Rigors and a loin that will not be touched

A 52-year-old arrives shaking, febrile, and guarding her left flank from the examining hand.

52-year-old womanED, bay 1Fictitious educational patient

Type 2 diabetesA 'kidney stone that passed by itself' five years ago

Day 0 · 20:30

Arrival

Two days of left loin pain, then this evening a rigor that shook the bed. She has vomited four times and cannot find a comfortable position. The triage dipstick shows blood, leukocytes, and nitrites.

Vitals

HR124BP96/58RR24SpO296%T39.4

Examination

Abdomen: Exquisite left costovertebral angle tenderness; abdomen otherwise soft.
General: Shivering, flushed, dry mucous membranes.

Febrile, hypotensive, infective urine, and a UNILATERAL painful loin with a stone history. What must this presentation make you exclude urgently?

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