HIV

Question 1

Stained for CD20 shows:

Stained for CD3 shows:

these signal:

Answer 1

B cells

T cells

signals antigen being presented with some high prevelance

Question 2

Answer 2

p24 is positive:

Pneumocystis PNU

Question 3

Answer 3

Pneumocystis Jirovecii fungal organism

eosinic frothy material filling the alveolar space

PCP

Question 4

Answer 4

pneumocystic jirovecii cysts

Question 5

What is the mechanism of action of Trimethoprim/sulfamethoxazole (TMP/SMX)?

Answer 5

Inhibit enzyme systems involved in synthesis of tetrahydrofolic acid (THF).

folic acid synthesis inhibitor

drug of choice for PCP

Question 6

phases of HIV infection:

Answer 6

Three phases of HIV infection:

1.Acute phase = characterized by a high level of virus production and viremia; the symptoms are nonspecific – viral syndrome.

●

2.Chronic phase = a smoldering, low-level HIV replication, predominantly in lymphoid tissues, which may last several years.

●

3.Crisis phase = breakdown of host defenses, viral replication, and the symptoms of persistent fever, fatigue, weight loss, and diarrhea..

Question 7

What is the significance of the CD4+ cell counts in this patient?

Answer 7

HIV infection is stratified into three clinical categories based on CD4+ count:

1.³ 500/µL = low probability of progression

●

2.200 - 499/µL

●

3.< 200/µL or rapidly falling = high probability of progression

Question 8

How is the clinical pathology laboratory evaluation used to help diagnose HIV infection?

Answer 8

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

Question 9

What percent of patients with AIDS have clinical evidence of neurologic dysfunction?

Answer 9

30 - 50% of patients with AIDS have neurologic impairment during the course of their illness

Question 10

What is the cause of the patient’s progressive confusion during the terminal phase of his illness?

Answer 10

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

2. Neoplastic diseases: lymphoma
3. Primary HIV-associated syndromes: HIV encephalitis

Question 11

Answer 11

Kaposi’s Sarcoma spots

Question 12

What are the common pathogens producing diarrhea in patients with AIDS?

Answer 12

Common diarrhea producing pathogens in AIDS include:

Mycobacterium avium-intracellulare

Cryptosporidium or Isosporidium

Cytomegalovirus (CMV)

Question 13

Answer 13

Intestines with macrophages that are full of acid fast bacilli

Mycobacterium avium-intracellulare

Question 14

Answer 14

Colon CMV infection, ulcerations

Question 15

Answer 15

CMV reactivation in colon

Question 16

How do CMV infections differ in immunocompetent versus immunosuppressed patients?

Answer 16

•Immunocompetent patients = viral syndrome resembling acute infectious mononucleosis

•

•Immunosuppressed patient, whether acquired primarily or as a result of reactivation = disseminated, fulminant, and lethal disease with multiorgan involvement.

Question 17

Answer 17

top shows pneumocystis in lung

bottom shows cytomegalovirus in his lung

Question 18

Answer 18

CMV Retinitas (included with retinal hemorrage slide)

Question 19

Answer 19

JC virus in brain cells (late stage aids)

Question 20

Answer 20

Toxoplasmosis in microglial brain cells

Question 21

Answer 21

perivascular lymphomatous infiltrate.

They are characteristically B-cell neoplasms associated with Epstein-Barr virus (EBV) reactivation

Question 22

reactivated EBV slide:

Answer 22

Question 23

Answer 23

Kaposi sarcoma

associated with the human herpes virus 8

Question 24

HIV: three most common secondary neoplasms found in HIV patients, look for ______ and they will also have _____

Answer 24

kaposis sarcoma

or lymphoma

possible HPV reactivation

neurological deficiency

Question 25

HIV surface adhesion proteins, gp120 binds to:

major capsid protein is _____

Answer 25

CD4 receptor

p24 (able to test early in infection)

Question 26

HIV cell requires _____

Answer 26

CD4 T cell to be activated to begin replication of hiv genome

Question 27

clinical phases of hiv?

Answer 27

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

2. 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

Question 28

2 most common opportunistic infections that AIDS patients present with:

Answer 28

Question 29

most common fungal infection AIDS patients present with:

Also:

Answer 29

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

Question 30

Most common Bacterial infection for AIDS

Answer 30

MAI

Mycobacterium Avium-cellulare

Question 31

Neoplams found in AIDS patients

Answer 31

Kaposi’s HHV 8

Question 32

Answer 32

Anal carcinoma

HPV reactivation

matastisizing through basement membrane

Malignant carcinoma

Question 33

most common neurologic dysfunctions:

Answer 33

JC polyomavirus