UTIs/STIs - Mclean Flashcards
(23 cards)
Mycoplasma
Lack rigid cell wall
Very small
pleomorphic
require cholesterol
fried egg appearance
Chlamydia
thot to be viruses
very little peptidoglycan, have 2 lipid bilayers.
Life cycle of chlamydia.
elementary body will infect cell (EB)
will convert to reticulate body (RB) - metabolic active. This is what divides.
eventually convert back to EB -> release from cell, infect others.
How to differentiate between chlamydia trachomatis and other chlamydia
inclusions contain glycogen.
Chlamydia trachomatis:
serotypes ABC affect:
DK affect:
L1 L2 L3 affect:
Important slide
eyes (disease known as Trachoma)
genitals (STI’s)
genitals (STI’s)
Chlamydia trachomatis:
serotype D-K facts
most common bacterial STD in USA
males: inflammation of urethra, anal , rectal
females: cervix can be inflammed, maybe in fallopian tube too.
Symptoms: Chlamydia: more clear discharge than gonorrhea.
Gonorrhea: more pus-like discharge.
Eyes: Inclusion conjunctivitis. Conjunctiva of eyes are affected. Mucous / pus coming from eyes. (acute)
QUESTIONS ON MIDTERM REVOLVE AROUND DIAGNOSIS AND TREATMENT.
Chlamydia trachomatis:
Serotypes L1, L2, L3 facts
Cause Lymphogranuloma Venereum (LGV)
more rare. More invasive than D-K.
Primary stage: local infection. can be transffered skin to skin
Secondary stage: dissemination. swelling of inguinal / perirectal lymph nodes
tertiary stage: progressive tissue damage. Ulcers, fistulas, more.
Chlamydia trachomatis
Serotpes A, B, C facts
major cause of blindness in asia africa
more chronic
causes Trachoma
scarring of cornea
repeated infections: eyelids being turned inwards. scratches surface of eye.
Diagnosis of chlamydia trachomatis:
Treatment:
important slide
Diagnosis: NAAT (nucleic acid amplification test)
Microscopy using direct fluorescent antibody staining
Treatment: doxycycline. It is a tetracycline antibiotic, targets protein synthesis.
Erythromycin / azithromycin for small children. Don’t want to use tetracycline bc it binds to ca2+ in teeth, which becomes yellow.
Azithromycin for pregnant.
Neisseria: meningitidis, gonorrhoeae.
Morphology:
Morphology: gram negative diplococci
Meningitidis is the one with a capsule***
Gonorrhoeae is the one without.
There is a vaccine for meningitidis but not gonorrhea. Vaccine is against capsule.
Cultivation of meningitidis / gonorrhea
Meningitidis: use on chocolate agar bc its non selective
Gonorrhea: use on thayer-martin agar bc its more selective.
Plasmids / B-lactamase production in Neisseria gonorrhea / miningitidis
gonorrhea: commonly have plasmids, commonly have B-lactamase production
Meningitidis: few plasmids, no b-lactamase production
bc gonorrhea have common of those two, they are becoming highly resistant to antibiotics.
6 important virulence factors with meningitis / gonorrhea
1.) capsule (meninigitis)
2.) Pili: attachment
3.) lipo-oligosaccharide (LOS). (shorter / more branching than LPS)
4.) Opacity proteins: prevent phagocytosis
5.) Porin (protein 1): associated with attachment.
6.) IgA protease: cleaving IgA
IgA is the antibody that protects mucosal surfaces. So if u can cleave it, theres less protection.
Treatment of gonorrhea:
1% silver nitrate, erythromycin
gonorrhea is pus-like, burning during urination (urinating razorblades)
Diagnosis of gonorrhea:
Treatment:
NAAT.
Culture on Thayer Martin agar
Gram stain: Gram negative organism. look for diplococci
Ceftriaxone injection is first choice
Doxycycline is added if coinfection with chlamydia trachomatis not ruled out
Spirochetes
general characteristcs
possess endoflagella for motility
gram negative, spiral shaped
treponema: regular coils, tight.
Spirochetes: signs symptoms:
T. pertenue:
T. carateum
T. denticola
T. pallidum:
T. pertenue: yaws in tropics. infection of skin bones joints
T. carateum: pinta. skin disease
T. denticola: present in mouth, implicated in gingivitis, acute necrotizing ulcerative gingivitis
T. pallidum: cause syphilis ***
T. pallidum: syphilis
different stages
primary stage: non-tender, indurated ulcer. (sore)
Secondary stage: rashes all over
Latent syphilis: can last 30 years
Tertiary phase: no organ of body is immune. gummatous disease, nervous system affected.
T. pallidum: syphilis
diagnosis:
darkfield microscopy can see spiral organisms
direct fluorescent antibody test: find antigen
blood tests: anti-treponemal antibody test: look for antibodies specific to antigen
non-treponemal antibody test (reagin): look for antibodies of damaged cells. Not as accurate. VDR test: use microscope. RPR test: agglutination. no microscope.
Treatment of syphilis
Benzathine penicillin G
Trichomoniasis:
caused by trichomonas vaginalis:
Most prevalent non viral STI
treatment: metronidazole
Bacterial Vaginosis (BV)
not an STI. disruption of normal flora.
treatment: metronidazole
