Antibiotics for UTI (Staudinger) Flashcards
What are common causes of adult male UTIs?
Prostatitis, Epididymitis, Orchitis, Pyelonephritis, Cystitis, Urethritis, Urinary catheters
Why is Imipenem and Cilastatin commonly used in combination to treat male UTIs?
Imipenem is a carbapenem which is a cell wall synthesis inhibitor. Cilastatin is a renal peptidase inhibitor.
DHP-1 enzyme found in the kidney rapidly degrades imipenem. Cilastatin combined with IV imipenem protects it from degradation.
What are the first line drugs commonly recommended for simple UTIs in males?
Cephalexin
Ceftriaxone
Ampicillin
Amoxicillin
Trimethoprim/Sulfamethoxazole
Fosfomycin
Nitrofurantoin
Cephalexin
1st generation cephalosporin (cell wall synthesis inhibitor) used to treat simple UTIs in males
Ceftriaxone
3rd generation cephalosporin (cell wall synthesis inhibitor) used to treat simple UTIs in males
What are the two main advantages of cephalosporins compared to penicillins when treating simple UTIs in males?
- they are more resistant to beta-lactamases
- the new R group adds chemical versatility for future development of new antibiotics
Ampicillin and Amoxicillin
Aminopenicillins (broad spectrum) cell wall synthesis inhibitors used to treat simple UTIs in males
MOA of Trimethoprim/Sulfamethoxazole
They are folic acid synthesis inhibitors. Sulfanamides block the first step (production of dihydropteroic acid) and trimethoprim blocks the last step (production of tetrahydrofolic acid).
What organisms does Trimethoprim/Sulfamethoxazole cover?
many gram-negative and gram-positive bacteria, but NO anaerobic coverage, some protozoan coverage
What are the warnings of Trimethoprim/Sulfamethoxazole usage?
Serious liver problems
Serious hypoglycemia (low blood sugar)
Pregnancy (fetal harm)
Serious skin reactions
Kernicterus in neonates
What organism accounts for 80% of simple (uncomplicated) UTIs in males?
E. coli (usually resistant to ampicillin, trimethoprim and fluoroquinolones)
Nitrofurantoin
First choice agent for simple (uncomplicated) UTIs in males. Resistance to nitrofurantoin is RARE; watch for adverse effects in older patients.
MOA- Damages bacterial DNA (the reduced form is highly reactive) creates multiple reactive intermediates that attack macromolecules within the cell.
MOA of Nitrofurantoin
Damages bacterial DNA (the reduced form is highly reactive) creates multiple reactive intermediates that attack macromolecules within the cell.
Multiple MOAs is likely responsible for the low development of bacterial resistance.
What is the first choice agent for simple (uncomplicated) UTIs in males due to resistance issues?
Nitrofurantoin. First choice agent for simple (uncomplicated) UTIs in males. Resistance to nitrofurantoin is RARE; watch for adverse effects in older patients.
When is nitrofurantoin contraindicated?
In patients with known G6PD deficiency (hemolytic anemia) and in patients with chronic renal insufficiency
Fosfomycin
MOA binds covalently (Cys-115) and deactivates bacterial MurA enzyme. The first step of bacterial cell wall synthesis is disrupted. Reduces bacterial adhesion in the urinary epithelial cells.
What agents are recommended for severe UTIs in males?
Fluoroquinolones such as Ciprofloxacin and Levofloxacin (not recommended for simple UTIs)
What agents are recommended for complicated UTI or kidney infections?
Fluoroquinolones such as Ciprofloxacin and Levofloxacin (not recommended for simple UTIs)
Balanitis
inflammation of the glans penis. Commonly caused by Candida spp. Treated with Clotrimazole, Miconazole or Nystatin for allergy or sensitivity to imidazole compounds.
What agent is used for balanitis if anaerobes are the causative agents?
Metronidazole
Amoxacillin/Clavulanate (Augmentin)
What agent is used for balanitis if staph or strep are the causative agents?
Mupirocin (Bactroban) - topical antibiotic in the carboxylic acid class that works by blocking a bacteria’s ability to make protein
What agents are used in a more severe case of balanitis?
Cephalexin
Clindamycin
