Management of Persistent Fever with Right CVA Tenderness
This patient requires immediate evaluation for acute pyelonephritis or other urological infection, not continued treatment for upper respiratory infection. The combination of persistent fever despite antibiotics, right costovertebral angle tenderness, and flank pain on leg raise strongly suggests a urinary tract source rather than respiratory pathology.
Critical Clinical Reassessment Required
The physical examination findings have fundamentally changed the clinical picture:
- Right CVA tenderness is a red flag for pyelonephritis or perinephric abscess and demands urgent investigation regardless of the absence of urinary symptoms 1, 2
- Pain on leg raise confined to the right flank further localizes pathology to the kidney or retroperitoneal space
- Persistent fever after 3-5 days of antibiotic therapy requires systematic reassessment including review of all culture results, meticulous physical examination, and diagnostic imaging of suspected infection sites 3
Immediate Diagnostic Workup
Order the following tests urgently:
- Urinalysis with microscopy and urine culture - essential even without dysuria, as pyelonephritis can present with minimal urinary symptoms
- Complete blood count with differential - to assess for leukocytosis and left shift indicating bacterial infection
- Basic metabolic panel - to evaluate renal function and electrolyte abnormalities
- Blood cultures - given persistent fever despite antibiotics 3
- Renal ultrasound or CT abdomen/pelvis with contrast - to evaluate for pyelonephritis, perinephric abscess, or nephrolithiasis with obstruction 3
The lumbar X-ray suggested by the previous teleconsultation is not the appropriate next imaging study given the acute presentation with fever and CVA tenderness.
Antibiotic Management Modification
Azithromycin is inadequate coverage for urinary tract pathogens:
- Azithromycin has limited activity against common uropathogens like E. coli, Klebsiella, and Proteus species 4, 5
- The drug was appropriately chosen for presumed respiratory infection but does not cover typical pyelonephritis organisms
- If pyelonephritis is confirmed, switch to fluoroquinolone (ciprofloxacin or levofloxacin) or third-generation cephalosporin pending culture results 3
Fever Management Considerations
While awaiting diagnostic results:
- Continue paracetamol for symptomatic fever control as needed, though it has limited efficacy in reducing fever and should not mask clinical deterioration 6, 7
- Monitor temperature trends closely - persistent high fever (>39°C) despite antipyretics suggests serious bacterial infection requiring hospitalization 1
Upper Respiratory Symptoms - Secondary Consideration
The initial respiratory symptoms (dry cough, nasal discharge) have reportedly improved:
- Most viral URIs resolve within 1-2 weeks without antibiotics 2
- The slight left nostril swelling without erythema is consistent with resolving viral rhinitis 8
- The respiratory component is likely viral and self-limited - the azithromycin was unnecessary for this indication 2
Clinical Pitfalls to Avoid
- Do not attribute persistent fever to the initial respiratory complaint when new physical findings suggest alternative pathology 3
- Do not continue the same antibiotic regimen when fever persists beyond 3-5 days without reassessment 3
- Do not dismiss CVA tenderness in the absence of dysuria - pyelonephritis can present atypically
- Do not order lumbar spine imaging before ruling out acute infectious processes that require urgent treatment
Disposition Decision
If imaging confirms pyelonephritis or abscess, hospitalization for IV antibiotics is indicated. If outpatient management is pursued after negative imaging, close follow-up within 24-48 hours is mandatory with clear return precautions for worsening symptoms 3, 1.