Overview of Liver Biopsy
A liver biopsy is the best way doctors can diagnose a range of different liver conditions. This involves taking a small sample of liver tissue and examining it for signs of damage or disease. This process has been used since 1883, when it was first performed by Paul Ehrlich, and has since been improved and honed to become a safe and important tool for doctors treating various liver diseases.
These conditions might include chronic hepatitis (a long-term inflammation of the liver), cirrhosis (scarring of the liver due to long-term damage), storage diseases (conditions where harmful substances build up in the body, including the liver), unexplained liver enlargement, and liver injury caused by certain drugs.
A liver biopsy is also used as a tool to predict the progression of certain diseases like nonalcoholic steatohepatitis (known as NASH, it’s a type of fatty liver disease) and hemochromatosis (a condition where too much iron builds up in the body) as the assessment of scar tissue helps understand the severity of these conditions.
Moreover, this test is crucial in directing the treatment approach, especially in autoimmune hepatitis (a disease in which the body’s immune system attacks the liver). The test helps track how active the disease is and whether the treatment is working effectively.
There are several ways a liver biopsy can be performed including through the skin (percutaneous), a vein (transvenous), through a small hole in the skin and muscle of the abdomen (laparoscopic), or packed (plugged) biopsy techniques. The best method depends on the patient’s individual medical situation, such as the risk of bleeding or the need for a targeted biopsy.
Even though there are non-invasive markers, which are tests that do not need a biopsy, a liver biopsy is still a crucial tool. This is because it provides a detailed look at the liver tissue, which is vital for accurate diagnosis and effective treatment planning.
Why do People Need Liver Biopsy
A liver biopsy is a procedure that helps diagnose a variety of liver conditions. It’s used to figure out the cause of different liver diseases, like long-lasting (chronic) hepatitis or cirrhosis. A biopsy can help in understanding the cause of unexplained liver size increase (hepatomegaly) or unusual levels of liver enzymes. It is also beneficial in analyzing abnormal liver enzymes after liver transplant, irregularities in the liver, blocked bile flow within the liver (intrahepatic cholestasis), and liver injury caused by drugs.
This procedure essentially has three main uses:
1) Diagnosis: When liver tests are abnormal and the cause isn’t clear, a liver biopsy can help reveal what’s wrong. For example, it can help distinguish between autoimmune hepatitis and NASH (a liver disease caused by fat buildup) in overweight patients with abnormal liver tests and positive autoimmune markers. A liver biopsy can also detect Wilson’s disease, an inherited disorder that leads to copper accumulation in the liver. In some tricky situations, a biopsy can differentiate between liver cancers or after a transplant, to find out the cause of abnormal liver function.
2) Prognosis: A liver biopsy can be used to predict the outcome of some liver diseases. For instance, in NASH, if a biopsy shows advanced liver fibrosis (scarring) or cirrhosis (late-stage scarring), it could indicate a poor outlook. The presence of cirrhosis in diseases like hemochromatosis (an iron overload disorder) implies an increased chance of developing liver cancer. Even though non-invasive markers are mostly used now, finding fibrosis can significantly predict the outlook for patients with chronic liver ailments like hepatitis C.
3) Treatment: A liver biopsy is critical for patients being treated for autoimmune hepatitis, which often involves steroids and other similar drugs. Active liver disease, as shown in a biopsy, carries a high chance of return if treatment is stopped. Improvement in biopsy results can show that the patient is responding to treatment, making biopsies a good way to monitor drug effectiveness.
When a Person Should Avoid Liver Biopsy
There aren’t many reasons why a doctor wouldn’t perform a liver biopsy. However, depending on how the biopsy is done and who is doing it, there are some specific situations when it might not be recommended.
For instance, it may not be suitable under the following situations:
– If the patient is unwilling or unable to cooperate: It’s important that patients fully understand the procedure and agree to it. If they cannot or do not want to cooperate, this can increase the risk of complications. In such cases, if a liver biopsy is still necessary, it might be done under anesthesia.
– If there is an increased risk of bleeding: As a rule, a liver biopsy usually isn’t tried if the patient’s INR (a measure of how quickly blood clots) is over 1.5, or if the count of platelets (small blood cells that help stop bleeding) is less than 60,000. If these numbers are not within normal ranges, doctors may need to correct these issues before attempting a biopsy.
– If there are vascular tumors in the liver: Vascular tumors refer to growths in the liver’s blood vessels. Doing a liver biopsy in this situation has a higher risk of causing bleeding.
Similarly, a liver biopsy can also be more complex and risky under other certain conditions:
– Patients with ascites: Ascites is a build-up of fluid in the abdomen, which can increase complications associated with a percutaneous biopsy (a type of biopsy where a needle is inserted through the skin). In these cases, a biopsy is usually done via a vein (transvenous biopsy).
– Patients who are very obese: The liver biopsy procedure can be more difficult due to the extra fat tissue. In these situations, like with ascites, the preferred method is usually via a vein (transvenous biopsy).
Equipment used for Liver Biopsy
When doctors need to take a small sample of liver tissue to examine it closely, they can use two types of needles: aspiration or cutting needles. These normally range in size from 16 to 18 gauge. There are also new and improved versions of these needles that can do the job better. With aspiration needles, doctors usually use a syringe to apply suction and take out a small bit of liver tissue. But this method can sometimes break up the tissue and not give enough of a sample, especially in patients who have a condition called cirrhosis, which is when the liver is damaged and scarred.
Cutting needles work a bit differently. They have an inner needle and an outer sheath that cuts. When the sheath moves past the needle, it cuts and traps liver tissue inside the hollow needle. The cutting method tends to work better for getting good samples and is less likely to break up the tissue. Plus, the procedure is quicker and has less chance of complications than the suction method. It might be the preferred option when safety and speed are important.
Preparing for Liver Biopsy
Liver biopsies, which are tests to check for liver disease, are usually done in a place where you don’t need to stay overnight, like a doctor’s office or clinic. However, it’s important for this location to be close to a hospital, lab, and place where blood is stored, just in case there are any emergencies.
Doctors will schedule the biopsy to be done in the morning and then have you stay at the office or clinic for about 4 hours afterwards. This is so they can make sure there are no problems and give you any needed care while all the medical staff are there.
Before the biopsy, the doctor will ask you about your health history and do a physical check-up. If you’re on any blood-thinning medications, you’ll usually have to stop taking them before the biopsy. The exact time when you should stop these medications depends on what type and purpose of the drug you’re on. Doctors commonly ask patients to do this 5 days before the biopsy. They do this to lower the chance of bleeding after the biopsy.
They’ll also take some of your blood to do tests and make sure your blood cells that help clotting are in the normal range. If they’re not, it can increase the risk of bleeding after the biopsy. For a liver biopsy, patients typically don’t need to take antibiotics beforehand.
Before the biopsy, it’s usually OK to have a small snack about 4 hours beforehand. Doctors have different opinions on how long you should go without eating before the procedure. If you’re nervous about the procedure, the doctor might give you medicine to make you feel relaxed, and in this case, you might need to go without food for a longer time. Don’t forget, the doctor should explain what will happen during the biopsy and ask you to sign a form that says you understand and agree to the procedure.
How is Liver Biopsy performed
Your doctor may need to take a small sample of your liver (a biopsy), for which there are a few common methods. Which method is used can depend on your particular health situation.
1. Percutaneous Biopsy: This is a common method for taking a liver biopsy. It is done by inserting a thin needle through your skin (after it’s been numbed) into your liver. The doctor might use their hands to feel where to insert the needle, or they might use an imaging machine (like an ultrasound) to guide the placement of the needle.
2. Transvenous Biopsy: This method is often used if a percutaneous biopsy might be risky due to other health conditions you may have. In this procedure, a small tube is inserted into a vein in your neck. The tube is then guided to your liver using an X-ray machine, and a biopsy needle is sent down the tube to take a sample. This method can also help doctors get detailed information about the blood flow in your liver.
3. Laparoscopic Biopsy: This type of biopsy is done when you are already having another type of surgery, or if the other biopsy methods didn’t provide a clear enough result. In this method, a small, lighted tube with a camera is used to see inside your body. The tube is inserted through a small cut in your abdomen and special tools are used to take the biopsy.
4. Plugged Biopsy: This is a modified form of the percutaneous biopsy that can be used for patients who have a high risk of bleeding, like those with decreased blood clotting. In this method, after the biopsy is taken, a substance is inserted into the path where the needle was, which helps stop any bleeding that could occur.
Remember, all of these techniques are designed to safely obtain a small sample of your liver tissue. These samples can provide valuable information about your liver health and help guide your doctor in deciding the right treatment for you. The choice of which method to use will be made by your doctor, taking into account your individual health conditions and preferences.
Possible Complications of Liver Biopsy
Liver biopsy or liver tissue sampling is generally safe when conducted by experienced professionals. In some large studies, the overall rate of severe side effects was around 1%. In another study, the overall chance of death due to the procedure was 0.2%. The typical signs of complications that might need overnight hospital stay are severe abdominal or shoulder tip pain not eased with a single dose of strong pain relief, low blood pressure, or rapid heartbeat after the procedure.
Pain is the most reported side effect after a liver biopsy and is seen in up to 84% of patients. This pain is most common at the biopsy site or the right shoulder and is typically controlled with pain relievers. However, if the pain is severe and continues, this could be a sign of more serious issues, like bile leakage into the abdomen or bleeding, and may require further testing.
Bleeding complications are another concern. The risk of fatal bleeding in patients without cancerous diseases is extremely low, around 0.04%, and the risk of a nonfatal bleed is even lower, at 0.16%. In those with cancer, the risk of nonfatal bleeds increases slightly. There are three main types of bleeding complications: free internal bleeding, liver and skin blood clots, and bleeding into the bile.
Free internal bleeding might happen due to liver injury, like in deep breathing during the biopsy procedure, or due to an accidental puncture of a major liver blood vessel. Symptoms can include instability of body functions, severe abdominal pain, and a quick drop in blood count. This is a critical situation requiring immediate medical attention, and the patient would be admitted, revived, with the possibility of a radiological intervention to stop the bleeding. In rare cases, surgical intervention might be needed.
Blood clots in the liver and under the skin can happen even if the patient is without symptoms. It presents often as pain, rapid heartbeat, a slight drop in hemoglobin (red blood cells), and a rise in liver enzymes. If large, they can cause tenderness and swelling in the upper right abdomen and abnormal results on a CT scan. Most patients can be managed without surgery, and only in rare situations are medical interventions deemed necessary.
Bleeding into the bile, which causes gastrointestinal bleeding, biliary pain, and jaundice, is typically because of arterial, but can be venous in patients with pre-existing conditions resulting in high blood pressure within the liver. It can range from hidden to massive hemorrhage. This bleeding complication typically presents after about 5 days with gradual erosion of a blood clot or an abnormal blood-filled sac into the bile duct. Treatment will depend on the severity.
Transient bacteremia, a temporary presence of bacteria in the bloodstream, is usually no cause for concern, except in certain patients with specific diseases like obstructive jaundice, a liver condition causing bile to build up or in the aftermath of a transplant. Antibiotic treatment can be considered on a case-by-case basis.
Bile peritonitis, a condition where bile leaks into the abdomen, can happen with an accidental puncture of the gallbladder or in patients with blocked and enlarged bile ducts. This usually shows as abdominal pain, fever, and an increase in white blood cells, but in some patients, this condition may not cause any pain. Treatment generally includes intravenous fluids and antibiotics. In rare cases, endoscopic procedures or surgery may be needed.
Lastly, other rare complications could include heart issues particularly in patients with existing heart conditions, abnormal connections between arteries and veins, and a buildup of air between the lung and chest wall. Carcinoid crisis, a severe episode of flushing, breathing difficulty, and low blood pressure, can also occur after the biopsy procedure.
What Else Should I Know About Liver Biopsy?
After a liver biopsy procedure, there are certain things that need to be monitored:
Patient’s Condition:
The patient is usually rested on their right side, and observation times can vary depending on the healthcare center, ranging from 1 to 6 hours. Generally, guidelines recommend that patients be observed for a period of 2 to 4 hours. Within this time, vital signs such as heart rate, blood pressure, and temperature are frequently checked to ensure patient’s wellbeing.
The majority of complications from a liver biopsy typically occur within the first few hours post-procedure or within a day. Hence, it’s suggested that a responsible individual stays with the patient overnight. If there are any complications linked to the biopsy, like severe pain that cannot be managed with typical pain medications, a hospital stay might be necessary.
The Sample Quality:
Liver diseases vary in their presentation, which means that a biopsy sample might not always show the full picture of the disease. Therefore, it is crucial to obtain a good quality sample that will provide enough information for examination.
This usually means that the specimen should be big enough to allow a detailed view of the liver tissue (parenchyma) and several small areas called portal tracts. If a larger sample is obtained, this increases the chances of accurate diagnosis but it also slightly raises the risk of complications.
Experts believe a sample providing a view of about 11 portal tracts and around 2 cm long is sufficient for evaluation. If a satisfactory specimen isn’t obtained in the first two attempts, a different approach might be required.
The key to quality liver biopsy is getting a sample that is long and wide enough. And while there are growing noninvasive methods for assessing the liver, histological (tissue-based) examination will continue to be vital in diagnosing disease. It’s considered a safe procedure when carried out by experienced staff and usually results in minimal complications.
