Is colistin given in pyelonephritis?

From the Guidelines

Colistin is not recommended as a first-line treatment for pyelonephritis, and its use should be reserved for severe infections caused by multidrug-resistant gram-negative bacteria. The European Association of Urology guidelines on urological infections recommend fluoroquinolones and cephalosporins as the only antimicrobial agents for oral empiric treatment of uncomplicated pyelonephritis 1. Colistin is considered a last-resort antibiotic due to its potential for nephrotoxicity and neurotoxicity.

If colistin is used in pyelonephritis, it would only be in cases where the causative organism is resistant to all other antibiotics and susceptible to colistin, based on culture and sensitivity testing. The decision to use colistin should be made by a specialist, typically an infectious disease physician, after careful consideration of the risks and benefits. The dosing would need to be adjusted based on renal function, as both the infection itself and the medication can impact kidney function.

Some key points to consider when using colistin include:

• Monitoring renal function during colistin treatment 1
• Using a loading dose of 9 MU (5 mg/kg) of colistin followed by a maintenance dose of 4.5 MU (2.5 mg (1.5 CrCl + 30)) twice daily in critically-ill patients 1
• Weighing the benefits and risks of colistin-based combination therapy, as its use is controversial 1
• Being aware of the potential for acute kidney injury during and after colistin treatment, which is one of the most important factors related to clinical failure and mortality 1.

Overall, the use of colistin in pyelonephritis should be approached with caution and only considered in specific cases where the benefits outweigh the risks.

From the Research

Use of Colistin in Pyelonephritis

• Colistin is used as a last-line treatment against infections caused by multidrug-resistant gram-negative bacteria, including those that cause pyelonephritis 2.
• A study published in 2019 examined the use of colistin for the treatment of urinary tract infections, including pyelonephritis, caused by extremely drug-resistant Pseudomonas aeruginosa 3.
• The study found that colistin was effective in treating pyelonephritis, with a clinical cure rate of 89.5% in patients who received colistin monotherapy 3.
• However, the study also noted that the use of colistin was associated with a significant risk of nephrotoxicity, with 29.4% of patients developing acute kidney injury 3.
• Another study published in 2009 reported a 93% rate of favorable clinical outcome in patients treated with colistin for various infections, including urinary tract infections 4.
• The study also noted that renal toxicity was encountered in 12 patients, but was severe in only two cases 4.
• Colistin is considered a treatment option for urinary tract infections caused by multidrug-resistant Gram-negative bacteria, including those that cause pyelonephritis 5, 6.
• The use of colistin for pyelonephritis is typically reserved for cases where other treatment options are limited due to resistance or other factors 6.

Key Considerations

• The dosage of colistin used to treat pyelonephritis is critical, and should be carefully adjusted based on the patient's renal function and other factors 3.
• Combination therapy with other antibiotics may be considered in some cases, particularly when the infecting pathogen has a high minimum inhibitory concentration (MIC) for colistin 2.
• Therapeutic drug monitoring is recommended to ensure that the patient is receiving an effective dose of colistin while minimizing the risk of toxicity 2.