Urinary tract obstruction can be induced by a myriad of conditions and is defined as a renal disease that causes hydronephrosis and leads to significant changes in normal kidney function [1] [2] [3] [4]. Narrowing or complete obstruction of the ureteropelvic or ureterovesical junctions, ureterocele, phimosis, and the presence of posterior urethral valves are common causes of congenital urinary tract obstruction, whereas nephrolithiasis, urinary tract infections (UTIs), benign prostatic hyperplasia (BPH), malignant tumors (both primary and metastatic), diabetic neuropathy, trauma, and use of several drugs (anticholinergics and alpha-adrenergic antagonists) are important acquired etiologies [1] [2] [4] [5] [6]. Depending on the degree of obstruction (unilateral vs. bilateral) and the rate at which hydronephrosis develops, symptoms are either abrupt or slowly progressive. In the acute setting, a sudden onset of sharp and often severe abdominal pain (known as renal colic) is the hallmark of urinary tract obstruction and is often accompanied by diminished urine output (ranging from oliguria to anuria) in complete obstruction [5] [6]. Pain might project into the genitalia if the lower urinary tract is the site of obstruction [6]. In slowly progressive forms, pain may be mild or even absent, while dysuria, nocturia, increased frequency and urgency, as well as a sensation of incomplete bladder emptying, are often reported [2] [6].

• Hypoxemia

  Venovenous extracorporeal membrane oxygenation was initiated on the first day of life for severe respiratory failure and consecutive hypoxemia despite treatment with inhaled nitric oxide and high-frequency oscillation. [ncbi.nlm.nih.gov]

• Abdominal Pain

  PATIENT CONCERNS: A 58-year-old man complained of right lower abdominal pain with hematuria for 3 hours after flexible ureteroscopy, combined with holmium laser lithotripsy of right renal calculi was performed 1 month ago. [ncbi.nlm.nih.gov]

  Signs and symptoms include: Inability to pass urine (urinary retention) Weak stream of urine Interrupted stream Blood in the urine Pain in either flank (side) or in the back Abdominal pain and/or swelling Prostate enlargement (in men), which may be benign [gmcdhcc.com]

  Symptoms of a stricture include pain with urination, slow urination, decreased bladder emptying, spraying of the urinary stream, blood in the urine, abdominal pain from a full bladder, urethral discharge, and bladder infections. [urology.ucsf.edu]

  pain that may be triggered or worsened during states of increased diuresis (e.g., after caffeine or alcohol consumption). [amboss.com]

  Most patients present with nonspecific symptoms, including dull abdominal pain, of less than 12 months' duration but patients can present with the complications of the fibrosis. [patient.info]

• Hypertension

  Evidence exists of an association with metabolic syndrome, obesity, diabetes and hypertension, and of enhanced risk of chronic kidney disease and metabolic bone disease. [ncbi.nlm.nih.gov]

  The remaining twelve sections cover various types of diseases, including hypertension, urological problems, and urinary tract concerns. [books.google.de]

  Intrarenal varices in portal hypertension: demonstration by color Doppler imaging. Abdom Imaging 1996;21:549–50. CrossRef PubMed Google Scholar 9. Kember PG, Peck RJ. Renal arteriovenous malformation mimicking hydronephrosis. [link.springer.com]

  For instance, it has been shown that protein released by the kidneys in diabetes mellitus sensitises the kidney to the damaging effects of hypertension. [1] Diabetes also can have a direct effect on urination due to peripheral neuropathies, which occur [en.wikipedia.org]

• Perseveration

  Nonetheless, our drive to assess and manage fetal obstructive uropathy perseveres so that we may ultimately relieve obstruction and preserve renal and lung function. [ncbi.nlm.nih.gov]

• Neglect

  Various hypotheses have been advanced in the literature to account for this neglected syndrome. A trial was carried out to assess whether all patients presenting with uterine prolapse should be screened to exclude urinary tract obstruction. [ncbi.nlm.nih.gov]

• Meningism

  At the same time the patient had chronic meningitis from Histoplasma capsulatum. The literature on renal involvement with histoplasmosis is reviewed. [ncbi.nlm.nih.gov]

• Urinary Retention

  A 41-year-old man presented in urinary retention 36 hours after self-injecting his urethra with the foam sealant, which could be palpated throughout his entire urethra. [ncbi.nlm.nih.gov]

  It is a cause of urinary retention. [en.wikipedia.org]

  Medication, alcohol, postoperative urinary retention, diabetes mellitus. [urology-textbook.com]

• Dysuria

  Endometriosis: recurrent flank pain, dysuria, hematuria Extra-uterine pregnancy Tuboovarial abscess Pelvic floor insufficiency with organ prolapse Tumors: cervical cancer, ovarian cysts, ovarian cancer, uterine leiomyoma ... [urology-textbook.com]

  When infection is present, the patient may experience fever, chills, and dysuria. Hematuria may also be present. [emedicine.medscape.com]

  In slowly progressive forms, pain may be mild or even absent, while dysuria, nocturia, increased frequency and urgency, as well as a sensation of incomplete bladder emptying, are often reported. [symptoma.com]

  […] the bladder falls into the vagina) Foreign objects Urethral or pelvic muscle spasms Inguinal (groin) hernia The symptoms of BOO may vary, but can include: Abdominal pain Continuous feeling of a full bladder Frequent urination Pain during urination ( dysuria [medlineplus.gov]

• Uremia

  We report on a 52-year-old female patient hospitalized because of uremia due to bilateral urinary tract obstruction caused by bilateral sarcomatoid renal cell carcinoma (SRCC). [ncbi.nlm.nih.gov]

   Nausea, vomiting, loss of weight and strength, and pallor are due to uremia secondary to bilateral hydronephrosis. 10.  SIGNS  Lower and midtract  Palpation of the urethra  induration about a stricture.  Rectal examination  atony of the anal [slideshare.net]

  Urine constituents are reabsorbed by the renal veins, tubes, and lymphatic channels, leading to uremia. Because complete urinary tract obstruction can lead to renal failure, treatment must be prompt. [britannica.com]

  When bilateral obstruction or unilateral obstruction in a solitary kidney is severe and renal failure has occurred, uremia can be present. Uremia symptoms include weakness, peripheral edema, mental status changes, and pallor. [emedicine.medscape.com]

• Urinary Hesitancy

  Chronic lower tract obstruction Usual signs and symptoms include: Urinary hesitancy. Narrow and weak urine stream. Dribbling at end of micturition. Feeling of incompletely emptied bladder. [patient.info]

  hesitancy) Slow, uneven urine flow, at times being unable to urinate Straining to urinate Urinary tract infection Waking up at night to urinate ( nocturia ) Your health care provider will ask about your symptoms and medical history. [medlineplus.gov]

• Oliguria

  Patients range from having oliguria / anuria to only having asymptomatic hydronephrosis that is incidentally identified through imaging or elevated creatinine levels. [amboss.com]

  In the acute setting, a sudden onset of sharp and often severe abdominal pain (known as renal colic) is the hallmark of urinary tract obstruction and is often accompanied by diminished urine output (ranging from oliguria to anuria) in complete obstruction [symptoma.com]

  Suspect obstructive uropathy when patients have unexplained renal insufficiency, decreased urine output, pain that suggests obstruction, or oliguria or anuria alternating with polyuria. [merckmanuals.com]

Urinary tract obstruction is a known risk factor for the development of both acute and chronic kidney disease, especially in children [4], which may have devastating long-term consequences in the absence of an early diagnosis. For this reason, physicians must conduct a thorough clinical workup, starting with a detailed patient history that will assess the presenting signs and symptoms and reveal preexisting disorders or events that might have caused obstruction [2]. In addition, a meticulous physical examination, with an emphasis on abdominal and genital inspection, palpation and percussion, is necessary to raise valid suspicion [2]. Urinalysis is one of the first laboratory studies that can be performed, and often shows hematuria and bacteriuria [5]. In addition, a full laboratory workup comprised of serum electrolytes, a complete blood count (CBC) and renal function tests must be carried out. Serum creatinine and blood urea nitrogen (BUN) are both high in acute obstruction, in which case imaging studies should be employed to identify the cause. If obstruction at the level of the urethra is suspected, either cystourethroscopy or voiding cystourethrography is recommended, whereas abdominal ultrasonography and computed tomography (CT) are used if hydronephrosis or ureteral obstruction might be present [5] [6]. If ultrasound and CT are not conclusive, urography or pyelography (anterograde or retrograde) is indicated [5] [6]. Several biochemical markers have been proposed as potentially useful indicators of obstructive uropathy and its severity (kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin, or KIM-1 and NGAL, but also several other), although further studies are required to solidify their place in general practice [4].

• Ventricular Hypertrophy

  RESULTS: In the LUTO group an increased cardiothoracic ratio was seen in nine (21%), ventricular hypertrophy in 12 (29%) and small pericardial effusion in 15 (36%). [ncbi.nlm.nih.gov]

1. Chevalier RL. Congenital Urinary Tract Obstruction: The Long View. Advances in chronic kidney disease. 2015;22(4):312-319.
2. Dmochowski RR. Bladder Outlet Obstruction: Etiology and Evaluation. Reviews in Urology. 2005;7(Suppl 6):S3-S13.
3. Bascands J-L, Schanstra JP. Obstructive nephropathy: insights from genetically engineered animals. Kidney International. 2005;68(3):925-937.
4. Wasilewska A, Taranta-Janusz K, Dębek W, Zoch-Zwierz W, Kuroczycka-Saniutycz E. KIM-1 and NGAL: new markers of obstructive nephropathy. Pediatr Nephrol. 2011;26(4):579-586.
5. Kasper DL, Fauci AS, Hauser SL, Longo DL, Jameson J, Loscalzo J. eds. Harrison's Principles of Internal Medicine, 19e. New York, NY: McGraw-Hill; 2016.
6. Porter RS, Kaplan JL. Merck Manual of Diagnosis and Therapy. 19th Edition. Merck Sharp & Dohme Corp. Whitehouse Station, N.J; 2011.