Sampling Technique for Isolation of Pharyngeal Gonorrhea
Sampling Technique for Isolation of Pharyngeal Gonorrhea
Over the 6-year study period, there were 106 364 visits by MSM to the clinic, from whom 32 855 pharyngeal specimens were obtained. The prevalence of pharyngeal gonorrhoea seen among MSM attending the clinic did not change significantly over the study period (figure 1, p for trend=0.5). Over the same period, there were 50 813 clinic visits by MSM seen by the 28 doctors and nurses who had continuous employment over the study period, with 23 632 pharyngeal specimens obtained by these clinicians. The detection rates for pharyngeal gonorrhoea for individual clinicians before and after the recommendations were made are shown in Table 1. The overall prevalence of pharyngeal gonorrhoea was 1.6% (134/8586) and 1.8% (264/15046) in the before and after periods respectively (p=0.34). Two clinicians had significant differences in their before and after detection rates—both had significantly lower detection rates in the after period. There was no significant difference in the overall detection rate for all clinicians combined before (1.6%) and after (1.8%) feedback was provided (p=0.17). Nor was there any significant correlation between detection rates by individual clinicians when these were compared for the before and after periods (r=0.19, p=0.33).
(Enlarge Image)
Figure 1.
The prevalence of pharyngeal gonorrhoea among men who have sex with men (MSM) attending the Melbourne Sexual Health Centre, June 2006–June 2012; p for trend=0.5. Arrow indicates when recommendations on sampling were made (May 2009). Prevalence is among all MSM attending the clinic, not just those seen by the clinicians included in the study.
Half (n=14) the clinicians in the study indicated that they had changed their pharyngeal swabbing technique since the recommendations were provided: all 14 reported swabbing a larger surface area, eight applied more pressure, 14 induced gag reflexes more frequently, 12 spent more time swabbing and 11 had changed the anatomical sites they swabbed.
Detection rates among clinicians, grouped according to whether they had changed specific aspects of their swabbing technique, are shown in Table 2. Compared with clinicians who did not change their swabbing technique, significantly higher detection rates were seen among clinicians who had changed their swabbing technique in response to the recommendations (2.1% vs 1.5%; p=0.004), swabbed a larger surface area (2.0% vs 1.5%; p=0.02), applied more swab pressure (2.5% vs 1.5%; p<0.001) and changed the anatomical sites which they swabbed (2.2% vs 1.5%; p=0.002).
While none of the increases in detection rates for individual clinicians was statistically significant, clinicians with higher detection rates in the period following the recommendations were, overall, more likely to have changed their swabbing technique. Sixty-nine percent (9/13) of the clinicians who had a subsequent increase in detection rates reported changing their technique, while only 33% (5/15) of clinicians whose detection rates had not increased reported a change in technique (p=0.058).
The median frequencies with which specific anatomical sites were swabbed before and after the recommendations are shown in Table 3. Prior to the recommendations, clinicians predominantly obtained samples from the tonsils, with few swabbing the oropharynx. Following the recommendations, the major change that occurred was an increase in swabbing of the oropharynx: the median frequency with which the oropharynx was swabbed increased from 0% to 80% of the time.
The median frequency with which clinicians reported inducing a gag reflex increased from 50% before the recommendations to 80% after. The median change in this frequency across clinicians as a group was 15%. Clinicians who had a change in the frequency with which they induced a gag reflex above the median (>15%) had significantly higher detection rates than clinicians who did not (p<0.001).
Results
Over the 6-year study period, there were 106 364 visits by MSM to the clinic, from whom 32 855 pharyngeal specimens were obtained. The prevalence of pharyngeal gonorrhoea seen among MSM attending the clinic did not change significantly over the study period (figure 1, p for trend=0.5). Over the same period, there were 50 813 clinic visits by MSM seen by the 28 doctors and nurses who had continuous employment over the study period, with 23 632 pharyngeal specimens obtained by these clinicians. The detection rates for pharyngeal gonorrhoea for individual clinicians before and after the recommendations were made are shown in Table 1. The overall prevalence of pharyngeal gonorrhoea was 1.6% (134/8586) and 1.8% (264/15046) in the before and after periods respectively (p=0.34). Two clinicians had significant differences in their before and after detection rates—both had significantly lower detection rates in the after period. There was no significant difference in the overall detection rate for all clinicians combined before (1.6%) and after (1.8%) feedback was provided (p=0.17). Nor was there any significant correlation between detection rates by individual clinicians when these were compared for the before and after periods (r=0.19, p=0.33).
(Enlarge Image)
Figure 1.
The prevalence of pharyngeal gonorrhoea among men who have sex with men (MSM) attending the Melbourne Sexual Health Centre, June 2006–June 2012; p for trend=0.5. Arrow indicates when recommendations on sampling were made (May 2009). Prevalence is among all MSM attending the clinic, not just those seen by the clinicians included in the study.
Half (n=14) the clinicians in the study indicated that they had changed their pharyngeal swabbing technique since the recommendations were provided: all 14 reported swabbing a larger surface area, eight applied more pressure, 14 induced gag reflexes more frequently, 12 spent more time swabbing and 11 had changed the anatomical sites they swabbed.
Detection rates among clinicians, grouped according to whether they had changed specific aspects of their swabbing technique, are shown in Table 2. Compared with clinicians who did not change their swabbing technique, significantly higher detection rates were seen among clinicians who had changed their swabbing technique in response to the recommendations (2.1% vs 1.5%; p=0.004), swabbed a larger surface area (2.0% vs 1.5%; p=0.02), applied more swab pressure (2.5% vs 1.5%; p<0.001) and changed the anatomical sites which they swabbed (2.2% vs 1.5%; p=0.002).
While none of the increases in detection rates for individual clinicians was statistically significant, clinicians with higher detection rates in the period following the recommendations were, overall, more likely to have changed their swabbing technique. Sixty-nine percent (9/13) of the clinicians who had a subsequent increase in detection rates reported changing their technique, while only 33% (5/15) of clinicians whose detection rates had not increased reported a change in technique (p=0.058).
The median frequencies with which specific anatomical sites were swabbed before and after the recommendations are shown in Table 3. Prior to the recommendations, clinicians predominantly obtained samples from the tonsils, with few swabbing the oropharynx. Following the recommendations, the major change that occurred was an increase in swabbing of the oropharynx: the median frequency with which the oropharynx was swabbed increased from 0% to 80% of the time.
The median frequency with which clinicians reported inducing a gag reflex increased from 50% before the recommendations to 80% after. The median change in this frequency across clinicians as a group was 15%. Clinicians who had a change in the frequency with which they induced a gag reflex above the median (>15%) had significantly higher detection rates than clinicians who did not (p<0.001).