Prostatitis

• Resistant organism more likely if recent urological intervention, ciprofloxacin use or travel. Consult Infectious Diseases/Clinical Microbiology if known to be an ESBL producer or previously cultured resistant organisms.
• Consider sexually transmitted cause of infection.
• Urine cultures should guide antimicrobial choice and should be repeated at one week to confirm sterility.
• Nitrofurantoin is not appropriate for treatment of prostatitis due to poor tissue penetration.

Pathogens

• Common: E. coli (up to 90%), Proteus spp., Klebsiella spp., Pseudomonas spp.
• Other: Anerobes, enterococci

Drug Treatment

• Duration:
  • 4 weeks (spontaneous)
  • 4 weeks minimum (complicated)
  • Aim for early PO switch

Empiric

Spontaneous (no prior intervention)

trimethoprim+sulfamethoxazole HMLSchedNZFPMLnoids Trimethoprim+Sulfamethoxazole F: 0.8 Half life: 9 hours / 12 hours Elimination: CYP2C8/9 acetylated fe: 0.3 / 0.7 (co-trimoxazole)

PO 160 mg/800 mg twice a day

• fe (trimethoprim) = 0.7, fe (sulfamethoxazole) = 0.3, consider adjusting dose if CrCl reduced.
• Sulfamethoxazole is metabolised by CYP2C8/9 and conjugation.

OR

ciprofloxacin HMLSchedNZFPMLnoids Ciprofloxacin F: 0.7 Half life: 4 hours Elimination: renal fe: 0.5 Additional points: Inhibits CYP1A2 and 3A. Antacids, milk, and enteral feeds ↓ absorption.

PO 500 mg twice a day

• fe = 0.5, consider adjusting dose if CrCl reduced.
• Inhibits CYP1A2 (strong) and 3A.
• Subject to OAT and OATP (transporter) inhibition.

Complicated (IV initially then PO based on susceptibilities)

gentamicin HMLSchedNZFPMLnoids Gentamicin F: n/a Half life: 3 hours Elimination: renal fe: 0.9 Additional points: TDM.

IV 5 mg/kg ideal body weight initial dose - see gentamicin guidelines

• fe = 0.9, adjust dose if CrCl reduced.

AND

amoxicillin+clavulanic acid HMLSchedNZFPMLnoids Amoxicillin+Clavulanic Acid F: 0.9 / 0.5 Half life: 2 hours / 1 hour Elimination: renal fe: 0.9 / 0.5

IV 1 g/200 mg every eight hours

• fe (amoxicillin) = 0.9, fe (clavulanic acid) = 0.5, consider adjusting dose if CrCl reduced.

Mild penicillin allergy

• fe = 0.9, adjust dose if CrCl reduced.

AND

cefuroxime HMLSchedNZFPMLnoids Cefuroxime F: 0.4 Half life: 2 hours Elimination: renal fe: 0.9

IV 1.5 g every eight hours

• fe = 0.9, consider adjusting dose if CrCl reduced.

Severe penicillin allergy

Consult Infectious Diseases/Clinical Microbiology

Topic Code: 132587

must be prescribed or recommended by a consultant.