Lab tests
STI test report explainer
A sexual health screen is usually several separate tests on one page, each with its own vocabulary: detected or not detected for swab and urine tests, reactive or non-reactive for blood tests, and ratios such as 1:8 for syphilis. Add your report below to see the tests separated and each term explained.
Explain your STI test report
- 1. Add itDrop a PDF, take a photo or paste the text.
- 2. Check itPersonal details are removed on your device. You approve what is sent.
- 3. Read itSummary, table of results, terms and questions to ask.
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What you get
- Each infection tested for listed on its own row, with the sample it was tested on.
- Abbreviations such as NAAT, PCR, RPR, VDRL, TPHA and EIA written out.
- Titers explained as the dilution steps they record.
- Questions to ask the sexual health clinic or doctor who sent the test.
Terms you may see on an STI report
- NAAT or PCRA test that looks for the genetic material of an organism in urine or on a swab
- Chlamydia trachomatis and Neisseria gonorrhoeaeThe laboratory names of the organisms behind chlamydia and gonorrhea
- Detected and not detectedWhether the NAAT found that genetic material in the sample
- Sample siteWhere the sample came from, such as urine, throat, rectal or vaginal swab, with a separate result for each
- Treponemal tests (TPHA, TPPA, EIA, FTA-ABS)Syphilis blood tests that look for antibodies to the syphilis organism itself
- Non-treponemal tests (RPR, VDRL)Syphilis blood tests that look for a different kind of antibody and are reported with a titer (also spelled titre)
- Equivocal, inhibited or invalidThe test did not give a clear answer on this sample
What this tool cannot tell you
Syphilis results in particular are read as a combination of tests and compared with any earlier results, so no single line stands by itself. A report also does not show when the sample was taken relative to any exposure, or what treatment a person has had in the past, and both change how a clinician reads it. MedicDecode explains the test names and result words. It does not say whether you have an infection, whether it is new or old, or what should happen next for you or a partner; a sexual health clinician does that.
Common questions
What does a titer such as 1:8 mean?
The laboratory dilutes the sample step by step and records the last dilution at which the test still reacts. 1:8 means it still reacted when diluted eight-fold. What a particular titer means for a person is a question for the clinician, who compares it with previous results.
Why are there two or three different syphilis tests on my report?
Laboratories commonly run one type of syphilis test first and then add a second type, and sometimes a third, to the same sample. The two families of test look for different antibodies, so they sit on separate lines and can carry different result words. The explanation shows which family each line belongs to.
The same test appears several times with different sites. Is that a mistake?
No. A NAAT is run separately on each sample, so a report can list urine, throat and rectal results one after another for the same organism. Each line refers only to the sample named beside it.
Words you may see on this report
Tap a word for its plain-English meaning, an example line and what it does not mean.
- ALT (Alanine Aminotransferase)
ALT is an enzyme found mainly in the liver; when liver cells are irritated or damaged, more ALT leaks into the blood.
- AST (Aspartate Aminotransferase)
AST is an enzyme found in the liver, muscles, heart and other tissues; raised levels can signal stress or damage in one of these.
- Bilirubin
Bilirubin is a yellow substance made when old red blood cells break down; the liver processes it so it can leave the body.
- Creatinine
Creatinine is a waste product from normal muscle activity that the kidneys filter out, so its blood level helps show how well the kidneys work.
- CRP (C-Reactive Protein)
CRP is a protein made by the liver that rises quickly when there is inflammation or infection in the body.
- Culture and Sensitivity
A culture and sensitivity test grows germs from a sample to identify them, then checks which antibiotics can stop them.
- eGFR (Estimated Glomerular Filtration Rate)
eGFR is an estimate of how well your kidneys filter waste from your blood, calculated from a creatinine blood test plus details like age.
- Electrolytes
Electrolytes are minerals in the blood, such as sodium, potassium and chloride, that carry an electric charge and help the body work.
- ESR (Erythrocyte Sedimentation Rate)
ESR measures how fast red blood cells sink in a tube of blood over an hour; a faster rate can be a general sign of inflammation.
- Fasting Sample
A fasting sample is blood taken after you have had nothing to eat or drink except water for a set number of hours.
- Ferritin
Ferritin is a protein that stores iron; its blood level gives a good idea of how much iron the body has in reserve.
- HbA1c
HbA1c shows your average blood sugar over roughly the past two to three months by measuring how much sugar is attached to red blood cells.