Macrolide Resistance Test (Mgen)
Private Macrolide Resistance Test Mgen in London for £259, detecting resistance mutations with specialist results expected in around 1–2 weeks.
Turnaround time
1-2 weeks
Biomarkers count
1
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Overview of the Macrolide Resistance Test (Mgen)
The Macrolide Resistance Test (Mgen) is a specialist molecular test designed to detect genetic mutations associated with macrolide antibiotic resistance in Mycoplasma genitalium.
The test contains 1 biomarker: Macrolide Resistance Test (Mgen).
Mycoplasma genitalium, commonly abbreviated to Mgen, is a sexually transmitted bacterium that can infect the urethra, cervix and other exposed sites.
It can cause urethritis, cervicitis and pelvic inflammatory disease, although many infections are asymptomatic.
Mycoplasma genitalium is particularly important because antibiotic resistance is common.
Historically, macrolides such as Azithromycin were frequently used to treat the infection.
However, genetic mutations within bacterial ribosomal targets can prevent macrolide antibiotics from working effectively.
Resistance testing identifies these mutations using molecular methodology.
The result can therefore help clinicians select an antibiotic strategy rather than treating blindly with a macrolide that is unlikely to work.
This approach supports both treatment success and antimicrobial stewardship by reducing unnecessary exposure to ineffective antibiotics.
The Macrolide Resistance Test does not replace the diagnostic test for Mycoplasma genitalium itself.
A person normally needs evidence that Mgen is present, usually from a Mycoplasma genitalium PCR test, before resistance information becomes clinically useful.
A resistance result also does not mean that every possible antibiotic will or will not work.
It specifically provides information about the molecular markers included in the assay, principally those associated with macrolide resistance.
Treatment should therefore be prescribed according to current sexual-health guidance and the complete resistance and clinical picture.
What Does the Macrolide Resistance Test (Mgen) Test Check?
This test measures 1 biomarker.
Macrolide Resistance Test (Mgen)
Detects genetic mutations in Mycoplasma genitalium associated with resistance to macrolide antibiotics, supporting resistance-guided treatment selection.
Who May Benefit From the Macrolide Resistance Test (Mgen) Test?
Resistance testing is most useful when Mycoplasma genitalium has already been detected or there is a specific clinical reason to investigate treatment failure.
People with a positive Mycoplasma genitalium PCR result - Resistance information can help guide appropriate antibiotic treatment.
People whose Mgen infection has persisted after macrolide treatment - Resistance is one important explanation for treatment failure.
People with recurrent urethritis and confirmed Mgen - Molecular resistance testing can contribute to treatment planning.
Women with persistent cervicitis and confirmed Mgen - Resistance-guided management may improve the likelihood of bacterial clearance.
People with ongoing symptoms despite previous Azithromycin treatment - Macrolide-resistant Mgen should be considered when the organism remains detectable.
People with repeated positive Mgen PCR tests - Resistance assessment can provide important information when infection has not cleared.
People undergoing sexual-health management where resistance-guided therapy is available - Modern management increasingly incorporates resistance information.
People specifically advised to obtain Mgen macrolide resistance testing - The test should normally be interpreted by a clinician experienced in STI treatment.
How to Prepare
Do not start additional antibiotics independently before obtaining appropriate clinical advice.
Incorrect or repeated antibiotic exposure can promote further resistance and make subsequent Mgen treatment more difficult.
Symptoms and Reasons to Consider the Macrolide Resistance Test (Mgen) Test
Macrolide resistance itself does not produce different symptoms from susceptible Mycoplasma genitalium. The key clue is often persistent infection or symptoms despite treatment.
Persistent burning during urination after treatment - Ongoing urethritis can occur if Mgen has not been eradicated.
Persistent urethral discharge - Continued symptoms after therapy can justify repeat infection and resistance assessment.
Persistent abnormal vaginal or cervical discharge - Mgen can contribute to cervicitis, although many other conditions can produce discharge.
Bleeding after sex with confirmed Mgen - Cervical inflammation can sometimes cause contact bleeding.
Persistent pelvic discomfort with confirmed infection - Mgen has been associated with pelvic inflammatory disease in women.
Symptoms that returned after an apparently completed antibiotic course - Recurrence can reflect reinfection, treatment failure or persistent infection.
A repeat positive Mgen PCR after treatment - Continued molecular detection can prompt resistance-guided clinical review.
A sexual partner with confirmed treatment-resistant Mgen - Partner management may require specialist sexual-health advice.
No symptoms but confirmed Mgen requiring treatment selection - Asymptomatic infection can still require management according to the clinical setting.
These symptoms are not specific to Mycoplasma genitalium or macrolide resistance.
Severe pelvic pain, fever, pregnancy with significant pelvic symptoms or acute testicular pain requires prompt clinical assessment rather than relying only on resistance testing.
How to Book Your Macrolide Resistance Test (Mgen) Test
The test requires an appropriate molecular specimen and is usually performed in the context of confirmed Mgen infection.
Choose the Macrolide Resistance Test (Mgen)
Select the specialist resistance assay after confirming that this is the correct investigation for your Mgen result.
Select your sample collection option
Arrange the appropriate urine or site-specific PCR specimen according to the laboratory requirements.
Attend your appointment
The relevant sample is collected, and previous antibiotic and Mgen PCR information should be provided.
Laboratory analysis
Molecular testing is performed for genetic mutations associated with macrolide resistance.
Receive your results securely
Your authorised resistance report is delivered securely for use by the clinician selecting treatment.
When Will I Receive My Results?
The current London Blood Tests turnaround for the Macrolide Resistance Test (Mgen) is approximately 1–2 weeks after the appropriate specimen reaches the laboratory.
This is a specialist molecular resistance assay and takes longer than the standard Mycoplasma genitalium PCR used simply to detect whether the organism is present.
The laboratory must analyse resistance-associated genetic targets and complete its specialist quality-control and authorisation procedures before the report can be released.
The turnaround begins from laboratory receipt rather than from the day the specimen is collected.
An indeterminate result, insufficient bacterial DNA or an unsuitable specimen can occasionally require repeat analysis or a new sample, extending the overall timeline.
Understanding Your Results
A no macrolide resistance detected result means that the resistance-associated mutations targeted by the assay were not identified.
This can indicate that macrolide susceptibility is more likely, but treatment should still be prescribed according to current clinical guidance.
A macrolide resistance detected result means that one or more genetic mutations associated with reduced macrolide effectiveness were identified.
In this situation, treatment with a macrolide such as Azithromycin may have a substantially increased risk of failure.
An alternative resistance-guided treatment strategy may therefore be required.
An indeterminate result means that the laboratory could not establish resistance status reliably.
This can occur when the amount of bacterial genetic material is too low or another technical limitation affects analysis.
Resistance testing should be interpreted alongside the Mgen detection result, previous antibiotics, symptoms and likelihood of reinfection.
A resistant result does not mean that infection is untreatable.
Why Book With London Blood Tests?
Private Mgen resistance testing - Access specialist Mycoplasma genitalium resistance analysis privately.
Guides antibiotic selection - Resistance information can reduce the likelihood of using an ineffective macrolide.
Supports antimicrobial stewardship - Targeted treatment helps reduce unnecessary antibiotic exposure.
Relevant after treatment failure - Resistance testing can provide important information when Mgen remains detectable.
Molecular methodology - Resistance-associated mutations are detected directly.
Suitable alongside Mgen PCR - Detection and resistance testing answer complementary clinical questions.
Secure reporting - Receive your authorised resistance result confidentially.
Clear pricing - The Macrolide Resistance Test (Mgen) costs £259.
Private Macrolide Resistance Test (Mgen) in London
London Blood Tests provides private Macrolide Resistance Test (Mgen) testing for people requiring specialist molecular assessment of Mycoplasma genitalium antibiotic resistance.
The test costs £259 and measures one biomarker: Macrolide Resistance Test (Mgen).
Results are expected approximately 1–2 weeks after laboratory receipt.
The test is principally used to guide treatment after Mgen has been detected rather than as a standalone screening test for infection.