Flank pain
The diagnoses shown in bold in Figure 18.1 are all surgical emergencies that you must exclude as you clerk the patient. In women, you should consider gynaecological causes, e.g. ectopic pregnancy, ovarian torsion (you can of course narrow these down depending on whether the woman is of childbearing age or not). Also, bear in mind that other abdominal pathology can occasionally present as flank pain (e.g. pancreatitis, diverticulitis, appendicitis). You should ask the standard array of questions about the pain—remember the mnemonic SOCRATES: Site: Where is the pain, and has it always been there? Is it unilateral or bilateral? Kidney stones are almost always unilateral, but the location of the pain may radiate from loin to groin. Often they start with a vague discomfort that is ignored until it becomes a severe pain. Onset: Any trauma or other trigger, or spontaneous? Gradual or sudden? Trauma may lead to musculoskeletal pain or internal bleeding. Character: Is the pain colicky or constant? Is it sharp or dull? Ureteric stones give a colicky (waxing and waning) pain because of periodic spasms of the ureteric smooth muscle walls trying to dislodge the blockage. A constant pain is more consistent with a stone lodged in the kidney, which does not periodically contract (‘vermiculate’) like the ureters, or an inflammatory cause. Musculoskeletal pain is more typically an ache, while nerve impingement causes shooting pains. Radiation: Does the pain radiate to the groin (typical of ureteric pain)? Does it radiate down the leg (typical of lumbar nerve root pain)? Alleviating factors: Does anything make the pain better, e.g. a given posture, eating/drinking, any medications, etc.? Timing: How long has the pain been present? Musculoskeletal back pain can last many weeks, whereas a leaking abdominal aortic aneurysm (AAA) is unlikely to persist for more than a day without resolution, one way or another. Exacerbating factors: Does anything make the pain worse? Patients with peritonitis (e.g. due to a perforated peptic ulcer) are very sensitive to movement. Severity: How severe is the pain (e.g. on a scale of 1–10)? Kidney stones are said to be excruciatingly painful, comparable to childbirth.