CONSENSUS REPORT: Group B Streptococci
This information was the outcome of the workshop breakout discussion. A complete copy of the 1997 Standards of Practice Workshop binder is available by contacting the Registrar of the Canadian College of Microbiologists.

1. COMMUNICATION:
1.1 To Screen or Not to Screen:
It was agreed by all that there was a wide range of players that needed to be involved in effective prevention of early onset sepsis due to Group B Streptococci (GBS). It was suggested that the most effective approach would be to obtain in-house data in terms of the method being used as well as published data on the value of the enrichment rectal/vaginal screening approach and then get together all of the people involved in the decision-making process such that these data could be discussed and a decision made whether GBS screening will be done or not. The issue was raised that there is often a small portion of the medical community that is unwilling to change their practice, regardless of the data presented to them. The issue of changing physician practice has been addressed in a recent article by Andrew Oxman et al (1). One of the recommendation is to use the "champion" approach. This involves getting a respected member of the medical community or the program director if the hospital is using a programmatic approach and have that individual be the person who liaises or interacts with the other physicians in the group.

1.2 Timing of Specimen Collection: The guidelines recommend GBS screening in weeks 35-37, but in many instances, obstetricians are screening patients at multiple different time points in their prenatal care. It was suggested that a pictorial guide indicating the appropriate specimen collection, which guidelines are being followed and reflecting the need to screen only in weeks 35-37 should be provided to appropriate clinics. Those physicians indicating concern about missing women who go into pre term labour, need only review the data indicating that premature labour is one of the risk factors that in and of itself would warrant intrapartum antibiotics. Since the purpose of GBS screening is only to identify those women whose neonates are at risk of early onset sepsis and should receive intrapartum antibiotics, screening in week 35-37 is appropriate and having "baseline" or earlier GBS screening is currently unnecessary. There is some indication that carriage of large amounts of GBS in the vagina of the pregnant mother, may be a predictor of spontaneous abortion or pre term labour. It was agreed that this was a separate issue from what is being addressed by current GBS screening recommendations and that although future GBS screening may change, at present the current guidelines should be followed.

1.3 Availability of Screening Results: Results of GBS screening must be available such that even if a women has prenatal care at one clinic, the data on her GBS screening is available at the site that she chooses to go to for delivery of her neonate. GBS screening is of little value if when a women goes into labour, the information is not available at the site she is admitted to for delivery.

2. ORDERING OF TEST REQUESTS: Cervical swabs are inappropriate for GBS screening, vaginal swabs are optimal. Due to the streamlining of diagnostic services, the laboratory can no longer support a wide range of testing when female genital swabs are not well identified. It is agreed that the onus is on the requesting physician to ensure that the appropriate information was put on the requisition and the appropriate sample is obtained. Computer systems may help if the test requests can be listed as a vag/rectal for GBS ensuring that the requester of the test is aware of the type of sample that should be collected. For paper requisitions, it would be easiest if there was a box to check off which indicated vag/rectal for GBS. However, it was noted that in Ontario, some of the order forms for the private laboratories require this information to be handwritten. It is important to target the physician who is ordering the test, but in addition, the individual writing up the order must also be aware of the appropriate test requests for swabs being submitted for GBS screening.

3. ALGORITHM FOR CLINICAL DECISION GUIDELINES: Again, it was reiterated that in practice the timing of screening is often variable and it is important that if a decision has been made by the Obs & Gyne Department to include GBS screening, that the appropriate utilization of the test be emphasized. This includes screening at week 35-37 and does not include screening prior to this time. It was felt by all in attendance that evaluating the method and timing of GBS screening as a quality indicator assessment would be an excellent part of a CQI program. This would involve assessing the method and week of gestation that screening was done and providing feedback of this in-house data to the Obstetricians along with appropriate data from the literature indicating the method and at what week in gestation that screening should be performed. This is particularly relevant as centralization of laboratory services continue to proceed and our ability to maintain an adequate communication with the generators of the test is made more difficult.

4.2 Self-Collection: Self-collection of a vaginal/rectal swab or having a health care worker take the specimen were both viewed as acceptable methods for GBS screening. If the patient prefers separate swabs, one for the vagina and one for the rectum, this is also acceptable. Upon receipt in the laboratory these swabs would be combined together in the enrichment broth and treated as one enrichment sample. It was also indicated that if patients are self collecting swabs, it is critical that there is a clear page for instructions for these individuals.

4.3 Enrichment/Selection Broth: The GBS enrichment broth using colistin and nalidixic acid (e.g. LIM) would likely provide less detrimental effect on GBS compared to the enrichment broth (e.g. SIM) that incorporates Gentamicin. This is because the MIC90 for GBS for Gentamicin is 32 ug/ml (2) very close to the amount used in the enrichment broth that contains Gentamicin (8 ug/ml). Although both enrichment broths are recommended by the CDC guidelines, awareness of the effect of gentamicin on GBS is important on making decisions about which enrichment broth to select. Because this is a broth media and it contains antibiotics, it is important to be aware that the inhibitory ability of the antibiotics will deteriorate with time if stored at room temperature. Optimal storage of such medium is frozen at -20oC. This lends itself very nicely to the laboratory as the media once prepared or received can be stored in a -20oC freezer and only those needed can be thawed out prior to inoculating with the swabs. If bedside inoculation into the enrichment broth is used, the Obs & Gyne clinic can store the broth frozen in a regular freezer and only take out those that are required for the days patients.

References:

1. Andrew D. Oxman et al. No Magic Bullets: A Systematic Reviews of 102 Trials of Interventions to Improve Professional Practice. Can Med Assoc J 1995; 153(10):1423-1431.

2. Lorian V.C. (Editor). Antibiotics in Laboratory Medicine 4th Edition 1996 page 990.

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Consensus Report: Vaginitis and Vaginosis
This information was the outcome of the workshop breakout discussion. A complete copy of the 1997 Standards of Practice Workshop binder is available by contacting the Registrar of the Canadian College of Microbiologists.

1. VAGINOSIS:
1.1 Prepubertal issues: <=13 years
Reason for collection is mandatory in order to process prepubertal samples.

SEXUAL ABUSE: process as for N. gonorrhoeae if a cervical sample is not available or possible.

VAGINOSIS REQUEST: There are no guidelines to diagnose vaginosis in this age group. A rejection report should be sent with the criteria This specimen is not suitable for the diagnosis of vaginosis in a prepubertal child.

1.2 Post menopausal Issues:

REPORT:

VAGINITIS: the presence or absence of yeast or Trichomonas

VAGINOSIS: scoring for bacterial vaginosis is inappropriate for this age range. In the post menopausal women without estrogen supplements, the vaginal flora scoring is uninterpretable. For post menopausal women on estrogen, there are no current guidelines for interpretation of vaginal flora scoring. For this specimen the score is -------.

1.3 The presence or absence of epithelial cells:

The absence of epithelial cells in a vaginal specimen sent for BV should be noted as insufficient specimen please repeat.

If transit time is excessive, (4-5 days) a recommendation should be made that a smear should accompany the specimen to preserve the morphology of cells.

1.4 Intermediate vaginosis score and report:

The comments as suggested by Ellen Jo Baron in the text from the binder should be used.

2. VAGINITIS
2.1 Culture for Trichomonas:
The consensus group reported that both in the private laboratory and in a tertiary care hospital, the incidence of Trichomonas from culture was less than 0.8 % and did not warrant the cost of culture.

The group indicated that the incidence of Trichomonas in the patient population should be assessed and culture initiated for high risk populations only. Cultures where appropriate, should be read on day 1 and day 3 only.

2.2 Use of DNA probes:

The group felt that there was not enough evidence to warrant the use of DNA probes for vaginitis or vaginosis at this time.

2.3 Relative # of yeast to report:

If only occasional yeast are seen, a report of normal flora should be issued. If there are >1 in every other field, a report of few, moderate or many yeast cells should be made.

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Consensus Report: Chlamydia/Gonorrhoeae
This information was the outcome of the workshop breakout discussion. A complete copy of the 1997 Standards of Practice Workshop binder is available by contacting the Registrar of the Canadian College of Microbiologists.

Dr. Max Chernesky
Issues that arose from the subject outlined in the text binder and presentation included:

1. Sexual abuse situations
2. What to do with results from amplified tests
3. Surveillance for Neisseria gonorrhoeae

1. SEXUAL ABUSE SITUATIONS: In sexual abuse situations, we recommend a traditional specimen to be collected for culture and a second specimen for an amplified test. Other less traditional specimens which may be of use would be vaginal, rectal or pharyngeal swabs. If possible, specimens from alleged abusers should also be submitted.

2. WHAT TO DO WITH RESULTS FROM AMPLIFIED TESTS: If amplified testing is performed with cultures and prevalence rates are observed to be higher than expected, we recommend that testing results should be discussed with physicians, confirm the positives with a second set of nucleic acid primers and treat with appropriate antibiotics.

3. SURVEILLANCE FOR NEISSERIA GONORRHOEAE: Since there appears to be an increasing number of laboratories replacing GC culturing with amplified nucleic acid tests, we recommend that within each province sentinel laboratories and clinics be designated for culturing. Federal STD funds should be used to determine the ability of molecular technology to identify resistance without growth of the organism (ie FRLP for chromosomal or plasmid resistance).

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Because of time limitations, "Presumptive diagnosis versus definitive" and "Quality Management" were not discussed.

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