In an 84‑year‑old male with a suprapubic catheter who is on amoxicillin‑clavulanate (875 mg/125 mg) twice daily for a presumed urinary tract infection, now presenting with leg cellulitis, groin itching, leukocytosis, and a creatinine rise to 1.7 mg/dL while receiving oral prednisone, should the Augmentin be continued (with renal dose adjustment) for cellulitis and have repeat CBC and CMP performed next week?

Recommendation for Cellulitis Management in This Patient

Continue Augmentin for the cellulitis with renal dose adjustment to 875/125 mg once daily (given creatinine 1.7), monitor closely for clinical response over the next 3-5 days, and obtain repeat CBC/CMP within one week—but address the groin itching as a potential fungal superinfection requiring antifungal therapy. 1, 2

Rationale for Continuing Augmentin

The IDSA guidelines clearly support amoxicillin-clavulanate as an appropriate first-line oral agent for typical cellulitis, as it provides excellent coverage against streptococci (the primary pathogen) and staphylococci 1. Since you cannot confirm whether the leg cellulitis has worsened or improved on Augmentin, and the patient remains afebrile with stable vitals, there is no evidence of treatment failure that would mandate a change in antibiotic therapy.

Key Clinical Considerations:

• No purulent drainage documented: The guidelines emphasize that β-lactam monotherapy (like Augmentin) is appropriate for non-purulent cellulitis without features suggesting MRSA 1
• Leukocytosis (WBC 15.9) in context of prednisone: The elevated WBC is likely multifactorial—both infection and corticosteroid effect—making it less reliable as a sole marker of treatment failure
• Stable vital signs and afebrile status: These are reassuring signs that severe systemic infection is not present

Critical Issue: Renal Dose Adjustment Required

With creatinine 1.7 (up from 1.4), you must reduce the Augmentin dose immediately. 2 The standard 875/125 mg BID dosing is inappropriate for this level of renal impairment. Adjust to:

• 875/125 mg once daily for CrCl 10-30 mL/min (estimate based on age and creatinine)
• This prevents drug accumulation and further nephrotoxicity while maintaining adequate tissue levels for cellulitis treatment

The Groin Itching: A Red Flag

The groin itching with documented redness is highly suggestive of candidal intertrigo or fungal superinfection, a common complication in patients on:

• Broad-spectrum antibiotics (Augmentin)
• Corticosteroids (prednisone)
• With indwelling catheters and likely moisture/maceration in the groin area

Action needed: Add topical antifungal therapy (e.g., clotrimazole or nystatin cream BID) to the groin area. This is NOT a reason to stop the Augmentin for cellulitis.

The Urinary Findings: Do Not Overinterpret

The UA showing moderate leukocyte esterase and bacteria but no microscopic WBCs and negative nitrites in a patient with a suprapubic catheter represents catheter-associated asymptomatic bacteriuria (CA-ABU), not active UTI requiring treatment change 3. Key points:

• Patients with indwelling catheters universally develop bacteriuria
• Without fever, systemic symptoms, or pyuria on microscopy, this does not require antibiotic escalation 3
• The Augmentin prescribed for "presumed UTI" is now appropriately covering the cellulitis

Monitoring Plan: Specific Parameters

Within 3-5 days (not waiting a full week):

• Reassess the leg cellulitis for objective improvement: decreased erythema, warmth, swelling
• If cellulitis is not improving by day 5, consider:
  • Blood cultures (given leukocytosis and immunosuppression from prednisone) 1
  • Imaging to rule out deeper infection or abscess
  • Possible need for MRSA coverage if risk factors emerge

Within 7 days:

• Repeat CBC to assess WBC trend (should decrease if infection improving)
• Repeat CMP to monitor creatinine (critical given dose adjustment and baseline renal impairment)
• Doppler results to exclude DVT as alternative/concurrent diagnosis

Duration of Therapy

The IDSA guidelines support 5 days of antibiotic therapy for uncomplicated cellulitis if clinical improvement has occurred 1. However, given:

• Advanced age (84 years)
• Immunosuppression (prednisone)
• Renal impairment
• Inability to confirm baseline status

Plan for 7-10 days total therapy, reassessing at day 5 for clinical improvement before deciding final duration.

Common Pitfalls to Avoid

1. Do not stop Augmentin based solely on the groin itching—treat the fungal superinfection separately
2. Do not ignore the rising creatinine—dose adjustment is mandatory to prevent toxicity
3. Do not treat the catheter-associated bacteriuria in the absence of systemic UTI symptoms 3
4. Do not wait a full week to reassess—cellulitis should show improvement by 3-5 days or warrants investigation for complications
5. Do not add MRSA coverage empirically without purulent drainage, penetrating trauma, or evidence of treatment failure 1

The Prednisone Factor

The concurrent prednisone is a double-edged sword: it may actually help reduce cellulitis inflammation 1, but it also increases infection risk and masks fever. The IDSA notes that systemic corticosteroids (prednisone 40 mg daily for 7 days) can be considered in nondiabetic adults with cellulitis 1. Continue the prednisone as prescribed, but maintain heightened vigilance for infection progression.