What is the antibiotic of choice for a patient with a penicillin allergy and suspected urinary tract infection (UTI) with gas in the collecting system after cystoscopy and ureteral stent (double-J stent) placement?

From the Guidelines

For a penicillin-allergic patient with gas in the collecting system after cystoscopy and stent placement, ciprofloxacin would be the antibiotic of choice, given its excellent coverage against common urinary pathogens, including gram-negative bacteria like E. coli and Pseudomonas, as recommended by the European Association of Urology guidelines 1. The presence of gas suggests possible emphysematous pyelonephritis or a gas-forming infection, which requires prompt treatment.

• Key considerations in managing this patient include:
  • The use of ciprofloxacin, which is recommended for patients with a history of anaphylaxis to beta-lactam antimicrobials, as long as the local resistance rate is <10% 1.
  • The importance of managing any urological abnormality and/or underlying complicating factors, such as the stent, which may serve as a nidus for persistent infection 1.
  • The need for adequate hydration and close follow-up, as these are essential components of management. If the patient has severe symptoms or sepsis, intravenous therapy with a non-beta-lactam antibiotic such as gentamicin plus clindamycin would be warranted, as suggested by the Infectious Diseases Society of America guidelines 1.
• It is also important to note that:
  • Most penicillin-allergic patients tolerate cephalosporins, but those with a history of an immediate-type hypersensitivity reaction should be treated with a combination that avoids beta-lactams and carbapenems 1.
  • Ciprofloxacin plus clindamycin or aztreonam plus vancomycin are alternative combinations that can be used in penicillin-allergic patients 1.

From the FDA Drug Label

The bacteriologic cure rates overall for levofloxacin and control at the test-of-cure (TOC) visit for the group of all patients with a documented pathogen at baseline (modified intent to treat or mITT) and the group of patients in the mITT population who closely followed the protocol (Microbiologically Evaluable) are summarized in Table 20

Levofloxacin has in vitro activity against Gram-negative and Gram-positive bacteria fections as described in Indications and Usage (1): Gram-PositiveBacteria Enterococcus faecalis Staphylococcus aureus (methicillin-susceptible isolates) Staphylococcus epidermidis (methicillin-susceptible isolates) Staphylococcus saprophyticus Streptococcus pneumoniae (including multi-drug resistant isolates [MDRSP] ) Streptococcus pyogenes Gram-Negative Bacteria Enterobacter cloacae Escherichia coli Haemophilus influenzae Haemophilus parainfluenzae Klebsiella pneumoniae Legionella pneumophila Moraxella catarrhalis Proteus mirabilis Pseudomonas aeruginosa Serratia marcescens

The antibiotic of choice for a penicillin-allergic patient with gas noted within the collecting system after a cystoscopy and stent placement seven days earlier would be levofloxacin.

• Key points:
  • Levofloxacin has a broad spectrum of activity against both Gram-positive and Gram-negative bacteria.
  • It is effective against common urinary tract pathogens, including Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa.
  • The drug label provides evidence of levofloxacin's efficacy in treating complicated urinary tract infections, including those with bacteriologic cure rates summarized in Table 20 2.
  • Given the patient's penicillin allergy, levofloxacin is a suitable alternative for treating the infection.

From the Research

Antibiotic Choice for Penicillin-Allergic Patient

• The patient has a penicillin allergy and has undergone cystoscopy and stent placement seven days earlier, with gas noted within the collecting system.
• The choice of antibiotic should be guided by the potential causative pathogens and the patient's allergy status.
• According to 3, 90% of patients labeled as 'penicillin-allergic' are able to tolerate penicillin after undergoing a complete evaluation, but in this case, an alternative antibiotic should be chosen.

Potential Causative Pathogens

• The presence of gas within the collecting system suggests a possible infection with a gas-producing organism, such as Pseudomonas aeruginosa.
• 4 and 5 discuss the treatment of Pseudomonas aeruginosa infections, with options including fluoroquinolones, beta-lactams, and beta-lactamase inhibitors.

Antibiotic Options

• Fluoroquinolones, such as ciprofloxacin or levofloxacin, are potential options for treating Pseudomonas aeruginosa infections in penicillin-allergic patients 4, 5.
• However, the use of antibiotics during routine cystoscopic stent removal is being reevaluated, and a study found a low infectious complication rate regardless of antibiotic prophylaxis use 6.
• In this case, the patient has already undergone stent placement and has gas within the collecting system, suggesting a possible infection, so antibiotic treatment may be necessary.

Recommended Antibiotic

• Based on the potential causative pathogens and the patient's penicillin allergy, a fluoroquinolone such as ciprofloxacin or levofloxacin could be considered as an antibiotic option 4, 5.
• However, the final choice of antibiotic should be guided by the patient's specific clinical situation, the results of any available culture and susceptibility data, and consultation with an infectious disease specialist or other expert 7, 3.