Give the opportunistic infections in HIV, their associated CD4 count, and prophylaxis
- Pneumocystis jiroveci: CD4 <200, TMP-SMX (Alt. Dapsone, Atovaquone, Pentamidine)
- Toxoplasma gondii: CD4 <100 and positive IgG. TMP-SMX (Alt. Dapsone + Pyrimethamine + Leucovorin)
- Histoplasma capsulatum: CD4 <150 and endemic area. Itraconazole
- Varicella Zoster: Close contact with chicken pox/shingles AND no prior hx of dz or negative Ab. VariZIG or IVIG within 4 days of exposure
Differentiate radiographic findings of Primary CNS Lymphoma (PCL) from Toxoplasma encephalitis
Both are ring-enhancing lesions with edema and mass effect
Features that suggest PCL: solitary lesions, lesions >4cm, involvement of corpus callosum, periventricular, or periependymal areas
Toxo commonly involves the basal ganglia
Give criteria for a complicated parapneumonic effusion and treatment
pH <7.2
Glucose <60
WBC >50,000
LDH >1000
Positive Gram stain
Needs chest tube
Give the induration cutoffs for TB skin test
> 5mm: HIC, contacts of pt with known TB, organ transplant recipients and other immunosuppressed persons
> 10mm: Recent immigrants (<5 years) from endemic areas, IV drug users, high risk setting residents/employees, higher risk conditions (diabetes, leukemia, ESRD)
> 15mm: Everyone else
