urinary calculus (stone, nephrolithiasis, urolithiasis)
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Introduction
Concretions of crystals in the urine, more commonly stones.
Etiology
- composition
- calcium oxalate*
- calcium phosphate*
- uric acid (radiolucent)
- cystine (may be intermediate in radio-opacity)
- ammonium magnesium phosphate (struvite, staghorn calculi, pyelonephritis)
- less common
- xanthine
- oxypurinol
- predisposing factors
- dehydration
- stress
- supersaturation of urine with crystal
- alterations in inhibitors of crystal formation
- pH
- calcium phosphate & struvite stones form in alkaline urine
- uric acid & cystine stones form in acidic urine
- low citrate (RTA type 1)
- pyrophosphates
- low magnesium
- pH
- urine stasis from obstruction
- repeated infection by urease-containing organisms
- high urine pH
- Proteus, Klebsiella, Pseudomonas & others
- struvite stones
- staghorn calculus
- diet high in animal protein (Atkin's diet)
- polycystic kidney disease
- medullary sponge kidney
- renal tubular acidisis (RTA) type 1
- hyperparathyroidism (calcium phosphate)
- gout (uric acid)
- pharmaceutical agents
- carbonic anhydrase inhibitors
- calcium carbonate (milk alkali syndrome)
- allopurinol (xanthine or oxypurinol stones)
- triamterene
- methoxyfluorane (calcium oxalate)
- vitamin D, non thiazide diuretics, steroids (hypercalciuria)
- indinavir
- topiramate[3] calcium phosphate stones
- zonisamide[3]
- chemotherapy (increased uric acid load)
- oral antibiotics increase risk of nephrolithiasis[38]
- intestinal hyperoxaluria (calcium oxalate stones)
- bowel surgery
- Crohn's disease
- ileostomy
- Roux-en-Y gastric bypass surgery[15]
- migraine headaches (RR=1.6)[21]
- genetic predisposition: family history
- pregnancy: 3rd trimester & 1st 3 months postpartum (RR=3)[40]
* calcium stones comprise 75-80% of all stones[3][20]
- most are composed of calcium oxalate
- calcium phosphate (hydroxyapatite) if pregnancy associated[40]
Epidemiology
- 13% of men & 7% of women will develop urinary calculi at some point in their lives[20]
- annual incidence is 0.1%
- men have twice the risk as females
- if untreated 50-75% will have recurrence within 7 years
- 35% to 50% with 5 years[20]
Genetics
- susceptibility to uric acid nephrolithiasis caused by defect in ZNF365 gene
Clinical manifestations
- acute flank pain
- costovertebral angle (CVA) tenderness
- acute colic to dull, persistent pain
- pain may be localized along the urinary tract to the groin
- pain may be abdominal
- nausea/vomiting
- pain not relieved by position
- fever &/or persistent UTI may suggest urinary calculi specially struvite
- hematuria (may be painless)
Laboratory
- urinalysis
- hematuria (biphasic manifestation)[4]
- prevalence highest on the day symptoms begin then declines over several days, then increases
- absence of RBC does not rule out nephrolithiasis
- WBC
- RBC & WBC observed with calculi & UTI
- urine calcium: hypercalciuria
- urine oxalate: hyperoxaluria
- urine citrate: hypocitraturia
- hematuria (biphasic manifestation)[4]
- urine culture:
- urease-containing organisms (Proteus, Klebsiella)
- 24 hour urine*:
- 24 hour urine calcium
- 24 hour urine creatinine
- 24 hour urine uric acid
- increased risk of uric acid stones if > 1000 mg/24 hrs
- phosphorous, citrate, oxalate, cystine
- serum chemistries
- stone profile*
- calculus composition analysis
- inhibitor content
- 75-85% of stones contain calcium
- also see ARUP consult[10]
- also see crystals in urine
* choices of NEJM[44]
Radiology
- abdominal ultrasound
- computed tomography (CT) of abdomen (without contrast)
- gold standard[3] & initial diagnostic test (NEJM)[44]
- ultrasound should be initial diagnostic test[19]
- indicated if ultrasound negative, hematuria associated with pain suggesting urolithiasis[3]
- can identify every type of urinary stone throughout its path through the urinary tract[3]
- may be useful in identifying type of stone (especially calcium stone)[3]
- should not be used to assess children & adolescents with suspected nephrolithiasis[37]
- gold standard[3] & initial diagnostic test (NEJM)[44]
- plain abdominal X-ray (KUB)
- of no use for diagnosis of acute nephrolithiasis[3]
- intravenous pyelogram (IVP)
- urography with nephrotomography
- infared spectroscopy of stone
- X-ray diffraction of stone
Complications
- may be an association between kidney stones & progression to chronic renal failure[3][11]
- reported increase in risk of hypertension, diabetes mellitus, metabolic syndrome[18]
- modest increase in risk of cardiovascular disease in women[18]
- also see specfic urinary stone
Differential diagnosis
- cholecystitis
- appendicitis
- diverticulitis
- UTI concurrent with calculus
- urinary tract tumor
- acute renal failure suggests
- obstructive uropathy
- bilateral obstruction
- obstruction in a solitary kidney
- volume depletion
- sepsis
- obstructive uropathy
Management
- asymptomatic kidney stone found on imaging do not require urgent intervention
- treatment of symptomatic individuals
- pain control:
- NSAIDs may be preferable to opiates[5]
- parenteral ketoralac (Toradol) for acute renal colic
- relief of nausea/vomiting
- rehydration with IV saline if volume depleted
- stone removal or passage
- stones < 5-6 mm in size usually pass spontaneously
- tamsulosin 0.4 mg QD expedites passage of ureteral stones 4-10 mm in size[34]
- nifedipine SA 30 mg or tamsulosin 0.4 mg QD for 5-7 days may reduce ureteral spasms & diminish pain[6]
- tamsulosin superior to nifedipine[7], reduces median time ofstone passage from 5 days to 3 days[14]
- tamsulosin (0.4 mg QD), nifedipine (30 mg QD) for 4 weeks no better than placebo[23][24]
- tamsulosin (0.4 mg QD) reduces time to passage of stones 5-10 mm (7 vs 11 days with placebo)[28];
- no benefit for smaller stones
- alfuzosin reduces median stone passage time 8 days to 5 days & reduces pain
- corticosteroids reduce ureteral edema & facilitate passage of stones
- hydration
- roller coasters may help patients pass kidney stones[35]
- stones > 10 mm require surgery[3]
- ureteroscopy
- stones in the mid-distal ureter
- removal of stone fragments resulting from lithotripsy
- lithotripsy (extracorporeal shock wave therapy)
- stones < 1-1.5 cm in kidney or upper urinary tract (renal pelvis or upper ureter)
- percutaneous nephroscopic removal
- stones >= 1.5 cm
- staghorn calculi
- cystine stones resistant to lithotripsy
- patients with urinary tract abnormalities
- open surgery
- ureteroscopy
- indications for stone removal
- hydronephrosis
- unrelieved pain
- deteriorating renal function
- pyelonephritis
- removal of small asymptomatic kidney stones when removing a larger symptomatic kidney stone prevents subsequent symptomatic renal colic[41]
- stones < 5-6 mm in size usually pass spontaneously
- antibiotic therapy for concurrent UTI
- long-term antibiotics may be needed for large struvite stones
- pain control:
- bladder stones
- transurethral cystolitholapaxy
- open cystostomy if very large stone(s) or very large prostate
- prevention
- adequate hydration > 2.5 L/day* (enough to produce > 2L urine /day)[20]
- diet
- reduced animal protein (uric acid stones)
- increased vegetable fiber
- decreased salt (dietary sodium) intake
- calcium oxalate stones
- reduce dietary oxalate
- reduce animal protein, dietary sodium
- do not restrict calcium intake
- dietary calcium of 800-1200 mg/day
- calcium restriction does not prevent stones, but may actually increase stone formation
- dietary calcium paradoxically decreases risk of calcium oxalate stone formation & recurrence[3]
- calcium restriction contributes to osteoporosis
- increase intake of citrate & potassium
- magnesium is a protective factor in stone formation via binding to oxalate in the intestines & urinary tract, decreasing oxalate absorption & crystallization, respectively[39]
- reduced calorie diet
- avoid colas, which are acidified with phosphoric acid
- does not apply to fruit-flavored soft drinks, which are often acidified with citric acid[20]
- regular riding on a roller coaster may facilitate passage of microscopic & very small calculi passage before symptomatic renal stones can recur[35]
- an equivalent amount of ingested calcium (mass/mass) minimizes urinary oxalate[27]
- calcium carbonate supplements effective
- increase urine pH
- pH > 7 increases uric acid solubility
- pH > 8 increases cystine solubility
- thiazide diuretics* reduce urinary excretion of calcium
- a randomized trial failed to find benefit[43]
- recommended for treatment of nephrolithiasis associated with idiopathic hypercalciuria even the absence of hypertension or edema[3]
- NEJM[44] recommends thiazide diuretics for hypercalciuria & alkaline urine
- thiazide diuretics have been recommended to decrease recurrent nephrolithiasis in people with calcium stones; however, a randomized trial failed to find benefit[43]
- replacement of inhibitor substances
- potassium citrate* 10-30 meq BID[1][8]
- reduces risk of calcium, uric acid, & cystine stones[20]
- NEJM[44] claims potassium citrate may increase risk of calcium phosphate stones in alkaline urine
- pyrophosphate
- magnesium oxide
- potassium citrate* 10-30 meq BID[1][8]
- allopurinol* decreases formation of uric acid
* thiazide diuretic, citrate, or allopurinol recommended if adequate fluid intake is not feasible[20]
* urine alkalinization preferable to allopurinol for uric acid stones unless 24 hour urine uric acid > 1000 mg/day[3]
More general terms
More specific terms
- calcium stone
- cystine stone
- nephrolithiasis; kidney stone
- struvite (magnesium ammonium phosphate) stone
- ureteral stone
- uric acid stone (urate nephropathy, gouty nephropathy)
Additional terms
- 2,8-dihydroxyadenuria
- crystals in urine
- hereditary nephrolithiasis
- hyperoxaluria
- idiopathic hypercalciuria
- xanthinuria
References
- ↑ 1.0 1.1 Saunders Manual of Medical Practice, Rakel (ed), WB Saunders, Philadelphia, 1996, pg 533-34
- ↑ Mayo Internal Medicine Board Review, 1998-99, Prakash UBS (ed) Lippincott-Raven, Philadelphia, 1998, pg 614-16
- ↑ 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12 3.13 3.14 Medical Knowledge Self Assessment Program (MKSAP) 11, 14, 15, 16, 17, 18, 19. American College of Physicians, Philadelphia 1998, 2006, 2009, 2012, 2015, 2018, 2021
- ↑ 4.0 4.1 Journal Watch 23(23):184-85, 2003 Kobayashi T et al, J Urol, 170:1093, 2003 PMID: https://www.ncbi.nlm.nih.gov/pubmed/14501699
- ↑ 5.0 5.1 Journal Watch 24(16):125, 2004 Holdgate A, Pollock T. Systematic review of the relative efficacy of non-steroidal anti-inflammatory drugs and opioids in the treatment of acute renal colic. BMJ. 2004 Jun 12;328(7453):1401. Epub 2004 Jun 03. Review. <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/15178585 <Internet> http://bmj.bmjjournals.com/cgi/content/full/328/7453/1401
- ↑ 6.0 6.1 Prescriber's Letter 11(9): 2004 Use of Nifedipine or Tamsulosin for Kidney Stones Detail-Document#: http://prescribersletter.com/(5bhgn1a4ni4cyp2tvybwfh55)/pl/ArticleDD.aspx?li=1&st=1&cs=&s=PRL&pt=3&fpt=25&dd=200911&pb=PRL (subscription needed) http://www.prescribersletter.com
- ↑ 7.0 7.1 Journal Watch 25(17):135, 2005 Dellabella M, Milanese G, Muzzonigro G. Randomized trial of the efficacy of tamsulosin, nifedipine and phloroglucinol in medical expulsive therapy for distal ureteral calculi. J Urol. 2005 Jul;174(1):167-72. PMID: https://www.ncbi.nlm.nih.gov/pubmed/15947613
- ↑ 8.0 8.1 Robinson MR et al. Impact of long-term potassium citrate therapy on urinary profiles and recurrent stone formation. J Urol 2009 Mar; 181:1145. PMID: https://www.ncbi.nlm.nih.gov/pubmed/19152932
- ↑ 9.0 9.1 Moesbergen TC et al. Distal ureteral calculi: US follow-up. Radiology 2011 Aug; 260:575. PMID: https://www.ncbi.nlm.nih.gov/pubmed/21555351
- ↑ 10.0 10.1 ARUP Consult: Nephrolithiasis - Kidney Stone The Physician's Guide to Laboratory Test Selection & Interpretation https://www.arupconsult.com/content/nephrolithiasis
Nephrolithiasis Testing Algorithm https://arupconsult.com/algorithm/nephrolithiasis-testing-algorithm - ↑ 11.0 11.1 Alexander RT et al. Kidney stones and kidney function loss: A cohort study. BMJ 2012 Aug 30; 345:e5287 PMID: https://www.ncbi.nlm.nih.gov/pubmed/22936784
- ↑ Worcester EM, Coe FL Clinical practice. Calcium kidney stones. N Engl J Med. 2010 Sep 2;363(10):954-63. PMID: https://www.ncbi.nlm.nih.gov/pubmed/20818905
- ↑ Goldfarb DS. In the clinic. Nephrolithiasis. Ann Intern Med. 2009 Aug 4;151(3):ITC2. PMID: https://www.ncbi.nlm.nih.gov/pubmed/19652185
- ↑ 14.0 14.1 Parsons JK, Hergan LA, Sakamoto K, Lakin C. Efficacy of alpha-blockers for the treatment of ureteral stones. J Urol. 2007 Mar;177(3):983-7; PMID: https://www.ncbi.nlm.nih.gov/pubmed/17296392
- ↑ 15.0 15.1 Kumar R, Lieske JC, Collazo-Clavell ML et al Fat malabsorption and increased intestinal oxalate absorption are common after Roux-en-Y gastric bypass surgery. Surgery. 2011 May;149(5):654-61. PMID: https://www.ncbi.nlm.nih.gov/pubmed/21295813
- ↑ Eisner BH, Eisenberg ML, Stoller ML. Relationship between body mass index and quantitative 24-hour urine chemistries in patients with nephrolithiasis. Urology. 2010 Jun;75(6):1289-93 PMID: https://www.ncbi.nlm.nih.gov/pubmed/20018350
- ↑ Taylor EN, Fung TT, Curhan GC. DASH-style diet associates with reduced risk for kidney stones. J Am Soc Nephrol. 2009 Oct;20(10):2253-9 PMID: https://www.ncbi.nlm.nih.gov/pubmed/19679672
- ↑ 18.0 18.1 18.2 Ferraro PM et al History of Kidney Stones and the Risk of Coronary Heart Disease. JAMA. 2013;310(4):408-415 <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/23917291 <Internet> http://jama.jamanetwork.com/article.aspx?articleid=1719741
- ↑ 19.0 19.1 19.2 Smith-Bindman R et al. Ultrasonography versus computed tomography for suspected nephrolithiasis. N Engl J Med 2014 Sep 18; 371:1100. <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/25229916 <Internet> http://www.nejm.org/doi/full/10.1056/NEJMoa1404446
- ↑ 20.0 20.1 20.2 20.3 20.4 20.5 20.6 20.7 Qaseem A et al Dietary and Pharmacologic Management to Prevent Recurrent Nephrolithiasis in Adults: A Clinical Practice Guideline From the American College of Physicians. Ann Intern Med. 2014;161(9):659-667 <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/25364887 <Internet> http://annals.org/article.aspx?articleid=1920506
- ↑ 21.0 21.1 Tsai MJ, Chen YT, Ou SM, Shin CJ, Peng KP, Tang CH, Wang SJ. Increased risk of urinary calculi in patients with migraine: A nationwide cohort study. Cephalalgia. 2014 Oct 15. PMID: https://www.ncbi.nlm.nih.gov/pubmed/25319966
- ↑ WebMD: Potassium Citrate for Kidney Stones http://www.webmd.com/kidney-stones/potassium-citrate-for-kidney-stones
- ↑ 23.0 23.1 Pickard R, Starr K, MacLennan G et al. Medical expulsive therapy in adults with ureteric colic: A multicentre, randomised, placebo-controlled trial. Lancet 2015 May 18; <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/25998582 <Internet> http://www.thelancet.com/journals/lancet/article/PIIS0140-6736%2815%2960933-3/abstract
- ↑ 24.0 24.1 Prescriber's Letter 22(8): 2015 (subscription needed) Medical Expulsive Therapy for Kidney Stones: Does it Help? Detail-Document#: http://prescribersletter.com/(5bhgn1a4ni4cyp2tvybwfh55)/pl/ArticleDD.aspx?li=1&st=1&cs=&s=PRL&pt=3&fpt=25&dd=310805&pb=PRL http://www.prescribersletter.com
- ↑ Cleveland Clinic Kidney Stones: Oxalate-Controlled Diet http://my.clevelandclinic.org/services/urology-kidney/treatments-procedures/kidney-stones-oxalate-controlled-diet
- ↑ Chai W, Liebman M Oxalate content of legumes, nuts, and grain-based flours. Journal of Food Composition and Analysis 18 (2005) 723-729 http://www.2ndchance.info/oxalate-dogChai2005oxalatecontentfoods.pdf
- ↑ 27.0 27.1 Liebman M1, Chai W. Effect of dietary calcium on urinary oxalate excretion after oxalate loads. Am J Clin Nutr. 1997 May;65(5):1453-9. PMID: https://www.ncbi.nlm.nih.gov/pubmed/9129476
- ↑ 28.0 28.1 Furyk JS et al. Distal ureteric stones and tamsulosin: A double-blind, placebo-controlled, randomized, multicenter trial. Ann Emerg Med 2016 Jan; 67:86 <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/26194935 <Internet> http://www.annemergmed.com/article/S0196-0644%2815%2900480-1/abstract
- ↑ Fulgham PF, Assimos DG, Pearle MS, Preminger GM. Clinical effectiveness protocols for imaging in the management of ureteral calculous disease: AUA technology assessment. J Urol. 2013 Apr;189(4):1203-13. Review. PMID: https://www.ncbi.nlm.nih.gov/pubmed/23085059
- ↑ Goldfarb DS, Arowojolu O. Metabolic evaluation of first-time and recurrent stone formers. Urol Clin North Am. 2013 Feb;40(1):13-20. Review. PMID: https://www.ncbi.nlm.nih.gov/pubmed/23177631 Free PMC Article
- ↑ Pearle MS. Shock-wave lithotripsy for renal calculi. N Engl J Med. 2012 Jul 5;367(1):50-7 PMID: https://www.ncbi.nlm.nih.gov/pubmed/22762318
- ↑ Sakhaee K, Maalouf NM, Sinnott B. Clinical review. Kidney stones 2012: pathogenesis, diagnosis, and management. J Clin Endocrinol Metab. 2012 Jun;97(6):1847-60. Review. PMID: https://www.ncbi.nlm.nih.gov/pubmed/22466339 Free PMC Article
- ↑ Frassetto L, Kohlstadt I. Treatment and prevention of kidney stones: an update. Am Fam Physician. 2011 Dec 1;84(11):1234-42. Review. PMID: https://www.ncbi.nlm.nih.gov/pubmed/22150656 Free Article
- ↑ 34.0 34.1 34.2 Wang RC, Smith-Bindman R, Whitaker E et al. Effect of tamsulosin on stone passage for ureteral stones: A systematic review and meta-analysis. Ann Emerg Med 2016 Sep 8; PMID: https://www.ncbi.nlm.nih.gov/pubmed/27616037
- ↑ 35.0 35.1 35.2 Mitchell MA, Wartinger DD Validation of a Functional Pyelocalyceal Renal Model for the Evaluation of Renal Calculi Passage While Riding a Roller Coaster. The Journal of the American Osteopathic Association. October 2016, Vol. 116, 647-652. <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/27669068 <Internet> http://jaoa.org/article.aspx?articleid=2557373
- ↑ 36.0 36.1 Heilberg IP, Goldfarb DS. Optimum nutrition for kidney stone disease. Adv Chronic Kidney Dis. 2013 Mar;20(2):165-74. Review. PMID: https://www.ncbi.nlm.nih.gov/pubmed/23439376
- ↑ 37.0 37.1 American Urological Association Fifteen Things Physicians and Patients Should Question Released February 21, 2013 (1-5), June 11, 2015 (6-10), May 13, 2017 (11-15); sources for #5 revised May 9, 2016 http://www.choosingwisely.org/societies/american-urological-association/
- ↑ 38.0 38.1 Tasian GE, Jemielita T, Goldfarb DS et al Oral Antibiotic Exposure and Kidney Stone Disease. JASN May 10, 2018 <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/29748329 <Internet> http://jasn.asnjournals.org/content/early/2018/05/09/ASN.2017111213
- ↑ 39.0 39.1 Tavasoli S, Taheri M, Taheri F, Basiri A, Bagheri Amiri F. Evaluating the associations between urinary excretion of magnesium and that of other components in calcium stone-forming patients. Int Urol Nephrol. 2019 Feb;51(2):279-284 PMID: https://www.ncbi.nlm.nih.gov/pubmed/30515733
- ↑ 40.0 40.1 40.2 Thongprayoon C, Vaughan LE, Chewcharat A et al. Risk of symptomatic kidney stones during and after pregnancy. Am J Kidney Dis 2021 Sep; 78:409. PMID: https://www.ncbi.nlm.nih.gov/pubmed/33867205 PMCID: PMC8384636 (available on 2022-09-01) https://www.ajkd.org/article/S0272-6386(21)00402-9/fulltext
- ↑ 41.0 41.1 Sorensen MD et al. Removal of small, asymptomatic kidney stones and incidence of relapse. N Engl J Med 2022 Aug 11; 387:506 PMID: https://www.ncbi.nlm.nih.gov/pubmed/35947709 https://www.nejm.org/doi/10.1056/NEJMoa2204253
- ↑ 42.0 42.1 Ganesan C et al. National imaging trends for suspected urinary stone disease in the emergency department. JAMA Intern Med 2022 Oct 31; [e-pub]. PMID: https://www.ncbi.nlm.nih.gov/pubmed/36315134 PMCID: PMC9623481 (available on 2023-10-31) https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2798196
Smith-Bindman R et al. Unchanged diagnostic imaging for urinary stone disease - Where do we go from here? JAMA Intern Med 2022 Oct 31; [e-pub]. PMID: https://www.ncbi.nlm.nih.gov/pubmed/36315160 https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2798198 - ↑ 43.0 43.1 43.2 Dhayat NA, Bonny O, Roth B et al. Hydrochlorothiazide and prevention of kidney-stone recurrence. N Engl J Med 2023 Mar 2; 388:781-791 PMID: https://www.ncbi.nlm.nih.gov/pubmed/36856614 https://www.nejm.org/doi/10.1056/NEJMoa2209275
Alexander RT. Do thiazides reduce the risk of kidney-stone recurrence? N Engl J Med 2023 Mar 2; 388:841-842 PMID: https://www.ncbi.nlm.nih.gov/pubmed/36856621 https://www.nejm.org/doi/10.1056/NEJMe2300120 - ↑ 44.0 44.1 44.2 44.3 44.4 NEJM Knowledge+ Nephrology/Urology
- ↑ D'Alessandro C, Ferraro PM, Cianchi C, et al. Which diet for calcium stone patients: A real-world approach to preventive care. Nutrients. 2019;11. PMID: https://www.ncbi.nlm.nih.gov/pubmed/31137803
- ↑ National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Kidney Stones https://www.niddk.nih.gov/health-information/urologic-diseases/kidney-stones