HIV Flashcards
Stained for CD20 shows:
Stained for CD3 shows:
these signal:
B cells
T cells
signals antigen being presented with some high prevelance
p24 is positive:
Pneumocystis PNU
Pneumocystis Jirovecii fungal organism
eosinic frothy material filling the alveolar space
PCP
pneumocystic jirovecii cysts
What is the mechanism of action of Trimethoprim/sulfamethoxazole (TMP/SMX)?
Inhibit enzyme systems involved in synthesis of tetrahydrofolic acid (THF).
folic acid synthesis inhibitor
drug of choice for PCP
phases of HIV infection:
Three phases of HIV infection:
1.Acute phase = characterized by a high level of virus production and viremia; the symptoms are nonspecific – viral syndrome.
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2.Chronic phase = a smoldering, low-level HIV replication, predominantly in lymphoid tissues, which may last several years.
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3.Crisis phase = breakdown of host defenses, viral replication, and the symptoms of persistent fever, fatigue, weight loss, and diarrhea..
What is the significance of the CD4+ cell counts in this patient?
HIV infection is stratified into three clinical categories based on CD4+ count:
1.³ 500/µL = low probability of progression
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2.200 - 499/µL
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3.< 200/µL or rapidly falling = high probability of progression
How is the clinical pathology laboratory evaluation used to help diagnose HIV infection?
ELISA p24/HIV-1/2 antibody test
First-line test to assess whether the patient has an HIV infection
Excellent sensitivity and specificity (>99%); however, due to the gravity of the diagnosis, a confirmatory test is done.
Western blot
Confirms the presence of the HIV
Classic pattern of HIV positivity shows 9 bands
PCR amplification for HIV-1
1.HIV viral load
- Earliest marker
- 1 - 6 weeks after exposure
- High viral load is related to seroconversion symptoms
2.p24 antigen
- First HIV antigen
- 1 - 8 weeks after exposure
3.HIV antibody
- May be detected as early as 2 weeks
- At 4 weeks will detect 95% of infections
- >99.9% of people by 12 weeks
What percent of patients with AIDS have clinical evidence of neurologic dysfunction?
30 - 50% of patients with AIDS have neurologic impairment during the course of their illness
What is the cause of the patient’s progressive confusion during the terminal phase of his illness?
Many processes need to be considered in the differential diagnosis of altered mental status in this patient:
1.Opportunistic diseases INFECTION!!!!!
Viral: CMV, PML
Bacterial: tuberculosis, pyogenic bacterial infections
Fungal: cryptococcus, histoplasmosis, coccidioidomycosis
Parasitic: toxoplasmosis
- Neoplastic diseases: lymphoma
- Primary HIV-associated syndromes: HIV encephalitis
Kaposi’s Sarcoma spots
What are the common pathogens producing diarrhea in patients with AIDS?
Common diarrhea producing pathogens in AIDS include:
Mycobacterium avium-intracellulare
Cryptosporidium or Isosporidium
Cytomegalovirus (CMV)
Intestines with macrophages that are full of acid fast bacilli
Mycobacterium avium-intracellulare
Colon CMV infection, ulcerations
CMV reactivation in colon
How do CMV infections differ in immunocompetent versus immunosuppressed patients?
•Immunocompetent patients = viral syndrome resembling acute infectious mononucleosis
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•Immunosuppressed patient, whether acquired primarily or as a result of reactivation = disseminated, fulminant, and lethal disease with multiorgan involvement.
top shows pneumocystis in lung
bottom shows cytomegalovirus in his lung
CMV Retinitas (included with retinal hemorrage slide)
JC virus in brain cells (late stage aids)
Toxoplasmosis in microglial brain cells
perivascular lymphomatous infiltrate.
They are characteristically B-cell neoplasms associated with Epstein-Barr virus (EBV) reactivation
reactivated EBV slide:
Kaposi sarcoma
associated with the human herpes virus 8
HIV: three most common secondary neoplasms found in HIV patients, look for ______ and they will also have _____
kaposis sarcoma
or lymphoma
possible HPV reactivation
neurological deficiency
HIV surface adhesion proteins, gp120 binds to:
major capsid protein is _____
CD4 receptor
p24 (able to test early in infection)
HIV cell requires _____
CD4 T cell to be activated to begin replication of hiv genome
clinical phases of hiv?
1.Acute viral syndrome
–Infection of memory CD4+ T cells in mucosal lymphoid tissues
–Death of many infected cells
–Viremia dissemination and development of host immune responses
- Chronic phase (clinical latency)
–Usually asymptomatic
–Lymph nodes and the spleen are sites of continuous HIV replication and cell destruction
–Over a period of years, the continuous cycle of virus infection, T-cell death, and new infection leads to a steady decline in the number of CD4+ T cells in the lymphoid tissues and the circulation
3.Clinical AIDS
–Breakdown of host defense
–Serious opportunistic infections, secondary neoplasms, or clinical neurologic disease
2 most common opportunistic infections that AIDS patients present with:
most common fungal infection AIDS patients present with:
Also:
pneumocystis jirovecci
Candidiasis (Candida albicans)
Most common fungal infection AIDS
Heralds the transition to AIDS
Oropharyngitis, pneumonia, tracheo-esophagitis
Cryptococcosis (Cryptococcus neoformans)
Inhalation of infected soil
Seen in10% AIDS
CNS meningitis, pneumonia
Coccidioidomycosis (Coccidioides immitis)
“Valley Fever” Southwest US
Pneumonia or disseminated to skin
Histoplasmosis (Histoplasma capsulatum)
Pneumonia or disseminated
Most common Bacterial infection for AIDS
MAI
Mycobacterium Avium-cellulare
Neoplams found in AIDS patients
Kaposi’s HHV 8
Anal carcinoma
HPV reactivation
matastisizing through basement membrane
Malignant carcinoma
most common neurologic dysfunctions:
JC polyomavirus
