HIV Flashcards
(36 cards)
Luke, 23 years old, presents with severe anal pain for 1 week
SHx: has been working on a cruise ship for the past month
O/E: anus appears normal, too tender to insert proctoscope, tender inguinal LNs
DDx?
Anal fissure
Thrombosed external haemorrhoids
IBD confined to rectum
Herpes simplex
Important aspects of Hx to ascertain with suspected STI/HIV
When do you last have sex?
Male or female partners?
Any anal or vaginal sex without a condom?
Partners from poorer countries?
Have you ever injected yourself with drugs or steroids?
Luke had receptive anal sex, without condoms, with several men on the cruise
Last sex was 10/7 ago
Ix?
Mx?
Anal swab for PCR for herpes simplex, Neisseria gonorrhoeae, Chlamydia trachomatis
Throat swab for N. gonorrhoeae PCR
First pass urine for Chlamydia trachomatis PCR
Serology for syphilis, HIV and hepatitis A/B
Treat suspected sexually-acquired proctitis for herpes, gonorrhoea and chlamydia at initial consultation, rather than waiting for results
What is the most common pathway of HIV transmission in Australia?
Anal sex
What is prevalence of HIV in homosexual men with casual partners?
~10%
When else should we consider HIV?
Disease commonly occurring with HIV or transmitted together
Clinical scenarios when it is important to know someone is HIV negative (e.g. pregnancy)
List 5 classical opportunistic infections seen in AIDS
Cerebral toxoplasmosis CMV retinitis Cryptococcal meningitis Pneumocystis pneumonia Mycobacterium avium complex (MAC) infections
List 5 typical or severe skin or oral infections which may suggest the presence of HIV/AIDS
Shingles in a young person
Intra-oral warts, widespread facial warts, severe anogenital warts
Severe or widespread herpes simplex
Facial molluscum contagiosum
Oral candidiasis, oral hairy leukoplakia, necrotising gingivitis
What other infection may be seen in an AIDS patient?
TB
List 3 cancers more commonly seen in HIV?
Lymphomas
Kaposi’s sarcoma
Anal cancer
List 8 scenarios in which HIV should be considered as a diagnosis
Classical opportunistic infections
Atypical or severe skin or oral infections (esp if risk factors)
TB
Cancers
Unexplained weight loss (esp if risk factors)
Infections with the same risk factors as HIV
High-risk exposure, high-prevalence populations
When transmission can be prevented (e.g. pregnancy, organ or blood donation, needlestick injury)
List some infections which have the same risk factors for acquisition as HIV
Other STIs (e.g. syphilis, gonorrhoea, anal STI in men, STI acquired abroad) Hepatitis B or C
What tests can be used to assess for HIV Ab?
EIA
Western blot
List 4 key messages to give a newly-diagnosed HIV patient
You have HIV, not AIDS
HIV is readily treatable, with only moderately increased risk of some diseases or complications; you may outlive your doctor
It should not interfere with your future plans; you will need to schedule regular medical checks
Use condoms - may only require brief mention on day one, but safer sexual practices should be discussed in some detail when the patient is ready for this
Describe the pathophysiology and natural Hx of untreated HIV
HIV infects and destroys CD4+ immune cells (monocytes, macrophages, glial cells, CD4+ T lymphocytes)
Gradually CD4+ cells are depleted faster than they are produced
Cell-mediated immunity is weakened, affecting tumour surveillance and suppression of existing and new infections
In the earlier stages (CD4+ 200-500 cells/uL), patients are often asymptomatic or they may notice worse-than-usual skin or oral conditions e.g. tinea pedis, folliculitis, warts, genital herpes
AIDS-defining illnesses are rare at CD4+ counts >200 and more common
List 4 key questions to ask at time of HIV diagnosis
Have you donated blood/semen in the last year?
Are any sexual partners from the last year contactable? Could you call them and recommend a test?
Who can you talk to for support?
Ask about symptoms of seroconversion illness as this may give a clue to the duration of infection (e.g. fever, sore throat, rash, diarrhoea, LOW)
How long after transmission does the HIV Ab test convert from negative to positive?
3-5 weeks
When does HIV seroconversion illness occur?
Usually ~3-5 weeks after transmission (around same time the Ab test becomes positive; a good description of a seroconversion illness suggests infection occurred about a month previously)
What are the symptoms of HIV seroconversion illness? How severe is this illness?
Fever Sore throat Rash Diarrhoea LOW Can be severe enough to prompt presentation to hospital, often presumed to be flu or glandular fever
Luke has no recollection of seroconversion symptoms
You perform further tests and he returns for further discussion a few days later
How should Luke be assessed?
1) SHx: work, relationships, accommodation, mood, drug/alcohol/tobacco use
2) Sexual transmission risks (STI screening)
3) Check for co-infections e.g. TB (consider CXR, TB y-IFN assay), hep B and C (serology)
4) Examine for skin/mouth/anogenital infections, TB or cancers
5) Record weight
6) CD4+ T cell count
7) HIV viral load and genotype sequencing for drug-resistance mutations
What signs of infections or cancers may be seen on the skin, mouth or anogenital region in HIV patients?
Kaposi’s sarcoma (skin or palate)
LN enlargement
Anal cancer (mostly in gay men)
Cervical cancer (in women)
Describe the relationship between CD4+ T cell counts and immunosuppression in AIDS
>500 = normal 200-500 = mild immunosuppression
What factors should be taken into account when making a decision to initiate HIV treatment?
What is the safest option for Luke? (In terms of AIDS prevention, maximising chance of viral suppression and prevention of serious non-AIDS events)
Safest option for population (controlling risk of transmission to a known seronegative partner and/or casual partners)
Luke, 27 year old with known HIV, returns from travelling the world with a bit of a cough
Has a new teaching job
Sx: dyspnoea with speaking, LOW, cough
O/E: temperature 37.8, some scattered crackles and wheezes
Has not had blood tests for 18 months
DDx?
Which common AIDS pneumonia presents in this way?
Always consider causes NOT related to HIV e.g. asthma
Viral URTI
Pertussis
Bacterial pneumonia (more common in HIV; Pneumocystis jiroveci pneumonia is an AIDS pneumonia which presents in this way)
Pulmonary TB (more common in HIV)