From the Guidelines
For treating pyelonephritis associated with staghorn calculi, the best empiric antibiotic regimen typically includes broad-spectrum coverage with an intravenous combination of a third-generation cephalosporin (such as ceftriaxone 1-2g IV every 24 hours) plus an aminoglycoside (such as gentamicin 5-7mg/kg IV once daily), as recommended by the European Association of Urology guidelines 1. The choice of empiric antibiotics should be based on local resistance patterns and optimized.
- The regimen should be initiated promptly before urine culture results are available.
- Once culture and sensitivity results return, therapy should be narrowed to target the specific organisms.
- Treatment duration typically ranges from 10-14 days, with transition to oral antibiotics when clinically improved.
- Staghorn calculi often harbor multiple organisms including Proteus, Klebsiella, Pseudomonas, and Enterococcus species, which produce urease enzymes that create alkaline urine and promote stone formation.
- Importantly, antibiotic therapy alone is insufficient; definitive management requires surgical removal of the calculus (usually through percutaneous nephrolithotomy) to eliminate the nidus of infection and prevent recurrent infections and kidney damage, as suggested by the European Association of Urology guidelines 1. Alternative options for empiric treatment include a carbapenem like meropenem (1g IV every 8 hours) or a combination of piperacillin-tazobactam (4.5g IV every 6-8 hours), as listed in the suggested regimens for empirical parenteral antimicrobial therapy for uncomplicated pyelonephritis 1.
- The European Society of Clinical Microbiology and Infectious Diseases (ESCMID) guidelines also provide recommendations for the treatment of infections caused by multidrug-resistant gram-negative bacilli, including the use of carbapenems and novel broad-spectrum antimicrobial agents 1. It is essential to note that the treatment of pyelonephritis associated with staghorn calculi requires a comprehensive approach, including prompt antibiotic therapy, surgical removal of the calculus, and management of any underlying conditions that may be contributing to the development of the infection.
From the Research
Empiric Antibiotics for Staghorn Calculus Pyelonephritis
The choice of empiric antibiotics for treating staghorn calculus pyelonephritis depends on various factors, including the causative organism and local antibiotic resistance patterns.
- The most common organisms causing staghorn calculus pyelonephritis are urease-producing bacteria, such as Proteus mirabilis, Klebsiella pneumoniae, and Pseudomonas aeruginosa 2.
- Preoperative urine cultures are essential for guiding antibiotic therapy, and a computed tomography scan can help identify any complications 2.
- The goal of antibiotic therapy is to eradicate the infection and prevent recurrence, and long-term or short-term antibiotic therapy may be recommended 2.
- Regular control imaging exams and urine culture should be done to monitor the patient's response to treatment 2.
Surgical Approach
The gold standard surgical technique for treating staghorn renal stones is percutaneous nephrolithotomy (PCNL) 2.
- PCNL can be performed in supine or prone position, according to the surgeon's experience 2.
- Tranexamic acid can be used to avoid bleeding during the procedure 2.
- Shockwave lithotripsy and flexible ureteroscopy are useful tools to treat residual fragments that can be left after treatment of complete staghorn renal stone 2.
Conservative Management
Conservative management of staghorn calculi may be considered in patients who are unable or unwilling to undergo surgical treatment 3.
- A retrospective analysis of 29 patients with staghorn calculi treated conservatively found that kidney function remained stable in 66% of patients, and none of the patients required hemodialysis 3.
- However, there is a need for future prospective studies to determine the safety and efficacy of conservative treatment for staghorn calculi 3.