1,25-dihydroxyvitamin D (calcitriol)
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Macrolide Resistance Test (Mgen)
259.00
This test detects genetic markers of macrolide resistance in Mycoplasma genitalium. It helps guide targeted antibiotic treatment and improve cure rates.
Turnaround time
Results available 1-2 weeks after arrival in lab. Doctor's report sent the day after results available (if required)
Biomarkers count
1
Same-Day Appointments
UKAS Accredited Labs
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Under 18? Patients under 18 can only be seen at GB Medlabs and Clinilabs, Monday to Friday only.
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Details about Macrolide Resistance Test (Mgen)
What is the Macrolide Resistance Test (Mycoplasma genitalium)?
The Macrolide Resistance Test (Mycoplasma genitalium) is a molecular test that identifies genetic mutations associated with resistance to macrolide antibiotics, such as azithromycin. These mutations prevent standard antibiotics from effectively clearing the infection.
Mycoplasma genitalium is a sexually transmitted bacterium that can cause persistent urethritis, cervicitis and pelvic inflammatory disease. Because resistance rates are high, resistance testing is now considered best practice to ensure appropriate treatment selection.
This test is usually performed alongside Mycoplasma genitalium PCR detection.
Why do I need a Macrolide Resistance Test?
You may need this test if Mycoplasma genitalium infection has been detected or is strongly suspected. Treating resistant strains with ineffective antibiotics can prolong symptoms, increase transmission risk and contribute to further resistance.
Resistance-guided therapy improves treatment success, reduces repeat infections and limits unnecessary antibiotic exposure.
Symptoms and scenarios where testing is recommended:
- Persistent urethritis or cervicitis
- Positive Mycoplasma genitalium PCR result
- Failure of standard antibiotic treatment
- Ongoing genital symptoms despite therapy
- Pelvic inflammatory disease investigation
- Recurrent sexually transmitted infections
- Sexual health screening with symptoms
- Antibiotic stewardship and targeted therapy
Benefits of the Macrolide Resistance Test
- Guides effective antibiotic choice
Ensures treatment matches resistance status. - Reduces treatment failure
Avoids ineffective macrolide therapy. - Supports antibiotic stewardship
Limits unnecessary antibiotic use. - Improves cure rates
Enables resistance-directed management. - Prevents prolonged symptoms
Supports faster symptom resolution. - Reduces reinfection risk
Improves infection clearance. - Clinically recommended approach
Aligned with modern STI management guidelines. - Molecular-level accuracy
Detects resistance genes directly.
Step-by-Step: How Testing Works
Choose your preferred testing method
Testing is performed on the same sample used for Mycoplasma genitalium detection.
Sample Collection and Analysis
- A urine or swab sample is collected as advised.
- The sample undergoes PCR analysis.
- Resistance-associated mutations are identified.
- Results are delivered securely online.
Access your report
Results guide immediate and appropriate antibiotic treatment decisions.
Your Results Explained
No Resistance Detected
No macrolide resistance mutations identified.
Macrolide antibiotics may be effective for treatment.
Resistance Detected
Macrolide resistance mutations identified.
Alternative antibiotics are required to achieve cure.
Indeterminate Result
Resistance status could not be determined.
Repeat testing or specialist advice may be recommended.
How It Works
Simple steps to get your results
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Choose your test online and book in seconds. Select your preferred clinic location or home visit option.
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Visit or Test at Home
Attend one of our UK or London clinics, arrange a home nurse visit, or use a finger-prick kit where available.
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Get Your Results
Your sample is analysed by accredited UK laboratories, with secure results delivered directly to you.
Take control of your health with London Blood Tests
WhatsApp UsHow to Prepare for Your Test
Follow these guidelines for accurate results
Sample Timing
Where possible, attend your blood test between 7am and 12pm. Please wait until any short-term illness or infection has fully resolved before testing. Avoid intense exercise for 24–48 hours beforehand, as this can affect certain markers.
Fasting & Hydration
Fasting is not always required, but some tests may recommend it. If fasting is advised, avoid food for 8–12 hours before your appointment and drink water only. Stay well hydrated, as this helps with sample collection and accuracy.
Medications & Supplements
Continue prescribed medications unless advised otherwise by your clinician. Avoid vitamin, mineral, or biotin supplements for at least 24–48 hours before your test, as these can interfere with results. If you are unsure about any medication or supplement, please let us know before your appointment.
Hormones & Menstrual Cycle
For hormone-related tests, timing within your menstrual cycle may be important. If relevant, follow any specific guidance provided on your test page.
If you have any questions or special circumstances, our team is happy to advise before your appointment.
Frequently Asked Questions
A sexually transmitted bacterial infection.
Often performed alongside detection testing.
No fasting is required.
No, it detects resistance, not presence alone.
Alternative antibiotic treatment is recommended.
It means macrolides won’t work, but alternatives exist.
Yes, applicable to all adults.
Yes, incomplete or incorrect therapy can contribute.
Higher risk of treatment failure and recurrence.
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