HIV Flashcards
CNS mass lesion in HIV pts - causes
Common - toxo * - tuberculoma - lymphoma Less common - cryptococcoma - PML - bacterial abscess - other (syphilis, tumor, Chagas, Nocardia, Aspergillus)
Focal lesions on CXR
TB
fungal
bacterial
nocardia
Meningitis in HIV pts - causes
cryptococcus TB syphilis bacterial - strep, listeria viral fungal lymphoma
5 min neuro screen:
pain in feet, decreased DTRs
sensory neuropathy (‘d’ drugs)
cells infected by HIV
CD4 T cells
macrophages
dendritic cells
5 min neuro screen:
cauda equina syndrome
CMV radiculitis
CXR in HIV
normal - PCP, TB, fungal, bronchitis
Diffuse infiltrates - PCP, TB, fungal, KS, CMV, LIP
Focal airspace - TB, fungal, bacterial, nocardia
PTx - PCP
Nodules/cavities - TB, fungus, staph, nocardia, rhodococcus, KS, endocarditis
Adenopathy - TB, fungus, MAC, lymphoma
Pleural effusion - TB, bacterial, KS, lymphoma, uremia, CHF, hypoalbuminaemia
Diffuse infiltrates on CXR
PCP TB fungal KS CMV LIP
Rx cerebral toxo
pyrimithemine + sulfadiazine (+ folinic acid)
alt clind+pyrimeth, high dose TMP/SMX, dapsone, atovaquone
Nevirapine risk and RFs for it
hypersensitivity rxn (rash, hepatotoxicity) - esp men with CD4>400, women CD4>250
Spectrum of HAND (HIV-associated neurocognitive disorder)
ANI - asympt neurocog impairment
MND - minor neurocog disorder
HAD - HIV-associated dementia
preferred TB PI
efavirenz
ICP elevation
crypto
PTx on CXR
PCP
problem with abacavir (ABC) and how to prevent
hypersensitivity rxn 3-7% - mortality
predict with HLA-B5701 test
most common cause of retinitis in AIDS
CMV
Acute HIV infection - time after
3-10 weeks
Leukopenia in HIV - frequency
- causes
50% patients with advanced disease Due to HIV Drugs - AZT, cotrim, sulfas, pyrimethamine, ganciclovir, ABx Infections - MAC, TB, fungi, parvo B19 Malignancies, myelodysplasia
NNRTI features
long half-life 2-3 wks
lots of drug interxns
not active vs HIV-2 or group O
risk resistance
Indications for TMP/SMX prophylaxis of toxo/PCP
CD4 not available - WHO stages 2,3,4 CD4 available - CD4<350 (LMIC) - WHO stages 3,4 Alt - all PLHIV
risks of starting ARV at low CD4
higher risk OI
higher risk toxicity
non-AIDS related complications more common (CVD, Ca, liver, renal disease)
3 I’s for HIV/TB
Intensified case finding for active TB
Infection control for TB at all clinical encounters
INH preventive treatment - latent TB prevalence >30%
- all with documented latent TB
preferred PI in pregnancy
lopinavir/ritonavir
Hepatobiliary disorders in HIV
Viral hepatitis OIs - MAC, TB, bartonella, endemic fungi Malignancies Drugs - HAART, anti-TB, ABx, statins, psy Cholangitis - MAC, crypto, microsp, CMV
Diarrhoea etiology in HIV
TB MAC bacteria (salmonella, shigella, E coli, SI bact overgrowth) protozoa (crypto, isospora belli, microsporidium, giardia, cyclospora, E histolytica, strongyloides) fungi (histoplasmosis) virus (CMV, HSV) HIV (AIDS enteropathy) malignancies (KS, lymphoma) drugs (PIs, ABx)
Radiologic characteristics of CNS masses in HIV
Enhancement with contrast - toxo (ring enhancing) - lymphoma (ring or diffuse enhancement) - tuberculoma (diffuse enhancement) Non enhancing - crypto -PML # lesions - toxo (multiple) - lymphoma (single / multiple) - tuberculoma (single / multiple)
Lactic acidosis Sx
A, N, V, AP pancreatitis, hepatitis SOB, arrhyth multi-organ failure, death = increased anion gap + lactate
Etiologies if small volume diarrhoea
colitis / proctocolitis - tenesmus, bld, mucus
- shigella
- campylobacter
- C diff
- HSV
- CMV
Clinical manifestations of CD4 <100
can be asympt Fungal candida oesophagitis Cryptococcus Viral disseminated CMV Bact disseminated MAC Parasite toxo Microsporidiosis Chronic cryptosporidiosis Ca CNS lymphoma
ARVs to avoid in TB
PIs - interxn with rifampicin
NVP - use EFV instead (can use if needed)
Lactic acidosis RFs
female older age high BMI - esp d4T, ddI, combination + - esp 1st 3/12 Rx
Benefits of ART
prevent OI, Ca Alter/reverse course of existing OIs Improve/preserve immune ftn ↓ Sx ↑ QOL Restore hope ↓ transmission
Pleural effusion on CXR
TB bacterial KS lymphoma uraemia CHF hypoalbuminemia
Common lung disease aetiologies in HIV
TB
PCP (pneumocystis jiroveci)
bacterial
fungal
AIDS definition
CD4<14%
AIDs defining illnesses (opportunistic infections)
Commonest cause of bacterial pneumonia in HIV
pneumococcus (100x increased risk)
Why is CVD more common in HIV?
HIV - dyslipidemia - endothelial damage - vascular dysftn - chronic inflammation - procoagulant factors - lipodystrophy ART - dyslipidemia - endothelial dysftn - HT - insulin R - fibrinogen levels - lipodystrophy
AIDS-defining cancers
Kaposi’s sarcoma
Primary CNS lymphoma
NHL
invasive Cx Ca
Etiologies if large volume diarrhoea
small bowel disease
- cryptosporidium
- microsporidium
- cystoisospora
- giardia
seizures, focal deficits
toxo
Potential reasons for non infectious complications of HIV
chronic immune system stimulation chronic inflammation premature aging mitochondrial damage (esp d drugs, NRTIs) drug toxicity
Thrombocytopenia in HIV - frequency
- causes
40% patients - may be early sign of HIV
Periph destruction due to autoantibodies
- HIV, drugs
BM probs - infections, malignancy
Cancers with increased incidence in HIV (not dependent on CD4)
liver cancer Hodgkin's disease anal cancer melanoma oropharyngeal cancer lung cancer
Lactic acidosis management
- obtain venous sample w/o tourniquet
- stop ARV if symptomatic + high lactate
- supportive Rx
- no d4T, ddI or AZT in next regimen
- routine monitoring not required
Treatment failure WHO definition
Clinical - new/recurrent stage 4 condition (IRIS excluded)
Immunological - fall of CD4 to baseline / 50% from peak
Virological - VL >5000
Oesophageal disease in HIV
- aetiology
- sx
- management
candida CMV HSV TB fungi cancer idiopathic - CD4 <100 - dysphagia / odynophagia, CP - empiric Rx candida (fluconazole 100-200mg 2/wks); EGD & Bx if no response
NRTI class toxicities
mitochondrial toxicity - neuropathy, LA lipodystrophy myopathy hepatitis pancreatitis hyperlipidaemia
Cause of Kaposi’s sarcoma
Human herpesvirus 8
Dyslipidaemia in HIV - causes
HIV
ARVs - esp boosted PIs, also NRTIs, efavirenz
AIDS-associated cancers (not AIDS-defining)
primary effusion lymphoma
SCC conjunctiva
subacute progressive deficits
PML
Clinical manifestations of CD4 100-200
can be asympt Resp PCP Histoplasmosis / coccidiomycosis Military/extrapulm TB Cardiomyopathy Neuro neuropathies / myelopathy Dementia PML Other wasting NHL
Adenopathy on CXR
TB
fungal
MAC
lymphoma
CMV retinitis lesions
2/3 unilateral
‘cheese and ketchup’
uveitis rare
5 min neuro screen:
strength ok but slow mentation
HIV dementia
Anaemia in HIV - frequency
- causes
70-80% patients with advanced disease Anaemia of chronic disease Drugs - AZT, cotrim, dapsone, primaquine Infections - parvo B19, fungi, TB Nutritional - iron, folate, B12, scurvy, Cu Malignancies, myelodysplasia
HIV important glycoproteins and their function
gp120 - binds CD4 receptor and co-receptor (CXCR4 or CCR5)
gp41 - promotes fusion of viral and cellular membranes
NRTIs active against hep B
lamivudine 3TC
tenofovir TDF
NRTI - least to most toxic (roughly)
Lamivudine 3TC Emtricitabine FTC Tenofovir TDF Abacavir ABC Zidovudine AZT Didanosine ddI Stavudine d4T