OPPORTUNISTIC ILLNESSES IN IMMUNOCOMPROMISED PATIENTS Flashcards
At what concentration CD4 cells does AIDS occur
< 200 / microliter
At what concentration CD4 cells is there generally not a risk for an AIDS defining opportunistic infection
> 500 / microliter
how are opportunistic illnesses suppressed in HIV and other immunocompromised patients
with antimicrobial prophylaxis
t or f? Opportunistic illnesses accounted for most of the complications associated with HIV infections
true
what bacteria causes tuberculosis either by primary infection or reactivation of a latent TB infection
M.tuberculosis
what patients have a higher progression rate from latent TB to active disease
HIV patients
what antibiotic class covers TB
rifamycins
What does rifamycins do to CYP450 that can decrease the plasma levels of the ART drugs
induces CYP450
what 2 drugs replace rifampin in HIV patients due to weaker CYP450 inducer
rifabutin and rifapentine
What 2 bacteria are found MAC infections. Which can disseminate and which stays in the lungs?
M. avium dissimantes
M.intracellulare stays in lungs
what is the pathogenesis of MAC infection
-disseminated diseases in AIDS patients is mediated by M.avium
-spreads systemically to organs
-M. intracellulare cause of pulmonary disease
how to cover MAC infection
clarithromycin or azithromycin + anti TB drugs
what are the 3 viral opportunistic infections covered
Cytomegalovirus
Progressive Multifocal Leukoencephalopathy
Kaposi Sarcoma
in AIDS patients, what is Cytomegalovirus usually due to
reactivation of latent infection (subacute)
CMV disease arises when what count drops
CD4
what is the primary manifestation of CMV
retinitis where a lesion occurs near or on the retina and can result in irreversible blindness
antiviral coverage for CMV
ganciclovir
valganciclovir
foscarnet
cidofovir
how does progressive multifocal leukoencephalopathy occur
Papovavirus JC (JCV) infects the GI tract and remains latent but gets reactivated in HIV patients
in PML what does JCV do to the brain
it destroys white matter of the brain
what causes Kaposi Sarcoma
HHV 8 that infects B cells and promotes growth preventing apoptosis which forms benign tumors (skin cancer)
what are the 3 fungal infections in opportunistic infections
Pneumocystis Pneumonia
Cryptococcosis
Candidiasis
what fungus causes Pneumocystis Pneumonia
Pneumocystis jirovecii pneumonia (PCP)
when does Pneumocystis jirovecii pneumonia (PCP) occur
-is normally suppressed by immune system via CD4 cells in healthy people
-in AIDS patients arises when immune system can no longer contain the latent organisms
how does Pneumocystis jirovecii pneumonia (PCP) cause damage to alveoli
it is a yeast like fungi able to colonize and grow in the alveoli
manifestation of pneumocystis pneumonia caused by Pneumocystis jirovecii pneumonia (PCP)
pneumonia (fluid in the lungs)
2 coverages for Pneumocystis pneumonia and their mechanism of action
Bactrim and trimetrexate (used with leucovorin to reduce drug toxicity) inhibits folic acid synthesis
pentamidine and atovaquone inhibit electron transport (respiration = ATP synthesis)
what drug is used in combo with bactrim and trimetrexate to reduce drug toxicity
leucovorin
what is an opportunistic yeast that causes cryptococcosis in HIV patients
Cryptococcus neoformans
how is Cryptococcus neoformans transmitted
aerosol inhalation that allows yeast spores to germinate in alveoli
what allows cryptococcus to disseminate into the bloodstream and CNS in AIDS patients
deficiency in CD4+ T cells
manifestations of cryptococcus
-meningoencephalitis
-pneumonia
-CNS disease that disseminates from the lungs causing CNS lesions (cryptococcoma)
3 coverages for cryptococcus
-amphotericin B
-Flucytosine (given with amphotericin B)
-Fluconazole
mechanism of action and ADR for amphotericin B
causes leaks in ergosterol-rich fungal membranes
*nephrotoxic
mechanism of action and ADR for flucytosine
disrupts nucleic acid synthesis
*bone marrow suppression
mechanism of action and ADR for fluconazole
inhibits ergosterol synthesis
*CYP3A4 inhibitor
what is the most frequent opportunistic infection occuring in nearly all AIDS patients that are not on antifungal prophylaxis
candidiasis
where does candida colonize
they are commensal yeasts of skin, genitals and GI tract
when does candidiasis occur
when CD4 cells are depleted and Candida can colonize mucocutaneous surface
manifestations of candidiasis
oropharyngeal and esophageal candidiasis
coverages for candidiasis
-azole antifungals (fluconazole = diflucan)
-echinocandins (caspofungin, micafungin)
what are protozoan opportunistic infections
-Toxoplasmosis
-cryptosporidiosis
-cystoisosporiasis
what causes toxoplasmosis
reactivation of latent tissue cysts of the intracellular protozoan toxoplasma gondii that arises when CD4 counts drop
manifestation of toxoplasmosis
CNS mass lesions
transmission of toxoplasmosis
contact with cat feces (pregnant woman should avoid litter box)
treatment for toxoplasmosis
-Pyrimethamine + sulfadiazine
-Bactrim
cryptosporidiosis is caused by what
protozoan GI pathogen Cryptosporidium
manifestation of cryptosporidiosis
chronic diarrhea disease in HIV patients
transmission of cryptosporidiosis and cystoisosporiasis
fecal-oral
waterborne
treatment for cryptosporidiosis
nitazoxanide
cystoisosporiasis is caused by what
GI protozoan Cystoisospora
coverage for cystoisosporiasis
Bactrim
HIV patients can develop malignant B cell cerebral lymphoma that often present tumors containing cancerous cells infected with what virus
Epstein Barr Virus (EBV)
aka HHV4
