University:
University of North Carolina at Chapel Hill
Course:
NURS 312 | Pharmacology
Academic year:

2020
Views:

186

Pages:

1
Author:

ilikemyicons0y5

8.2 – “Clean up on Aisle HHV HV--5”: CMV tre treatment atment (Ganciclovir, val valganciclovir, ganciclovir, cidofovir, fo foscarnet, scarnet, probenec probenecid) id) • CMV infection (Mega-lo Market) occurs predominantly in immunocompromised, notably HIV (CD4 < 50) (“50 items or less” – should be “fewer”) & organ transplant (organ counter). Classically presents with CMV retinitis with retinal hemorrhages and infiltrates (pizza box). • Shared adverse effects o Associated with bone marrow suppression (bone marrow tray). Usually managed with hematopoietic growth factor s. Should be monitored for hematologic suppression. Effects may be additive with other myelosuppressive agents, especially with Zidovudine (pregnant princess eating bone marrow). • Ganciclovir (cans only recycle bins) o Guanosine analog, like acyclovir. Has to be tri-phosphorylated, before incorporating into viral DNA & jamming DNApol (jammed DNA conveyor belt). ▪ First Ⓟ step converts to ganciclovir monophosphate with a virus encoded kinase (UL97) which enables CMV-infected cell specificity (Market employee labeling Ⓟ for virus encoded . ▪ Following steps done by cellular kinases (kids going crazy with label guns) ▪ Protein kinase mutations can cause resistance o Incorporation stops DNA synthesis • Valganciclovir (great value samples) o Prodrug of ganciclovir with increased oral bioavailability (lady with open mouth) o As effective as IV ganciclovir for CMV retinitis o Used for prophylaxis in bone marrow & organ transplant (organs on ice) o Same MOA as ganciclovir • Foscarnet (fast car with a net) o Does not require Ⓟ by viral kinase. Active against acyclovir or ganciclovir resistant HSV, VZV, CMV. o Directly inhibits viral DNApol (kid crashing into register); pyrophosphate analog that directly selectively inhibits the pyrophosphate binding site on viral DNApols (bypassing phosphorylating CMV worker) o Available IV o Adverse effects ▪ May induce renal insufficiency. Appears to be directly toxic to renal tubular cells (spilled kidney beans) ▪ Hypocalcemia (broken milk bottles) ▪ Hypomagnesemia (falling magnets) ▪ Hypokalemia (banana peels) ▪ Seizures may result from electrolyte disturbances (shaky lines) • Cidofovir (Cid the security guard) o Does not require viral kinase Ⓟ so effective against acyclovir or ganciclovir resistant HSV, VZV, CMV (Cid the security officer has Ⓟ tags). This is especially important in immunocompromised patients, as thymidine resistant strains of VZV are found almost exclusively in immunocompromised populations o Directly inhibits viral DNApol (directly stopping DNA belt shut off switch) o Adverse effects ▪ Nephrotoxic, → proteinuria, azotemia, metabolic acidosis (broken kidney-shaped bottles) ▪ Must be coadministered with probenecid (probation officer Cid); blocks tubular secretion of cidofovir, limiting renal toxicity (probation offer protecting). Also blocks excretion and increases plasma concentration of many different drugs, including penicillins, MTX, & NSAIDS (druggie cashier not touching kidney bottles).