Urethritis and Cervicitis Flashcards

1
Q

Neisseria gonorrhoeae Physiology and Structure

A
  • Gram-neg. cocci
  • Obligate human pathogen

*no natural animal reservoirs

*doesn’t survive long outside of host

*Fastidious: requires complex media for growth

  • Outer membrane contains LOS (lipooligosaccharide)

*no repeating O antigen

  • Don’t survive outside the human body long (cant get from a toilet seat)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Neisseria gonorrhoeae Virulence Factors

A

All the surface structures on NG undergo extensive antigenic and phase variation

  • Type IV pili
  • Opacity Assoc. Proteins (Opa proteins)
  • Lipooligosaccharide
  • IgA protease
  • Porin Protein (Por A and Por B)
  • Iron binding proteins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Type IV Pili

A
  • Virulence factor of NG
  • Required for infection, mediates binding to mucosal epithelial cells and tissues
  • Mediates natural comopetence and biofilm formation
  • Undergoes extensive intra-strain antigenic and phase variation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Opacity Assoc. Proteins (Opa proteins)

A
  • Virulence factor of NG
  • Promotes attachment and invasion of human cells
  • A single cell can have up to 12 opa genes
  • Undergoes antigenic and phase variation; a single cell can express zero to several diff. Opa proteins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Lipooligosaccharide (LOS)

A
  • Virulence factor of NG
  • Similar to LPS but lacks the long sugar O antigen
  • Toxic to fallopian tube mucosa
  • Sialylation of LOS prevents serum killing
  • Subject to antigenic variaton
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

IgA protease

A
  • Virulence factor of NG
  • Targets and cleaves IgA1
  • Cleaves LAMP1 —> lysosome modification —> survival
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Porin Protein (Por A and Por B)

A
  • Virulence factor of NG
  • Abundant outer membrane protein
  • Allows transport into cell, and contributes to survival
  • PorBIA most commonly assoc. w/ DGI (serum resitance)
  • Protein varies b/w strains
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Iron Binding Proteins

A
  • Virulence factor of NG
  • NG can scavenge iron from transferrin, lactoferrin, and haemoglobin
  • Transferrin binding proteins (TbpA, TbpB): large surface proteins; transferrin receptor required for infection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Neisseria gonorrhoeae Pathogenesis and Immune Response

A
  • Attachment to mucosal cells followed by penetration and multiplication in cells and passage into sub-epithelial space
  • Can survive in leukocytes, get into subepithelial space and produce a PMN rich exudate; its the immune response that is really damaging
  • LOS and peptidoglycan induces TNF-alpha expression and sloughing of ciliated cells (i.e. inflammation)
  • LOS inflammatory response or dissemination
  • A protective immune response is not elicited, and there is no immune memory
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Clinical Syndromes of NG

A
  • Urethritis (males)
  • Cervicitis (females)
  • Disseminated gonococcal infection
  • Pharyngitis
  • Purulent conjunctivitis (mild to aggressive)
  • Proctitis (anorectal gonorrhea)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Ng Urethritis

A
  • Male NG clinical syndrome
  • Uncomplicated mucosal infection
  • 2-5 days incubation —> mucopurulent discharge and dysuria (discharge may be indistinguishable from NGU)
  • Some infections may be asymptomatic
  • Complications (rare): include epididymitis, disseminated gonococcal infection and reactive arthritis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Ng Cervicitis

A
  • Female NG clinical syndrome
  • Commonly asymptomatic (up to 70%)
  • Inflammation of the columnar epithelium and subepithelium of the endocervix
  • When symptomatic: vaginal pruritis and/or mucopurulent discharge. Dysuria is atypical
  • Abdominal pain and dyspareunia: suspect upper genital tract disease (eg. PID)
  • Serious sequelae more common in women: includes salpingitis, PID, and DGI —> sterility, ectopic pregnancy, septic arthritis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Disseminated Gonococcal Infection

A
  • NG clinical syndrome
  • Occurs in 0.5-3% of infected pts. (more common in women)
  • Most that disseminate do not cause urethritis
  • Most common cuase of septic arthritis in sexually active adults
  • Pts deficient in complement components that form the MAC more susceptible
  • Manifestations include:

*dermatitis-arthritis-tenosynovitis syndrome

*septic (purulent) arthritis (one joint)

*rarely, endocarditis, or meningitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Ng Pharyngitis

A
  • NG clinical syndrome
  • Usually acquired by oral sex exposure
  • Majority asymptomatic
  • Symptoms: sore throat, pharyngeal exudates, cervical lymphadenitis
  • Thought to be site of acquisition of antibiotic resistance genes for Ng; we contain commensal neisseria in our throat and so the 2 can exchange genes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Purulent conjunctivitis (mild to aggressive)

A
  • In newborns: opthalmia neonatorum
  • In adults and adolescents: autoinoculation from an anogenital source
  • Non-sexual transmission reported in outbreak settings
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Ng Proctitis

A
  • Ng clinical syndrome
  • Anorectal gonorrhea
  • Usually asymptomatic
  • Males: typically in MSM, uncommon in heterosexual males; assoc. w/ a 3-fold increase in the risk of HIV infection
  • Females: transmission to anal canal from vagina or anal intercourse
  • Symptoms include: tenesmus, anorectal pain, bleeding and mucopurulent discharge
  • Must be distinguished from other infectious causes of proctitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Gonorrhea Diagnostic Techniques

A
  • Should always include testing for Chlamydia (CT)
  • Nucleic acid amplification tests
  • Specimens
  • Microscopy
  • Culture
18
Q

Gonorrhea nucleic acid amplification tests

A
  • NAAT
  • Superior accuracy; can use various specimens
  • Can detect nucleic acid of Ng and CT
  • This method cannot detect antibiotic resistance of Ng
19
Q

Gonorrhea specimen diagnostic techniques

A
  • Vaginal swabs preferred by CDC for asymptomatic females
  • Swabs preferred for extragenital infections (eg. pharyngitis)

*can’t use cotton (toxic to gonorrhea), use plastic

  • First-catch urine: appropriate for asymptomatic females and males regardless of symptomology
20
Q

Gonorrhea microscopic diagnostic techniques

A
  • Gram stain: sensitive (>90%) and specific (98%) in detecting purulent urethritis in men
  • Methylene blue/gentian violet stain
  • Relatively insensitive in women w/ symptomatic or asymptomatic cervicitis
21
Q

Gonorrhea culture diagnostic technique

A
  • Important for testing antibiotic resistance
  • Specimen collection requires use of swabs w/ special hangling b/c of the fastidious nature of Ng (eg. Ng killed by fatty acids and trace metals)
22
Q

Gonorrhea Treatment

A
  • Antibiotic resistance is a major problem
  • Directly Observed Therapy (DOT) whenever possible; watch pt take antibiotic in office
  • Should always include treatment for chlamydia
  • Ceftriaxone 250mg IM + azithromycin 1g PO
  • Cefixime 400mg PO + azithromycin 1g PO

*ONLY if unable to use ceftriaxone

*NOT for pharyngeal infection (low efficacy): TOC recommended for pharyngitis

23
Q

Gonorrhea Prophylactic Treatment

A
  • Routine screening should be offered to sexually active pts at high risk of infection

*eg. young individuals entering correctional facilities

*MSM should be routinely screened for oropharyngeal and rectal Ng

  • Treat pts w/ potential or known exposures empirically
  • Treatment failures: suspect antibiotic resistance, test for w/ culture and antibiotic susceptibility testing
24
Q

Chlamydia Incidence and Harm

A
  • Most common cause of sexually transmitted genital infections
  • Rate of reported cases of chlamydia are highest among adolescents and young adults aged 15-24
  • Rates are underestimated b/c of asymptomatic clinical course
  • Repeat and chronic infections can have a deleterious impact on female reproductive health
  • Highest rates in women
25
Q

Chlamydia trachomatis (CT)

A
  • Obligate intracellular bacteria

*depends on host cell for nutrition and replication

*once thought to be viruses b/c they could pass thru 0.45mm filters

  • Possess inner and outer cell membranes like gram neg. bacteria
  • Unlike other bacteria, do not have a peptidoglycan layer
26
Q

CT Genotypes and Serovars

A
  • Diff. strains; diff. genotypes and 20 distinct serovars
  • 3 main patho-biotypes

*A to C

*D to K

*L1 to L3

27
Q

CT A to C patho-biotype

A
  • Infect ocular epithelium causing acute conjunctivitis to trachoma; endemic in Africa and Asia; characterized by chronic conjunctivitis; leading cause of preventable blindness
28
Q

CT D to K patho-biotype

A
  • Causes STD’s; infect squamocolumnar epithelial cells of female RT and male GU tract (cervicitis, urethritis, proctitis, conjunctivitis, pneumonia (in neonates))
29
Q

CT L1 to L3 patho-biotype

A
  • Lymphogranuloma venereum, a systemic illness; assoc. w/ genital ulcer disease in tropical countries
30
Q

CT Structure and Physiology

A

Exists in 2 morphologically distinct forms:

  • Elementary body (EB): infectious

*spore-like, resistant to harsh environment

*bind to cell receptors for uptake

  • Reticulate body (RB): non-infectious

*metabolically active and replicative

31
Q

CT Pathogenesis

A
  • Infectious EBs enter genital mucosal epithelium of urethra, endocervix, endometrium, fallopian tubes, anorectum, respiratory tract, and conjunctivae
  • Ability of CT to avoid the host immune system is impoprtant for pathogenicity
  • Clinical manifestations due to direct destruction of host cells and a severe host inflammatory response
  • Host immune response (ie. genetic predisposition) is a major determinate of pathology and development of infertility
32
Q

CT Clinical Syndromes

A
  • Urogenital infections
  • Lymphogranuloma venereum (LGV)
  • Conjunctivitis
  • Pharyngitis
  • Genital LGV
33
Q

CT Urogenital Infections in Females

A
  • D-K serovars
  • Clincally the infection includes: cervicitis, urethritis, endometritis, salpingitis, bartholinitis, perihepatitis
  • Most infections asymptomatic (~85%)
  • Symptoms when present are non-specific: change in vaginal discharge, intermenstrual vaginal bleeding, post-coital bleeding
  • Complications: PID, tubal obstruction, and female infertility
  • Most common cuase of tubal infertility and adverse pregnancy outcome, so screening important
34
Q

CT Urogenital Infections in Males

A
  • D-K serovars
  • Most common cause of non-gonococcal urethritis in men

*usually symptomatic: mucoid or watery discharge (sometimes scant, may have to milk the urethra), and dysuria

*one of most frequent pathogens of epididymitis (along w/ Ng)

*Proctitis: inflammation of the distal rectal mucosa; occurs mainly in MSM that engage in receptive anal intercourse. Can be caused by D-K and L serovars (will determine clinical presentation)

  • Reactive arthritis (formerly Reiter’s syndrome)
35
Q

Reactive Arthritis

A
  • Formerly Reiter’s Syndrome
  • Urogenital CT infection
  • Developed by ~1% of men w/ urethritis
  • Known as reactive arthritis triad (RAT: arthritis, uveitis and urethritis)
36
Q

Lymphogranuloma venereum (LGV)

A
  • Caused by serovars L1, L2, L3, usually asymptomatic
  • Historically, genital ulcer disease w/ lymphadenopathy (w/o proctitis) in heterosexuals in tropical and subtropical areas
  • Appears to be more prominent in males
  • Increasingly reported among MSM in temperate climates (outbreaks)

*most HIV (+)

*majority of cases presented as proctitis

37
Q

Lymphogranuloma venereum Stages

A
  • 1st Stage (1-4wks post-infection): a painless ulcer develops at the site of infection that spontaneously heals. Pt may have fever headache, myalgia
  • 2nd Stage (2-6wks later): local extension to inguinal or femoral lymph nodes (inflammation and swelling, Groove sign) —> inguinal buboes which gradually enlarge and may rupture
  • Can spread further thru lymphatics to the rectum (proctitis) and/or progress to invasive infection, often w/ systemic symptoms

*abscesses can form in lymph nodes that suppurate and discharge thru the skin

  • Late lymphogranuloma venereum: if left untreated can lead to other complications
38
Q

CT Conjunctivitis

A
  • Serovars D-K
  • Conjunctival epithelial cells infected by autoinoculation from infected genitalia or by ocular-genital contact
  • Neonatal ocular infections occur during passage thru an infected birth canal and can lead to neonatal pneumonia
39
Q

CT Diagnostic Techniques

A
  • NAAT (diagnostic choice for CT and Ng)

*PCR amplification of RNA or DNA

*Transcription mediated amplification (TMA)

*Strand displacement amplification (SDA)

*XPERT CT/Ng assay-provides results in 90min

*women: first-catch urine, or endocervical or vaginal swabs

  • Culture: Limited to research and reference laboratories
40
Q

CT Treatment

A
  • Uncomplicated cervicitis or urethritis:

*Azithromycin 1gm po, single doese

*-or Doxycycline 100mg po BID x 7 days