Kidney Symptoms: Flank and Back Pain
Flank pain describes back discomfort located on one or both sides of the spine between the lower edge of the rib cage and the upper border of the pelvis. When flank pain occurs on both sides, it often resembles a backache. Flank pain develops in association with a variety of kidney conditions and diseases because this is the location of the kidneys. As kidney-related causes of flank pain are potentially serious, contact your doctor without delay if you experience discomfort in this area of your back.
A kidney infection, also known as pyelonephritis, is a leading cause of flank pain. With this condition, bacteria that initially infects the bladder travels upstream to infect the kidney(s). Urinary tract infections, including kidney infections, are more common in women than men. Pregnancy increases the risk for pyelonephritis should bacteria gain entry into the urinary tract. Aching flank pain associated with a kidney infection usually begins suddenly, persists and is accompanied by fever, chills, abdominal pain, and nausea and vomiting as well as urinary urgency, frequency and painful urination.
- A kidney infection, also known as pyelonephritis, is a leading cause of flank pain.
The Location & Symptoms of Kidney Pain
A stone is another common cause of kidney-related flank pain. Kidney stones form when chemicals normally dissolved in the urine form solid crystals that coalesce and grow in size. Flank pain associated with a kidney stone develops when urine flow from the kidney to the bladder is blocked. The pain typically begins suddenly, comes in waves and becomes increasingly severe over time to the point of excruciating intensity. In fact, a kidney stone is one of the most painful conditions a person can experience. The sharp flank pain often radiates into the abdomen and/or the scrotum or labia. Accompanying signs and symptoms include pink or bloody urine, nausea and vomiting. In some people, flank pain due to a kidney stone is more mild and intermittent, particularly if the obstruction of urine flow develops gradually. Men are more likely to develop a kidney stone than women.
- A stone is another common cause of kidney-related flank pain.
- In some people, flank pain due to a kidney stone is more mild and intermittent, particularly if the obstruction of urine flow develops gradually.
Other Kidney Disorders
A number of other kidney disorders can trigger flank pain, although they are less common than pyelonephritis and kidney stones. Other possible kidney-related causes of flank pain include:
- Traumatic kidney injury
- Kidney tumor or cyst(s)
- Narrowing, malformation or malfunction of the ureter (the tube that carries urine from the kidney to the bladder)
- Blood clot in the ureter
- Kidney abscess
- Papillary necrosis (death of kidney tissue where urine flows into the ureter)
What Are the Causes of Left Flank Pain?
Not all pain in the flank area of the back is caused by an underlying kidney disorder. Muscle strains and nerve- or spine-related back problems are commonly to blame. Lack of other symptoms is a key feature of musculoskeletal flank pain. Conditions arising from other organs can also refer pain to the flank area of the back, including:
- Pulmonary embolism (a blood clot in the lung)
- Ectopic pregnancy (pregnancy outside the uterus)
- Gallbladder inflammation or obstruction
- Bowel obstruction
- Peptic ulcer disease
- Abdominal aortic aneurysm (ballooning of the aorta, the largest artery of the body)
- Not all pain in the flank area of the back is caused by an underlying kidney disorder.
- Lack of other symptoms is a key feature of musculoskeletal flank pain.
Warnings and Precautions
Because many conditions and diseases can cause flank pain, it's important to see your doctor as soon as possible to determine the underlying cause and appropriate treatment. Seek urgent medical care if you develop flank pain and are pregnant. Urgent medical care is also needed if your pain is severe or you experience any warning signs or symptoms that might indicate a serious underlying cause, including:
- Sudden difficulty breathing or shortness of breath
- Chest pain
- High fever
- Shaking chills or cold, clammy skin
- Dizziness, lightheadedness or fainting
- Severe or worsening abdominal pain
Reviewed and revised by: Tina M. St. John, M.D.
The Location & Symptoms of Kidney Pain
What Are the Causes of Left Flank Pain?
Causes of Lower Left-Side Abdominal Pain
Is Low Potassium Associated With UTIs?
Causes of Low Back Pain and Kidney Infection
Infections Caused by Untreated Kidney Stones
Causes of Pain in the Lower Right Quadrant
Causes of Hemoglobinuria
What Are the Causes of Pain in the Left Lower Back?
Causes of Left Side Abdominal Pain in Females
- Merck Manual Professional Version: Bacterial Urinary Tract Infections (UTIs)
- Patient.info Professional Reference: Acute Pyelonephritis
- Cleveland Clinic Center for Continuing Education: Nephrolithiasis
- Comprehensive Clinical Nephrology, 4th Edition; Jurgen Floege, Richard Johnson and John Feehally
- EB Medicine: Renal Calculi: Emergency Department Diagnosis And Treatment
- Family Practice Notebook: Abdominal Pain Evaluation
- Dewar MJ, Chin JL. Chronic renal pain: An approach to investigation and management. Can Urol Assoc J. 2018;12(6 Suppl 3):S167-S170. doi:10.5489/cuaj.5327
- Akcay A, Turkmen K, Lee D, Edelstein CL. Update on the diagnosis and management of acute kidney injury. Int J Nephrol Renovasc Dis. 2010;3:129-40. doi:10.2147/IJNRD.S8641
- Belyayeva M, Jeong JM. Acute Pyelonephritis. StatPearls Publishing. Updated February 28, 2019.
- Venkatesh L, Hanumegowda RK. Acute Pyelonephritis - Correlation of Clinical Parameter with Radiological Imaging Abnormalities. J Clin Diagn Res. 2017;11(6):TC15-TC18. doi:10.7860/JCDR/2017/27247.10033
- Erlich T, Kitrey ND. Renal trauma: the current best practice. Ther Adv Urol. 2018;10(10):295-303. doi:10.1177/1756287218785828
- European Association of Urology. EAU Guidelines: Urological Trauma.
- Mujoomdar M, Russell E, Dionne F, et al. Suspected Obstructive Uropathy. Optimizing Health System Use of Medical Isotopes and Other Imaging Modalities [Internet]. Ottawa (ON): Canadian Agency for Drugs and Technologies in Health; 2012.
- Algaba F. Renal adenomas: pathological differential diagnosis with malignant tumors. Adv Urol. 2008;:974848. doi:10.1155/2008/974848
- Muglia VF, Prando A. Renal cell carcinoma: histological classification and correlation with imaging findings. Radiol Bras. 2015;48(3):166-74. doi:10.1590/0100-3984.2013.1927
- Harris PC, Torres VE. Polycystic Kidney Disease, Autosomal Dominant. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle. Updated July 19, 2018.
- Bukhari S, Amodu A, Akinyemi M, Wallach S. Persistent hematuria caused by renal cell carcinoma after aortic valve replacement and warfarin therapy. Proc (Bayl Univ Med Cent). 2017;30(3):327-329.
- Halvorson CR, Bremmer MS, Jacobs SC. Polycystic kidney disease: inheritance, pathophysiology, prognosis, and treatment. Int J Nephrol Renovasc Dis. 2010;3:69-83.
- Finnigan NA, Leslie SW. Polycystic Kidney Disease, Adult. StatPearls Publishing. Updated February 3, 2019.
- Chapman AB, Devuyst O, Eckardt KU, et al. Autosomal-dominant polycystic kidney disease (ADPKD): executive summary from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference. Kidney Int. 2015;88(1):17-27. doi:10.1038/ki.2015.59
- Smith DA, Nehring SM. Bacteremia. StatPearls Publishing. Updated November 15, 2018.
- Westphalen AC, Hsia RY, Maselli JH, Wang R, Gonzales R. Radiological imaging of patients with suspected urinary tract stones: national trends, diagnoses, and predictors. Acad Emerg Med. 2011;18(7):699-707. doi:10.1111/j.1553-2712.2011.01103.x
- Gounden V, Jialal I. Renal Function Tests. StatPearls Publishing. Updated April 3, 2019.
- Gowda S, Desai PB, Kulkarni SS, Hull VV, Math AA, Vernekar SN. Markers of renal function tests. N Am J Med Sci. 2010;2(4):170-3.
- Louie RJ, Tonneson JE, Gowarty M, Goodney PP, Barth RJ, Rosenkranz KM. Complete blood counts, liver function tests, and chest x-rays as routine screening in early-stage breast cancer: value added or just cost? Breast Cancer Res Treat. 2015;154(1):99-103. doi:10.1007/s10549-015-3593-y
- Engelsgjerd JS, Deibert CM. Cystoscopy. StatPearls Publishing. Updated March 15, 2019.
- Elshazzly M, Bashjawish F, Shahid MA, Marrero DA, Horowitz J. A Challenging Case of Retroperitoneal Abscess in a Post-Partum Crohn's Disease Patient. Am J Case Rep. 2018;19:773-777. doi:10.12659/AJCR.909545
- Chi AC, Flury SC. Urology patients in the nephrology practice. Adv Chronic Kidney Dis. 2013;20(5):441-8. doi:10.1053/j.ackd.2013.05.002
- Mclellan LK, Hunstad DA. Urinary Tract Infection: Pathogenesis and Outlook. Trends Mol Med. 2016;22(11):946-957. doi:10.1016/j.molmed.2016.09.003
- Harbell J, Terrault NA, Stock P. Solid organ transplants in HIV-infected patients. Curr HIV/AIDS Rep. 2013;10(3):217-25. doi:10.1007/s11904-013-0170-z
- Sohail M, Khurshid M, Saleem HG, Javed H, Khan AA. Characteristics and Antibiotic Resistance of Urinary Tract Pathogens Isolated From Punjab, Pakistan. Jundishapur J Microbiol. 2015;8(7):e19272. doi:10.5812/jjm.19272v2
- Codjoe FS, Donkor ES. Carbapenem Resistance: A Review. Med Sci (Basel). 2017;6(1). doi:10.3390/medsci6010001
- Shoobridge JJ, Corcoran NM, Martin KA, Koukounaras J, Royce PL, Bultitude MF. Contemporary management of renal trauma. Rev Urol. 2011;13(2):65-72.
- Jo KI, Yang NR, Jeon P, Kim KH, Hong SC, Kim JS. Treatment Outcomes with Selective Coil Embolization for Large or Giant Aneurysms : Prognostic Implications of Incomplete Occlusion. J Korean Neurosurg Soc. 2018;61(1):19-27. doi:10.3340/jkns.2016.0101.018
- Dagli M, Ramchandani P. Percutaneous nephrostomy: technical aspects and indications. Semin Intervent Radiol. 2011;28(4):424-37. doi:10.1055/s-0031-1296085
- Li W, Cheng Y, Cheng Y, Ren H, Han N. Clinical efficacy of radical nephrectomy versus nephron-sparing surgery on localized renal cell carcinoma. Eur J Med Res. 2014;19:58. doi:10.1186/s40001-014-0058-4
- Guler S, Cimen S, Hurton S, Molinari M. Diagnosis and Treatment Modalities of Symptomatic Polycystic Kidney Disease. In: Li X, editor. Polycystic Kidney Disease [Internet]. Brisbane (AU): Codon Publications; 2015.
- Bonsib, S. Renal Cystic Diseases and Renal Neoplasms: A Mini-Review. Clin J Amer Soc Nephrol. 2009:4(12):1998-2007. DOI: 10.2215/CJN.02020309.
- Castner, D. A closer look at pyelonephritis. Nursing 2013. 2013;43(10):63. DOI: 10.1097/01.NURSE.0000434322.10150.26.
- Mourmourisa, P.; Chiras, T; and Papatsoris, A. Obstructive Uropathy: From Etiopathology to Therapy. World J Nephrol Urol. 2014;3(1):1-6. DOI: 10.14740/wjnu154w.
- Shoobridge, J.; Corcoran, N.; Martin, K. et al. Contemporary Management of Renal Trauma. Rev Urol. 2011;13(2):65-72.
Shelly Morgan has been writing and editing for over 25 years for various medical and scientific publications. Although she began her professional career in pharmacological research, Morgan turned to patent law where she specialized in prosecuting patents for medical devices. She also writes about renal disease and hypertension for several nonprofits aimed at educating and supporting kidney patients.