Abstract
Aims: Mycoplasma genitalium causes a common, sexually transmitted bacterial infection. This study assessed the detection of M. genitalium in stored urine samples to understand the impact of sample storage on M. genitalium detection. Methods: Aliquots of M. genitalium-positive urine (n = 20 patients) were stored at either room temperature (22°C) or 4°C, without a preservative. At weekly intervals, samples were tested using the commercial test ResistancePlus MG® (SpeeDx®, Australia). We report the analysis at 1 week, an acceptable collection-to-test turnaround time, with further analysis over 5 weeks to illustrate degradation trends. Results: After storing at 4°C, the proportion of specimens that remained positive for M. genitalium was 100% after 1 week and 95% after 4 weeks. Storage at 22°C led to more rapid decline in detection in the first 4 weeks, with 95% detected after 1 week and 85% at 2 weeks onwards. At 5 weeks, samples stored at both temperatures had an 85% M. genitalium detection rate, with increase in crossing points (Cq) of 0·72 (95% confidence interval (CI) 0·01–1·43; P-trend = 0·027) at 4°C, and 1·75 ((95% CI 0·79–2·71), P-trend <0·001) at 22°C. Conclusions: Urine samples stored without preservative, and unfrozen, retained high M. genitalium detection levels over the short term (up to 5 weeks). To minimize degradation, storing at 4°C is recommended. Significance and Impact of the Study: There is little known about the stability of clinical samples for M. genitalium detection. This study found that a high proportion (85–100%) of samples are still suitable for M. genitalium detection after storage for up to 5 weeks.
| Original language | English |
|---|---|
| Pages (from-to) | 1219-1223 |
| Number of pages | 5 |
| Journal | Journal of Applied Microbiology |
| Volume | 127 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - Oct 2019 |
Keywords
- degradation
- detection
- diagnosis
- molecular genetic
- PCR
Cite this
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The impact of sample storage on molecular-based detection of Mycoplasma genitalium. / Murray, G. L.; Su, J. P.; Birnie, J.; Danielewski, J.; Machalek, D. A.; Bradshaw, C. S.; Read, T. R.H.; Costa, A. M.; Garland, S. M.
In: Journal of Applied Microbiology, Vol. 127, No. 4, 10.2019, p. 1219-1223.Research output: Contribution to journal › Article › Research › peer-review
TY - JOUR
T1 - The impact of sample storage on molecular-based detection of Mycoplasma genitalium
AU - Murray, G. L.
AU - Su, J. P.
AU - Birnie, J.
AU - Danielewski, J.
AU - Machalek, D. A.
AU - Bradshaw, C. S.
AU - Read, T. R.H.
AU - Costa, A. M.
AU - Garland, S. M.
PY - 2019/10
Y1 - 2019/10
N2 - Aims: Mycoplasma genitalium causes a common, sexually transmitted bacterial infection. This study assessed the detection of M. genitalium in stored urine samples to understand the impact of sample storage on M. genitalium detection. Methods: Aliquots of M. genitalium-positive urine (n = 20 patients) were stored at either room temperature (22°C) or 4°C, without a preservative. At weekly intervals, samples were tested using the commercial test ResistancePlus MG® (SpeeDx®, Australia). We report the analysis at 1 week, an acceptable collection-to-test turnaround time, with further analysis over 5 weeks to illustrate degradation trends. Results: After storing at 4°C, the proportion of specimens that remained positive for M. genitalium was 100% after 1 week and 95% after 4 weeks. Storage at 22°C led to more rapid decline in detection in the first 4 weeks, with 95% detected after 1 week and 85% at 2 weeks onwards. At 5 weeks, samples stored at both temperatures had an 85% M. genitalium detection rate, with increase in crossing points (Cq) of 0·72 (95% confidence interval (CI) 0·01–1·43; P-trend = 0·027) at 4°C, and 1·75 ((95% CI 0·79–2·71), P-trend <0·001) at 22°C. Conclusions: Urine samples stored without preservative, and unfrozen, retained high M. genitalium detection levels over the short term (up to 5 weeks). To minimize degradation, storing at 4°C is recommended. Significance and Impact of the Study: There is little known about the stability of clinical samples for M. genitalium detection. This study found that a high proportion (85–100%) of samples are still suitable for M. genitalium detection after storage for up to 5 weeks.
AB - Aims: Mycoplasma genitalium causes a common, sexually transmitted bacterial infection. This study assessed the detection of M. genitalium in stored urine samples to understand the impact of sample storage on M. genitalium detection. Methods: Aliquots of M. genitalium-positive urine (n = 20 patients) were stored at either room temperature (22°C) or 4°C, without a preservative. At weekly intervals, samples were tested using the commercial test ResistancePlus MG® (SpeeDx®, Australia). We report the analysis at 1 week, an acceptable collection-to-test turnaround time, with further analysis over 5 weeks to illustrate degradation trends. Results: After storing at 4°C, the proportion of specimens that remained positive for M. genitalium was 100% after 1 week and 95% after 4 weeks. Storage at 22°C led to more rapid decline in detection in the first 4 weeks, with 95% detected after 1 week and 85% at 2 weeks onwards. At 5 weeks, samples stored at both temperatures had an 85% M. genitalium detection rate, with increase in crossing points (Cq) of 0·72 (95% confidence interval (CI) 0·01–1·43; P-trend = 0·027) at 4°C, and 1·75 ((95% CI 0·79–2·71), P-trend <0·001) at 22°C. Conclusions: Urine samples stored without preservative, and unfrozen, retained high M. genitalium detection levels over the short term (up to 5 weeks). To minimize degradation, storing at 4°C is recommended. Significance and Impact of the Study: There is little known about the stability of clinical samples for M. genitalium detection. This study found that a high proportion (85–100%) of samples are still suitable for M. genitalium detection after storage for up to 5 weeks.
KW - degradation
KW - detection
KW - diagnosis
KW - molecular genetic
KW - PCR
UR - http://www.scopus.com/inward/record.url?scp=85068606059&partnerID=8YFLogxK
U2 - 10.1111/jam.14359
DO - 10.1111/jam.14359
M3 - Article
VL - 127
SP - 1219
EP - 1223
JO - Journal of Applied Microbiology
JF - Journal of Applied Microbiology
SN - 1364-5072
IS - 4
ER -