Which Tests Find the Cause of Hepatitis? Viral Markers, Liver Panels and Ultrasound

The message on the patient portal was only one line long: your liver enzymes are raised, please book a follow-up. No explanation, no context, just a number in red beside a word most people associate with something dramatic. By the time the appointment arrives, the internet has offered a dozen frightening possibilities and no way to tell them apart.

The good news is that clinicians approach this in a very orderly way. The tests to find the cause of hepatitis are not a single scan or a single blood draw. They are a sequence, each result narrowing the field: first, is the liver actually inflamed and how badly; second, is a virus responsible; third, if not a virus, what else could it be; and finally, has any lasting damage been done.

This explainer walks through that sequence in plain language, so the numbers on the report make sense before anyone sits down to discuss them.

What actually happens when doctors run tests to find the cause of hepatitis

Hepatitis is a description, not a diagnosis. The word simply means inflammation of the liver, and inflammation can be triggered by viruses, alcohol, medicines, the body’s own immune system, fat build-up, iron or copper overload, or a sudden drop in blood flow. Finding the cause is therefore a process of elimination, and it starts with a conversation rather than a needle.

The clinician will ask about alcohol, every medicine and supplement taken in the past few months, travel, tattoos or piercings, transfusions, family history of liver disease, and any illness in close contacts. This history often points the investigation in a direction before a single result comes back. A physical examination looks for yellowing of the skin or eyes, an enlarged or tender liver, and signs of long-standing liver disease such as fluid in the abdomen.

Blood tests then run in tiers. The first tier is a liver panel, a group of measurements that shows whether liver cells are leaking their contents and whether bile is flowing normally, plus a clotting test and a full blood count. If those confirm inflammation, the second tier is the hepatitis panel, a set of viral markers that checks for hepatitis A, B and C. A third tier, ordered when viruses are ruled out or the picture does not fit, screens for autoimmune antibodies, iron and copper studies, and other viruses that can inflame the liver.

Imaging sits alongside the blood work. An ultrasound scan, which uses sound waves rather than radiation, shows the size and texture of the liver and whether the bile ducts are blocked. Elastography, a related technique that measures how stiff the liver is, gives an indirect estimate of scarring. Only when all of this still leaves a question does a biopsy, the removal of a tiny sample of tissue, come into consideration. Each step is chosen by the treating team based on the step before it.

Liver function test results explained: ALT, AST, ALP and bilirubin

The liver panel, sometimes called liver function tests, is usually the first clue that something is wrong and the first result people try to decode at home. Four values do most of the work.

ALT (alanine aminotransferase) and AST (aspartate aminotransferase) are enzymes that live inside liver cells. When those cells are damaged, the enzymes spill into the bloodstream, so a rise in ALT and AST signals active injury to the cells themselves. ALT is the more liver-specific of the two; AST is also found in muscle and heart, which is why a hard workout or a muscle injury can nudge it upward.

ALP (alkaline phosphatase) comes mainly from the cells lining the bile ducts, and bilirubin is the yellow pigment produced when old red blood cells are broken down. A pattern in which ALP and bilirubin climb while ALT and AST stay closer to normal suggests the problem is with bile flow rather than the cells, pointing toward gallstones, duct blockage or certain medicines rather than classic hepatitis.

Two further values describe how well the liver is doing its job rather than how injured it is. Albumin, a protein the liver manufactures, falls when the organ has been struggling for weeks or months. The prothrombin time or INR, which measures how quickly blood clots, depends on clotting proteins the liver makes; a rising INR in acute hepatitis is one of the most important warning signs clinicians watch, because it reflects failing function rather than just leakage.

Reference ranges differ between laboratories, and a mildly raised result in one person may be normal for another, which is why MedlinePlus advises against interpreting a single value in isolation. The pattern across all the numbers, and how it changes over days, tells the story.

What tests indicate hepatitis rather than another liver problem?

A raised ALT does not automatically mean hepatitis, and a normal one does not rule it out. The first job of the treating team is to confirm that the liver is genuinely inflamed, and the second is to decide how urgent the situation is.

The hepatocellular pattern, meaning ALT and AST rising far more than ALP, is the classic signature of hepatitis. Very high values, many times the upper limit of the laboratory’s range, tend to accompany acute viral infection, medicine-induced injury or a sudden loss of blood supply. More modest elevations that persist for months are typical of chronic viral hepatitis, fatty liver disease or autoimmune disease. The size of the rise is a clue, not a verdict.

Before assuming the liver is the source, clinicians often check a creatine kinase level, which rises with muscle damage, and thyroid function, since an overactive or underactive thyroid can alter liver enzymes. Coeliac disease is another well-recognized cause of unexplained enzyme elevation, and a screening blood test may be added.

A full blood count adds context. A low platelet count can hint at long-standing liver scarring, because a stiff, scarred liver traps platelets in the spleen. Enlarged red blood cells can accompany heavy alcohol use. The clotting test discussed above is the severity marker: leakage of enzymes alone is not dangerous, but a liver that can no longer make clotting proteins is.

Timing matters too. Hepatitis is described as acute when inflammation has been present for less than six months and chronic when it lasts longer, a definition used by WHO and the NHS. Whether a first abnormal result represents a new illness or the tail end of a long, silent one is often unknown at the outset, and repeat testing over weeks is how that question gets answered.

The hepatitis panel blood test: what each viral marker means

Once inflammation is confirmed, the hepatitis panel blood test looks for the three viruses that most commonly cause it. Understanding the results requires three definitions. An antigen is a piece of the virus itself, so finding one means the virus is present. An antibody is a protein the immune system makes in response, so finding one means the body has encountered the virus at some point, recently or long ago. A nucleic acid test detects the virus’s genetic material and confirms active infection.

MedlinePlus describes the standard acute panel as containing four components. The hepatitis A IgM antibody is the type of antibody produced early in infection; its presence indicates a recent hepatitis A infection, which spreads through contaminated food and water and does not become chronic. The hepatitis B surface antigen (HBsAg) is a protein on the outer coat of the hepatitis B virus and shows current infection. The hepatitis B core antibody IgM indicates recent infection with hepatitis B. The hepatitis C antibody shows past or present exposure to hepatitis C.

Each virus has its own timeline, and testing too early can miss it. WHO reports that hepatitis B symptoms appear anywhere from 30 to 180 days after exposure, and the surface antigen typically becomes detectable within the first one to two months. For hepatitis C, the CDC notes that the virus’s RNA can be detected within one to two weeks of exposure, while antibodies usually take about eight to eleven weeks to appear. A negative panel taken shortly after a known exposure may therefore be repeated later.

The panel does not include hepatitis D, which only infects people who already have hepatitis B, or hepatitis E, which is tested separately when travel history or an unexplained acute picture suggests it. Nor does it look at other viruses such as Epstein-Barr or cytomegalovirus, which can inflame the liver during a broader illness.

Hepatitis B markers: surface antigen, core antibody and viral load

Hepatitis B generates the most confusing results because several markers are usually reported at once, and the combination matters more than any single line. WHO estimates that around 254 million people were living with chronic hepatitis B in 2022, most of them unaware, so these results are read very often.

The surface antigen, HBsAg, is the headline marker: positive means the virus is present now. If it remains positive for more than six months, the infection is classed as chronic. The surface antibody, anti-HBs, is the mirror image; it indicates immunity, either from a past infection that cleared or from vaccination. A person with anti-HBs alone, and nothing else, is protected rather than infected, a distinction that causes a great deal of unnecessary alarm.

The core antibody, anti-HBc, appears in anyone who has ever been infected and stays for life. It is not produced by vaccination, so it separates natural exposure from vaccine-derived immunity. The IgM form of the core antibody points to recent infection; the total core antibody with a negative IgM suggests infection happened long ago.

Two further tests describe how active the virus is. The e antigen, HBeAg, indicates high levels of viral replication and higher infectiousness. The HBV DNA test, often called the viral load, counts the amount of viral genetic material in the blood. Together with ALT levels and assessment of scarring, these guide the specialist’s decision about whether antiviral treatment, which works by blocking the virus’s ability to copy itself, is appropriate. That decision, and any timing around it, sits with the treating clinician.

Age at infection shapes the outcome. WHO notes that around 90% of infants infected in the first year of life develop chronic infection, compared with fewer than 5% of otherwise healthy adults. Anyone with a positive HBsAg is also usually tested for hepatitis D, because coinfection changes the picture.

Hepatitis C testing: antibody first, then RNA

Hepatitis C follows a two-step logic that trips up a surprising number of people. The first test looks for antibodies. A negative antibody result, outside the early window period, means no infection. A positive result means the immune system has met the virus at some point, and nothing more.

That second point is the crux. WHO reports that roughly 30% of people who acquire hepatitis C, within a range of 15% to 45%, clear the virus on their own within six months without treatment. Those people keep a positive antibody for life, yet they have no virus in their blood. The only way to distinguish a cleared infection from an ongoing one is the second step: a hepatitis C RNA test, which detects the genetic material of the virus itself. The CDC recommends that laboratories run this automatically whenever the antibody is positive, a practice called reflex testing, so that a single blood draw answers both questions.

A positive RNA result confirms current infection and is the point at which specialist referral usually happens. Further tests may quantify the amount of virus and, in some settings, identify its genotype, meaning which strain of the virus is present. Modern antiviral medicines act directly on proteins the virus needs to replicate, and WHO describes typical treatment courses lasting 12 to 24 weeks, with the choice and duration determined by the prescribing clinician after assessing the liver.

The Mayo Clinic notes that because hepatitis C is so often silent, screening is recommended for all adults at least once rather than only for those with symptoms. WHO estimates that about 50 million people live with chronic hepatitis C worldwide. A great many of them would have normal liver enzymes on a routine panel, which is why the antibody test, not the ALT, is the tool that finds them.

When the cause isn't a virus: alcohol, medicines, autoimmune and inherited causes

A negative viral panel does not end the search; it redirects it. In many people with inflamed livers, the cause was never infectious, and the third tier of testing is designed to find it.

Alcohol is assessed largely through honest history, supported by patterns in the bloods: an AST that runs higher than ALT, a raised GGT (gamma-glutamyl transferase, an enzyme sensitive to alcohol and bile duct irritation) and enlarged red cells all lean in that direction. None is proof on its own.

Medicine-induced liver injury is diagnosed by timeline. The clinician lines up every prescription, over-the-counter product and herbal supplement against the date the enzymes rose. Paracetamol (acetaminophen) taken in excess, certain antibiotics, some anti-seizure medicines and a range of herbal and bodybuilding supplements are well-documented culprits according to MedlinePlus and the NHS. No blood test names the drug; stopping a suspected agent is a decision for the prescriber, never something to attempt alone.

Autoimmune hepatitis, in which the immune system attacks liver cells, is suggested by antinuclear antibodies, anti-smooth muscle antibodies and a raised total immunoglobulin G. It is more common in women and often needs a biopsy to confirm.

Inherited conditions have their own markers. Hereditary haemochromatosis, an iron-overload disorder, shows up as a high ferritin with a high transferrin saturation. Wilson’s disease, a rare copper-storage disorder that tends to appear in younger people, is screened with a serum caeruloplasmin and urinary copper. Alpha-1 antitrypsin deficiency is checked with a protein level and genetic typing.

Fat accumulation in the liver, now termed metabolic dysfunction-associated steatotic liver disease, is the most common non-viral cause in many countries and is usually recognized on ultrasound alongside features such as raised blood glucose and triglycerides. Other viruses such as Epstein-Barr, cytomegalovirus and hepatitis E round out the list when the picture is acute and the history fits.

What ultrasound and elastography add (and what they cannot show)

Imaging answers questions that blood cannot. Ultrasound uses high-frequency sound waves to build a picture of the liver, gallbladder and bile ducts. It involves no radiation, takes around 15 to 30 minutes, and is usually the first scan ordered.

What it shows well: the size and outline of the liver, whether the tissue looks brighter than normal in the way fat makes it look, whether the bile ducts are dilated behind a blockage, whether gallstones are present, and whether there are focal lumps that need further characterization. With a Doppler setting, it also shows the direction and speed of blood flow in the portal vein, which can change when the liver has become scarred and stiff. Fluid in the abdomen and an enlarged spleen, both signs of advanced disease, are easily seen.

What it cannot do: ultrasound does not detect viruses, does not measure inflammation and cannot tell hepatitis B from hepatitis C or from an autoimmune cause. An entirely normal ultrasound is common in early or mild hepatitis of any cause. It rules out structural problems; it does not rule out disease.

Elastography fills part of that gap. Using either a dedicated ultrasound-based device or a specialized MRI sequence, it measures how quickly a small vibration travels through the liver. Stiffer tissue transmits it faster, and stiffness correlates with fibrosis, the build-up of scar tissue. It is now widely used instead of biopsy to stage chronic hepatitis B and C. One caveat the treating team will weigh: active inflammation, recent eating and heart failure all raise stiffness readings, so a scan performed during a flare may overstate scarring, and repeating it once the enzymes settle is common.

CT and MRI are reserved for characterizing lumps or complex anatomy. Liver biopsy remains the reference standard when the diagnosis is genuinely uncertain, particularly for suspected autoimmune disease, and carries small risks of pain and bleeding that the team discusses beforehand.

Who is usually offered tests to find the cause of hepatitis, and who is asked to wait

Two groups are routinely investigated. The first is anyone whose liver enzymes are found to be raised, whether during a check-up, before starting a new medicine, or because of symptoms such as yellowing of the eyes, dark urine, pale stools, unusual tiredness or pain under the right ribs. The second is anyone with a clear exposure: a needle-stick injury, a sexual partner or household contact with hepatitis B or C, a history of injecting drugs, a transfusion before modern screening, or birth to a mother with hepatitis B.

Screening extends beyond these groups. The CDC recommends that every adult be tested for hepatitis C at least once, and for hepatitis B at least once, regardless of risk factors, and that everyone be tested for both during each pregnancy. WHO makes similar recommendations globally. The reasoning is simple: most chronic infection is silent, and a one-time blood test is the only reliable way to find it.

Some people are asked to wait, and that can feel like being brushed off. It usually reflects sound reasoning. A person tested within days of a possible exposure may have a negative panel simply because antibodies have not yet formed; the CDC’s window periods mean a repeat test weeks later is more informative than a full work-up now. A mildly raised ALT in someone who feels well, has recently had a viral illness or has just started exercising hard is often rechecked after several weeks before anything further is ordered, because a good proportion normalize on their own. Elastography is deferred until acute inflammation settles, for the reasons above.

Children follow the same blood-test pathway as adults, with the same viral markers and liver panel, though results are interpreted against age-specific ranges and the history focuses more on recent infections, medicines and family conditions. Anyone with signs of liver failure is never asked to wait; that pathway is described in the final section.

Comparison table: the main tests to find the cause of hepatitis at a glance

No single test does everything. The table below sets out what each of the main tests to find the cause of hepatitis measures, the question it answers, and where it falls short. Reading down the third column shows why clinicians order them in sequence rather than all at once.

Test	What it measures	Question it answers	Main limitation
Liver panel (ALT, AST, ALP, bilirubin, albumin)	Enzymes leaked from cells, bile flow, protein production	Is the liver inflamed, and is it a cell or bile-duct pattern?	Says nothing about the cause; can be normal in chronic infection
Prothrombin time / INR	Speed of blood clotting	Is liver function failing?	Also affected by vitamin K and blood thinners
Hepatitis panel (HAV IgM, HBsAg, anti-HBc IgM, anti-HCV)	Viral antigens and antibodies	Is hepatitis A, B or C present?	Window period after exposure; C antibody does not confirm current infection
HBV DNA / HCV RNA	Viral genetic material	Is the virus actively replicating, and how much?	Not ordered until antigen or antibody is positive
Autoimmune antibodies and IgG	Immune markers	Is the immune system attacking the liver?	Can be positive in other conditions; biopsy often needed
Iron and copper studies	Ferritin, transferrin saturation, caeruloplasmin	Is there inherited overload?	Ferritin rises with any inflammation
Ultrasound	Size, texture, ducts, blood flow	Is there a structural problem or fat?	Cannot detect viruses or grade inflammation
Elastography	Liver stiffness	How much scarring is there?	Overreads during active inflammation
Biopsy	Tissue under a microscope	What is the diagnosis when others disagree?	Invasive; small bleeding risk; samples a tiny area

The pattern to notice is complementarity. Blood tests identify causes; imaging identifies consequences. A specialist reading the whole set can usually name the cause, gauge the severity and estimate how long the process has been going on, which is the information that shapes every decision that follows.

What the following days and weeks usually look like

Most of the waiting in a hepatitis work-up is for results rather than for procedures. The liver panel and clotting test are typically reported within a day or two. Viral markers can take several days, and reflex RNA testing or specialist antibody panels sometimes a week or more, depending on the laboratory. Ultrasound is often arranged within a couple of weeks unless the clinical picture is urgent, in which case it happens the same day.

What happens next depends on which door the results open. If acute hepatitis A is confirmed, the NHS notes that the illness usually clears on its own within a few months and care centres on rest, fluids and avoiding alcohol and unnecessary medicines while the liver recovers; repeat enzymes track that recovery. Close contacts may be offered vaccination.

If hepatitis B surface antigen is positive, the crucial follow-up is a repeat test at six months, since persistence beyond that point defines chronic infection under WHO criteria. In the meantime, the team usually checks HBeAg, viral load, hepatitis D status and liver stiffness, and arranges for household and sexual contacts to be tested and vaccinated if they are not immune.

If hepatitis C RNA is positive, referral to a specialist follows, with staging of scarring by elastography and a discussion of antiviral treatment, whose course length WHO describes as typically 12 to 24 weeks. A repeat RNA test some months after treatment ends confirms whether the virus has been cleared.

If everything viral is negative, the pace slows a little. Autoimmune and metabolic tests are added, a medication review is completed, and enzymes are rechecked over four to twelve weeks to see whether they are climbing, stable or settling. Many people in this group are found to have fatty liver or a medicine-related rise that resolves once the trigger is identified. Throughout, the timeline is set by the treating team and adjusted to how the individual’s numbers behave.

What people often get wrong about hepatitis tests

The first and most consequential misunderstanding is that normal liver enzymes mean a healthy liver. Chronic hepatitis B and C frequently produce normal or only fluctuating ALT values, particularly in the early decades. WHO estimated that in 2022 only about 13% of people living with chronic hepatitis B had been diagnosed. Those people were not walking around with red numbers on their reports; they were walking around with no test at all.

The second is reading a positive hepatitis C antibody as a positive diagnosis. As described earlier, the antibody persists for life after a cleared infection. Without the RNA test, the result is unfinished.

The third is the mirror image for hepatitis B: seeing a positive surface antibody and assuming infection. That marker is protection, and in most adults it is the fingerprint of childhood vaccination.

Fourth, many people believe hepatitis is by definition viral or by definition contagious. Autoimmune, alcohol-related, medicine-related and fatty liver disease are all forms of hepatitis, and none passes from person to person.

Fifth, an ultrasound that comes back normal is often taken as an all-clear. Ultrasound looks at structure. It does not see viruses, immune activity or early scarring. A normal scan with abnormal bloods is a common and entirely expected combination.

Sixth, people sometimes stop a prescribed medicine the moment they suspect it is responsible for their liver results. Some medicines cause a harmless, temporary rise in enzymes; stopping others abruptly carries risks of its own. The medication review belongs to the prescriber.

Finally, there is the belief that a vaccine covers all types. Safe, effective vaccines exist for hepatitis A and B, and the hepatitis B vaccine indirectly prevents hepatitis D. There is no vaccine for hepatitis C, which is one reason one-time screening for every adult is recommended by the CDC.

Questions to ask your care team

A follow-up appointment about liver results can move quickly, and it helps to walk in with the questions written down. The aim is not to challenge the plan but to understand it well enough to follow it, and to leave knowing what the next result would change.

Start with the pattern. Ask which values were abnormal, whether the pattern points to the liver cells or the bile ducts, and how far outside the reference range they sit. Ask whether the clotting test was included, since that is the measure of function rather than injury.

Then ask about causes and timing.

• Which viral markers were checked, and were any results still pending or in a window period that would justify repeating them?
• If a hepatitis C antibody was positive, has an RNA test been done or arranged?
• If hepatitis B surface antigen was positive, when will it be repeated to determine whether the infection is chronic, and should household or sexual contacts be tested or vaccinated?
• Have my medicines and supplements been reviewed as a possible cause, and is there anything I should change only with your guidance?
• Are autoimmune, iron or copper tests planned, and what would prompt them?
• Do I need an ultrasound or elastography, and should it wait until the inflammation settles?
• What symptoms should make me call before the next appointment?

Close with practicalities: whether alcohol should be avoided while the cause is being investigated, whether a referral to a liver specialist is planned, and how results will be communicated. If a biopsy is being considered, ask what question it is expected to answer and what the alternatives are. A clear answer to that single question is often the best measure of whether the procedure is worth its small risks.

When to call your doctor

Most hepatitis work-ups proceed at an outpatient pace, and most people feel well throughout. A small number of situations change that, and the treating team would rather hear about them early than late.

Contact the clinic promptly, or use urgent care services, if the skin or whites of the eyes turn yellow or become noticeably more yellow than before; if urine turns dark while stools become pale or clay-coloured; if there is persistent vomiting and fluids cannot be kept down; if there is severe or worsening pain under the right ribs or across the upper abdomen; if a fever accompanies any of these; or if bruising appears easily or gums or nose bleed without an obvious reason. These signs can indicate that inflammation is progressing or that bile flow is blocked, and they usually prompt same-day blood tests.

Call emergency services or go to the nearest emergency department without delay if there is confusion, unusual drowsiness, difficulty staying awake or a change in personality, because these can signal the liver is failing to clear toxins from the blood; if there is vomiting of blood or passing of black, tarry stools; if the abdomen swells rapidly; or if a large amount of paracetamol (acetaminophen) or any other medicine has been taken in excess, even if there are no symptoms yet, since the treatment window is time-critical.

Anyone who is pregnant and develops symptoms of hepatitis should be seen urgently, as should infants and young children with jaundice beyond the newborn period, and anyone with a weakened immune system.

None of this is intended to alarm. The overwhelming majority of people whose raised enzymes lead to a hepatitis work-up never experience these signs. Knowing them simply means that if something changes, the response is quick, and the decision about what to do next rests, as it should, with the clinicians who know the full picture.

Frequently asked questions

What tests indicate hepatitis?

A liver panel showing raised ALT and AST indicates that liver cells are inflamed, which is the laboratory definition of hepatitis. Bilirubin, ALP, albumin and a clotting test describe how severe it is and whether bile flow is affected. Identifying the cause then needs a hepatitis panel for viruses A, B and C, plus autoimmune, iron and copper tests when those are negative. Ultrasound and elastography assess structure and scarring rather than diagnosing hepatitis itself.

How is hepatitis diagnosed if my liver tests are normal?

Chronic hepatitis B and C often produce normal or only intermittently raised enzymes, so diagnosis in those cases comes from the viral markers themselves: hepatitis B surface antigen and hepatitis C antibody followed by RNA. This is why the CDC recommends one-time screening of all adults regardless of liver test results. Elastography can also reveal scarring in someone whose enzymes look unremarkable, prompting a fuller search for the cause.

What are the 7 early signs of hepatitis?

There is no official list of seven, and most early hepatitis has no signs at all, which is why testing matters more than symptom-watching. When symptoms do occur, the NHS describes tiredness, loss of appetite, nausea, pain under the right ribs, dark urine, pale stools and yellowing of the skin or eyes. Any of these, particularly yellowing or dark urine, should be assessed by a clinician rather than interpreted at home.

Which organ is mostly affected by hepatitis?

The liver is the organ affected; the word hepatitis comes from the Greek for liver plus the suffix for inflammation. The liver filters toxins, produces clotting proteins and albumin, processes bilirubin and stores energy, so inflammation can show up as jaundice, easy bruising, fatigue or fluid retention. Some hepatitis viruses cause brief symptoms elsewhere, such as joint pain, but the damage that matters clinically happens in liver tissue.

Can you have hepatitis for 20 years and not know it?

Yes. Chronic hepatitis B and C are frequently silent for decades, with normal or fluctuating liver enzymes and no symptoms until significant scarring has developed. WHO estimated that in 2022 only around 13% of people living with chronic hepatitis B had been diagnosed. This long quiet phase is the central argument for one-time screening of all adults, which both the CDC and WHO recommend.

Do I need to fast before a hepatitis panel blood test?

Fasting is not usually required for the hepatitis panel or the standard liver panel, according to MedlinePlus, though the laboratory or clinician will say if other tests on the same sample need it. Elastography is different: recent eating can raise liver stiffness readings, so a few hours without food is commonly requested beforehand. Follow the specific instructions given with the appointment rather than assuming.

What does a positive hepatitis C antibody test mean?

A positive antibody means the immune system has encountered the hepatitis C virus at some point; it does not confirm current infection. WHO reports that about 30% of people clear the virus spontaneously within six months yet keep the antibody for life. An RNA test, which the CDC recommends laboratories run automatically after a positive antibody, is the result that determines whether the virus is still present.

Can an ultrasound show hepatitis?

Not directly. Ultrasound shows the size and texture of the liver, fat accumulation, dilated bile ducts, gallstones, lumps and blood flow, and it can be entirely normal in early or mild hepatitis of any cause. It cannot detect viruses or measure inflammation. Its role is to rule out structural problems and, through elastography, to estimate scarring. The diagnosis of hepatitis and its cause comes from blood tests.

How soon after exposure do hepatitis tests become positive?

It depends on the virus and the test. The CDC notes that hepatitis C RNA is detectable within one to two weeks of exposure, while the antibody usually appears after about eight to eleven weeks. WHO describes a hepatitis B incubation period of 30 to 180 days, with surface antigen typically detectable within the first one to two months. A negative result taken very early is often repeated later.

What is the difference between acute and chronic hepatitis?

Acute hepatitis lasts less than six months; chronic hepatitis persists beyond that, a threshold used by WHO and the NHS. Hepatitis A is always acute and resolves on its own. Hepatitis B becomes chronic in fewer than 5% of infected adults but around 90% of infected infants, according to WHO. Hepatitis C becomes chronic in the majority of adults who do not clear it spontaneously within the first six months.

References

• MedlinePlus: Hepatitis Panel
• MedlinePlus: Liver Function Tests
• CDC: Testing for Hepatitis C
• WHO: Hepatitis B Fact Sheet

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.