What blood tests are used to diagnose haemochromatosis?

The key screening tests are serum iron, TIBC (total iron-binding capacity), transferrin saturation (calculated as iron ÷ TIBC × 100), and serum ferritin. A fasting transferrin saturation above 45% on two separate occasions is the main trigger for HFE genetic testing (C282Y and H63D mutations). Liver function tests (LFTs) are also important to assess for liver damage.

What is a dangerous ferritin level for haemochromatosis?

In haemochromatosis, the risk of significant organ damage rises when ferritin exceeds 1000 mcg/L. At this level, liver fibrosis and cirrhosis become more likely. Most Australian haematologists aim to keep ferritin below 50-100 mcg/L with regular venesection (therapeutic phlebotomy). Early diagnosis, when ferritin is still below 500 mcg/L, greatly improves long-term outcomes.

How common is haemochromatosis in Australia?

Hereditary haemochromatosis is very common in Australia, particularly in people of Celtic and Northern European descent. Approximately 1 in 200 Australians of Northern European ancestry carries two copies of the C282Y HFE gene mutation (homozygous C282Y), making it one of the most prevalent autosomal-recessive genetic conditions in the country. However, many carriers never develop clinical iron overload.

Is haemochromatosis genetic testing covered by Medicare?

HFE gene testing (MBS item 73318) is Medicare-rebatable in Australia when iron studies are abnormal (elevated transferrin saturation or ferritin) or when a first-degree relative has been diagnosed with hereditary haemochromatosis. Speak to your GP about eligibility — a referral to a haematologist or gastroenterologist may be needed to access this test.

What does transferrin saturation of 45% or above mean?

A fasting transferrin saturation at or above 45% is the recommended screening threshold for hereditary haemochromatosis in Australian clinical guidelines. This means your iron-carrying protein (transferrin) is heavily loaded with iron. When elevated on two fasting measurements, HFE genetic testing is recommended. Transferrin saturation can vary day-to-day and is best measured fasting to reduce false positives.

How is haemochromatosis treated in Australia?

Venesection (therapeutic phlebotomy — removing 500 mL of blood, roughly equivalent to donating blood) is the standard treatment. Initially this may be weekly or fortnightly until ferritin reaches the target range (usually below 50-100 mcg/L), then maintenance every 3-6 months. Many patients donate through the Red Cross Blood Service. Iron chelation therapy is only used when venesection is not possible. Treatment prevents organ damage and can extend life expectancy to near-normal.

Should family members be tested for haemochromatosis?

Yes. All first-degree relatives (parents, siblings, children) of a confirmed C282Y homozygous patient should be offered testing. This is especially important for siblings, who have a 25% chance of also being C282Y homozygous. Iron studies (transferrin saturation and ferritin) are the recommended initial screening tests. Early detection before iron overload occurs means venesection may never be needed, or minimal treatment suffices.

Iron Disorders

Haemochromatosis Blood Tests

Iron overload diagnosis in Australia — which tests to get, what the results mean, and the pathway from detection to treatment.

This page provides general educational information about hereditary haemochromatosis and the blood tests used to diagnose it. It is not a substitute for professional medical advice. Always discuss abnormal iron studies with your GP or a specialist.

The Quick Answer

Hereditary haemochromatosis is a genetic condition that causes the body to absorb and store too much iron from food. Over time, excess iron deposits in the liver, heart, joints, pancreas, and other organs, causing progressive damage. The good news: it is highly treatable when caught early, and regular blood donation (venesection) can prevent organ damage entirely.

Haemochromatosis is one of the most common genetic conditions in Australia, particularly among people of Celtic and Northern European ancestry. Approximately 1 in 200 Australians of this background carry two copies of the C282Y HFE mutation — the commonest genetic cause.

Key test: Transferrin saturation ≥ 45%

Ferritin reflects iron stores

HFE genetic test confirms cause

Why This Condition Is Often Missed

Haemochromatosis is frequently undiagnosed for years because its early symptoms — fatigue, joint aches, and a general feeling of being unwell — are non-specific and easily attributed to other causes. Many people are only diagnosed incidentally when a blood test ordered for another reason reveals elevated iron markers.

Women are often diagnosed later than men because menstruation and pregnancy provide natural mechanisms for iron loss, delaying the accumulation of dangerous iron stores by one to two decades. Postmenopausal women and women who have had hysterectomies are at similar risk to men.

Importantly, not all people who carry the C282Y mutation will develop clinical iron overload. Penetrance is incomplete — many C282Y homozygotes never develop significant problems. This is why management decisions are based on iron studies (ferritin, transferrin saturation) rather than genotype alone.

The Blood Tests — What Each One Shows

Haemochromatosis is diagnosed through a combination of iron studies, genetic testing, and liver function assessment. Transferrin saturation is the most important initial screening test.

Serum Iron

Normal range: 10–30 µmol/L

Haemochromatosis: Often > 30 µmol/L

Measures iron circulating in blood at the time of the test. Elevated in active iron overload but can vary significantly meal to meal — best measured fasting.

TIBC (Total Iron-Binding Capacity)

Normal range: 45–80 µmol/L

Haemochromatosis: Often < 45 µmol/L (low or low-normal)

Reflects the capacity of transferrin to carry more iron. When iron stores are high, TIBC decreases because transferrin is already heavily loaded.

Transferrin Saturation

Normal range: 20–45% (fasting)

Haemochromatosis: > 45% (key screening threshold)

Calculated as Serum Iron ÷ TIBC × 100. This is the MOST IMPORTANT haemochromatosis screening test. A fasting value ≥ 45% on two occasions warrants genetic testing.

Serum Ferritin

Normal range: Males: 30–400 µg/L; Females: 15–200 µg/L

Haemochromatosis: Often > 300 µg/L (males), > 200 µg/L (females); severe: > 1000 µg/L

Reflects total body iron stores. Can be falsely elevated by inflammation, liver disease, metabolic syndrome, and alcohol — so clinical context is essential.

HFE Genetic Testing (C282Y, H63D)

Normal range: No mutations (wild type)

Haemochromatosis: C282Y homozygous (most common), C282Y/H63D compound heterozygous

Confirms the genetic cause. C282Y homozygosity (two copies) accounts for ~85% of clinical haemochromatosis in Australia. H63D homozygosity rarely causes significant iron overload alone.

Liver Function Tests (LFTs)

Normal range: ALT < 35 U/L (F), < 45 U/L (M); AST < 35 U/L

Haemochromatosis: Elevated ALT/AST indicate liver involvement

Iron deposits preferentially in hepatocytes, causing hepatitis-like inflammation that precedes fibrosis and cirrhosis. Elevated LFTs are a sign treatment is urgently needed.

Blood Glucose / HbA1c

Normal range: Fasting glucose < 5.5 mmol/L; HbA1c < 41 mmol/mol

Haemochromatosis: Elevated if iron has damaged the pancreas

Iron deposits in pancreatic beta cells cause "bronze diabetes" — a late complication of untreated haemochromatosis. Screening is recommended once ferritin exceeds 1000 µg/L.

Always fast before iron studies. Eating a meal high in iron or taking iron supplements before the blood test can artificially raise transferrin saturation by 10-20%, leading to false positives. Request a morning fasting appointment and avoid iron supplements for 24 hours beforehand.

Interpreting Your Results — What Different Patterns Mean

Elevated transferrin saturation + elevated ferritin

This is the classic pattern of iron overload. If repeated fasting and confirmed, HFE genetic testing is the next step. Even if the gene result is negative, secondary causes of iron overload (liver disease, dysmetabolic iron overload syndrome, repeated transfusions) must be considered.

High ferritin but normal transferrin saturation

High ferritin with normal transferrin saturation is more likely an acute phase reaction— ferritin rises in inflammation, infection, metabolic syndrome, fatty liver disease, and heavy alcohol use. This pattern does NOT typically indicate haemochromatosis. Your GP will look for and treat the underlying inflammatory cause.

Elevated transferrin saturation + normal ferritin

This pattern suggests early iron loading before significant stores have accumulated. It may represent early haemochromatosis (particularly in young women) or a dietary iron excess. HFE genetic testing is still warranted. These patients often have the best long-term outcomes because they are caught before organ damage occurs.

C282Y heterozygote (one copy) — carrier

Approximately 1 in 8-10 Australians of Northern European ancestry carry one C282Y mutation. Carriers rarely develop significant iron overload on their own. If a carrier has elevated ferritin or transferrin saturation, other concurrent causes (alcohol, metabolic syndrome, H63D mutation) should be investigated. Most carriers need reassurance and no treatment.

Red Flags — When to Act Urgently

Haemochromatosis is a slowly progressive condition, but some findings should prompt prompt action rather than watchful waiting:

Ferritin > 1000 µg/L

At this level, liver biopsy or MRI is often recommended to assess for fibrosis or cirrhosis. Urgent venesection programme should begin promptly.

Elevated liver enzymes (ALT/AST)

Suggests iron is already damaging liver cells. If combined with high ferritin and transferrin saturation, refer to gastroenterology or hepatology urgently.

Symptoms of organ damage

Joint pain (especially in the 2nd and 3rd knuckles), fatigue, sexual dysfunction, skin bronzing, or abdominal pain in a person with elevated iron studies — seek review promptly.

Diabetes plus elevated iron

"Bronze diabetes" is a late, largely preventable complication of haemochromatosis. Unexplained diabetes in someone with iron overload needs urgent iron workup.

Cardiac arrhythmias plus elevated ferritin

Iron deposits in cardiac muscle can cause heart failure and rhythm problems. Cardiac involvement is a medical emergency.

Family member diagnosed with C282Y haemochromatosis

You have a 25% chance (if a sibling) or 50% risk of being a carrier. Request iron studies from your GP — do not wait for symptoms.

The GP Pathway — From Suspicious Result to Treatment

Understanding the typical Australian clinical pathway helps you know what to expect at each step:

Fasting iron studies (screening)

Your GP orders serum iron, TIBC, transferrin saturation, and ferritin. Tests should be done fasting (nothing to eat for 8-12 hours) to get an accurate transferrin saturation. A single elevated result should be repeated on a separate occasion before proceeding.

Confirm elevated transferrin saturation twice

A fasting transferrin saturation ≥ 45% on two occasions is the threshold for the next step. A single elevated reading can be due to timing (eating iron-rich food), supplements, or acute hepatitis — always confirm.

HFE genetic testing

A simple blood test for the C282Y and H63D mutations in the HFE gene. Medicare-rebatable when iron studies are abnormal (MBS item 73318). Results clarify the genetic subtype and risk of clinical iron overload.

Liver function tests and assessment

LFTs (ALT, AST, GGT, bilirubin) assess whether the liver has been damaged by iron deposition. If LFTs are elevated and ferritin > 1000 µg/L, liver biopsy or MRI liver iron quantification may be recommended.

Referral and treatment planning

Most GPs refer to a haematologist or gastroenterologist for management planning. Venesection frequency (typically weekly or fortnightly initially) is determined by ferritin level and general health.

Ongoing monitoring

Ferritin and transferrin saturation are checked regularly during the treatment phase. Once the target is reached (ferritin < 50-100 µg/L), maintenance venesection (3-6 monthly) continues for life. FBE is checked before each venesection to ensure haemoglobin is adequate.

Family screening

All first-degree relatives should be offered iron studies and, if appropriate, HFE genetic testing. Siblings have the highest risk (25% chance of C282Y homozygosity). Early detection before iron loading occurs is the goal.

Treatment — Venesection (Therapeutic Phlebotomy)

How venesection works

Each venesection removes approximately 500 mL of blood (equivalent to a blood donation), which contains around 200-250 mg of iron. The body responds by mobilising stored iron to make new red blood cells, steadily drawing down the iron burden. Most patients start with weekly or fortnightly sessions. When ferritin reaches the target range (typically 50-100 µg/L), maintenance venesection every 3-6 months continues for life to prevent re-accumulation.

Donating to the Red Cross Blood Service

Many haemochromatosis patients are eligible to donate their removed blood through the Australian Red Cross Blood Service, meaning treatment is free and the blood benefits others. Eligibility criteria apply and are assessed by the Blood Service. Your haematologist or GP can advise on whether this pathway is suitable for you.

Diet and lifestyle

Dietary changes are a secondary measure and will not replace venesection. However, avoiding iron supplements and vitamin C supplements (which enhance iron absorption), reducing red meat intake, avoiding alcohol (which worsens liver damage), and drinking tea or coffee with meals (which mildly inhibit iron absorption) can modestly slow iron re-accumulation between venesection sessions.

Prognosis with treatment

When haemochromatosis is diagnosed and treated before cirrhosis or diabetes develops, life expectancy is normal. Even with established liver fibrosis (non-cirrhotic), regular venesection can prevent progression. Arthropathy (joint damage) is the most common irreversible complication — it may not improve significantly with treatment but usually does not worsen once iron is controlled.

Good news: Haemochromatosis is one of the few genetic conditions where early diagnosis and simple, low-cost treatment can completely prevent all major complications. If you have Celtic or Northern European heritage and unexplained fatigue, joint pain, or elevated ferritin, ask your GP about iron studies.

Family Screening — Who Else Should Be Tested?

Haemochromatosis is autosomal-recessive, meaning both parents must contribute a mutation for a child to be affected. Once one person in a family is diagnosed, targeted testing of first-degree relatives is highly recommended:

Siblings

25% chance of C282Y homozygosity

Iron studies + HFE genetic testing

Children (adult)

At least carrier; affected if partner is also C282Y+

Iron studies; genetic testing if iron studies abnormal

Parents

Both are obligate C282Y carriers at minimum

Iron studies recommended, especially if over 50

Cascade screening: If a sibling is found to be C282Y homozygous, their children should also be tested once they reach adulthood (18+). HFE genetic testing for family screening purposes may be Medicare-rebatable — ask your GP.