Transcript Gonorrhoea

Gonorrhoea
• -Gonorrhoea is caused by infection with Neisseria gonorrhoeae, a Gramnegative, intracellular diplococcus.
• -The mode of transmission is almost exclusively by sexual contact. This
organism adheres primarily to the mucous membranes of the urethra,
endocervix, rectum, pharynx and conjunctiva.
• - Gonorrhoea may co-exist with other genital mucosal pathogens, notably
C. trachomatis, T. vaginalis and C. albicans.
• -Up to 80% of initial cases of PID are caused by N. gonorrhoeae or C.
trachomatis, or both.
• - Although uncommon, gonorrhoea may also cause disseminated systemic
disease and arthritis.
• -The most common symptom is an increased or altered vaginal discharge
although up to 50% of women are asymptomatic.
• -Lower abdominal pain, dysuria, intermenstrual bleeding and menorrhagia
may also be experienced, ranging in intensity from minimal to severe
Gonorrhea in pregnancy
-Infection with N. gonorrhea has been •
associated with adverse pregnancy outcomes.
-These include low birthweight, pre-term •
rupture of membranes, pre-term birth,
chorioamnionitis and postpartum
endometritis and salpingitis.
- Other possible complications are •
spontaneous miscarriage and secondary
infertility .
Neonatal infection
-N. gonorrhoeae is usually transmitted from the mother's genital •
tract to the baby at the time of birth although occasionally it may
occur in utero when there is prolonged rupture of the membranes.
- The risk of transmission from an untreated mother is about 30– •
50%.
-Infection usually manifests as ophthalmia neonatorum with a •
purulent discharge usually evident within 2–5 days of birth.
-It can be diagnosed by microscopy and culture of an eye swab. •
- The eyes may be cleaned with saline but systemic antibiotics are •
required.
- If left untreated the condition can lead to corneal ulceration and •
perforation with permanent loss of vision.
-Occasionally the neonate may develop gonococcal arthritis and/or •
disseminated infection.
Diagnosis and treatment
The methods used to diagnose gonorrhea consist of: •
microscopy of a suitably stained specimen • •
culture for N. gonorrhoeae on a medium with
• •
antimicrobial agents
nucleic acid hybridization or amplification tests. • •
-In women, microscopic examination of Gram-stained •
endocervical smears is the first-line in diagnosis.
-Specificity is high (>99%) when screened by trained •
personnel. Microscopy is unsuitable for pharyngeal and
rectal specimens because of the presence of other Gramnegative cocci
Culture for N. gonorrhoeae can be undertaken with •
specimens from all sites.
-This method provides a viable organism for antibiotic sensitivity testing. •
- Culture has been reported to have a sensitivity of 85–95% for urethral and •
endocervical infection
-Nucleic acid hybridization or amplification tests are not currently recommended •
for use in GUM clinics because of the inability to assess antibiotic sensitivity.
-Penicillin has been used as a first-line therapy for gonorrhoea for many years. •
- However, surveillance data in the UK show that N. gonorrhea is becoming •
resistant to penicillin, tetracyclines and ciprofloxacin (a quinolone)
-Nevertheless, local patterns of antimicrobial sensitivity should be taken into •
account when prescribing treatment.
- If antimicrobial sensitivity to the above antibiotics is known then ciprofloxacin, •
ofloxacin and ampicillin plus probenecid may be prescribed in oral, single doses.
- Otherwise, third-generation cephalosporins such as ceftriaxone or cefixime •
should be prescribed orally or intramuscularly in single doses. Spectinomycin may
also be given in a single oral dose.
- Pregnant women should not be treated with quinolone or tetracycline •
Group B streptococcus
-Group B streptococcus (GBS) (Streptococcus •
agalactiae) is a Gram-positive bacterium that naturally
colonizes the body.
-It is harboured in the genital and gastrointestinal •
tracts and carried asymptomatically in up to 40% of
adults
- GBS is not considered to be sexually transmitted but •
infection increases with sexual activity and rates are
highest in women attending genitourinary clinics.
-Approximately 12–26% of pregnant women are •
colonized with the organism
Group B streptococcus in pregnancy
-In pregnant women colonized with GBS, high risk •
factors associated with vertical transmission include:
pre-term delivery, prolonged rupture of membranes, •
maternal pyrexia during labour,
-GBS cultured in a urine sample, known carriage of GBS •
or a history of a GBS infection in a previous pregnancy
- GBS is able to infiltrate the amniotic cavity, whether •
or not the membranes are intact, and infect the fetus
through the lung epithelium.
- Postpartum endometritis and post-caesarean wound •
infection may also occur in the mother.
Fetal and neonatal infections
• -GBS is the leading cause of serious neonatal
infection
• -The prevalence of early onset GBS disease in the
UK is estimated to range from 0.5/1000 to
1.15/1000 live births
• -Early onset is when symptoms develop within
the first 5 days of life (average 20 hrs) suggesting
that the infection started in utero.
-Late onset usually presents between 7 days and •
3 months of age in previously healthy babies
Diagnosis and treatment
-The identification of women colonized with GBS •
can reliably be undertaken with vaginal and rectal
swabs.
-In the USA, pregnant women are screened in the •
third trimester for GBS and are treated
prophylactically with intrapartum penicillin if
identified as high risk of transmitting the
infection.
- However, pregnant women in the UK are not •
routinely screened because evidence of clinical
and cost-effectiveness remain uncertain
Syphilis
Syphilis is an acute and chronic sexually transmitted •
infection caused by the bacterium Treponema
pallidum, a spirochaete.
- It can also be transmitted transplacentally to the fetus
from the 9th week of gestation onwards
-It is a common infection worldwide with an estimated
12 million diagnosed new cases each year.
-Syphilis is a complex systemic disease that can involve
virtually any organ in the body.
-Acquired syphilis is classified into the following stages
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Early (infectious) syphilis
Primary: 9–90 days after exposure (mean 21 •
days)
Secondary: 6 weeks-6 months after • •
exposure (4–8 weeks after primary lesion)
Latent (early): <2 years after exposure. • •
Late (non-infectious) syphilis
Latent (late): > 2 years after exposure with no symptoms or
• •
signs
Tertiary, gummatous, cardiovascular, neurosyphilis: 3–20 years
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after exposure.
Syphilis in pregnancy •
-WHO figures estimate that maternal syphilis adversely affects 1 •
million pregnancies each year, with 460 000 resulting in abortion or
perinatal death, 270 000 babies being born with congenital syphilis
and 270 000 being born premature or with low birthweight
-In the UK, antenatal screening for syphilis is routine and the •
incidence of infectious syphilis is low although there is no
systematic national surveillance for the number of cases diagnosed
during pregnancy
report an incidence of 0.2% in London and 0.02% •
in the rest of the UK. The prevalence in Northern
Europe is between 0.02% and 4.5%
-Vertical transmission may occur at any time •
during pregnancy in untreated early syphilis but
the risk of transmission diminishes as maternal
syphilis advances.
-The rate of vertical transmission in untreated •
women is 70–100% for primary syphilis, 40% for
early latent syphilis and an estimated 10% for
mothers with late latent syphilis
Congenital syphilis
-The prevalence of congenital syphilis in the UK is estimated as very •
low.
- It is classified into early or late congenital syphilis depending on •
whether it presents before or after 2 years of age.
- It is associated with serious neurological, developmental and •
musculoskeletal sequelae and the prognosis is considered poor if
symptoms present in the first few weeks of life
-Diagnosis may be complicated because more than half of all infants •
are asymptomatic at birth, and signs in symptomatic infants may be
subtle and non-specific.
-Characteristically, prematurity, low birth weight, hepatomegaly •
with or without splenomegaly and failure to thrive are some of the
findings of early syphilis, although these signs are also seen in other
congenital infections
-Serological tests should be performed on the baby's blood •
not cord blood.
-A positive anti-treponemal EIA IgM is consistent with a •
diagnosis of congenital infection although positive tests
should be repeated to confirm this.
-A negative IgM test should be repeated at 4, 8 and 12 •
weeks as the IgM response could be delayed or suppressed
-Babies born to mothers treated antenatally for syphilis •
should be managed jointly with paediatricians and followed
up at 3 months, 6 months and 1 year.
-UK guidelines suggest that older siblings should also be •
screened for congenital syphilis
-Treatment is usually with penicillin. •
Diagnosis and treatment
-Women in the UK are screened for syphilis at antenatal booking •
and treated if needed in the same way as non-pregnant women.
- However, this does not detect those who acquire the infection •
during pregnancy, or are incubating syphilis at the time of
serological testing.
-There are two main classifications of serological tests for syphilis •
Non-treponemal tests which detect non-specific treponemal •
antibodies:
Venereal Diseases Research Laboratory (VDRL)
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Rapid plasma reagin (RPR) tests.
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Treponemal tests which detect specific treponemal antibodies: •
Enzyme immunoassays (EIAs)
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T pallidum haemagglutination assay (TPHA)
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T pallidum particle agglutination assay (TPPA)
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Fluorescent treponemal antibody-absorbed test (FTA-abs).
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-If syphilis is suspected on the basis of clinical findings, dark-field •
microscopic examination or fluorescent antibody staining of a
specimen taken from a lesion should be undertaken
- A Cochrane systematic review of antibiotics for syphilis diagnosed •
during pregnancy concluded that penicillin is effective in the
treatment of syphilis and the prevention of congenital syphilis but
more research is needed on the best dosage and duration of
treatment
- The management of pregnant women with syphilis should •
be undertaken jointly between a GUM physician and
obstetricians and midwives.
- In the case of penicillin allergy, tetracycline is the second- •
line treatment but this is contraindicated in pregnancy.
- Erythromycin or azithromycin are alternatives but these •
may be ineffective in treating pregnant women
-Desensitization to penicillin should therefore be •
considered as an option.
-Breastfeeding is safe unless an infectious lesion is present •
on the breast
-Patients should be warned of possible reactions to •
treatment with penicillin.
The Jarisch–Herxheimer reaction is an acute febrile illness characterized •
by fever, chills, myalgia, headache, hypotension and tachycardia that
occurs in up to 45% of pregnant women after treatment for early syphilis.
-The release of pro-inflammatory cytokines in response to dying organisms •
is thought to induce this reaction.
-Symptoms may occur within several hours of treatment but resolve •
within 24–36 hrs.
- In pregnant women, it can cause uterine contractions, fetal distress and •
precipitate pre-term labor.
- For this reason some recommend that the mother is admitted to hospital •
for the first 24 hrs of treatment
-Women who are known to have been treated for syphilis in the past do •
not require treatment in subsequent pregnancies if there is no clinical or
serological evidence of infection but the baby should be tested to exclude
congenital syphilis