Bacterial vaginosis laboratory findings: Difference between revisions

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==Overview==
==Overview==
 
Bacterial vaginosis can be diagnosed by the use of clinical criteria ([[Bacterial vaginosis Amsel criteria|Amsel’s Diagnostic Criteria]]) or Gram stain. A Gram stain is considered the gold standard laboratory method for diagnosing bacteria vaginosis.<ref name=CDC_MMWR-2015>Center for Disease Control and prevention. Mortality and morbidity weekly reports. Sexually transmitted disease treatment guideline. (2015)  https://www.cdc.gov/std/tg2015/tg-2015-print.pdf Accessed on October 20, 2016</ref>
==Laboratory Findings==
==Laboratory Findings==
In clinical practice, the diagnosis of bacterial vaginosis is based on the presence of at least three [[Amsel criteria bacterial vaginosis|Amsel criteria]].
In clinical practice, the diagnosis of bacterial vaginosis is based on the presence of at least three [[Amsel criteria bacterial vaginosis|Amsel criteria]] on laboratory studies.<ref name=CDC_MMWR-2015>Center for Disease Control and prevention. Mortality and morbidity weekly reports. Sexually transmitted disease treatment guideline. (2015)  https://www.cdc.gov/std/tg2015/tg-2015-print.pdf Accessed on October 20, 2016</ref>
Usually vginal swabs following [[Speculum (medical)|speculum]] examination will be tested for:
Vaginal swabs following [[Speculum (medical)|speculum]] examination will be tested for:
*Whiff test: A small amount of an alkali is added to a [[microscope slide]] that has been swabbed with the discharge—a 'fishy' odour is a positive result for bacterial vaginosis.
*Whiff test: A small amount of an alkali is added to a [[microscope slide]] that has been swabbed with the discharge—a "fishy" odor is a positive result for bacterial vaginosis.
*Loss of [[acidity]]: A swab of the discharge is put onto [[litmus paper]] to check the acidity. A positive result for bacterial vaginosis would be a pH>4.5 (normally slightly acidic with a [[pH]] of 3.8–4.2).
*Loss of [[acidity]]: A swab of the discharge is put onto [[litmus paper]] to check the acidity. A positive result for bacterial vaginosis would be a pH>4.5 (normally slightly acidic with a [[pH]] of 3.8–4.2).
*Clue cells: [[epithelial]] cells coated with bacteria (under microscopic examination of the discharge)
*Clue cells: [[epithelial]] cells coated with bacteria (under microscopic examination of the discharge)
In research studies, the use of Nugent or Hay/Ison criteria to evaluate a Gram-stained smear of vaginal discharge is the diagnostic standard.
In research studies, the use of Nugent or Hay/Ison criteria to evaluate a Gram-stained smear of vaginal discharge is the diagnostic standard.


===Gram Satin===
===Gram Stain===
Gold standard for diagnosis of bacterial vaginosis is [[Garm stain]] vaginal discharge.<ref name="pmid1706728">{{cite journal| author=Nugent RP, Krohn MA, Hillier SL| title=Reliability of diagnosing bacterial vaginosis is improved by a standardized method of gram stain interpretation. | journal=J Clin Microbiol | year= 1991 | volume= 29 | issue= 2 | pages= 297-301 | pmid=1706728 | doi= | pmc=269757 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=1706728  }} </ref>
A Gram stain is considered the gold standard laboratory method for diagnosing bacteria vaginosis. It is used to determine the relative concentration of [[lactobacilli]] ([[Gram-positive|Gram-positive rods]]), [[Gram-negative]] and Gram-variable rods and cocci ([[Gardnerella vaginalis]], [[Prevotella]], [[Porphyromonas]], and peptostreptococci), and curved Gram- negative rods (Mobiluncus) which are characteristic of bacterial vaginosis.Gram staining is usually reserved for research studies and can be used with the Hay/Ison criteria or the Nugent criteria.<ref name=CDC_MMWR-2015>Center for Disease Control and prevention. Mortality and morbidity weekly reports. Sexually transmitted disease treatment guideline. (2015)  https://www.cdc.gov/std/tg2015/tg-2015-print.pdf Accessed on October 20, 2016</ref><ref name="pmid1706728">{{cite journal| author=Nugent RP, Krohn MA, Hillier SL| title=Reliability of diagnosing bacterial vaginosis is improved by a standardized method of gram stain interpretation. | journal=J Clin Microbiol | year= 1991 | volume= 29 | issue= 2 | pages= 297-301 | pmid=1706728 | doi= | pmc=269757 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=1706728  }} </ref>
===Cytology===
The Papanicolaou smear is not reliable for diagnosis of bacterial vaginosis.<ref name="pmid10819823">{{cite journal| author=Greene JF, Kuehl TJ, Allen SR| title=The papanicolaou smear: inadequate screening test for bacterial vaginosis during pregnancy. | journal=Am J Obstet Gynecol | year= 2000 | volume= 182 | issue= 5 | pages= 1048-9 | pmid=10819823 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=10819823  }} </ref>
===Culture===
Vaginal culture has no role in diagnosis of bacterial vaginosis.
===Electrolyte and Biomarker Studies===
Vaginal swabs following [[Speculum (medical)|speculum]] examination will be tested for:
*Whiff test: A small amount of an alkali is added to a [[microscope slide]] that has been swabbed with the discharge—a 'fishy' odour is a positive result for bacterial vaginosis.
*Loss of [[acidity]]: A swab of the discharge is put onto [[litmus paper]] to check the acidity. A positive result for bacterial vaginosis would be a pH>4.5 (normally slightly acidic with a [[pH]] of 3.8–4.2).
*Clue cells: [[epithelial]] cells coated with bacteria (under microscopic examination of the discharge)


===Diagnostic Criteria===
====Hay/Ison Criteria====
====Amsel Criteria====
The Hay/Ison criteria are defined as follows: <ref name="GCH2002">{{cite journal | author=Guideline Clearing House | title=2002 national guideline for the management of bacterial vaginosis | http://www.guideline.gov/summary/summary.aspx?ss=15&doc_id=3032&nbr=2258 }}</ref><ref name = HayIson>{{Citation | last1 = Ison | first1 = CA | last2 = Hay | first2 = PE | year = 2002 | title = Validation of a simplified grading of Gram stained vaginal smears for use in genitourinary medicine clinics | journal = Sex Transm Infect | volume = 78 | pages = 413–415}}</ref>
{| style="border: 0px; font-size: 90%; margin: 3px;" align=center
! style="background: #4479BA; width: 175px;" | {{fontcolor|#FFF|Grading}}
! style="background: #4479BA; width: 400px;" | {{fontcolor|#FFF|Definition}}
|-
| style="padding: 5px 5px; background: #DCDCDC;" |Grade 0


In clinical practice bacterial vaginosis (BV) is diagnosed using the Amsel criteria:<ref name = Amsel>{{Citation | last1 = Amsel | first1 = R| last2 = Totten | first2 = PA | last3 = Spiegel | first3 = CA | last4 = Chen | first4 = KC | last5 = Eschenbach | first5 = D | last6 = Holmes| first6 = KK | year = 1983 | title = Nonspecific vaginitis. Diagnostic criteria and microbial and epidemiologic associations | journal = Am J Med | volume = 74 | pages = 14–22}}</ref>
| style="padding: 5px 5px; background: #F5F5F5;" | No bacteria present
|-
| style="padding: 5px 5px; background: #DCDCDC;" | Grade 1


# Thin, white, yellow, homogeneous discharge
| style="padding: 5px 5px; background: #F5F5F5;" | [[Lactobacillus]] morphotypes predominate
# [[Clue cells]] on [[microscopy]]  
|-
# [[pH]] of vaginal fluid >4.5
| style="padding: 5px 5px; background: #DCDCDC;" | Garde 2
# Release of a fishy odor on adding [[alkali]]—10% [[potassium hydroxide]] (KOH) solution.


At least three of the four criteria should be present for a confirmed diagnosis.<ref name="GCH2002">{{cite journal | author=Guideline Clearing House | title=2002 national guideline for the management of bacterial vaginosis | http://www.guideline.gov/summary/summary.aspx?ss=15&doc_id=3032&nbr=2258 }}</ref>
| style="padding: 5px 5px; background: #F5F5F5;" |  Mixed flora with (some [[lactobacilli]], [[gardnerella]],or mobiluncus morphotypes present)
|-
| style="padding: 5px 5px; background: #DCDCDC;" | Garde 3
 
| style="padding: 5px 5px; background: #F5F5F5;" | Predominantly [[gardnerella]] and/or mobiluncus morphotypes (few or absent lactobacilli)
|-
| style="padding: 5px 5px; background: #DCDCDC;" | Garde 4


====Hay/Ison Criteria====
| style="padding: 5px 5px; background: #F5F5F5;" | Gram-positive cocci predominate
An alternative is to use a Gram stained vaginal smear, with the Hay/Ison<ref name = HayIson>{{Citation | last1 = Ison | first1 = CA | last2 = Hay | first2 = PE | year = 2002 | title = Validation of a simplified grading of Gram stained vaginal smears for use in genitourinary medicine clinics | journal = Sex Transm Infect | volume = 78 | pages = 413–415}}</ref> criteria or the Nugent<ref name="Nugent1991">{{cite journal |author=Nugent, R. P., M. A. Krohn, and S. L. Hillier | title=Reliability of diagnosing bacterial vaginosis is improved by a standardized method of Gram stain interpretation | journal=J. Clin. Microbiol | year=1991 | volume=29 | pages=297&ndash;301 }}</ref> criteria. The Hay/Ison criteria are defined as follows: <ref name="GCH2002">{{cite journal | author=Guideline Clearing House | title=2002 national guideline for the management of bacterial vaginosis | http://www.guideline.gov/summary/summary.aspx?ss=15&doc_id=3032&nbr=2258 }}</ref>
|}
* Grade 1 (Normal): [[Lactobacillus]] morphotypes predominate.
* Grade 2 (Intermediate): Mixed flora with some Lactobacilli present, but Gardnerella or Mobiluncus morphotypes also present.
* Grade 3 (Bacterial Vaginosis): Predominantly Gardnerella and/or Mobiluncus morphotypes. Few or absent Lactobacilli. (Hay et al., 1994)


What this technique loses in interobserver reliability, it makes up in ease and speed of use.
*Grade 3 is diagnostic


====Nugent Criteria====
====Nugent Criteria====
The standard for research are the Nugent<ref name="Nugent1991">next</ref> Criteria. In this scale a score of 0-10 is generated from combining three other scores. It is time consuming and requires trained staff but is has high [[Inter-observer reliability|interobserver reliability]]:
The standard for research are the Nugent Criteria.<ref name="Nugent1991">{{cite journal |author=Nugent, R. P., M. A. Krohn, and S. L. Hillier | title=Reliability of diagnosing bacterial vaginosis is improved by a standardized method of Gram stain interpretation | journal=J. Clin. Microbiol | year=1991 | volume=29 | pages=297&ndash;301 }}</ref>
* 0–3 is considered negative for BV
* 4–6 is considered intermediate
* 7+ is considered indicative of BV.
At least 10–20 high power (1000× oil immersion) fields are counted and an average determined.
 


{| style="border: 0px; font-size: 90%; margin: 3px;" align=center
{| style="border: 0px; font-size: 90%; margin: 3px;" align=center
|+
|+'''Average''' per high powered (1000× oil immersion) field. View multiple fields
! style="background: #4479BA; width: 175px;" | {{fontcolor|#FFF|Score}}
! style="background: #4479BA; width: 175px;" | {{fontcolor|#FFF|Score}}
! style="background: #4479BA; width: 400px;" | {{fontcolor|#FFF|0}}
! style="background: #4479BA; width: 400px;" | {{fontcolor|#FFF|0}}
Line 62: Line 57:
! style="background: #4479BA; width: 400px;" | {{fontcolor|#FFF|4}}
! style="background: #4479BA; width: 400px;" | {{fontcolor|#FFF|4}}
|-
|-
| style="padding: 5px 5px; background: #DCDCDC;" |  
| style="padding: 5px 5px; background: #DCDCDC;" |[[Lactobacillus]] morphotypes
 
| style="padding: 5px 5px; background: #F5F5F5;" |>30
 
| style="padding: 5px 5px; background: #F5F5F5;" | 15-30


| style="padding: 5px 5px; background: #F5F5F5;" |
| style="padding: 5px 5px; background: #F5F5F5;" | <14


| style="padding: 5px 5px; background: #F5F5F5;" |  
| style="padding: 5px 5px; background: #F5F5F5;" | <1 (this is an average)


| style="padding: 5px 5px; background: #F5F5F5;" |  
| style="padding: 5px 5px; background: #F5F5F5;" | 0
|-
|-
| style="padding: 5px 5px; background: #DCDCDC;" | '''Olecranon bursitis'''<ref name="pmid8894865">{{cite journal| author=Stell IM| title=Septic and non-septic olecranon bursitis in the accident and emergency department--an approach to management. | journal=J Accid Emerg Med | year= 1996 | volume= 13 | issue= 5 | pages= 351-3 | pmid=8894865 | doi= | pmc=1342774 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8894865  }} </ref><ref name="pmid21075998">{{cite journal| author=Lockman L| title=Treating nonseptic olecranon bursitis: a 3-step technique. | journal=Can Fam Physician | year= 2010 | volume= 56 | issue= 11 | pages= 1157 | pmid=21075998 | doi= | pmc=2980436 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21075998  }} </ref>
| style="padding: 5px 5px; background: #DCDCDC;" |[[Gardnerella]]/[[Bacteroides]] morphotypes
| style="padding: 5px 5px; background: #F5F5F5;" |
 
*[[Abrasion]] or [[contusion]] of skin (in a case of trauma)
| style="padding: 5px 5px; background: #F5F5F5;" | 0
*[[Swelling]], at the posterior elbow
 
*Goose egg appearance over the olecranon process
| style="padding: 5px 5px; background: #F5F5F5;" | <1 (this is an average)
*[[Tenderness]] for palpation at the affected site
 
*Systemic inflammatory processes
| style="padding: 5px 5px; background: #F5F5F5;" | 1-4
**[[Fever]]
 
**[[Rheumatoid nodules]]
| style="padding: 5px 5px; background: #F5F5F5;" | 5-30
| style="padding: 5px 5px; background: #F5F5F5;" |  


| style="padding: 5px 5px; background: #F5F5F5;" | >30
|-
|-
| style="padding: 5px 5px; background: #DCDCDC;" | '''Trochanteric bursitis'''<ref name="pmid17880718">{{cite journal| author=Brinks A, van Rijn RM, Bohnen AM, Slee GL, Verhaar JA, Koes BW et al.| title=Effect of corticosteroid injection for trochanter pain syndrome: design of a randomised clinical trial in general practice. | journal=BMC Musculoskelet Disord | year= 2007 | volume= 8 | issue=  | pages= 95 | pmid=17880718 | doi=10.1186/1471-2474-8-95 | pmc=2045096 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=17880718  }} </ref><ref name="pmid4055877">{{cite journal| author=Karpinski MR, Piggott H| title=Greater trochanteric pain syndrome. A report of 15 cases. | journal=J Bone Joint Surg Br | year= 1985 | volume= 67 | issue= 5 | pages= 762-3 | pmid=4055877 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=4055877  }} </ref>
| style="padding: 5px 5px; background: #DCDCDC;" |Curved Gram variable rods
| style="padding: 5px 5px; background: #F5F5F5;" |
 
*[[Tenderness]] at lateral hip, aggravated by active and passive external rotation and abduction
| style="padding: 5px 5px; background: #F5F5F5;" | 0
*Lateral hip pain on direct palpation
*Weakness of the hip-abductors
| style="padding: 5px 5px; background: #F5F5F5;" |  
*Ober's Test (reduced [[range of motion]] was significant)
*Resistance test  (pain and tenderness with resisting at external rotation)
|-
| style="padding: 5px 5px; background: #DCDCDC;" | '''Prepatellar bursitis'''<ref name=Bursitis-four-types> Aaron, Daniel L., et al. "Four common types of bursitis: diagnosis and management." Journal of the American Academy of Orthopaedic Surgeons 19.6 (2011): 359-367.</ref><ref name=Prepatellar-Bursitis> Huang, Yu-Chih, and Wen-Lin Yeh. "Endoscopic treatment of prepatellar bursitis." International orthopaedics 35.3 (2011): 355-358.</ref>
| style="padding: 5px 5px; background: #F5F5F5;" |
*[[Erythema]] at the affected site (knee)
*Ususally very large swelling over the knee
*[[Tenderness]] aggravated by bending and stretching the knee
*Reduced active [[range of motion]] (ROM)
| style="padding: 5px 5px; background: #F5F5F5;" |
|-
| style="padding: 5px 5px; background: #DCDCDC;" | '''Retrocalcaneal bursitis'''<ref name=Harrison-rheumatology> Fauci, Anthony S., and Carol Langford. Harrison's rheumatology. McGraw Hill Professional, 2010.</ref><ref name=Achilles-tendon> Lyman, Jeffrey, Paul S. Weinhold, and Louis C. Almekinders. "Strain behavior of the distal Achilles tendon implications for insertional Achilles tendinopathy." The American Journal of Sports Medicine 32.2 (2004): 457-461.</ref>
| style="padding: 5px 5px; background: #F5F5F5;" |
*[[Swelling]] at the back of heel
*[[Tenderness]] at the back of heel
*Painful ankle [[dorsiflexion]]
| style="padding: 5px 5px; background: #F5F5F5;" |
|}


| style="padding: 5px 5px; background: #F5F5F5;" | <5


| style="padding: 5px 5px; background: #F5F5F5;" | >5


| style="padding: 5px 5px; background: #F5F5F5;" |


{| class="wikitable"
| style="padding: 5px 5px; background: #F5F5F5;" |  
|  
Lactobacillus morphotypes — '''average''' per high powered (1000× oil immersion) field. View multiple fields.
||
[[Gardnerella]] / [[Bacteroides]] morphotypes — '''average''' per high powered (1000× oil immersion) field. View multiple fields.
  ||
Curved Gram variable rods — '''average''' per high powered (1000× oil immersion) field. View multiple fields (note that this factor is less important — scores of only 0–2 are possible)
|-
|
* Score 0 for >30
* Score 1 for 15–30
* Score 2 for 14
* Score 3 for <1 (this is an average, so results can be >0, yet <1)
* Score 4 for 0
||
* Score 0 for 0
* Score 1 for <1 (this is an average, so results can be >0, yet <1)
* Score 2 for 1–4
* Score 3 for 5–30
* Score 4 for >30
||
* Score 0 for 0
* Score 1 for <5
* Score 2 for 5+
|}
|}


A recent study <ref name="pmid17078859">{{cite journal |author=Gazi H, Degerli K, Kurt O, ''et al'' |title=Use of DNA hybridization test for diagnosing bacterial vaginosis in women with symptoms suggestive of infection |journal=APMIS |volume=114 |issue=11 |pages=784–7 |year=2006|pmid=17078859 |doi=10.1111/j.1600-0463.2006.apm_485.x}}</ref> compared the gram stain using the Nugent criteria and the DNA hybridization test Affirm VPIII in diagnosing BV. The Affirm VPIII test detected Gardnerella in 107 (93.0%) of 115 vaginal specimens positive for BV diagnosed by gram stain. The Affirm VPIII test has a [[sensitivity (tests)|sensitivity]] of 87.7% and [[specificity (tests)|specificity]] of 96% and may be used for the rapid diagnosis of BV in symptomatic women.
In this scale a score of 0-10 is generated from combining three other scores. It is time consuming and requires trained staff but is has high [[Inter-observer reliability|interobserver reliability]]:
* 0–3 is considered negative for bacterial vaginosis
* 4–6 is considered intermediate
* 7+ is considered indicative of bacterial vaginosis
 
===Cytology===
The Papanicolaou smear is not reliable for diagnosis of bacterial vaginosis.<ref name="pmid10819823">{{cite journal| author=Greene JF, Kuehl TJ, Allen SR| title=The papanicolaou smear: inadequate screening test for bacterial vaginosis during pregnancy. | journal=Am J Obstet Gynecol | year= 2000 | volume= 182 | issue= 5 | pages= 1048-9 | pmid=10819823 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=10819823  }} </ref>
===Culture===
Vaginal culture has no role in diagnosis of bacterial vaginosis. <ref name=CDC_MMWR-2015>Center for Disease Control and prevention. Mortality and morbidity weekly reports. Sexually transmitted disease treatment guideline. (2015) https://www.cdc.gov/std/tg2015/tg-2015-print.pdf Accessed on October 20, 2016</ref><ref name="pmid27428605">{{cite journal| author=Stockdale CK| title=A Positive Culture Result for Gardnerella Is Not Diagnostic of Bacterial Vaginosis. | journal=J Low Genit Tract Dis | year= 2016 | volume= 20 | issue= 4 | pages= 281-2 | pmid=27428605 | doi=10.1097/LGT.0000000000000237 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=27428605  }} </ref>


==References==
==References==
{{reflist|2}}
{{reflist|2}}


 
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Latest revision as of 20:34, 29 July 2020

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Overview

Bacterial vaginosis can be diagnosed by the use of clinical criteria (Amsel’s Diagnostic Criteria) or Gram stain. A Gram stain is considered the gold standard laboratory method for diagnosing bacteria vaginosis.[1]

Laboratory Findings

In clinical practice, the diagnosis of bacterial vaginosis is based on the presence of at least three Amsel criteria on laboratory studies.[1] Vaginal swabs following speculum examination will be tested for:

  • Whiff test: A small amount of an alkali is added to a microscope slide that has been swabbed with the discharge—a "fishy" odor is a positive result for bacterial vaginosis.
  • Loss of acidity: A swab of the discharge is put onto litmus paper to check the acidity. A positive result for bacterial vaginosis would be a pH>4.5 (normally slightly acidic with a pH of 3.8–4.2).
  • Clue cells: epithelial cells coated with bacteria (under microscopic examination of the discharge)

In research studies, the use of Nugent or Hay/Ison criteria to evaluate a Gram-stained smear of vaginal discharge is the diagnostic standard.

Gram Stain

A Gram stain is considered the gold standard laboratory method for diagnosing bacteria vaginosis. It is used to determine the relative concentration of lactobacilli (Gram-positive rods), Gram-negative and Gram-variable rods and cocci (Gardnerella vaginalis, Prevotella, Porphyromonas, and peptostreptococci), and curved Gram- negative rods (Mobiluncus) which are characteristic of bacterial vaginosis.Gram staining is usually reserved for research studies and can be used with the Hay/Ison criteria or the Nugent criteria.[1][2]

Hay/Ison Criteria

The Hay/Ison criteria are defined as follows: [3][4]

Grading Definition
Grade 0 No bacteria present
Grade 1 Lactobacillus morphotypes predominate
Garde 2 Mixed flora with (some lactobacilli, gardnerella,or mobiluncus morphotypes present)
Garde 3 Predominantly gardnerella and/or mobiluncus morphotypes (few or absent lactobacilli)
Garde 4 Gram-positive cocci predominate
  • Grade 3 is diagnostic

Nugent Criteria

The standard for research are the Nugent Criteria.[5]

Average per high powered (1000× oil immersion) field. View multiple fields
Score 0 1 2 3 4
Lactobacillus morphotypes >30 15-30 <14 <1 (this is an average) 0
Gardnerella/Bacteroides morphotypes 0 <1 (this is an average) 1-4 5-30 >30
Curved Gram variable rods 0 <5 >5

In this scale a score of 0-10 is generated from combining three other scores. It is time consuming and requires trained staff but is has high interobserver reliability:

  • 0–3 is considered negative for bacterial vaginosis
  • 4–6 is considered intermediate
  • 7+ is considered indicative of bacterial vaginosis

Cytology

The Papanicolaou smear is not reliable for diagnosis of bacterial vaginosis.[6]

Culture

Vaginal culture has no role in diagnosis of bacterial vaginosis. [1][7]

References

  1. ↑ 1.0 1.1 1.2 1.3 Center for Disease Control and prevention. Mortality and morbidity weekly reports. Sexually transmitted disease treatment guideline. (2015) https://www.cdc.gov/std/tg2015/tg-2015-print.pdf Accessed on October 20, 2016
  2. ↑ Nugent RP, Krohn MA, Hillier SL (1991). "Reliability of diagnosing bacterial vaginosis is improved by a standardized method of gram stain interpretation". J Clin Microbiol. 29 (2): 297–301. PMC 269757. PMID 1706728.
  3. ↑ Guideline Clearing House. "2002 national guideline for the management of bacterial vaginosis". Unknown parameter |http://www.guideline.gov/summary/summary.aspx?ss= ignored (help)
  4. ↑ Ison, CA; Hay, PE (2002), "Validation of a simplified grading of Gram stained vaginal smears for use in genitourinary medicine clinics", Sex Transm Infect, 78: 413–415
  5. ↑ Nugent, R. P., M. A. Krohn, and S. L. Hillier (1991). "Reliability of diagnosing bacterial vaginosis is improved by a standardized method of Gram stain interpretation". J. Clin. Microbiol. 29: 297&ndash, 301.
  6. ↑ Greene JF, Kuehl TJ, Allen SR (2000). "The papanicolaou smear: inadequate screening test for bacterial vaginosis during pregnancy". Am J Obstet Gynecol. 182 (5): 1048–9. PMID 10819823.
  7. ↑ Stockdale CK (2016). "A Positive Culture Result for Gardnerella Is Not Diagnostic of Bacterial Vaginosis". J Low Genit Tract Dis. 20 (4): 281–2. doi:10.1097/LGT.0000000000000237. PMID 27428605.

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