into cirrhosis, which is life-threatening.
Daily routine
Patients with chemical liver injury need to maintain a healthy lifestyle and diet in their daily life, avoid exposure to hepatotoxic substances, and exercise appropriately in order to strengthen the body’s immunity and contribute to liver recovery. Strictly follow the doctor’s recommendations for review, timely assessment and adjustment of treatment plan.
Daily Management
Dietary adjustments: Maintain balanced nutrition, avoid high-fat, high-sugar, high-salt and high-protein foods, and eat more fresh vegetables, fruits and a small amount of high-quality protein foods.
Avoid exposure to toxic chemicals: e.g. pesticides, toxic gases, etc. to reduce the risk of occupational exposure.
Use medication appropriately: Follow medical advice when using medication, especially medications that are potentially toxic to the liver, such as certain antibiotics and painkillers.
Maintain a good work routine: Ensure adequate rest and sleep, and avoid late nights and strenuous work.
Stop smoking and drinking: Stop smoking and drinking to reduce the burden on the liver.
Follow-up and review
Patients need to monitor liver function regularly.
The review time and items should be determined according to individual condition and doctor’s recommendation. In general, those with mild liver injury can be reviewed every 3-6 months; for those with severe liver injury, the review period should be shortened and carried out according to the doctor’s recommendation.
Prevention
Use medication appropriately, follow doctor’s advice and avoid unnecessary drug abuse.
Pay attention to personal protection and avoid occupational exposure, such as wearing masks and gloves.
Focus on improving lifestyle habits and maintaining a healthy diet and routine.
Enhancing physical exercise helps improve physical fitness and strengthen the function of the immune system, which has a positive effect on liver recovery and prevention of liver injury.
Weight control helps reduce the risk of liver disease.
Follow your doctor’s treatment recommendations and prescriptions, have regular reviews and adjust your treatment plan according to your doctor’s advice.
Maintaining a good state of mind and reducing psychological stress will help your body recover.