HIV-AIDs Flashcards
(29 cards)
How is HIV infection and AID transmission?
Virus is passed through sexual contact, through transfusion of contaminated blood or blood products, through sharing of contaminated needles and syringes among infection drug users; intrapartum or perinatally from mother to infant or via react milk
—HIV-1, HIV-2
What is the is pathophysiology and Immunopathogenesis of HIV?
Profound immunodeficiency resulting from a progressive quantitative and qualitative deficiency of the subset T lymphocytes refereed to as helper T cells (CD4+)- primary cellular receptor for HIV
—Co-receptors CCR5 and CXCR4
Describe the primary infection of HIV?
Virus infects CD4+ cell, GALT
—viremic stage during primary infection
—some pt= “acute retroviral syndrome” a mononucleosis-like illness
—disseminating virus to lymphoid and other organs throughout the body
Describe the chronic and persistent infection of HIV?
Chronic infection develops that persists for a median time of 10 yrs before the untreated pt becomes clinically ill
-decreasing number of T cells
-active viral replication can almost always be detected by as plasma viremia and the demonstration of virus replication in lymphoid tissue
-steady-state viremia (viral set point_ at 6 months to 1 year postinfection has important prognostic implication for the progression of HIV disease
—low viral set point at 6-1yr after infection progress to AIDs more closely
Describe advanced HIV disease?
The presence of a CD4+ T cell count of <200/mL or an AIDS-defining opportunistic disease establishes a diagnosis of AIDS
Clinical finding on the acute HIV syndrome
General: fever, pharyngitis, lymphadenopathy, headache/retroorbital pain, arthralgia/myalgia, lethargy/malaise, anorexia/wt loss, N/V/D
Neurological: meningitis, encephalitis, periperal neuropathy, myelopathy
Dermatological: erythmatous maculopapular rash, mucocutaneous ulceration
What are the most common secondary infection disease of HIV?
P. Jiroveci, CMV, Candida albicans, M. Avium intracellular, M. Tuberculosis, cryptococus neoformans, Toxopalsma gondii, HSV, cryptosporidium, isospora belli (diarrhea) , JC virus (PML)
RX for HIV infection?
- Two NRTIs +integrate inhibitors
- Two NRTIs + protease inhibitors
- Two NRTIs and NNRTIs
What should you expect from HIV treated?
1-log re-education in plasma HIV RNA within 1-2 months
Decline in plasma HIV RNA < 50 copies/mL
Rise in CD$+ T cell count 100-150/mL during the first year
How to prepare for secondary infection when infected with HIV?
T cell <200: P. Jiroveci
T cell < 50: M. Tuberculosis
Vaccination with the influenza and pneumococcal polysaccharide vaccines is generally recommended for all pt
Testing for HIV?
- Viral load- for initial detection prior to seroconversion, also used with HAART therapy. Used to detect replicating virus
- ELISA for HIV antibody- gold standard screening Test
- Western Blot- gold standard confirmatory test after ELISA
- Absolute CD 4 count-prognostic indicators and progress of HIV->AIDS
What is the CDC Recommendation for Clinical practice regarding HIVs?
All adults ages 13-64 should be screened at least once in their lifetimes
—Rapid HIV screen (search’s for p24 Ag)- still requires confirmatory testing
—results in 10-20 minutes
—Pretest counseling should be given
What opportunistic infection should you consider when the CD4 cell count in >250?
Bacterial infections Tuberculosis Herpes simplex Herpes zoster Vaginal candidiasis Hairy leukoplakia Kaposi sarcoma
What opportunistic infection should you consider when the CD4 cell count in less than 200 but greater than 50?
Pneumocystis Toxoplasmosis Cryptococcosis Coccidioidomycosis Cryptosporidiosis
What opportunistic infection should you consider when the CD4 cell count in <50?
Disseminated MAC infection
Histoplasmosis
CMV retinitis
CNS lymphoma
Describe Cryptosporidium?
Protozoan that infects intestinal epithelial cells
Sx: Abdominal cramps/pain
Major cause of chronic diarrhea in HIV/AIDs up to 3-17 l of stool a day
Describe D. Latum?
Helminth (fish tapeworm)
Acquired: eating larva in raw or undercooked fish
Sx: hardly any Sx. B12 deficiency (megaloblastic anemia)
Detection: identification of eggs in feces
Describe Mycobacterium Avium Intracellulare Complex?
Non-tuberculous mycobacterium (NTM) infection comprised of M. Avium and m.intracellulare
CXR: fibrocaitary with bronchiectasis, does not have dominant apical involvement like TB
Seen most commonly with a CD4 below 50- disseminated readily
Sx: insidious >5 wks: cough, weight loss, fever, lethargy, diarrhea
Hemoptysis rare
Prophylaxis: azithromycin
Describe Progressive Multifocal Leukoenxephalopathy?
Cause: JC polyomavirus
Sever Demyelinating disorder of the CNS-affects white matter but has cortical extension
Seen in AIDs with less than 200 CD4 counts
MRI: extensive damage to white matter tracks with cortical involvement
Dx: brain biopsy is gold standard
—PCR for JC virus with CSF
Describe CNS Lymphoma?
Originates from EBV- typically B cell in nature
Sx: Mitch like many space occupying lesions in the CNS-focal neurological deficits, ocular deficits increase intracranial pressure (look for papilledema), HA, carnival, neuropathic, and can have seizures
CT/MRIS findings: solitary, well defined mass, necrosis, location can include brain, meninges, SC, etc
Incredible response to IV steroids ( can shrink within days)
Dx: extensive, testing CSF for EBV
Describe Cryptococcus neoformans?
Encapsulated fungi (can be G+ gram stain with surrounding halo on INdia Ink stain)
CD4 less than 100
Acquire from bird dropping
Sx: altered mental status, fever, malaise, HA
—1/3 pts have meningeal signs, unchallenged rigidity, photophobia , Messi
—Dx: serum cryptococcal Ag, get a CSF to stain with India Ink
__Tx: fluconazole. If severe, liposomal AmphoB
Describe Toxoplamsa Gondii?
Protozoan- obligate, intracellular Seen when CD4 count is < 100 Prophylaxis- TMP-SMX Acquired: cats and eating infected meat SX: HA, confusion, fever neurologic complaints CT/MRIs-ring enhancing lesions Dx: serum IgG, brain bx
Describe HSV encephalitis?
HSV-1 reactivation- dsDNA, tegumented, icosahedral virus
Sx: rapid onset of HA, fever, neurodeficits, impaired consciousness
MRI: temporal lobe involvement
Dx: HSV PCR from CSF
Rx: IV acyclovir
Describe Candida Albicans?
Yeast-with KOH prep generally always have pseudohyphae
Causes: thrush, esophagitis, vulvogaginitis, skin infections
** easily scraped off tongue
