The point, then, in making a diagnosis is to exclude other causes of flank pain, many of which are serious and may be life-threatening (leaking aortic aneurysm, gastrointestinal causes,
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medical causes), from those cases where the pain is due to a ureteric stone, which is very rarely life-threatening.
Age of the patient can help in determining whether a diagnosis of a ureteric stone is more or less likely. Ureteric colic tends to be a disease of men (and to a lesser extent women) between the ages of roughly 20 and 60. It does affect younger and older patients, but the range of differential diagnoses at the extremes of age, and in women, is greater. Thus, a 25-year-old man who presents with sudden onset of severe, colicky flank pain probably has a ureteric stone, but an 80-year-old woman probably has something else going on.
Examination and Simple Tests
The pain from a ureteric stone is colicky in nature. It makes the patient want to move around, in an attempt to find a comfortable position. The patient may be doubled-up with pain. On the other hand, patients with conditions causing peritonitis, such as appendicitis or a ruptured ectopic pregnancy, want to lie very still. Any movement is very painful and in particular they do not like palpation of their abdomen. Thus, when you approach patients, just spend a few seconds looking at them. If they are lying very still, you may be dealing with a non-stone cause of flank pain.
All premenopausal women with acute flank pain should undergo a pregnancy test. If this is positive, they are referred to a gynaecologist. If it is negative, they should undergo imaging to determine whether or not they have a ureteric stone. It goes without saying that any premenopausal woman who is going to undergo imaging using ionising radiation, should have a pregnancy test done first.
Dipstick or Microscopic Haematuria
While many patients with ureteric stones have dipstick or microscopic haematuria (and more rarely macroscopic haematuria), 10% to 30% of such patients have no blood in their urine (Kobayashi et al. 2003, Luchs et al. 2002). There is evidence that if a stone has been present in the ureter for 3 to 4 days, there is a greater likelihood that haematuria will not be detectable.