1. What are the agents that can cause vaginitis?
-
Candidiasis
-
Trichomonas
vaginalis
-
Bacterial vaginosis
-
Neisseria gonorrhea
2. What are the distinguishing characteristics of each.
-
Trichomonas
vaginalis , a protozoan that produces a foamy, malodorous yellow-green
discharge,
-
Bacterial vaginosis, caused by anaerobic bacteria such as
Bacteroides, Mobiluncus, and gram negative bacteria such as Gardnerella
vaginilis. A white discharge with fishy odor and clue cells on microscopic
examination help establish this diagnosis.
-
Neisseria gonorrhea, which
produces a vaginal discharge in conjunction with a cervicitis.
3. What diagnostic procedures are helpful in establishing the etiology of
vaginitis?
- Demonstration of a normal pH, the absence of any other pathogen,
presence of yeast and/or pseudohyphae, establish the diagnosis of Candida
vaginitis.
- The addition of 10-20% KOH is helpful in lysing other epithelial
cells and aiding in visualizing yeasts or pseudohyphae; in 30-50% of
infected women direct microscopic examination fails to demonstrate Candida
and a presumptive diagnosis must be made.
- Most routine media will grow
Candida.
- The formation of germ tubes, on incubation for 90 min in serum
allows a presumptive identification of albicans. Further biochemical tests
are required to differentiate the non albicans Candida species.
-
"Yeast" forms are budding blastoconidia and
"Pseudohyphae" which are elongated processes arising from
blastoconidia and possess different chemical and enzymatic properties.
-
The
pseudohyphae are seen in association with invasive forms of tissue
infection.
4. What is the likely diagnosis?
5.. What factors facilitate causation of disease by this organism? Which of
these was most important in our patient?
- Colonization is aided by the ability of Candida to adhere to mucosal
surfaces.
- Overgrowth of Candida may be facilitated by high estrogen levels
particularly in pregnancy.
- Normally ,other flora (bacteria) resident on
mucosal surfaces prevent uncontrolled proliferation by Candida, high
population density and subsequent disease are facilitated by suppression of
normal flora by antibacterial agents, such as ampicillin treatment in our
patient.
- Pseudohyphae bind to components of the extracellular matrix;
proteinases help in invasion and adherence.
- High sugars in diabetics enhance
production of surface adherence proteins such as mannoproteins of the outer
fibrillar surface of Candida.
- Disruptions of skin and mucosal surfaces
expose components of the ECM to which Candida can bind. Corticosteroids and
depressed T cell immunity also predispose to local and invasive disease.
6. What are the treatment options for this patient?
- Topical clotrimazole, miconazole, tioconazole, butoconazole,
econazole, terconazole, fenticonazole, nystatin.
- Oral ketoconazole,
itraconazole and fluconazole.
7. What other syndromes are caused by this pathogen?
- Oropharyngeal candidiasis (thrush)
- esophagitis
- skin infections in
moist areas
- chronic mucocutaneous candidiasis associated with T cell
defects
- UTI
- retinitis and
- endophthalmitis
- catheter infections
- endocarditis
- rarely pneumonia and
- surgical wound infections
8. What other Candida species are associated with human diseases?
- C krusei
- C parapsilosis
- C tropicalis
- C guillermondii
- C glabrata
also known as Torulopsis glabrata