Brief Answer:
Most possibly a Renal cause.

Detailed Answer:
Hi, thanks for writing to XXXXXXX

Flank pain (located below the ribs and above the pelvis and on the side) is most often a sign of kidney disease though it is seen in many other conditions.

Sudden onset of loin pain along with nausea is highly suggestive of a Renal Calculi (kidney stone). As your husband is also a Gout patient (as per the medical history), I suspect he could be suffering from Uric acid stones in the kidney. There may not be always burning micturition as this symptom depends upon the site of stone obstruction in the urinary tract.

An Ultrasound examination of the abdomen or an MRI scan helps in establishing the diagnosis.

I suggest you to consult a General surgeon or Urologist for further workup and management.

Hope I have addressed your query. I welcome any clarification

Regards

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