Transcript Lab 17-Genital

‫بسم هللا الرحمن الرحيم‬
L/O/G/O
Diagnostic Medical Microbiology-Laboratory Manual
Genital Culture
Genital culture
 Is the use of enrichment and selective media to isolate and
identify organisms that cause genital infections such as
Urethritis, Cervicitis, Endometritis, Prostatitis, Vaginitis and
salpingitis (Fallopian tubes infection).
 A genital culture allows the organisms present in the genital to
grow to levels enabling identification.
Type of specimen:
Swab of vagina, cervix discharge, aspirated
endometrial, prostatic fluid, or urethral discharge.
endocervical,
Pathogenic bacteria
Commensals bacteria
Neisseria gonorrheae
Group B Streptococci
Gardnerella vaginalis
Enterococcus spp.
Certain anaerobes including
Actinomyces spp.
Haemophilus ducreyi
Treponema pallidum
Mycoplasma spp.
Enterobacteriaceae
Chlamydia trachomatis
coagulase negative Staph
Corynebacterium spp.
E.coli and other coliform
Many species of anaerobic
Fungi
Candida albicans
Parasite
Trichomonas vaginalis
Viruses
Herpes simplex virus
Human papilloma virus
Pre specimen processing
Who is authorized to order the test
Physician.
Time relapse before processing the sample
According to the type of swab ( recommended within 30 min).
Storage
Maintain specimen
refrigerate.
swab
at
room
Quantity of specimen
Sufficient amount on swab or aspiration.
temperature.
Do
not
Specimen processing for Genital specimen
Vaginitis
 Inflammation of the vaginal mucosa called vaginitis.
 Women who present with vaginal symptoms often complain of
an abnormal discharge and possibly other symptoms such as
offensive odor and itching.
 The three most common cause of vaginitis in premenopausal
women are vaginal candidiasis, bacterial vaginosis and
trichomoniasis.
Bacterial vaginosis
BV is caused by an imbalance of naturally occurring bacterial flora
of vagina.
Specimen processing for Vaginal swab
Bacterial Vaginosis
 Non-cultural diagnosis can be made by detection at least three
of the following four characteristics:
I.
Thin, homogeneous discharge adhering to the vaginal wall.
II.
pH greater than 4.5.
III. odor intensified on addition of 10% potassium hydroxide.
IV. Presence of clue cells by microscopic examination of the
discharge.
Bacterial Vaginosis
 A Whiff test Several drops of 10 % a potassium hydroxide
(KOH) solution may also be added to a sample of the vaginal
discharge to test for any resultant strong fishy (amine) odor
from the mix, which would indicate bacterial vaginosis.
 pH measuring by using litmus papers, Normal vaginal pH is
between 3.8-4.5 pH.
At least 10–20 high power (1000× oil immersion) fields are
counted and an average determined.
Clue cells
 Clue cells are vaginal squamous epithelial cells coated with
coccobacilli gram variable Gardnerella vaginalis adhering to their
surface and sometimes obscuring their borders.
 Clue cells indicate bacterial vaginosis.
I.
II.
Mix a drop of vaginal fluid with a drop of saline on a glass slide.
Place a coverslip over the suspension and examine the
preparation microscopically at x 400 magnification.
III. Clue cells are squamous epithelial cells covered with many
small coccobacillary organisms ,giving a stippled, granular
aspect the edges of these epithelia cells are not clearly defined
, owing to the large number of bacteria present .
Clue cells Wet mount
Clue cells Gram Stain
Normal Vaginal Gram Stain
Bacterial Vaginosis Garm Stain
Candidiasis or Candida Vaginitis
 Diagnosis is confirmed either by a simple wet mount, or better, a
10% potassium hydroxide wet mount microscopy and culture.
 Candida albicans is the major cause accounting for 85% of the
isolates.
Wet mount and KOH smear
KOH slide A sample of the vaginal discharge is placed on a slide and
mixed with a solution of 10% potassium hydroxide (KOH). The KOH kills
bacteria and cells from the vagina, leaving only yeast for easier detection
of a yeast infection.
Sabouraud Dextrose agar
Ingredients:
I. Digest of casein.
II. Digest of animal tissue.
III. Dextrose. 4 %
IV. Agar 1.5 %
Final pH 5.6 ± 0.2 at 25°C
Sabouraud Dextrose agar is used for the isolation, cultivation, and
maintenance of saprophytic and pathogenic fungi.
It supplies peptone as the protein source and dextrose as the
carbohydrate source for nourishment .
Bacterial suppression occur due to the low pH (5.6) pH.
Note: chloramphenicol may use to inhibit growth of bacteria.
Candida albicans on Sab. agar
Candida appears as large, round, white or cream (albicans is from
latin meaning 'whitish') colonies with a yeasty odor on agar plates.
Trichomoniasis or Trichomonas Vaginitis
Trichomonas vaginalis
Thayer - Martin agar
 Chocolate agar has been modified to be selective for Neisseria
gonorrhoeae and Neisseria meningitidis by the addition of
antibiotics, (V-C-N inhibitor) including:
 Colistin: to inhibit most gram negative bacteria other than Neiseria.
 Vancomycin: to inhibit most gram positive bacteria.
 Nystatin or anisomycin :to inhibit yeast.
 Modified Thayer - Martain agar includes trimethoprim to inhibit
Proteus.
Neisseria gonorrhoeae
Typical colonial morphology on Thayer-Martin Selective Agar of
Neisseria gonorrhoeae .... Small, grayish-white to colorless, mucoid
Jembec plate
In the JEMBEC system, a tablet consisting of a mixture of citric acid and sodium
bicarbonate is placed in a well within the plate and is activated by the moisture
(humidity) produced by the culture medium within the sealed plastic bag. The
CO2 levels generated are sufficient for the growth of Neisseria gonorrhoeae on
the selective medium provided with the system
Neisseria gonorrhoeae Gram stain
Direct Immuno fluorescence (DIF) Antibody labeling
for Neisseria gonorrhoeae
Direct Immuno fluorescence (DIF) Antibody labeling
for Chlamydia trachomatis
Chlamydia trachomatis
With Giema stain
Giemsa stain of Chlamydia inclusion
bodies (purple "caps" on epithelial cell).
With Iodine stain
Post specimen processing
Interfering factors:
 Patient on antibiotic therapy.
 Improper sample collection.
Result reporting:
 Report Gram stain finding as an initial report.
 Report the isolated and its sensitivity pattern as a final report.
Turn around time:
 Gram stain result should be available half hour after specimen
receipt.
 Isolation of a possible pathogen can be expected after 2-3 days.
 Negative culture will be reported out 1-2 days after the receipt of
the specimen.
End of Lecture