STD's Flashcards
List the sexually transmitted diseases
Chlamydia Ghonnorhea Trichinomas vaginalis PID Genital herpes Genital warts HIV Syphillis
What causes genital herpes
Herpes simplex virus.
transmitted via skin-to-skin contact -vaginal, anal or oral sex
virus can lie dormant until it recurs later in life causing recurrent outbreaks.
Pathophysiology behind genital herpes
Two types of HSV
HSV1: Genital & Oral herpes
HSV2: Genital herpes
HSV enters the body through small cracks in the skin or through the mucous membranes of mouth, vagina, rectum, urethra or under the foreskin.
After infecting the surface, the virus travels up the nearest nerve to the ganglion and remains there.
Remains dormant for long, as here it cannot be reached by the immune system.
During the reactivation of the virus, it travels back down the nerve onto the surface of the genitals once again to cause a symptomatic outbreak.
How does HSV spread even when people are unaware of infection
Asymptomatic shedding
When the virus multiplies and becomes transmissible without stimulating an immune response from the host and thus no symptoms are present
HSV is notorious for this and up to 1/3 of all transmissions occur this way
Risk Factors for genital herpes
multiple sexual partners
oral sex with a partner suffering from cold sores
Barrier contraception reduces risk but transmission is still possible especially by areas not covered by condoms e.g. THIGHS
Sx of genital herpes
Primary infection symptoms
Secondary (recurrent) infection symptoms
Cold sores
Primary infection symptoms of herpes
1)Small red blisters around the genitals that are very painful and can form open sores
HEAL AFTER 20 DAYS
-F: vulva, clitoris, buttocks and anus
-M: penis n same
2) Vaginal or penile discharge
3) Flu-like symptoms, fever, muscle aches
4) Itchy genitals
Secondary (recurrent) infection symptoms of herpes
recurrent outbreaks are shorter and less severe and over time outbreaks usually reduce in severity and length.
due to antibody production increasing recognition of the virus and increasing the effectiveness of response.
1) Burning and itching around the genitals
2) Painful red blisters around the genitals
Cold sores
They are mainly caused by HSV-1 and can be occasionally caused by HSV-2.
painful lesions around the mouth and nose that last between [[7-10 days]].
usually dormant with outbreaks occurring up to a few times a year.
If someone suffering from cold sores gives oral sex to a partner, the partner is at risk of contracting genital herpes as a result.
The dormant aspect of the infection means people may contract herpes from a partner without knowing. As a result this can make a diagnosis of genital herpes quite shocking and very difficult for a patient.
Dx of genital herpes
Genital ulcer sx
1) aphthous ulcers
2) varicella-zoster virus
3) trauma
[[more than 5 outbreaks]] of genital herpes in one year
indicate a weakened immune system and therefore an underlying diagnosis of HIV.
Dg of herpes
History
– sexual partners,
- history of cold sores
- history of any other STIs.
Swab from the open sore –
- This swab will be tested for the presence of HSV and - -PCR can differentiate between type 1 and 2.
- Even if this swab is negative, the diagnosis of herpes can still be made later on if flare-ups persist.
Other Sti
- screen for other possible std’s especially if history is suggestive
Management of genital herpes
Primary infection
1) Aciclovir:: reducing the number and size of the lesions caused by HSV
2) sexual health advice
- no sex during outbreaks
- disclose it to recent/ current partners
Recurrent outbreaks
1) [[Episodic rx]] w/ aciclovir whenever outbreaks occur
2) Over the counter painkillers, petroleum jelly and ice packs
Over 5 outbreaks a year // Severe outbreaks
-Suppressive rx : daily doses of aciclovir to prevent new outbreaks.
What happens to a woman with Genital herpes who gets pregnant
The mother should maintain rx w/ Aciclovir but the baby should be protected from acquiring the infection due to the antibodies she will pass to the foetus through the placenta.
c/S can be offered as the risk of the baby acquiring HSV transvaginally is 0-3%
What happens if a mother contracts Herpes herself in the last trimester of pregnancy
more dangerous for the baby as the mother has not produced antibodies to pass onto the growing foetus.
baby is a lot more likely to contract herpes during vaginal birth (2/5 chance) and so a caesarean section is recommended in this circumstance.
3 Forms of neonatal herpes
1) SEM:=skin, eyes and mouth herpes
2) DIS= disseminated herpes affecting the internal organs!
3) CNS herpes = affecting the nervous system and the brain and can lead to !!encephalitis!!
Aciclovir is sufficient for SEM herpes but mortality is estimated to be much higher for DIS and CNS herpes, especially if undiagnosed for some time.
What are genital warts
benign epithelial or mucosal outgrowths caused by DNA human papilloma virus (HPV).
How many types of HPV are there
over 100 types of the human papilloma virus, responsible for different types of warts.
More than 40 types of HPV have been associated with anogenital warts (condyloma acuminatum)
however HPV6 and HPV11 are responsible for roughly 90% of cases.
Pathophysiology of genital warts
spread through skin-to-skin contact during vaginal and anal sexual intercourse,
however penetrative sex is not necessary for transmission!!
——In rare cases it can be passed on from the hand to genitals, during oral sex and to the neonate during delivery.
It is important to note that condoms do not fully protect against HPV as not all skin is covered e.g. the inner thighs just like herpes
virus penetrates the epithelial barrier and !!infects basal keratinocytes!!!.
Within the keratinocyte the virus replicates resulting in multiplication of the keratinocyte and this rapid growth manifests as lesions.
Risk Factors for genital warts
Sim to other std’s and cervical cancer
Early age at first sexual intercourse Multiple partners Immunosuppression Smoking Diabetes associated with persistence of warts
Clinical Features of genital warts
Onset of weeks to years
painless, fleshy growths that can be soft or hard and can be singular or multiple.
Can also cause extragenital lesions in oral cavity, larynx, conjunctivae and the nasal cavity.
Most are assyx and spontaneously resolve
Dx of genital warts
Vestibular papillomatosis:
-projections of the vestibular epithelium or labia minora
Dx sx: non-viral and not sexually transmitted
Dx dg: Application of acetic acid does not change their colour – HPV lesions turn whitish.
Molluscum contagiosum: viral infection causing small firm raised papules on the skin.
What is vestibular papilomatosis
https://www.healthline.com/health/vestibular-papillomatosis
Dg work up of genital warts
Colposcopy and biopsy IF neoplasms suggested
Vaginal speculum
Proctoscopy - Anal lesions
Rx of genital warts
Lesion usually resolve especially postpartum
2 types: Topical rx & Physical ablation
Topical rx
Podophyllotoxin:
twice daily for 3 days followed by 4 days rest (4-5 cycles)
Clusters of small warts, better for non-keratinised lesions
Imiquimod:
3 times weekly and wash off after 6-10 hours (up to 16 wks)
Larger warts, particularly keratinised warts
C.I on topical rx of warts
Topical treatments may weaken latex condoms.
They are also contraindicated in pregnancy and breastfeeding, and may cause local inflammation.
Physical ablation for rx of warts
Excision: Pedunculated/large warts or small hard warts
-surgical removal under local anaesthetic
Cryotherapy: Multiple small warts
-freezing using liquid nitrogen usually repeated weekly (consider alternative treatment if no response after 4 weeks)
Electrosurgery: Large warts that have failed to respond to topical treatment
-excision removes the majority of the wart and then an electric current is passed through a metal loop pressed against the wart to remove any remaining part
Laser surgery: Difficult to access warts e.g. inside the anus
-a laser is used to burn the warts under local or general anaesthetic.
Vaccination against HPV
HPV vaccine is offered to all girls aged 12-13. This was introduced in 2008 and the vaccine originally protected against the high risk HPV types 16 and 18, however since 2012 the vaccine Gardasil® additionally protects against the most common types HPV 6 and 11.
The vaccine is most beneficial if administered before first sexual contact.
It is argued that only immunising females will not necessarily protect males and herd immunity will not apply to men who have sex with men.
In some countries, Gardasil is administered to both males and females.
How does HPV affect pregnancy
HPV is not associated with miscarriage, premature birth or other pregnancy complications.
due to the hormonal changes associated with pregnancy, genital warts may multiply or enlarge.
Treatment is to reduce the burden of lesions so that during childbirth the neonate’s exposure is reduced.
physical ablation methods are preferred during pregnancy .
Can HPV be transmitted to the baby
The risk of transmission to the neonate during birth is extremely low
If transmission does occur then the immune system will usually clear the virus
in rare cases the baby may develop
respiratory papillomatosis!!!
where genital warts develop in the throat.
What is HIV
human immunodeficiency virus (HIV).
a single stranded RNA retrovirus that infects and replicates within the human immune system using
host [[CD4]] cells.
Without treatment, destruction of the immune system can lead to acquired immune deficiency syndrome (AIDS).
Pathophysiology of HIV
penetrates the host CD4 cell and empties its contents.
viral RNA are converted into double stranded DNA by reverse transcriptase, and combined with the host DNA using the enzyme integrase.
The viral DNA is read, creating viral protein chains and the immature virus pushes out of the cell [retaining some cell membrane]
virus becomes mature when the protease cuts the viral protein chains, to create a working virus.
The t helper cell is destroyed during this process.
What changes viral RNA. To DNA in Host CD4 cells
reverse transcriptase
What enzyme integrates viral DNA into host DNA after conversion
enzyme integrase.
What enzyme causes the maturation of the HIV virus
Protease during the cleavage of viral proteins and subsequent death of CD4 cells
How do CD4 levels change in response to HIV
A normal range for CD4 cells is about 500-1,500.
Initial phase
-CD4 levels fall in response to the initial, rapid replication of HIV – and at this stage a person is extremely infectious. This is marked by flu like symptoms d/2 seroconversion
Latent phase begins after months- years
-patientinitially be asymptomatic, but with CD4 levels falling and viral load increasing, they may become more susceptible to infections and can later become symptomatic
AIDS
- over an average of 10 years,
- CD4 drops to below 200
What are the four ways HIV is transmitted
Unprotected sexual contact – vaginal, anal or oral.
Sharing of injecting equipment.
Medical procedures – blood products, skin grafts, organ donation and artificial insemination.
Vertical transmission – from mother to child in utero, during childbirth or breast feeding.
Risk groups for HIV
Men who have sex with men
Intravenous drug users
Those in high prevalence areas
Those who have had unprotected sex with a partner who has lived or travelled in Africa
Classification of Sx of HIV
Seroconversion Illness
Symptomatic HIV
AIDS sx
List the seroconversion illness sx
2-6 weeks after exposure, patients may experience a non-specific, flu-like illness. Features include:
Fever Muscle aches Malaise Lymphadenopathy Maculopapular rash Pharyngitis
Latent phase follows
List the sx of symptomatic HIV
After the latent phase
Weight loss
High temperatures
Diarrhoea
Frequent minor opportunistic infections, e.g. herpes zoster or candidiasis
AIDS defining illnesses
pnuemocystis jiroveci pnuemonia,
non-Hodgkin’s lymphoma,
TB.
Dg work up of HIV
ELISA
test for serum/salivary HIV antibodies and p24 antigen.
give reliable results 4-6 weeks after exposure.
Rx of HIV
Highly active antiretroviral therapy (HAART)
- does not cure HIV, but aims to reduce the viral load to undetectable levels in the serum.
- patient must keep taking the drugs for the rest of their lives. Non-adherence to HAART can result in resistance mutations which make treatment difficult or impossible.
Combination drugs classes combine to 1x/day tablets:
nucleoside reverse transcriptase inhibitors (NRTIs)
protease inhibitors (PIs)
non-nucleoside reverse transcriptase inhibitors (NNRTIs)
integrase strand transfer inhibitors (InSTIs)
Psychological support
Regular monitoring
POST EXPOSURE PROPHYLAXIS
Which regular tests are included in HIV monitoring
CD4 count HIV viral load FBC Urinalysis ALT, AST and bilirubin Patients may also require pregnancy testing, and in treatment failure, resistance testing.
What is post exposure prophylaxis
Rx for when a pt has as suspects exposure to the HIV within the last 72 hrs to lower the risk of becoming infected.
1 month course of
Truvada (one tablet daily) + Raltegravir (one tablet twice daily)
Can HIV be transmitted to the baby ?
Yes.
It can be transmitted in utero
Can be transmitted during delivery and transmitted during through breastfeeding.
How is HIV transmission to the baby prevented
Antenatal antiretroviral therapy during pregnancy and delivery
Avoidance of breastfeeding
Neonatal post-exposure prophylaxis
Can HIV mothers deliver transvaginally
yes if the serum load is undetectable in the mother
what is the risk of transission to the baby w/ and w/o rx
w/ rx adherance: <1%.
w/o rx: greater than 1 in 4
what is syphillis
exually transmitted infection caused by the spirochete gram-negative bacterium Treponema pallidum subspecies pallidum.
types of syphillis
Other subspecies of Treponemes are responsible for non-sexually transmitted diseases such as Bejel, a chronic skin and tissue disease, Yaws, a disease of the bones and joints, and Pinta, a skin disease. Unlike syphilis, these diseases are transmitted by any close contact (sexual or not) and do not pass from mother to fetus.
pathophys of syphillis
1)primary syphilis occurs when
-motile Treponema pallidum enters through a break in the skin or through intact mucous membranes.
The bacteria divide and an infectious hard ulcer (CHANCRE) subsequently forms at the site of contact after an incubation period of 2-3 weeks. This is the first stage of acquired symptomatic syphilis:.
If left untreated, T. pallidum can persist and cause systemic damage via OBLITERATING ARTERITIS
This is where endothelial cells of the vessels excessively proliferate causing the lumen of the vessels to become narrowed. This can then result in ischaemia at the tissues supplied by these arteries which leads to the symptoms associated with syphilis.
sx of syphillis classification
congenital
acquired : early (up to 2 years) / late
- assyx(latent)
- sxxx
1) primary
2) secondary
3) tertiary
dg of syphillis
Dark ground microscopy of chancre fluid- detects spirochaete in primary syphilis
PCR testing of swab from active lesion
Serology:
1) Treponemal tests – assess for exposure to treponemes necessarily syphilis)
- Treponemal ELISA (IgG/IgM) – remains positive for life
- TPPA or TPHA – remain positive for life
2) Non-treponemal tests:
- RPR/VDRL: rises in early disease; falling titres indicate successful treatment or progression to late disease. False positives can occur in inflammatory conditions or during pregnancy.
- Lumbar puncture: CSF antibody tests in neurosyphilis
rx of syphillis
Penicillin is the treatment of choice.
others
- avoid sexual contact of any kind, or exposure of other people to active lesions until the condition has been successfully treated
- Contact tracing (ppl recently contacted)
- Screening for other STIs
- Follow-up serology to determine response to treatment
what is Jarisch Herxheimer reaction!!!!
inflammatory response secondary to death of treponemes, and results in a flu-like illness within 24 hours of treatment
supportive measures suff
neuro/cardivascular syph: oral steroids
preg of syphillis
antenatal syphillis screening should be done as it can be transferred to the fetus causing
- miscarriage
- stillbirth
- pre-term labour
- Congenital syphilis
spread of syphillis
sexual transmission, the infection can also be transmitted from mother to fetus via the placenta (congenital syphilis) and through infected blood products.
rf of syphillis
Engaging in unprotected sex – especially with high risk partners.
Multiple sexual partners.
Men who have sex with men (MSM).
HIV infection.
primary syphillis
1) papule (slightly elevated lesion with no fluid) will appear before ulcerating into a CHANCRE at the site of inoculation
- a painless singular, hard and non-itchy ulcer
- typically develops 9-90 days post infection on a genital site e.g. penis, scrotum, anus, rectum, labia or cervix.
However, chancres may be atypical in that they can appear at other sites e.g. oral, be multiple and painful. Classically chancres
when does a chancre heal
heal within 3-10 weeks with or without symptoms but may persist during secondary syphilis.
when does Secondary syphilis occur
develops 3 months post infection
sx of Secondary syphilis
Skin rash – hands and soles of the feet (not usually itchy or painful)
Fever
Malaise
Arthralgia
Weight loss
Headaches
Condylomata lata- elevated plaques like warts at moist areas of skin e.g. inner thighs, anogenital region, axillae
Painless lymphadenopathy
Silvery-gray mucous membrane lesions – oral, pharyngeal, genital
what phase comes immediatley after secondary syphillis
LATENT PHASE comes after secondary phase
Tertiary syphilis
3 subtypes
gummatous syphilis,
neurosyphilis
cardiovascular syphilis
what is Gummatous syphilis
Granulomas can form in bone, skin, mucous membranes of the upper respiratory tract, mouth and viscera or connective tissue e.g. lung, liver, testis.
Patients at this stage are non-infectious.
what is Neurosyphilis
Tabes dorsalis
– ataxia, numb legs, absence of deep tendon reflexes, lightning pains,
loss of pain and temperature sensation,
skin and joint damage.
Dementia – cognitive impairment, mood alterations, psychosis.
Meningovascular complications
– cranial nerve palsies, stroke, cerebral gummas.
Argyll Robertson pupil
– pupil is constricted and unreactive to light, but reacts to accommodation.
what is Cardiovascular syphilis:
Aortic regurgitation due to aortic valvulitis (diastolic murmur), also aortic root dilatation.
Angina due to stenosis of the coronary ostia.
Dilation and calcification of the ascending aorta.
how do you treat syphillis in pts w/ peniccilin allergy
advise penicillin desensitisation
rx for early syph
Benzathine penicillin 2.4 MU IM single dose.
rx for late syph
Benzathine penicillin 2.4 MU IM 3 doses at weekly intervals
rx for neurosyphillis
Procaine penicillin or Benzylpenicillin
what is the presentation of Congenital syphillis
saddle nose, rashes, fever and failure to gain weight.
list the non treponemal tests
VDRL: rises in early disease; falling titres indicate successful treatment or progression to late disease. False positives can occur in inflammatory conditions or during pregnancy.
-Lumbar puncture: CSF antibody tests in neurosyphilis
what is the venereal disease research laboratory (VDRL) test
checks for the antibodies your body makes in response to antigens produced by cells damaged by the bacteria
What is a rapid plasma reagin (RPR) test?
detecting the nonspecific antibodies that your body produces while fighting the infection
what is the Treponema pallidum particle agglutination assay (TPPA test)
indirect agglutination assay used for detection and titration of antibodies against the causative agent of syphilis,
