check the pee lab rounds aug 7 th, 2008 kristian hecht
TRANSCRIPT
![Page 1: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/1.jpg)
Check the pee
Lab rounds Aug 7th, 2008
Kristian Hecht
![Page 2: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/2.jpg)
Case 1
• 22y female 3 day hx of dysuria, frequency and urgency. Afebrile.
• Urine dip: +leuks, +nitrite, +RBC’s• Urinalysis:
RBC 20 0-5/hpf
WBC 30 0-5/hpf
Epithelial Few 0/hpf
Bacteria Many 0/hpf
Casts None 0/hpf
![Page 3: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/3.jpg)
Case 1
• 22y female 3 day hx of dysuria, frequency and urgency. Afebrile.
• Urine dip: +leuks, +nitrite, +RBC’s• Urinalysis: RBC 20 0-5/hpf
WBC 30 0-5/hpf
Epithelial Few 0/hpf
Bacteria Many 0/hpf
Casts None 0/hpf
![Page 4: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/4.jpg)
Dipsticks in UTI
• Multisticks measure Sp. gravity, pH, glucose, nitrites, protein, leuks, rbc’s, bili, ketones
• Leuks and nitrites are the most useful in suspected UTI
![Page 5: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/5.jpg)
Dipsticks
• WBC’s measured indirectly measuring leukocyte esterase activity
• LE contained in neutrophils and macrophages
• Sp 80-90%
• Sn 75-96%
• False –ve’s: high glc, high prot, tetracycline, keflex
![Page 6: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/6.jpg)
Dipsticks
• Nitrites produced by most Gm –ve uropathogens
• Not produced by Pseudomonas or Enterococcus
• Diet must contain nitrates to be +ve
• Sn <50%
• Sp >90%
![Page 7: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/7.jpg)
Dipsticks
• In children <12y, when compared to microscopy, urine dips were equally as accurate Pediatrics 104:54, 1999
• Less accurate in children <2y
• In adults with a typical UTI hx, some advocate for empiric tx with no further investigation based on a +ve dip
![Page 8: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/8.jpg)
Microscopy
• Urine spun at 2000rpm for 5 min
• Sediment is resuspended in remaining urine and examined + gram staining
• WBC’s– >5/hpf in females, >2/hpf in males
• Bacteria– >15/hpf
![Page 9: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/9.jpg)
Case 2
• 18y f, 3d hx of dysuria, frequency and urgency• Dipstick +ve leuks, -ve for nitrite
• Micro: RBC 1 0-5/hpf
WBC 30 0-5/hpf
Epithelial 0 0/hpf
Bacteria 0 0/hpf
Casts None 0/hpf
![Page 10: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/10.jpg)
Microscopy
• WBC’s– False negatives: dilute urine, leukopenia,
partial treatment
• Bacteria– Negative if: C. trachomatis, N. gonorrhea,
HSV, S. saprophyticus– False –ve if: dilute urine, low bacterial load
![Page 11: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/11.jpg)
Case 2 con’t
• Further hx indicates recent unprotected intercourse with a new partner 10d ago
• Swabs taken
• Teachable moment seized
![Page 12: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/12.jpg)
Urine Culture
• Provides definitive diagnosis
• >105 CFU/mL considered positive
• correlated with 95% likelyhood of infection
• >104 CFU/mL correlated with only 50% likelyhood
![Page 13: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/13.jpg)
Urine Culture
• False +ve cultures are common due to contamination from uropathogens on the perineum and foreskin
• Many studies show that urine culture is only useful when the diagnosis is uncertain or when there are host factors that make pathogen identification important
![Page 14: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/14.jpg)
Groups in Which Urine Culture is Indicated
1. Children 2. Adult men 3. Immunocompromised patients 4. "Treatment failure" (recently completed course of antibiotics with persistent urinary symptoms) 5. Patients with symptoms in excess of 4 to 6 days 6. Elderly patients at risk for bacteremia 7. Toxic-appearing patients with signs and symptoms suggestive of pyelonephritis or bacteremia 8. Pregnant women 9. Patients with known chronic or recurrent renal infection 10. Patients with known anatomic urologic abnormalities 11. Patients in whom urinary tract obstruction is suspected (e.g., stones, benign prostatic hypertrophy) 12. Patients with serious medical diseases, including diabetes mellitus, sickle cell anemia, cancer, or other debilitating diseases 13. Patients with alcoholism, drug dependence 14. Recently hospitalized patients 15. Patients taking antibiotics 16. Patients recently instrumented (e.g., cystoscopy, catheterization)
![Page 15: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/15.jpg)
Case 3
• 75y male unresponsive, tachycardic, hypotensive, afebrile
• Had complained of flank pain 24h ago
• Hx of BPH and mild UTI’s in past
![Page 16: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/16.jpg)
Case 3
• While working this pt up for presumed urosepsis a urine was sent off…
• Micro pH 6.0
RBC 10 0-5/hpf
WBC 2 0-5/hpf
Epithelial Mod - Necrotic renal tubular cells
0/hpf
Bacteria Few 0/hpf
Casts Many – epithelial casts
0/hpf
Crystals Many - Oxalate mono/dihydrate
0/hpf
![Page 17: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/17.jpg)
Case 3
• A neighbor comes by the ICU the next day and mentions that the pt had seemed depressed lately.
• Pt also asked to borrow some antifreeze for his car 3 days ago…
![Page 18: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/18.jpg)
![Page 19: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/19.jpg)
Crystals
• Crystals may be normally found in urine based on diet, concentration and pH– Urate, oxalate
• Pathologic crystals– Cholesterol – indicates marked proteinuria– Cystine – familial cystinuria– Drugs (Acyclovir, Amoxil, Cipro, Indinavir)
• Can be implicated in cases of ATN
![Page 20: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/20.jpg)
![Page 21: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/21.jpg)
Casts
• Form when urinary ‘Tamm-Horsfall’ proteins precipitate with low pH or incr. concentration
• Cellular debris can become entrapped in this precipitate
• May help differentiate causes of acute renal failure and renal disease
![Page 22: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/22.jpg)
RBC cast
![Page 23: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/23.jpg)
Granular cast Waxy cast
![Page 24: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/24.jpg)
Casts
• Acute tubular necrosis– necrotic renal tubular epithelial cells (RTEC)– RTEC casts
• Proliferative/Necrotic GN/vasculitis – erythrocytic casts
• Rhabdomyolysis – myogolbin casts• Calcium oxalate crystals – ethylene glycol
![Page 25: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/25.jpg)
Casts
• Nephrotic syndrome– Proteinuria, lipuria with RTEC and fatty casts
• Degree of hematuria can indicate underlying cause (mininmal change, membranous, focal segmental…)
• Nephritic syndrome– Mod/Severe dysmorphic hematuria
• RTEC casts and/or waxy casts
![Page 26: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/26.jpg)
Other Casts
• Hyaline – prerenal azotemia, normal
• Granular – renal disease of any cause
• Leukocytic – Pyelonephritis/acute interstitial nephritis
![Page 27: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/27.jpg)
Take home goodies
• Think about STI’s when the microscopy doesn’t fit with the story/dip
• Don’t culture everyone
• Crystals and casts can be useful in differentiating causes of ARF
![Page 28: Check the pee Lab rounds Aug 7 th, 2008 Kristian Hecht](https://reader035.vdocuments.site/reader035/viewer/2022062518/56649e895503460f94b8df64/html5/thumbnails/28.jpg)
Thanks!