From the FDA Drug Label
When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy. 2.3 Dosage in Adult Patients with Renal Impairment In adult patients with renal impairment (creatinine clearance ≤ 40 mL/min) and dialysis patients (hemodialysis and CAPD), the intravenous dose of piperacillin and tazobactam for injection should be reduced based on the degree of renal impairment
For community-acquired pneumonia with Acute Kidney Injury (AKI), the dosage of piperacillin-tazobactam should be adjusted based on the degree of renal impairment.
- The recommended daily dosage is described in Table 1.
- For patients with creatinine clearance 20-40 mL/min, the recommended dose is 2.25 grams every 6 hours.
- For patients with creatinine clearance less than 20 mL/min, the recommended dose is 2.25 grams every 8 hours.
- For patients on hemodialysis, the maximum dose is 2.25 grams every 12 hours and an additional dose of 0.75 grams should be administered after each dialysis session. 1
From the Research
For community-acquired pneumonia (CAP) in a patient with acute kidney injury (AKI), I recommend using a combination of ceftriaxone and azithromycin as the initial antibiotic regimen, with careful monitoring and dose adjustments as needed to minimize additional kidney injury. This recommendation is based on the most recent and highest quality study available, which suggests that this combination is associated with lower odds of developing AKI compared to other regimens 2.
Key Considerations
- Ceftriaxone 1-2g IV once daily does not require renal adjustment, making it a suitable choice for patients with AKI.
- Azithromycin 500mg IV/PO daily can be used in combination with ceftriaxone, and its dose does not need to be adjusted in patients with AKI.
- Levofloxacin 750mg IV/PO can be used as an alternative, but its dose should be reduced based on creatinine clearance to minimize the risk of nephrotoxicity.
- For severe CAP, consider adding vancomycin or linezolid if MRSA is suspected, with careful monitoring and dose adjustment based on levels and renal function.
Rationale
The study by 3 found that the combination of piperacillin/tazobactam and vancomycin was associated with the highest odds of developing AKI, highlighting the importance of choosing an antibiotic regimen that minimizes the risk of nephrotoxicity. The study by 2 provides guidance on the diagnosis and treatment of CAP, including the use of β-lactam/macrolide combination therapy for hospitalized patients without risk factors for resistant bacteria.
Monitoring and Adjustments
Regular monitoring of renal function is essential during treatment, with dose adjustments as kidney function changes. This includes monitoring serum creatinine levels, urine output, and other markers of kidney function. By choosing an appropriate antibiotic regimen and carefully monitoring and adjusting doses as needed, clinicians can minimize the risk of additional kidney injury and improve outcomes for patients with CAP and AKI.