Setting: ED
CC: “It burns when I pee.”
VS: BP: 108/70 mm Hg; P: 104 beats/minute; T: 101.6°F; R: 14 breaths/minute
HPI: A generally healthy 32-year-old woman with fever, urinary frequency, and burning for several days and back pain has arrived at the ED. She had cystitis once several years ago. She has not seen a physician for a long time. She is nauseated and vomited twice.
PMHx/Medications: none
PE:
General: sitting up in bed; uncomfortable
Back: tenderness at the left flank. Costovertebral angle tenderness is present.
Abdomen: nontender; normal bowel sounds
Initial Orders:
Urinalysis (UA)
Blood cultures
CBC
CHEM-7
Escherichia coli is still most common cause of urinary tract infections.
On UA, look for white blood cells (WBCs).
Bacteria on UA is relevant only in pregnancy.
Blood cultures take 2 to 3 days to become positive on CCS.
Report:
UA: WBCs 400/μL; protein trace; nitrite positive
CBC: WBCs 16,700/μL
CHEM-7: normal
Nitrites = Gram-Negative Bacilli
Bacteria convert nitrate to nitrite.
Dysuria + UA WBCs = Urinary Tract Infection (UTI) + Flank Pain = Pyelonephritis
Staphylococcus saprophyticus
• UTI
• Sexually active young women
Dysuria + UA WBC + Suprapubic Pain = Cystitis
Start treatment as soon as blood cultures are obtained and the presence of WBCs is confirmed on UA.
Imaging is not needed prior to starting antibiotics (Figure 10-3).
Figure 10-3. Computed tomography scan of the abdomen showing pyelonephritis in a patient with a urinary tract obstruction from a stone at the ureteropelvic junction. The right kidney is significantly enlarged, with hydronephrosis and perinephric fat stranding. (Reproduced with permission from McKean SC, et al. Principles and Practice of Hospital Medicine. New York: McGraw-Hill; 2012.)
Orders:
Ceftriaxone IV
Renal ultrasound (US)
CCS will expect you to know practical issues, such as, “Do not prescribe pills for vomiting people with pyelonephritis.”
IV Pyelonephritis Therapies
• Ceftriaxone
• Ampicillin and gentamicin
• Aztreonam
• Ciprofloxacin
• Levofloxacin
• Ertapenem
Aztreonam
• Monobactam
• Cell wall inhibitor
• No cross reaction with penicillin
Move the clock forward to get the results of the renal US. The US is not to diagnose pyelonephritis, but to identify a potential correctable etiology.
Renal US to identify:
• Stones
• Strictures
• Tumor
• Obstruction
Report:
Renal US: no stones, no hydronephrosis; enlarged left kidney, edema consistent with pyelonephritis
Advance the clock 6 to 12 hours and do an Interval History. This is the only way to see if the nausea and vomiting has resolved.
The main reason to admit a patient with pyelonephritis is:
Inability to take pills
Hypotension and hemodynamic instability
Nausea and vomiting are common in pyelonephritis.
Interval History: “Nausea is much improved. No further episodes of vomiting today.
Still febrile with temperature 102°F.”
Reports:
Blood cultures: no growth
Urine culture: E. coli, sensitivity pending
CCS will not engage in controversial or unclear practices. Oral and IV pyelonephritis treatment are nearly equal. If you are not certain, keep the patient in the hospital until the sensitivity of the organism is known.
Move the clock forward a day to get the sensitivity of the organism. You can be fully sure the pyelonephritis will resolve by that time.
Reports:
Blood culture: no growth at 3 days
Urine: E. coli sensitive to ciprofloxacin
Orders:
Stop ceftriaxone.
Start oral ciprofloxacin.
Transfer the patient home.
Schedule a follow-up appointment in the office in 7 days.
Quinolones
• They inhibit DNA gyrase.
• Gyrase is needed to unwind genetics so it can reproduce.
• IV and oral blood level are nearly identical.