Talk:Menstrual Cycle - Histology
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Cite this page: Hill, M.A. (2020, July 14) Embryology Menstrual Cycle - Histology. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Menstrual_Cycle_-_Histology
Papanicolaou smears: to swab or not to swab
Hans N, Cave AJ, Szafran O, Johnson G, Glass A, Spooner GR, Klemka PJ, Schipper S. Can Fam Physician. 2007 Aug;53(8):1328-9.
Cleaning the cervix with a cotton swab does not appear to affect the quality of the conventional Pap smear in terms of adequacy of endocervical cells. This implies that the practice of wiping or not wiping the mucus from the cervix before taking the Pap smear can be employed at the discretion of the clinician.
Comparison between Gram stain and culture for the characterization of vaginal microflora: definition of a distinct grade that resembles grade I microflora and revised categorization of grade I microflora
BMC Microbiol. 2005 Oct 14;5:61.
Verhelst R, Verstraelen H, Claeys G, Verschraegen G, Van Simaey L, De Ganck C, De Backer E, Temmerman M, Vaneechoutte M. Source Department Clinical Chemistry, Microbiology & Immunology, Ghent University Hospital, UGent, Ghent, Belgium. Rita.Verhelst@UGent.be
BACKGROUND: The microbiological diagnosis of bacterial vaginosis is usually made using Nugent's criteria, a useful but rather laborious scoring system based on counting bacterial cell types on Gram stained slides of vaginal smears. Ison and Hay have simplified the score system to three categories and added a fourth category for microflora with a predominance of the Streptococcus cell type. Because in the Nugent system several cell types are not taken into account for a final score, we carried out a detailed assessment of the composition of the vaginal microflora in relation to standard Gram stain in order the improve the diagnostic value of the Gram stain. To this purpose we compared Gram stain based categorization of vaginal smears with i) species specific PCR for the detection of Gardnerella vaginalis and Atopobium vaginae and with ii) tDNA-PCR for the identification of most cultivable species.
RESULTS: A total of 515 samples were obtained from 197 pregnant women, of which 403 (78.3%) were categorized as grade I microflora, 46 (8.9%) as grade II, 22 (4.3%) as grade III and 8 (1.6%) as grade IV, according to the criteria of Ison and Hay. Another 36 samples (7.0%) were assigned to the new category 'grade I-like', because of the presence of diphtheroid bacilli cell types. We found that 52.7% of the grade I-like samples contained Bifidobacterium spp. while L. crispatus was present in only 2.8% of the samples and G. vaginalis and A. vaginae were virtually absent; in addition, the species diversity of this category was similar to that of grade II specimens.Based on the presence of different Lactobacillus cell types, grade I specimens were further characterized as grade Ia (40.2%), grade Iab (14.9%) and grade Ib (44.9%). We found that this classification was supported by the finding that L. crispatus was cultured from respectively 87.0% and 76.7% of grade Ia and Iab specimens while this species was present in only 13.3% of grade Ib specimens, a category in which L. gasseri and L. iners were predominant.
CONCLUSION: Further refinement of Gram stain based grading of vaginal smears is possible by distinguishing additional classes within grade I smears (Ia, Iab and Ib) and by adding a separate category, designated grade I-like. A strong correlation was found between grade Ia and the presence of L. crispatus and between grade I-like and the presence of bifidobacteria. This refinement of Gram stain based scoring of vaginal smears may be helpful to improve the interpretation of the clinical data in future studies, such as the understanding of response to treatment and recurrence of bacterial vaginosis in some women, and the relationship between bacterial vaginosis and preterm birth.
Figure 1. Microscopic image (100 ×) of Gram-stained vaginal smears illustrating the different categories of vaginal microflora described:. a, b: grade Ia, i.e. mainly Lactobacillus crispatus cell types, plump quite homogeneous lactobacilli. c, d: grade Ib, i.e. non-L. crispatus cell types, long or short, thin lactobacilli. e, f: grade Iab, i.e. containing mixtures of L. crispatus and non-L. crispatus cell types. g, h: grade I-like, i.e. irregular-shaped Gram positive rods. i, j: grade II, i.e. mixture of Lactobacillus cell types and bacterial vaginosis-associated bacteria (Gardnerella, Bacteroides-Prevotella and Mobiluncus cell types). k, l: grade III, i.e. bacterial vaginosis.
- grade I - when only Lactobacillus cell types (large Gram positive rods) were present.
- grade II (intermediate) when both Lactobacillus and Gardnerella or Bacteroides-Prevotella cell types were present.
- grade III (bacterial vaginosis) when Lactobacillus cell types were absent and only Gardnerella, Bacteroides-Prevotella or Mobiluncus cell types were present.
- grade IV when Gram positive cocci were predominantly present.
Management of vaginitis
Am Fam Physician. 2004 Dec 1;70(11):2125-32.
Owen MK, Clenney TL. Source Emory University School of Medicine, Atlanta, Georgia, USA.
Common infectious forms of vaginitis include bacterial vaginosis, vulvovaginal candidiasis, and trichomoniasis. Vaginitis also can occur because of atrophic changes. Bacterial vaginosis is caused by proliferation of Gardnerella vaginalis, Mycoplasma hominis, and anaerobes. The diagnosis is based primarily on the Amsel criteria (milky discharge, pH greater than 4.5, positive whiff test, clue cells in a wet-mount preparation). The standard treatment is oral metronidazole in a dosage of 500 mg twice daily for seven days. Vulvovaginal candidiasis can be difficult to diagnose because characteristic signs and symptoms (thick, white discharge, dysuria, vulvovaginal pruritus and swelling) are not specific for the infection. Diagnosis should rely on microscopic examination of a sample from the lateral vaginal wall (10 to 20 percent potassium hydroxide preparation). Cultures are helpful in women with recurrent or complicated vulvovaginal candidiasis, because species other than Candida albicans (e.g., Candida glabrata, Candida tropicalis) may be present. Topical azole and oral fluconazole are equally efficacious in the management of uncomplicated vulvovaginal candidiasis, but a more extensive regimen may be required for complicated infections. Trichomoniasis may cause a foul-smelling, frothy discharge and, in most affected women, vaginal inflammatory changes. Culture and DNA probe testing are useful in diagnosing the infection; examinations of wet-mount preparations have a high false-negative rate. The standard treatment for trichomoniasis is a single 2-g oral dose of metronidazole. Atrophic vaginitis results from estrogen deficiency. Treatment with topical estrogen is effective.
Validation of a simplified grading of Gram stained vaginal smears for use in genitourinary medicine clinics
Sex Transm Infect. 2002 Dec;78(6):413-5.
Ison CA, Hay PE. Source Department of Infectious Diseases and Microbiology, Faculty of Medicine, Imperial College, St Mary's Campus, London, UK. email@example.com
OBJECTIVES: To validate a simplified grading scheme for Gram stained smears of vaginal fluid for the diagnosis of bacterial vaginosis (BV) against the accepted "gold" standard of Amsel's composite criteria.
METHODS: Women attending genitourinary medicine (GUM) clinics, as part of a multicentre study, were diagnosed as having BV if three or more of the following criteria were present; homogeneous discharge, elevated vaginal pH, production of amines, and presence of "clue" cells. Women with less than three of the criteria were considered as normal. Simultaneously, smears were made of vaginal fluid and Gram stained and then assessed qualitatively as normal (grade I), intermediate (grade II), or consistent with BV (grade III). Two new grades were used, grade 0, epithelial cells only with no bacteria, and grade IV, Gram positive cocci only.
RESULTS: BV was diagnosed in 83/162 patient visits using the composite criteria, the remainder being regarded as normal. The majority of patients with BV had a smear assessed as grade III (80/83, 96%) and the majority of normal women had a smear assessed as grade I (normal, 48/79, 61%), giving a high sensitivity (97.5%), specificity (96%), and predictive value for a positive (94.1%) and negative (96%) test, kappa index = 0.91. Smears assessed as grade II were found predominantly (12/13) among patients diagnosed as normal, with less than three of the composite criteria. Grades 0 and IV were both only found among normal women.
CONCLUSION: This simplified assessment of Gram stained smears can be used as an alternative to Amsel's criteria and is more applicable for use in busy GUM clinics.
Diagnosis of bacterial vaginosis in a gynaecology clinic
Br J Obstet Gynaecol. 1992 Jan;99(1):63-6.
Hay PE, Taylor-Robinson D, Lamont RF. Source Division of Sexually Transmitted Diseases, Clinical Research Centre, Harrow, Middlesex. Abstract OBJECTIVE: To estimate the prevalence of bacterial vaginosis in women referred to a gynaecology clinic, and to compare two methods of diagnosing bacterial vaginosis.
SETTING: Gynaecology Clinic at Northwick Park Hospital
SUBJECTS: 114 women aged 16 to 65 referred consecutively to the gynaecology clinic of one consultant.
MAIN OUTCOME MEASURES: Detection of bacterial vaginosis by standard compound criteria and by examination of a Gram stained smear of fluid from the posterior vaginal fornix.
RESULTS: Bacterial vaginosis was detected by both the Gram stain and the compound criteria in 13 women. There was no correlation between the symptom of vaginal discharge and the diagnosis of bacterial vaginosis in this population, but the presence of discharge noted by the clinician was associated with bacterial vaginosis.
CONCLUSIONS: The prevalence of bacterial vaginosis was 11%. The Gram stain provides a simple and inexpensive method for laboratory confirmation of bacterial vaginosis where facilities for using the compound criteria are not available.