Cesar J. Figueroa and Monika K. Shah
Overview
Understanding the complexity of infectious complications faced by oncologic pts & the changes in patterns of drug resistance is necessary to provide adequate anti-infective support.
Some Clinically Relevant Bacteria
Gram negatives: Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus spp, Serratia marcescens, Acinetobacter baumannii, Enterobacter cloacae, Citrobacter spp, Providencia spp, Legionella pneumophilia, & non-pneumophila spp.
Gram positives: MSSA, MRSA, Coagulase-negative Staphylococcus, Enterococcus faecalis/faecium, Streptococcus pneumoniae, Streptococcus viridans group, Group A & B Streptococcus, Listeria monocytogenes.
Anaerobes: Fusobacterium spp, Bacteroides spp, Clostridium spp, Lactobacillus.
Selected Clinical Syndromes and Antimicrobials of Choice
Agents with Anaerobic Coverage
MNZ, Clindamycin, Beta-lactam/Beta-lactamase inhibitor, Carbapenems
Monitoring of Selected Antibacterials
• Vancomycin: Trough serum conc. most accurate & practical for monitoring efficacy → obtain before 4th dose (steady-state): Recommended in pts w/renal fxn changes or those needing prolonged Tx courses (Am J Health Syst Pharm2009;66:82)
• Most antibacterials: Need dose-adjustment based on GFR, few exceptions need dose-adjustment for liver dysfunction (ie, Cftx, tigecycline)
• All Beta-lactams: Ability to induce seizures at ↑ conc.; neurotoxicity reported w/use of carbapenems → risk w/Imipenem ↓ w/careful attention to dosage (Antimicrob Agents Chemother 2011;55:4943)
• AG & Polymyxin have the greatest potential for renal tox & should be used & monitored carefully in pts w/pre-existent renal disease.
Some Clinically Relevant Fungi
Yeast: Candida → albicans & non-albicans (ie, glabrata, krusei, parapsilosis, tropicalis, dubliniensis, guillermondii); Cryptococcus, Trichosporon.
Mold: Aspergillus → fumigatus (most common), flavus, terreus, niger; Mucormycosis agents → Mucor, Rhizopus, Cunninghamella, Rhizomucor, etc.; Fusarium; & Dematiaceous molds.
Dimorphic: Histoplasma, Coccidioides, Blastomyces, Paracoccidioides.
Commonly Used Antifungals
• Candidemia: IV central-catheter removal & ophthalmologic exam are recommended in all cases of Candidemia.
• In non-neutropenic pts → use Fluconazole or an Echinocandin
• If mod to severely ill OR neutropenic → echinocandins are preferred. Voriconazole is an adequate alternative if mold coverage is desired (Clin Infect Dis 2009;48:503)
• Aspergillosis: Voriconazole preferred, alternative: Liposomal Ampho B, dosing schemes vary, though use at higher doses (ie, 10 mg/kg/d vs. 3 mg/kg/d), a/w higher tox but no additional clinical benefit (AMBILOAD Clin Infect Dis 2007;44:1289)
Selected Antivirals and Therapeutic Uses
