Xanthogranulomatous Pyelonephritis Medication

Updated: Mar 15, 2021
  • Author: Samuel G Deem, DO; Chief Editor: Bradley Fields Schwartz, DO, FACS  more...
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Medication Summary

Perioperative antibiotic recommendations are based on the classification of the procedure being performed. Radical nephrectomy for xanthogranulomatous pyelonephritis (XGP) would be considered a clean-contaminated case and would require prophylaxis. The American Urological Association best practice policy recommends either first- or second-generation cephalosporins or an aminoglycoside with metronidazole or clindamycin for 24 hours as first-line prophylaxis. Alternative regimens would include an ampicillin/sulbactam combination or a fluoroquinolone. [26]



Class Summary

Empiric antimicrobial therapy must be comprehensive and should cover all likely pathogens in the context of the clinical setting.

Clindamycin (Cleocin, Cleocin Pediatric)

Clindamycin is a lincosamide semisynthetic antibiotic produced by 7(S)-chloro-substitution of the 7(R)-hydroxyl group of the parent compound lincomycin. This agent inhibits bacterial growth, possibly by blocking the dissociation of peptidyl transfer ribonucleic acid (tRNA) from ribosomes, causing RNA-dependent protein synthesis to arrest. Clindamycin widely distributes in the body, without penetration of the central nervous system (CNS). It is protein bound and excreted by the liver and kidneys.

Clindamycin is available in parenteral (ie, clindamycin phosphate) and oral forms (ie, clindamycin hydrochloride). Oral clindamycin is absorbed rapidly and almost completely and is not appreciably altered by the presence of food in the stomach. Appropriate serum levels are reached and sustained for at least 6 hours following the oral dose. No significant levels are attained in the cerebrospinal fluid (CSF). Clindamycin is also effective against aerobic and anaerobic streptococci (except enterococci).

Metronidazole hydrochloride (Flagyl)

Metronidazole is an imidazole ring-based antibiotic active against various anaerobic bacteria and protozoa. It is used in combination with other antimicrobial agents (except for Clostridium difficile enterocolitis).


Cefazolin is a first-generation semisynthetic cephalosporin, which, by binding to 1 or more penicillin-binding proteins, arrests bacterial cell wall synthesis and inhibits bacterial replication. It has a poor capacity to cross the blood-brain barrier. It is primarily active against skin flora, including Staphylococcus aureus. Regimens for IV and intramuscular (IM) dosing are similar. Cefazolin is typically used alone for skin and skin-structure coverage. It may be administered at 0.5-1.5g IM/IV every 6-8 hours.


Cefotetan is a second-generation cephalosporin with activity against some gram-positive cocci, gram-negative rod infections, and anaerobic bacteria. It inhibits bacterial cell wall synthesis by binding to 1 or more of the penicillin-binding proteins; it inhibits the final transpeptidation step of peptidoglycan synthesis, resulting in cell wall death.

Infections caused by cephalosporin- or penicillin-resistant gram-negative bacteria may respond to cefotetan. Antibiotics have proved effective in decreasing the rate of postoperative wound infection and improving outcome in patients with intraperitoneal infection and septicemia. It may be administered at 1-2g IM/IV every 12 hours.

Ciprofloxacin (Cipro)

Ciprofloxacin is a fluoroquinolone that inhibits bacterial deoxyribonucleic acid (DNA) synthesis and, consequently, growth, by inhibiting DNA gyrase and topoisomerase, which are required for replication, transcription, and translation of genetic material. Quinolones have broad activity against gram-positive and gram-negative aerobic organisms. Ciprofloxacin has no activity against anaerobes. Continue treatment for at least 2 days (7-14 days typical) after signs and symptoms have disappeared. It may be administered at 200-400mg IV every 12 hours.

Ampicillin and sulbactam (Unasyn)

This drug is a combination of beta-lactamase inhibitor with ampicillin that is used as an alternative to amoxicillin when the patient is unable to take oral medication. The combination of ampicillin and sulbactam covers skin flora, enteric flora, and anaerobes, but it is not ideal for nosocomial pathogens. It interferes with bacterial cell wall synthesis during active replication, causing bactericidal activity against susceptible organisms. It may be administered at 1.5-3g IM/IV every 6 hours.


Gentamicin is an aminoglycoside antibiotic for gram-negative coverage. This drug is used in combination with both an agent against gram-positive organisms and one that covers anaerobes.

Note that gentamicin is not the drug of choice. Consider using this drug if penicillins or other less toxic drugs are contraindicated, when clinically indicated, and in mixed infections caused by susceptible staphylococci and gram-negative organisms. The dosing regimens are numerous. Adjust the dose based on creatinine clearance (CrCl) and changes in volume of distribution. Gentamicin may be administered IV/IM.

Aztreonam (Azactam)

Aztreonam is a monobactam, not a beta-lactam, antibiotic that inhibits cell wall synthesis during bacterial growth. This agent has activity against gram-negative bacilli but very limited gram-positive activity, and it is not useful for anaerobes. Aztreonam lacks cross-sensitivity with beta-lactam antibiotics; it may be used in patients allergic to penicillins or cephalosporins.

The duration of aztreonam therapy depends on the severity of the infection and is continued for at least 48 hours after the patient is asymptomatic or evidence of bacterial eradication is obtained. Doses smaller than indicated should not be used.

Transient or persistent renal insufficiency may prolong serum levels. After an initial loading dose of 1 or 2g, reduce the dose by half for an estimated CrCl rate of 10-30 mL/min/1.73 m2. When only serum creatinine concentration is available, the following formula based on sex, weight, and age can approximate CrCl (serum creatinine should represent a steady state of renal function):

In patients with severe renal failure (CrCl < 10 mL/min/1.73 m2) and those supported by hemodialysis, a usual dose of 500mg, 1g, or 2g, is given initially.

The maintenance dose is one fourth of the usual initial dose given at a usual fixed interval of 6, 8, or 12 hours.

For serious or life-threatening infections, supplement the maintenance doses with one eighth of the initial dose after each hemodialysis session.

Elderly persons may have diminished renal function. Renal status is a major determinant of dosage in these patients. Serum creatinine may not be an accurate determinant of renal status. Therefore, as with all antibiotics eliminated by the kidneys, obtain estimates of the CrCl, and make appropriate dosage modifications.

Data are insufficient regarding IM administration to pediatric patients or dosing in pediatric patients with renal impairment. Aztreonam is administered IV only to pediatric patients with normal renal function. It may be administered at 1-2 g IV every 8-12 hours.