HIV associated conditions

Question 1

Classification of HIV

Answer 1

• Class A: ASx infection or acute 1o HIV infection
• Class B: Bacillary angiomatosis, thrush (oral candidiasis), oral hairy leukoplakia, shingles (>1 dermatome or recurrent)
• Class C: bacterial pneumonia (recurrent), candidiasis of bronchi/trachea/lungs, CMV infection, TB

Question 2

Oral hairy leukoplakia (B)

Answer 2

• Associated w/ EBV, lesions are ASx white patches on the lateral/inferior border of the tongue
• Cannot be scrapped off (as opposed to thrush)
• There is acanthosis (thickening of epidermis) and hyperkeratosis

Question 3

Bacillary epithelioid angiomatosis (B)

Answer 3

• Often confused w/ kaposi sarcoma
• Red papules due to proliferations of small blood vessels lined by plump endo cells
• Associated w/ cat scratch fever (bartonella)

Question 4

Pneumocystis jiroveci (formerly PCP, class C)

Answer 4

• Used to be most significant pathogen in AIDS pts, is a fungus
• Nonspecific PNA Sx, CXR shows diffuse interstitial infiltrates w/ solitary or multiple nodules
• Pulmonary alveoli filled w/ foamy pink material
• Cysts are ovoid or cup-shaped w/ thick walls
• Budding is never seen

Question 5

Other fungal infections in AIDS pts (C)

Answer 5

• Aspergillus is rare, tends to favor Tx pts over AIDS
• Cryptococcus: primarily affects lungs or brain (chronic meningitis), can disseminate
• Round, pleomorphic budding yeast w/ thick capsule, large clear zone around organism
• Can cause bronchoPNA or interstitial pattern
• Coccidioides: causes flu-like Sx, small granulomas in lungs/LNs
• Large non-budding spherules filled w/ endospores
• Candida: can be oral (B) or esophageal, trachea, pulmonary (C)

Question 6

Bacterial infections (C)

Answer 6

• TB is defining pathogen for AIDS, as are other mycobacterium (MAC: mycobacterium avium complex)
• MAC are related mycobacteria that are ubiquitously found
• Colonizes lungs but extra pulmonary infections are more important clinically
• Can cause TB-like syndrome in elderly

Question 7

Viral infections (C)

Answer 7

• Kaposi sarcoma due to HHV8
• CMV reactivation can cause PNA, GI involvement
• CMV looks like owl’s eyes due to nuclear inclusions
• PML: reactivation due to AIDS, mostly affects brain (gray-white junction demyelination)
• Can see lipid-laden macs and viral inclusions (large purple objects) in oligodendrocytes

Question 8

Tumors (C)

Answer 8

• Kaposi sarcoma: HHV8

- Lymphomas: mostly large B cell, also burkitts (associated w/ EBV)

Question 9

Degenerative states (C)

Answer 9

• HIV-associated dementia (HAD): loss of myelin, axonal damage and neuronal damage
• Can see microglial nodules, giant cells
• Lesions most common in white matter
• Sub cortical involvement can produce mental and motor loss