One of my friends from residency sent me this video. It’s perfect.
My line favorite is:
There is multiple medical mysteries but I’m a renal super sleuth
and my one diagnostic tool is the golden window of truth.
Check!
The highest urine specific gravity I have ever seen
1.050 is really high. Even the healthiest kidneys can’t concentrate urine past a specific gravity of 1.030. To get this high the urine must contain another substance.
In this patient’s case she had just undergone a heart catheterization. IV contrast is rapidly cleared by the kidney and increased the density of the sample. Proteinuria and glucosuria are other conditions which can cause an abnormally high urine specific gravity.
Sterile Pyuria [updated]
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?