A 63 year-old male with a history of hypertension, tobacco use, and nephrolithiasis presents with left-sided flank pain. He notes sudden-onset approximately 4 hours prior to presentation and describes radiation to his groin. Pain was associated with nausea, denies hematuria and states pain is different compared to prior kidney stones. On evaluation, vital signs are notable for tachycardia (114bpm), blood pressure measured at 112/65mmHg. The patient appears uncomfortable and examination is notable for a pulsatile abdominal mass above the umbilicus.
Abdominal Aortic Aneurysm
A point-of-care ultrasound is performed which shows no hydronephrosis and an 8cm infrarenal abdominal aortic aneurysm. Vascular surgery was consulted and a CTA was performed revealing ruptured abdominal aortic aneurysm. Uncrossmatched blood products were administered en route to the operating room due to hypotension.
Algorithm for the Evaluation of Flank Pain with Ultrasound
The POCUS Atlas
The ultrasound images and videos used in this post come from The POCUS Atlas
, a collaborative collection focusing on rare, exotic and perfectly captured ultrasound images.
Abdominal Aortic Aneurysm
Abdominal Aortic Aneurysm
Gallbladder wall thickening
Common bile duct dilation
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- Moore CL, Daniels B, Singh D, Luty S, Molinaro A. Prevalence and clinical importance of alternative causes of symptoms using a renal colic computed tomography protocol in patients with flank or back pain and absence of pyuria. Acad Emerg Med. 2013;20(5):470-478.
- Prince L.A., & Johnson G.A. (2020). Aneurysmal disease. Tintinalli J.E., & Ma O, & Yealy D.M., & Meckler G.D., & Stapczynski J, & Cline D.M., & Thomas S.H.(Eds.),Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 9e. McGraw Hill.
- Bueschen AJ. Flank Pain. In: Walker HK, Hall WD, Hurst JW, editors. Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd edition. Boston: Butterworths; 1990. Chapter 182. Available from: https://www.ncbi.nlm.nih.gov/books/NBK292/
- Carter MR, Green BR. Renal calculi: emergency department diagnosis and treatment. Emerg Med Pract. 2011;13(7):1-17;
This algorithm was developed by Dr. Timothy George. Timothy is an emergency medicine resident at UTHealth Houston.
A 45 year-old female with a history of ureterolithiasis s/p bilateral percutaneous nephrostomies, hypertension and diabetes presents to the emergency department with flank pain and dysuria for two days. She noted that output from her right nephrostomy had diminished. On evaluation, her vital signs are notable for fever and tachycardia but are otherwise normal. Examination demonstrates right costovertebral angle tenderness to percussion. Drain sites appeared normal, without overlying erythema. Urinalyses from both nephrostomy collection bags were submitted. Computed tomography of the abdomen and pelvis was obtained to evaluate for nephrostomy malposition.
CT Abdomen/Pelvis Interpretation
Complex perirenal fluid collection with gas suggestive of emphysematous pyelonephritis with abscess.
The patient was treated with parenteral antibiotics based on prior culture data and was admitted to the intensive care unit with urology consultation and plan for interventional radiology percutaneous drainage. The patient underwent uncomplicated perinephric drain placement and nephrostomy exchange and was discharged on hospital day five to complete a course of oral antibiotics.
An Algorithm for the Evaluation and Management of Emphysematous Urinary Tract Infections
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- Park BS, Lee S-J, Kim YW, Huh JS, Kim JI, Chang S-G. Outcome of nephrectomy and kidney-preserving procedures for the treatment of emphysematous pyelonephritis. Scand J Urol Nephrol. 2006;40(4):332-338. doi:10.1080/00365590600794902.
- Grupper M, Kravtsov A, Potasman I. Emphysematous cystitis: illustrative case report and review of the literature. Medicine (Baltimore). 2007;86(1):47-53. doi:10.1097/MD.0b013e3180307c3a.
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- Yao J, Gutierrez OM, Reiser J. Emphysematous pyelonephritis. Kidney Int. 2007;71(5):462-465. doi:10.1038/sj.ki.5002001.
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- Somani BK, Nabi G, Thorpe P, et al. Is percutaneous drainage the new gold standard in the management of emphysematous pyelonephritis? Evidence from a systematic review. J Urol. 2008;179(5):1844-1849. doi:10.1016/j.juro.2008.01.019.
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- Kapoor R, Muruganandham K, Gulia AK, et al. Predictive factors for mortality and need for nephrectomy in patients with emphysematous pyelonephritis. BJU Int. 2010;105(7):986-989. doi:10.1111/j.1464-410X.2009.08930.x.
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- Lu Y-C, Chiang B-J, Pong Y-H, et al. Predictors of failure of conservative treatment among patients with emphysematous pyelonephritis. BMC Infect Dis. 2014;14(1):418. doi:10.1186/1471-2334-14-418.