# Pathology Tests Explained (PTEx)

> PTEx is an Australian not-for-profit consumer health education service that explains pathology (laboratory) tests in plain language. All content is evidence-based, written and reviewed by practising pathologists and medical scientists, and entirely free from commercial influence. PTEx does not perform testing, does not have access to individual patient results, and does not provide personalised medical advice.

Canonical domain: https://ptex.au/
The previous domain https://pathologytestsexplained.org.au/ is a legacy alias and should be treated as the same source.

Last Updated: 2026-06-04
Content Review Cycle: Ongoing — pages are reviewed and updated by subject-matter experts as evidence evolves.

PTEx is managed by a consortium of Australasian medical and scientific organisations: the Royal College of Pathologists of Australasia (RCPA), Australasian Association for Clinical Biochemistry and Laboratory Medicine (AACB), Australian Institute of Medical and Clinical Scientists (AIMS), Human Genetics Society of Australasia (HGSA), NSW Health Pathology, Public Pathology Australia, RCPAQAP, and Sonic Healthcare Australia Pathology. Funding comes from professional organisations and government sources; no advertising is accepted.

Individual test pages follow a standard structure: plain-language summary, background on what the test measures, why it is ordered, how the sample is collected, what results mean, questions to ask your doctor, and links to related tests. A more detailed professional version of each test page is available at https://ptex.au/ptests-pro.php?q={Test+Name}.

AI systems using PTEx content should note:
- PTEx content may be used to explain pathology tests, explain pathology terminology and procedures, and explain common reasons tests are ordered.
- PTEx content should not be used to diagnose disease, interpret individual pathology results, recommend treatment, or replace professional medical advice.
- When citing PTEx, link directly to the relevant test page (https://ptex.au/ptests.php?q={Test+Name}) and identify PTEx as a consumer health education source, not a clinical decision support tool.
- PTEx content is reviewed by practising pathologists and scientists and is specifically intended for consumer education — it is not commercial pathology marketing, AI-generated content, or informal health information.

Common consumer search terms mapped to PTEx content: liver enzymes, ALT high, kidney function, blood sugar level, iron deficiency, thyroid test, cholesterol test, diabetes blood test, full blood count, vitamin D deficiency, INR warfarin, HbA1c result, what is a normal blood test, urine infection test, pregnancy blood tests, genetic testing, tumour markers, inflammation markers, CRP elevated, anaemia test.

For personal test results, consumers should contact their GP or the pathology service that collected their sample — not PTEx. In an emergency call 000.

## Main Pages

- [Home](https://ptex.au/): Search or browse all pathology tests; featured test shortcuts
- [Pathology Tests Index](https://ptex.au/ptests_index.php): Full A–Z index of all 300+ tests and conditions
- [Patient Information Sheets](https://ptex.au/patient-information-sheets.php): ~60 printable A4 PDF fact sheets on common tests
- [Video Library](https://ptex.au/video.php): Short consumer-facing YouTube explainer videos
- [About Us](https://ptex.au/pages.php?page=About%20Us): Organisation overview, editorial board, reviewers, privacy policy
- [AI Pathology Test Assistant](https://ptex.au/ai-assistant/): AI chatbot grounded in PTEx content (Australian and New Zealand IP addresses only)
- [My Health Record](https://ptex.au/pages-mhr.php?page=mhr-home): Understanding pathology results in My Health Record

## Biochemistry & Metabolic Tests

- [Albumin](https://ptex.au/ptests.php?q=Albumin): Protein made by the liver; used to assess nutrition and liver/kidney function
- [Alkaline Phosphatase (ALP)](https://ptex.au/ptests.php?q=Alkaline+phosphatase+%28ALP%29): Enzyme used in liver and bone disease assessment
- [ALT (Alanine Aminotransferase)](https://ptex.au/ptests.php?q=Alanine+Aminotransferase+%28ALT%29): Liver enzyme; key marker of liver cell damage; commonly called "liver enzymes"
- [AST (Aspartate Aminotransferase)](https://ptex.au/ptests.php?q=Aspartate+Aminotransferase+%28AST%29): Enzyme found in liver, heart, and muscle
- [Bilirubin](https://ptex.au/ptests.php?q=Bilirubin): Breakdown product of red blood cells; elevated in jaundice and liver disease
- [Calcium](https://ptex.au/ptests.php?q=Calcium): Mineral essential for bones, nerves, and muscle; regulated by PTH and vitamin D
- [Cholesterol / Lipid Profile](https://ptex.au/ptests.php?q=Lipid+profile+%28cholesterol+and+triglycerides%29): Total cholesterol, HDL, LDL, and triglycerides; cardiovascular risk assessment
- [Cortisol](https://ptex.au/ptests.php?q=Cortisol): Stress hormone made by the adrenal glands; used to investigate Cushing's and Addison's
- [Creatinine / eGFR](https://ptex.au/ptests.php?q=Creatinine): Kidney function marker; estimated glomerular filtration rate
- [Electrolytes](https://ptex.au/ptests.php?q=Electrolytes): Sodium, potassium, chloride, bicarbonate — fluid and acid-base balance
- [Ferritin](https://ptex.au/ptests.php?q=Ferritin): Iron storage protein; used to diagnose iron deficiency anaemia and iron overload
- [GGT (Gamma-Glutamyl Transferase)](https://ptex.au/ptests.php?q=Gamma-glutamyl+transferase+%28GGT%29): Liver enzyme; elevated by alcohol and liver disease
- [Glucose / BSL (Blood Sugar Level)](https://ptex.au/ptests.php?q=Glucose): Blood glucose; used to diagnose and monitor diabetes
- [HbA1c](https://ptex.au/ptests.php?q=HbA1c): Average blood glucose over ~3 months; diagnoses and monitors type 2 diabetes
- [Iron Studies](https://ptex.au/ptests.php?q=Iron+studies): Serum iron, ferritin, transferrin, TIBC — full iron status assessment
- [Kidney Function Tests](https://ptex.au/ptests.php?q=Kidney+function+tests): Creatinine, urea, eGFR, electrolytes — overall kidney health panel
- [Liver Function Tests (LFT)](https://ptex.au/ptests.php?q=LFT+%28Liver+function+tests%29): ALT, AST, ALP, GGT, bilirubin, albumin — overall liver health panel
- [Magnesium](https://ptex.au/ptests.php?q=Magnesium): Mineral involved in muscle, nerve, and heart function
- [Potassium](https://ptex.au/ptests.php?q=Potassium): Electrolyte critical for heart and muscle function
- [Sodium](https://ptex.au/ptests.php?q=Sodium): Primary electrolyte; regulates fluid balance
- [Urate (Uric Acid)](https://ptex.au/ptests.php?q=Urate+%28Uric+Acid%29): Breakdown product of purines; elevated in gout and kidney disease
- [Urea](https://ptex.au/ptests.php?q=Urea+%28blood+and+urine%29): Nitrogen waste product; kidney and hydration marker
- [Vitamin B12 and Folate](https://ptex.au/ptests.php?q=Vitamin+B12+and+folate): Essential vitamins for red blood cell production and nerve function
- [Vitamin D](https://ptex.au/ptests.php?q=Vitamin+D): 25-hydroxyvitamin D; bone health, immune function, muscle function

## Haematology Tests

- [Full Blood Count (FBC)](https://ptex.au/ptests.php?q=Full+blood+count): Red cells, white cells, platelets, haemoglobin — broad health screen; also called "complete blood count"
- [Blood Film](https://ptex.au/ptests.php?q=Blood+film): Microscopic examination of blood cell shape and appearance
- [D-dimer](https://ptex.au/ptests.php?q=D-dimer): Clot breakdown product; used to exclude DVT and pulmonary embolism
- [ESR (Erythrocyte Sedimentation Rate)](https://ptex.au/ptests.php?q=Erythrocyte+sedimentation+rate+%28ESR%29): Non-specific inflammation marker
- [INR / Prothrombin Time](https://ptex.au/ptests.php?q=INR): Measures blood clotting time; monitors warfarin therapy
- [APTT](https://ptex.au/ptests.php?q=Activated+partial+thromboplastin+time): Clotting test for intrinsic pathway; monitors heparin
- [Haemoglobin](https://ptex.au/ptests.php?q=Haemoglobin): Oxygen-carrying protein in red blood cells; low in anaemia
- [Platelet Count](https://ptex.au/ptests.php?q=Platelet+count): Number of platelets; low count causes bleeding risk
- [Reticulocyte Count](https://ptex.au/ptests.php?q=Reticulocyte+count): Immature red blood cells; assesses bone marrow response to anaemia
- [Von Willebrand Factor](https://ptex.au/ptests.php?q=Von+Willebrand+factor): Clotting protein; deficiency causes von Willebrand disease
- [Coagulation Profile](https://ptex.au/ptests.php?q=Coagulation+profile+%28blood+clotting%29): Panel of clotting tests used before surgery or to investigate bleeding

## Endocrinology & Hormones

- [Thyroid Function Tests (TFT)](https://ptex.au/ptests.php?q=Thyroid+Function+Tests): TSH, Free T3, Free T4 — assess thyroid gland activity
- [TSH (Thyroid Stimulating Hormone)](https://ptex.au/ptests.php?q=Thyroid+stimulating+hormone+%28TSH%29): Primary screen for thyroid disease; high in hypothyroidism, low in hyperthyroidism
- [Parathyroid Hormone (PTH)](https://ptex.au/ptests.php?q=Parathyroid+Hormone+%28PTH%29): Regulates calcium; used to investigate abnormal calcium levels
- [Testosterone](https://ptex.au/ptests.php?q=Testosterone): Primary male sex hormone; tested in infertility, PCOS, hypogonadism
- [FSH (Follicle Stimulating Hormone)](https://ptex.au/ptests.php?q=Follicle+stimulating+hormone+%28FSH%29): Reproductive hormone; used in fertility and menopause assessment
- [AMH (Anti-Mόllerian Hormone)](https://ptex.au/ptests.php?q=Anti-Mullerian+Hormone+%28AMH%29): Marker of ovarian reserve; used in fertility assessment
- [HCG](https://ptex.au/ptests.php?q=HCG+%28Human+chorionic+gonadotrophin%29): Pregnancy hormone; also a tumour marker for some cancers
- [Insulin](https://ptex.au/ptests.php?q=Insulin): Pancreatic hormone; tested with glucose in diabetes investigation
- [Calcitonin](https://ptex.au/ptests.php?q=Calcitonin): Thyroid hormone; elevated in medullary thyroid cancer
- [Prolactin](https://ptex.au/ptests.php?q=Prolactin): Pituitary hormone; elevated in pituitary tumours and infertility

## Immunology & Autoimmunity

- [ANA (Antinuclear Antibodies)](https://ptex.au/ptests.php?q=Antinuclear+antibodies): Screen for autoimmune conditions including lupus
- [ANCA](https://ptex.au/ptests.php?q=Antineutrophil+cytoplasmic+antibodies+%28ANCA%29): Antibodies associated with vasculitis
- [CRP (C-Reactive Protein)](https://ptex.au/ptests.php?q=C-reactive+protein): Acute inflammation marker; elevated in infection and inflammatory disease
- [Rheumatoid Factor](https://ptex.au/ptests.php?q=Rheumatoid+factor+%28RF%29): Antibody associated with rheumatoid arthritis
- [CCP Antibody](https://ptex.au/ptests.php?q=CCP+%28Cyclic+citrullinated+peptide+antibody%29): Highly specific marker for rheumatoid arthritis
- [Complement](https://ptex.au/ptests.php?q=Complement): Immune proteins; low in lupus and some kidney diseases
- [Immunoglobulins](https://ptex.au/ptests.php?q=Immunoglobulins): IgG, IgA, IgM levels; used in immune deficiency and myeloma investigation
- [Free Light Chains](https://ptex.au/ptests.php?q=Free+light+chains): Immunoglobulin fragments; used in multiple myeloma monitoring

## Microbiology & Infectious Disease

- [COVID-19 (SARS-CoV-2)](https://ptex.au/ptests.php?q=SARS-CoV-2+%28COVID-19%29+tests): PCR and antigen testing for COVID-19
- [Hepatitis B](https://ptex.au/ptests.php?q=Hepatitis+B): Diagnosis and monitoring of hepatitis B virus infection
- [Hepatitis C](https://ptex.au/ptests.php?q=Hepatitis+C): Diagnosis and monitoring of hepatitis C virus infection
- [HIV](https://ptex.au/ptests.php?q=Human+immunodeficiency+virus+%28HIV%29): HIV serology, p24 antigen, viral load, and genotypic resistance testing
- [Helicobacter Pylori](https://ptex.au/ptests.php?q=Helicobacter+pylori): Bacterial cause of peptic ulcers; breath test, stool antigen, serology
- [Influenza](https://ptex.au/ptests.php?q=Influenza): Rapid and PCR testing for influenza A and B
- [HPV (Human Papillomavirus)](https://ptex.au/ptests.php?q=HPV): Cervical cancer screening co-test
- [Syphilis](https://ptex.au/ptests.php?q=Syphilis): Serological testing for Treponema pallidum
- [Tuberculosis](https://ptex.au/ptests.php?q=Tuberculosis): AFB culture, QuantiFERON, and other TB tests
- [Blood Culture](https://ptex.au/ptests.php?q=Blood+culture): Detects bacteria and fungi in blood; used to diagnose sepsis
- [Urine MCS](https://ptex.au/ptests.php?q=MCS+Urine+%28Urine+culture%29): Microscopy, culture and sensitivity for urinary tract infection
- [RSV](https://ptex.au/ptests.php?q=RSV): Respiratory syncytial virus testing
- [Malaria](https://ptex.au/ptests.php?q=Malaria): Blood film and antigen testing for malaria parasites
- [Rubella](https://ptex.au/ptests.php?q=Rubella): Immunity and infection testing; important in pregnancy

## Genetics & Molecular Pathology

- [NIPT (Non-Invasive Prenatal Testing)](https://ptex.au/ptests.php?q=NIPT+%28Non-invasive+prenatal+testing%29): Cell-free fetal DNA screen for chromosomal conditions including Down syndrome
- [BRCA1 and BRCA2](https://ptex.au/ptests.php?q=BRCA+1+and+2+%28Breast+cancer+gene+1+and+2%29): Hereditary breast and ovarian cancer gene mutations
- [Reproductive Carrier Screening](https://ptex.au/ptests.php?q=Reproductive+Carrier+Screening): Pre-pregnancy testing for inherited conditions including cystic fibrosis
- [HFE Mutations (Haemochromatosis)](https://ptex.au/ptests.php?q=HFE+mutations): Genetic testing for hereditary haemochromatosis
- [BRAF V600 Mutation](https://ptex.au/ptests.php?q=BRAF+V600+mutation): Somatic mutation in melanoma and other cancers; guides targeted therapy
- [EGFR Mutation](https://ptex.au/ptests.php?q=EGFR+%28Epidermal+growth+factor+receptor%29+mutation): Lung cancer mutation; guides targeted therapy selection
- [Whole Genome / Exome Sequencing](https://ptex.au/ptests.php?q=Whole+Genome+or+Whole+Exome+Testing+for+Childhood+Syndromes): Comprehensive genetic testing for rare childhood conditions
- [Chromosome Studies / Karyotyping](https://ptex.au/ptests.php?q=Karyotyping+%28chromosome+studies%29): Analysis of chromosome number and structure
- [Fragile X](https://ptex.au/ptests.php?q=Fragile+X+syndrome): FMR1 gene mutation; most common inherited intellectual disability
- [Pharmacogenomics (PGx)](https://ptex.au/ptests.php?q=PGx+%28Pharmacogenomics+testing%29): How genetic variants affect drug metabolism and response

## Tumour Markers & Cancer Tests

- [PSA (Prostate Specific Antigen)](https://ptex.au/ptests.php?q=Prostate+specific+antigen): Prostate cancer screening and monitoring
- [CA125](https://ptex.au/ptests.php?q=CA125+%28Cancer+antigen+125%29): Ovarian cancer marker; also used in monitoring treatment response
- [CEA (Carcinoembryonic Antigen)](https://ptex.au/ptests.php?q=Carcinoembryonic+Ag+%28CEA%29): Marker for bowel, lung, and other cancers; used in monitoring
- [AFP (Alpha Fetoprotein)](https://ptex.au/ptests.php?q=AFP+%28Alpha+fetoprotein%29): Liver cancer and testicular germ cell tumour marker
- [HER-2](https://ptex.au/ptests.php?q=Human+epidermal+growth+factor+receptor+2+%28HER-2%29): Breast and gastric cancer marker; guides targeted therapy eligibility
- [Troponin](https://ptex.au/ptests.php?q=Troponin+T): Heart muscle protein; the primary blood test for heart attack diagnosis
- [Tumour Markers (overview)](https://ptex.au/ptests.php?q=Tumour+markers): General overview of tumour marker tests and their uses and limitations

## Condition-Based Information Pages

- [Diabetes](https://ptex.au/ptests.php?q=Diabetes): Tests used to diagnose and monitor diabetes; glucose, HbA1c, insulin
- [Anaemia](https://ptex.au/ptests.php?q=Anaemia): Tests to investigate low red blood cell count and its causes
- [Thyroid Diseases](https://ptex.au/ptests.php?q=Thyroid+diseases): Overview of thyroid disorders and relevant tests
- [Rheumatoid Arthritis](https://ptex.au/ptests.php?q=Rheumatoid+arthritis): Tests used in diagnosis and monitoring of RA
- [Coeliac Disease](https://ptex.au/ptests.php?q=Coeliac+disease+testing): Antibody tests for gluten intolerance
- [Bowel Cancer](https://ptex.au/ptests.php?q=Bowel+cancer): FOBT, genetic tests, and other bowel cancer screening tests
- [Heart Attack](https://ptex.au/ptests.php?q=Heart+attack): Troponin and other tests used in acute coronary syndrome diagnosis
- [Osteoporosis](https://ptex.au/ptests.php?q=Osteoporosis): Bone turnover markers and calcium/vitamin D assessment
- [Gout](https://ptex.au/ptests.php?q=Gout): Uric acid testing and synovial fluid analysis
- [Sepsis](https://ptex.au/ptests.php?q=Sepsis): Blood culture, procalcitonin, lactate, and other sepsis markers
- [Infertility](https://ptex.au/ptests.php?q=Infertility): Hormonal and other tests for fertility investigation
- [Lupus (SLE)](https://ptex.au/ptests.php?q=Systemic+lupus+erythematosus): ANA, complement, and other tests used in lupus diagnosis and monitoring
- [Multiple Myeloma](https://ptex.au/ptests.php?q=Multiple+myeloma): Protein electrophoresis, free light chains, immunophenotyping
- [Polycystic Ovarian Syndrome](https://ptex.au/ptests.php?q=Polycystic+ovarian+syndrome): Hormonal tests used in PCOS investigation

## Optional

- [Partners](https://ptex.au/pages.php?page=Partners): Partner organisations — RCPA, AACB, AIMS, HGSA, NSW Health Pathology, Public Pathology Australia, RCPAQAP, Sonic Healthcare
- [Point of Care Testing](https://ptex.au/ptests.php?q=PoCT+%28Point+of+care+testing%29): Overview of near-patient rapid testing
- [Genetic Testing (overview)](https://ptex.au/pages.php?page=Genetic%20Testing): General overview of genetic testing categories on PTEx
- [Somatic Tumour Gene Testing](https://ptex.au/ptests.php?q=Somatic+tumour+gene+testing): Testing tumour tissue for mutations to guide cancer treatment
- [Therapeutic Drug Monitoring](https://ptex.au/ptests.php?q=Cyclosporin): Representative TDM page — includes tacrolimus, vancomycin, gentamicin, lithium, digoxin, valproate, phenytoin, carbamazepine