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Three Part Question

[ in a patient presenting with loin pain] [ is ultrasound better than IVP] [ in detecting urinary calculi] ?

Clinical Scenario

A 35 year old male comes to A&E complaining of severe pain in his loin. After initial KUB and urinalysis, the registrar on duty questions which method; US or IVP, is better at detecting calculi.

Search Strategy

Ovid/medline R 1966- June week 4 2005
Embase 1980- 2005 week 27
Pubmed
[exp Kidney Diseases/ or exp Hematuria/ or exp Syndrome/ or exp Kidney/] OR [loin pain.mp. [mp=title, original title, abstract, name of substance word, subject heading word] 0R
[exp Urinary Calculi/ or exp Kidney Diseases/ or exp Kidney Calculi/] OR [renal colic.mp. [mp=title, original title, abstract, name of substance word, subject heading word] AND
[exp Ultrasonography/ or exp ULTRASOUND, HIGH-INTENSITY FOCUSED, TRANSRECTAL/ or exp Ultrasonography, Interventional/] OR [ultrasound.mp. [mp=title, original title, abstract, name of substance word, subject heading word] AND [exp Kidney/ or exp Contrast Media/ or exp Urography/] OR [exp Kidney Diseases/ or exp Contrast Media/ or exp Urography/ or exp Urologic Diseases/] OR [exp Urography/ or exp Ultrasonography, Interventional/] OR [IVU.mp. [mp=title, original title, abstract, name of substance word, subject heading word] AND [KIDNEY STONES.mp. or exp Kidney Calculi/] OR [RENAL CALCULI.mp. or exp Kidney Calculi/] OR
[CALCULI.mp. or exp URETERAL CALCULI/ or CALCULI/ or exp URINARY CALCULI/]
limit 21 to humans

Search Outcome

896 PAPERS FOUND ovid
1241 PAPERS FOUND embase
6 PAPERS FOUND PUBMED
19 PAPERS RELEVENT however after discarding foriegn language material, 17 REMAINED. Of these 5 are of good quality to use plus 3 abstracts of full text papers yet to arrive.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
F.C. Laing, R.B. Jeffrey, V.W. Wing. 1985 USA	Patients presenting to the ED with acute flank pain during a 24 month period.	Clinical Trial: to compare ultrasound and urography in evaluating acute loin pain. An US was performed prior to urography in 20 patients . The results were evaluated by 2 different radiologists who were unaware of the results of the other examiner.	number of ureteral calculi shown on US and IVU	US showed calculi in 2 patients. IVU showed ureteral calcui in 14 patients	Incomplete bladder filling meant that there was an inability to visualise the distal ureter on US therefore allowing possible calculi to be overlooked.
L. Dalla Palma, F. Stacul, M. Bazzocchi, L. Pagnan, G. Festini, D. Marega 1993 Italy	Patients with suspected ureteric colic presenting to the ED over a 8 month period from Jan 1991 to Aug 1991	Clinical Trial: 105 patients with renal colic had a KUB+US and an IVU within 3.5 days. These were performed by 15 different radiologists who were on duty throughout the 24 hours. The patients were then followed up by telephone within a month.	The ability of each modality to detect calculi and their senstivity and specificity.	IVU was positive in 44 of the 105 patients. US was positive in 42 of these 44. IVU was negative in 61 patients. US was negative in 41 of these. Sensitivity of US 95% specificity 67%. 60 patients did not undergo IVU - 29 had a positive diagnosis with US.	Some patients were lost to follow up. Also IVU was performed 3.5 days after the US in which time a stone may have been passed. The results were reviewed by 15 different radiologists of varying expertese and training in image interpretation therefore affecting the accuracy of the study.
S.O Henderson, R.J Hoffner, J.L Aragona, D.E Groth, V.I Esekogwu, D. Chan 1998	patients presenting with unilateral flank pain over an 8month period between July 1996 and Feb 1997	clinical trial: 108 consecutive patients attending the ED were given a KUB, US and IVU. The procedures were video recorded and reviewed by radiology staff without any knowledge of the results obtained in the emergency department.	sensitivity and specificity of US and IVU at detecting calculi..	IVU detected 69 cases of calculi. US detected 67- sensitivity 97.1% (95% CI:93.1-100%) Of 39 normal kidneys depicted by IVU, 29 were confirmed normal with US+KUB. KUB+US combination falsely positive in 16 patients- specificity 58.9% (95% CI:43.5-74.3%) overall accuracy 83.3%	variable amount of US training among the physicians. also on average 4-5 patients per month were not enrolled or did not complete the study due to their refusal to wait the amount of time necessary to complete.
S. Yilmaz, T. Sindel, G. Arslan, C. Ozkaynak, K. Karaali, A. Kabaalioglu, E. Luleci 1998 Turkey	Patients presenting with renal colic during a 17 month period from June 1995 to Dec 1996	Clinical Trial: to compare US and IVU in their detection of ureteric calculi. 97 patients were examined on the same day with US and IVU. The results were blindly interpreted by 2 radiologist. The final decisions were made by consensus.	sensitivity and specificity of US and IVU and their accuracy at detecting calculi	US detected 12 out of 64 patients with ureteral calculi -sensitivity 19% specificity 97% accuracy 45% PPV 92% NPV 38%. IVU detected calculi in 33 out of 64 patients- sensitivity 52% specificity 94% accuracy 66% PPV 94% NPV 50%. US found 5 renal stones, IVU found 7 renal stones.	True positive and negative cases were based on the observation of the patients as to whether they passed a stone or not. Small stones could have been missed by the patients and so the number of false negative cases will have been underestimated and the false positive cases overestimated.
N. Juul, J. Brons, S. Torp-Pedersen, K.E Fredfeldt 1991 Scandinavia	Patients admitted to the radiology department for emergency IVU.	Clinical Trial: to compare US and IVU and their ability to detect renal and ureteral stones. 102 consecutive patients undertook US immediately before emergency IVU. The scans were performed by specialists who were unaware of the results of the other modality.	The ability of US and IVU to detect renal obstruction and ureteral stones	IVU depicted obstruction in 53 of the 102 patients. US found obstruction in 50 cases. US and IVU both found 18 kidney stones. IVU found 40 of the 46 ureteral stones. US found only 18 out of 46 ureteral stones.	full text not yet available
J. Spencer, D. Lindsell, I. Mastorakou 1990	Patients refered to the ED from GP and hospital outpatient clinics with haematuria.	Clinical Trial: to compare US and IVU in detecting masses. Both techniques were performed on 155 consecutive patients. The investigations were performed independently on routine lists by different duty radiologists.	number of masses detected by US and IVU	81 patients had normal findings on US and IVU. The findings concurred in 144 cases (93%). US missed 2 ureteric calculi however detected 4 bladder tumours not seen on IVU. US clarified the nature of 3 masses found on IVU	full text not yet available
D. Sinclair, S. Wilson, A. Toi, L. Greenspan 1989	Patients presenting to the Emergency Department with acute flank pain	Clinical Trial: prospective study of 98 patients to determine the accuracy of US compared to IVU for diagnosing urinary tract calculi. Both imaging examinations were perfomed independently and reviewed by 2 radiologists who were blinded to the results of the other test and the clinical outcome.	number of calculi found by US and IVU and their sensitivities and specificity.	US found calculi in 44 out of the 69 patients- sensitivity 64% specificity 100% P>0.05 by Chi Squared test. IVU found calculi in 44 patients. In the presence of hydonephrosis US found 59 out of 69 patients with calculi- sensitivity 85% specificity 100%. IVU identified 62 out of the 69 patients- sensitivity 90% specificity 94%. Both modality detected calculi missed by the other modality.	Complete follow up could not be performed on seven patients. 4 patients passed a calculus after or during ultrasound scanning. Also the quality of the IVU films was variable- 29 were inadequate or incomplete. The quality of the USS were also variable with 14 being deemed inadequate.
M.C Hill,J.I Rich, J.G Mardiat, C.A Finder 1985	61 patients with flank pain	Clinical Trial: prospective study to compare the accuracy of sonography and IVU in determining the cause of acute flank pain.	accuracy of US and IVU in detecting stones	IVU made correct diagnosis in 85% of patients. US made correct diagnosis in 66% of patients. small stones at the UV junction detected by US 79% and IVU 68%.	FULL TEXT NOT YET AVAILABLE

Comment(s)

US in a busy clinical scenario in the ED is a sufficiently sensitive method to use as an initial investigation and as an effective screening tool for patients presenting with loin pain. US is easily used and cheaper than IVU as well as less time consuming.

Clinical Bottom Line

IVU remains the better imaging technique, however US with KUB may replace IVU as a sensitive technique to view the urinary tract for pathology in the ED.

References

1. F.C. Laing, R.B. Jeffrey, V.W. Wing. Ultrasound versus excretory urography in evaluating acute flank pain Radiology 1985; 54; 613-616
2. L. Dalla Palma, F. Stacul, M. Bazzocchi, L. Pagnan, G. Festini, D. Marega Ultrasonography and plain film versus intravenous urography in ureteric colic Clinical Radiology 1993;47:333-336
3. S.O Henderson, R.J Hoffner, J.L Aragona, D.E Groth, V.I Esekogwu, D. Chan bedside emergency department ultrasonography plus radiography of the kidneys, ureter and bladder vs intravenous pyelography in the evaluation of suspected ureteral colic Academic Emergeny Medicine 1998; 5:666-671
4. S. Yilmaz, T. Sindel, G. Arslan, C. Ozkaynak, K. Karaali, A. Kabaalioglu, E. Luleci Renal colic:comparison of spiral CT, US and IVU in the detection of ureteral calculi. European Radiology 1998;8:212-217
5. N. Juul, J. Brons, S. Torp-Pedersen, K.E Fredfeldt Ultrasound versus intravenous urography in the intitial evaluation of patients with suspected obstructing urinary calculi. Scandinavian Journal of Urology& Nephrology Supplementum 1991; 137:45-47
6. J. Spencer, D. Lindsell, I. Mastorakou Ultrasonography compared with intravenous urography in the investigation of adults with haematuria BMJ 1990 Nov 10;301(6760):1074-6
7. D. Sinclair, S. Wilson, A. Toi, L. Greenspan The evaluation of suspected renal colic: ultrasound versus excretory urography Annals of Emergency Medicine 1989; 18(5): 556-9
8. M.C Hill,J.I Rich, J.G Mardiat, C.A Finder Sonography vs. excretory urography in acute flank pain American Journal of Roentgenology Jun 1985; 144(6):1235-8