Flashcards in HIV, Syphilis and STDs Deck (69)
What is HIV itself?
Retrovirus that uses reverse transcriptase for reverse transcription (turning RNA into DNA) to integrate material into host cell DNA and new virus is produced
What is responsible for AIDS?
What does HIV target?
T cells (particularly CD4 T cells the helpers)
Also infects B lymphocytes and macrophages
What are lymphocytes?
WBCs that defend against protozoa, fungi, some bacteria and viruses
Routes of HIV transmission
Sexual transmission (infected body fluids)
Injection drug use
Occupational injury (needlestick)
HIV mom to infant
(not just casual contact)
*receptive anal intercourse has highest risk of transmission
What is another name for primary HIV infection?
Acute HIV/ acute retroviral syndrome
What is acute HIV?
2-6 wks after exposure
Mono like or flu like illness (about 2 wks and resolves spontaneously)
Why is acute HIV missed?
Routine HIV Ab test is negative so miss it
Lab for acute HIV
HIV RNA (viral load( is measurable and usually extremely high >100,000
Common sxs of acute HIV
Fever, adenopathy, sore throat, rash and mucocutaneous ulcers, myalgia, arthralgia, HA, diarrhea, n/v
What does the rash look like in acute HIV?
Half of pts
Upper trunk, neck and face
Lab abnormalities in acute HIV
Elevated transaminases (LFTs)
When does clinical latency occur?
When immune system response to infection (acute illness resolves) and pt seroconverts!!! and becomes antibody positive
Viral load decreases to a set point
CD4 t cell count slowly declines
When do you see full symptomatic infection of HIV?
When immune system deteriorates:
-Lymphnodes and tissue damaged from burnt out
-Virus may mutate and become more pathogenic
-Body fails to keep up replacement of CD4
*viral load increases
All general sxs of HIV
Fever, night sweats, LAD, fatigue, arthralgias, weight loss, oral hairy leukoplakia or thrush, prolonged diarrhes, cervical dysplasia, skin disorders, Kaposis, ITP
Normal CD4 t cell count
What is the definition when HIV progresses to AIDS?
CD4 T cell count <200 cells/mcL
HIV and 1 of 27 AIDS defining conditions (regardless of T cell count)
Types of AIDS defining conditions
What is pneumocystic jiroveci pneumonia?
Common opportunistic infection associated with AIDS
Caused by airborne fungus pneumocystis jiroveci
Reactivated dormant infection
Presentation of pneumocystic jiroveci pneumonia
Nonspecific: fever, cough, SOB
May have severe hypoxemia (usually younger 20-30)
CXR shows diffuse or perihilar infiltrates
How to diagnose pneumocystic jiroveci pneumonia
Sputum sample: see elevated LDH in most
Tx for pneumocystic jiroveci pneumonia
Bactrim and supportive
What does toxoplasmosis cause?
Encephalitis (most common intracranial lesion in HIV pts)
What causes toxoplasmosis?
Single celled parasite toxoplasma gondii
How to get toxoplasmosis
Ingestion of cat feces, contaminated rw food or utensils
Immuncompetent doesn't usually have pts
Presentation of toxoplasmosis in HIV pt
HA, focal neurological deficits, seizures, AMS
Maybe retinits or pneumonitis
Imaging for toxoplasmosis
Multiple contrast enhancing lesions on brain CT or MRI
Also seropositive for toxoplasmosis
Mycobacterium avium complex
May cause pulm infection when immunocompetent
Found in soil or dust inhaled
Presentation of MAC
Systemic disease in HIV
Night sweats, weight loss, abd pain, diarrhea, anemia