Opportunistic Infections Flashcards
What OIs are likely between 350-250 CD4 cell counts?
Bacterial skin infections
Varicella Zoster
Kaposi’s sarcoma
What OIs are likely between 250-150 CD4 cell counts?
Oral Candiasis (~249)
Pneumocystis carinii pneumonia
Non-Hodgkin’s lymphoma
What OIs are likely between 150-50 CD4 counts?
Cryptococcal meningitis
Herpes simplex virus infections
What OIs are likely between 50-0 CD4 counts
CMV infections
Mycobacterium-avium complex
What is Carini pneumonia?
Organism with protozoal and fungal properties,
Classified as a fungus.
Part of normal colonization in the lungs.
Only immunocompromised are at risk for a disease.
What are the s/sx of Carini pneumonia?
Usually slow onset (days to weeks). Fever Fatigue Dyspnea Tachypnea Non-productive cough
What is the most common form of PCP?
Pneumonia
Oral thrush is a common co-infection
How do you diagnose PCP?
CXR
ABG
Sputum culture
What is the first line treatment for moderate-severe PCP?
Bactrim 15-20mg/kg/d IV in 3-4 doses x 21 days
Switch to PO after clinical improvement
What is the first line treatment for mild-moderate PCP?
Bactrim 15-20mg/kg/d PO in 3 divided doses or Bactrim DS 2 tabs TID x 21 days
When are adjuvant steroids prescribed in PCP?
Pts with severe PCP and PaO2 < 70.
Must be started within 72 hours of treatment
What is the steroid regimen for PCP?
Started within 72 hours of treatment.
Mortality rates and rates of respiratory failure are reduced.
If patient is unable to take PO, use IV methylprednisolone (75% of PO prednisone dose)
What is the prednisone dose in PCP?
40mg BID days 1-5, then 40mg QD days 6-10, then 20mg QD days 11-21
In what patients do we have primary prophylaxis of PCP?
CD4 < 200, or CD < 14%, or A hx of oropharyngeal candidiasis, or A hx of AIDS-defining illness, or CD4 > 200 but < 250 if CD4 cell count monitoring (e.q. q3months) is not possible
What is first line primary prophylaxis therapy for PCP?
Bactrim DS 1 tab QD
OR
Bactrim SS 1 tab QD
When do we d/c primary prophylaxis therapy for PCP?
Patients who have responded to HAART with an increase in CD4 count to >/= 200 for >/= 3 months
What is the difference between primary and secondary prophylaxis therapy for PCP?
None, same regimen and reasons to d/c
What is toxoplasmic encephalitis?
Toxoplasma gondii.
Intracellular parasite (protozoa).
Passed to humans from raw or undercooked meat and by contact with feces from infected cats.
What are the s/sx of toxoplasmic encephalitis?
CNS infection Typically assocaited with fever Seizures Focal neurological deficits Other sx associated with encephalitis
How do you diagnose toxoplasmic encephalitis?
Serological testing for Toxoplasma IgG
Neuroradiological scans (CT or MRIs)
Brain biopsy
What does IgG show?
Past infxn
What does IgM show?
Current infxn
When do we take a brain biopsy for toxoplasmic encephalitis?
Usually reserved for patients refractory to empiric therapy
What is the 1st line therapy for toxoplasmic encephalitis?
Sulfadiazine + pyrimethamine + leucovorin for >/= 6 weeks
What do we use if pyrimethamine is not available or delayed?
Bactrim 5mg/kg IV BID x 6 weeks
When do we use primary prophylaxis for toxoplasmic encephalitis?
CD4 < 100 and toxoplasma IgG +
When do we d/c primary prophylaxis for toxoplasmic encephalitis?
After response to HAART and CD4 > 200 x >/= 3 months
What is used for secondary prophylaxis of toxoplasmic encephalitis?
Sulfadiazine + pyrethamine + leucovorin
When do we d/c secondary prophylaxis for toxoplasmic encephalitis?
After completion of initial therapy, and CD4 > 200 on HAART >/= 6 months
What is Cryptococcus meningitis?
Cryptococcus neoformans.
Encapsulated yeast.
The most common life-threatening fungal infection in AIDs patients.
Organism is ubiquitous in the environment and found in soil.
Exposure to aged bird droppings may increase the risk of infection.
What are the s/sx of Cryptococcus meningitis?
Progressive development of fever and/or HA, neck stiffness, photophobia, CNS changes. Disseminated disease (skin, pulmonary) with cryptococcus is common.
What is the 1st line treatment for Cryptococcus meningitis?
Liposomal ampho B + 5-FU x at least 2 weeks.
Followed by fluconazole 400mg qd x 8 more weeks.
Then chronic suppression with fluconazole 200mg QD for at least 1 yr
What is the primary prophylaxis for Cryptococcus meningitis?
None recommended
What is the secondary prophylaxis for Cryptococcus meningitis?
Chronic suppression.
Fluconazole 200mg QD
When do we d/c secondary prophylaxis for Cryptococcus meningitis?
After completion of initial therapy, patients must be asymptomatic, and have a sustained increase in CD4 > 100 after HAART x at least 3 months after the 1st year
What does MAC/MAI stand for?
Mycobacterium avium complex/infection
What is MAC?
Comprised of mycobacterium avium and Mycobacterium intracellulare.
Ubiquitous in nature, commonly inhabiting soil and water.
Typically begins w/colonization of the intestinal or respiratory tracts after organism ingestion or inhalation, with subsequent development of localized infection and sometimes seeding of the blood.
What are the most common s/sx of MAC?
Typically a multiorgan system disease in AIDs patients Fever Night sweats Anorexia Weight
What are the common s/sx of MAC?
Diarrhea Abdominal pain Increased LFTs Anemia Neutropenia Thrombocytopenia
What are the less common s/sx of MAC?
Hepatomegaly
Splenomegaly
Lymphadenopathy
What are the ways to diagnose MAC?
Culture is gold standard, but some pts with - blood cx for MAC will have positive liver, bone marrow or lymph node biopsies, which would confirm the diagnosis.
Organism takes 2-6 weeks to grow.
Clinical improvement on empiric therapy also helps confirm a presumptive diagnosis.
What is the first line treatment for MAC?
Clarithromycin 500mg BID + ethamutol 15mg/kg/d
OR
When DDIs/intolerance precludes the use of clarithromycin, Azithromycin 500-600mg/d + EMB 15mg/kg/d
When do you d/c first line therapy for MAC?
Completion of at least 12 months of treatment, remain asymptomatic and have CD4 count > 100 for > 6 months on HAART, and negative cultures
Who should receive primary prophylaxis of MAC?
Pts with CD4 < 50
What is the primary prophylaxis therapy for MAC?
Azithromycin 1200mg qweek OR Clarithromycin 500mg BID OR Azithromycin 600mg twice weekly
When do you d/c primary prophylaxis of MAC?
CD4 > 100 for >/= 3 months
What is CMV?
Envoloped double-stranded DNA virus that is a member of the Herpesvirus family.
It can become latent within infected cells.
Transmission occurs through infected body fluids.
Where can CMV manifest?
Various different organ systems in immunocompromised hosts, but in AIDs pts - 2/3 of cases are CMV retinitis
May also manifest as sophagitis, colitis, or neurologic CMV
What may happen if CMV retinitis is not treated?
Rapidly progress to retinal necrosis and permanent blindness
WHat are the s/sx of CMV?
Visual changes
Flashes of light
Blurred vision
Blind sports (floaters)
How do you diagnose CMV?
Clinical diagnosis
Culture and antigen detection are the most sensitive methods for detecting CMV in histological samples
What is the 1st line therapy for CMV retinitis: for sight threatening lesions?
Intravitreal injections of ganciclovir or foscarnet for 14 doses over a period of 7-10 days
PLUS
Valganciclovir 900mg PO BID x 14-21 days, then once daily
What is the 1st line therapy for CMV retinitis: for small peripheral lesions?
Valganciclovir PO 900mg BID x 14-21 days, then once daily
What is the 1st line therapy for CMV esophagitis or colitis?
Ganciclovir IV x 21-42 days or until resolution of sx.
PO valganciclovir if PO absorption is adequate.
Maintenance therapy usually not necessary, but should be considered after relapses.
What is the 1st line therapy for CMV neurological disease (PROMPT initiation of treatment)?
Combination of ganciclovir IV + foscarnet IV to stabilize disease and maximize response, continue until symptomatic improvement.
Maintenance therapy with PO valganciclovir + IV foscarnet should be continued lifelong unless there is evidence of immune recovery.
What is secondary prophylaxis of CMV retinitis?
Suppression
Valganciclovir 900mg once daily
When do you d/c CMV therapy?
CD4 > 100 for >/= 3-6 months on HAART
When is primary prophylaxis of CMV considered?
Pts with CD4 < 50 and CMV IgG +
What is primary prophylaxis therapy for CMV?
Oral ganciclovir or valganciclovir
Why do we not use primary prophylaxis for CMV?
High cost
Toxicity
Development of resistance
How is primary prophylaxis monitored?
Fundascopic examinations by an opthalmologist
What are Bactrim’s ADR?
Rash SJS Photosensitivity Fever Leukopenia Thrombocytopenia GI Hepatitis High K
What is sulfadiazine’s ADRs?
Rash Fever Leukopenia Hepatitis N/V/D Crystalluria
What are pyrimethamine’s ADRs?
Bone marrow suppression (increasing leucovorin can help with bone marrow suppression)
Rash
Nausea
What are amphotericin’s ADRs?
Renal
Infusion rxns
Fever, Chills, Rigors (give APAP, diphenhydramine, hydrocortisone, meperidine)
Decreased K and Mg
Lipid formulations less likely to cause these
What are fluconazole’s ADRs?
GI
LFTs
What are clarithromycin’s ADRs?
GI
Taste disturbances
What are azithromycin’s ADRs?
GI
what are EMB’s ADRs?
Oculotoxicity: optic neuritis and loss of red-green color perception; loss of cisual acuity
USE smaller doses of 15 mg/kg/d to avoid
What are ganciclovir/valganciclovir’s ADRs?
Bone marrow suppression (esp neutropenia)
GI
LFTs
What is 5-FC’s ADRs?
Bone marrow suppression
Renal
GI
