5. HIV-AIDS and Opportunistic Infection Flashcards
when should you consider prophylaxis treatment for pneumocystis jirovecii
CD4 < 200
or
Orophayngeal candidiasis (even w/ <300 CD4!)
or
prior bout of PCP
what vaccine is given to children that are HIV infected and older than 2 months
meningococcal conjugate vaccine (serogroup A, C, W, and Y)
what are lab findings for toxoplasmosis
*seen in pt w/ CD4 < 100*
T.gondii in CSF - but could be false neg!
(serologic tests NOT useful bc antibodies to T. gondii are prevalent in general population)
how is cryptococcal meningitis diagnosed
(+) latex agglutination test of serum that detects cyptococcal Ag (CRAG)
or (+) culture of spinal fluid for cryptococcus
Where does the tumor associated w/ HHV-8 spread?
=kaposi sarcoma
extracutaneous spread - oral cavity, GI tract and resp tract
what is the DDx if CD4 counts are <50
Mycobacterium-avium complex (MAC)
CMV
Primary CNS lymphoma
HIV
where is MAC markedly increased?
metropolitan areas bc homelessness
How will a pt with active TB and >350 CD4 count present?
how about with advanced immunodef?
present w/ similar findings as uninfected persons
w/ advanced immunodeficiency: lower & middle lobe, interstitial and miliary infiltrates w/ mediastinal adenopathy and extrapul involvement
what are symptoms for primary CNS lymphoma
mass lesion, HA,
neuropsychiatric symptoms: confusion/ disorientation
lateralizing signs: altered gait & balance, falls, focal deficits
seizures
onset days - weeks
what do the skin lesions for kaposi sarcoma look like?
where are they most often located?
=papular, ranging in size from several mm to cm in diameter
-most often LE, face (ESP NOSE), oral mucosa and genitalia
what is the cornerstone of diagnosis for PJP
chest radiograph
- diffuse/perihilar infiltrates
- normal CXR
- atypical infiltrates (viral pneumonia, micoplasma pneumonia)
- apical infiltrates (TB & aspiration pneumonia)
last 3 used to rule other Dx out
list the 5 major problems encountered in CMV (most likely to least) in immunocompromised pts
*retinitis*
colitis
esophageal ulceration
encephalitis
pneumonitis
(retinitis present as “cottage cheese and ketchup infiltrate” on fundoscope exam)
what is the most common cause of pul dz in HIV infected pt
community aquired pneumonia
(bacterial, mycobacterial and viral pneumonias)
recurrent = AIDs defining
DDx for >300 CD4 count
pneumococcal pneumonia
pulmonary TB
herpes zoster
oral candidiasis
vaginal candidiasis
fatigue
what are AIDS-defining illnesses?
opportunisitic infxns
- multiple/recurrent bacterial infxn
- PJP
- kaposi sarcoma
- lymphoma
- CMV infxn
- histoplasmosis
- coccidiodomycosis (disseminated/extrapul)
- crytococcosis, (extrapul)
- mycobacterium TB of any site
what is the sequence of lab findings completed for HIV?
and how do you test if your results are a false positive?
combined immunoassay for HIV Ab w/ a test for HIV p24 Ag (which is detectable a week before Ab in acute infection)
if (+) –> HIV 1/2 Ab differentiation immunoassay
if differentiation assay (-) –> HIV-1 nucleic acid amplification test (NAAT)
==>(+) w/ neg-Ab = acute HIV
==> (-) = false positive
what organisms cause the common GI problem found in HIV pts
=enterocolitis
bacteria : Campylobacter, salmonella, shigella
viruses: CMV, adenovirus
Protozoans: Cryptosporidium, entamoeba histolytica, giardia, isospora, microsporidia
How often should CD4 counts be checked
every 3-6 months
(esp pts taking antiretroviral treatment)
HIV mimics a variety of other medical illnesses
What should you add to your DDx is pt presents with neurological dz
conditions that cause mental status changes/neuropathy
alcoholism
liver dz,
kidney dysfxn,
thyroid dz,
Vit deficiency
what helps to obtain a definitive diagnosis for pneumocytosis in 50-80% of cases?
wright giemsa stain
direct fluorescence antibody (DFA) of sputum
bronchoclaveolar lavage: if sputum (-) but still suspect pneumonia (95% pts)
what are the PE findings for HIV
maybe completely normal, nonspecific or highly specific
specfic for HIV infxn:
- hairy leukoplakia of the tongue
- disseminated Kaposi sarcoma
- cutaneous bicillary angiomatosis
general LAD common in early infxn
what can be a cause of considerable morbidity in severely immunocompromised HIV infected individuals?
CMV
HIV mimics a variety of other medical illnesses…
what should you add to your DDx if pt presents w/ wt loss & fever
CA
chronic infxn (TB, endocarditis)
endocrine disease (hyperthryoidism)
what is the immunization recommendation for Streptococcus pneumoniae in pts with HIV
*NOTE* AVOID LIVE VACCINES
HIV mimics a variety of other medical illnesses
What should you add to your DDx is pt presents with diarrhea
infectious enterocolitis
antibiotic-associated colitis
IBD
mal-abs symptoms
which is more sensitive/specific for presenting pneumocystis pneumonia, LDH or serum B-glucan
serum B-glucan
LDH also elevated but specificity only 75%
what are the limitations for CD4 count?
diurnal variation
depression w/ intercurrent illness
intra-lab and interlab variability
what are symptoms associated w/ pneumocystis jirovicii
*most common opportunistic infxn associated w/ aids*
fever, cough, SOB
hypoxemia (if severe)
(imaging - pneumothoraces if hx of HIV)
how common is it for a child to contract HIV who is born from HIV infected mom
w/o maternal treatment & perinatal prophylaxis = 13-40%
What are the prophylaxis considerations for Pneumocystis jirovecii
trimethoprim-sulfamethoxazole (TMP-SMX)
- 1 DS daily PO or 1 SS daily PO
what can you NOT tell from CD4 counts
how actively HIV is replicating in body
level of viral replication & prognostic info (test w/ HIV viral load)
what is DDx if CD4 counts are < 300
oral hairy leukoplakia
thrush
fever
wt. loss
diarrhea
Rate the types of transmission risks from greatest to least
receptive anal > ilicit drug use
> needle stick w/ infect blood > insertive anal/ receptive vaginal
> insertive vaginal > blood transfusion (greatly decreased bc screening improved)
increased risk w/ inflammed/ulcerative mucosa
what organ system can be involved in AIDS-related KS
what are the symptoms and how can you diagnose this?
pulmonary
=SOB, fever, cough, hemoptysis or chest pain
-diagnose via bronchoscopy (CXR may show asymptomatic findings)
What category had the greatest number of cases globally
general poplulation!
what is the most widely used marker to provide prognostic info & help guide therapy?
absolute CD4 lymphocyte count
–> decreases in count –> increase riskof serious opportunistic infxn (next 3-5 years)
*trend is more imp than single determination
HIV mimics a variety of other medical illnesses
What should you add to your DDx is pt presents with pulmonary processes
acute & chronic lung infxns
and other causes of diffuse interstitial pulmonary infiltrates
what is the HPV vaccine recommendation
all pts 13-26 yrs of age
HPV vaccine; 3 doses
if tests show ______ the diagnosis of pneumocystis pneumona is very unlikely
(3 scenarios)
normal diffuse capacity of CO
high resolution CT scan of the chest shows NO interstital lung dz
CD4 >250 w/i 2 months prior to evaluation of resp symptoms
what is the DDx if CD4 counts are < 100
cryptococcal meningitis
esophageal candidiasis
toxoplasmosis
HIV
what should you include in a differential Dx w/ ring enhancing lesions present on contrast enhanced CT
Toxoplasma (will show surrouding edema)
CNS lymphoma,
fungal infxn,
cerebral TB
what is the DDx if CD4 counts are < 200
pneumocystis jirovecii pneumonia (PJP)
disseminated histoplasmosis
kaposi sarcoma
extrapul/miliary Tb
NHL
CNS lymphoma
*start considering HIV in DDx*
what is the immunization recommendation for Hep B, Hep A and Influenza virus in HIV pts?
*NOTE* - AVOID LIVE VACCINES
what is the epidemiology of HIV
age?
population?
1.1 mil teens and adults in US living w/ HIV
15% undiagnosed
age 13-24: most likely to not know they’re infected
gay/bisexual men most of new diagnoses
African-american men > hispanic/white
what is the most common space occupying lesion in HIV
what is this a common cause for
toxoplasmosis
=multiple subcortical lesions with a predilection for the basal ganglia
-common cause of focal encephalitis in pt w/ AIDS
what should pleural effusion make you think of..
bacterial pneumonia
TB
pleural kaposi
what is the relationship of primary CNS lymphoma to HIV
2nd MCC space occupying lesion in HIV
= single ring enhancing lesions (but could be multiple)
< 50 CD4 count & highly assocaited w/ EBV (seen w/ CSF PCR)
what are imaging findings for toxoplasmosis
unenhanced CT scan - multiple subcortical lesions w/ predilection for the basal ganglia
MRI more sensitive than contrast enhanced CT –> MRI show multiple ring-enhanced lesions w/ surrounding areas of edema
discuss the global impact of HIV
2017 =
- 8 million new cases; 36.9 million ppl around the worlds
- 7 mil pt recieve meds
940K died from AIDs related illness
Sub-saharan africa = heaviest burden of HIV and AIDS world wide (66% all new infxns)
