The physical sign of spinal cord compression is a sensory level, but this tends to occur late in the day in the course of the condition. Remember, however, that a normal neurological examination does not exclude a diagnosis of cord compression. If, on the basis of the patient's symptoms, you suspect cord compression, arrange for a magnetic resonance imaging (MRI) scan without delay.
Malignant infiltration of retroperitoneal lymph nodes by, for example, testicular cancers or lymphoma can also cause back pain.
As a general rule, if a patient presents with bizarre symptoms that are difficult to explain, consider the possibility of a neurological cause.
Khadra MH, Pickard RS, Charlton M, et al. A prospective analysis of 1,930 patients with hematuria to evaluate current diagnostic practice. J Urol 2000;163:524-527.
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Smith RC, Verga M, McCarthy S, Rosenfield AT. Diagnosis of acute flank pain: value of unenhanced helical CT. AJR 1996;166:97-101.
Thomson JM, Glocer J, Abbott C, et al. Computed tomography versus intravenous urography in diagnosis of acute flank pain from urolithiasis: a randomized study comparing imaging costs and radiation dose. Australas Radiol 2001;45:291-297.
Lower Urinary Tract Emergencies
ACUTE URINARY RETENTION
Painful inability to void, with relief of pain following drainage of the bladder by catheterisation.
The combination of reduced or absent urine output with lower abdominal pain is not in itself enough to make a diagnosis of acute retention. Many acute surgical conditions cause abdominal pain and fluid depletion, the latter leading to reduced urine output, and this reduced urine output can give the erroneous impression that the patient is in retention, when in fact they are not. Thus, central to the diagnosis is the presence of a large volume of urine, which when drained by catheterisation, leads to resolution of the pain. What represents 'large' has not been strictly defined, but volumes of 500 to 800 mL are typical. Volumes <500mL should lead one to question the diagnosis. Volumes >800mL are defined as acute-on-chronic retention (see Is It Acute or Chronic Retention? below).