Patient came in yesterday with a three month history of frequent UTIs. These UTIs were diagnosed when the patient presented to her doctor with back/flank pain and the U/A was positive for leukocyte esterase and white cells but was always nitrate negative and the cultures never revealed more than low colony counts of skin flora.
The patient’s pain repeatedly responded to a few days of quinolone therapy.
Differential for sterile pyuria:
- Renal TB: patient’s husband had a history of active TB
- Interstitial nephritis: patient was taking a significant amount of NSAIDs and ASA for the back pain
- Nephrolithiasis: patient had calcifications in the kidney on the U/S
- Urogenital cancer
- Vaginal contamination
- Glomerulonephritis
- Chlamydia, mycoplasma, ureaplasma (thanks Jim)
Others?
Chlamydia? It can definitely cause sterile pyuria, and a few days of a quinolone might suppress it but would not eradicate it, prompting the recurrence of symptoms.
Mycoplasma and Ureaplasma spp. can also give sterile pyuria. Analgesic nephropathy, too.
The TB history is concerning, though, especially with calcifications in the kidney…since renal TB can lead to parenchymal scarring & calcification.
Good list! Thanks!
Jim, thanks for your comment.
Almost as soon as I posted I kicked myself for not including chlamydia.
In terms of analgesic nephropathy do you consider this a unique clinical entity from interstitial nephritis?
Joel