From a previous Post…..
A 60-year old man leaves home with the hint of an impending UTI. Pre-emptively he started a course of antibiotics from a repeat left over from a previous successfully treated UTI. He travels across Australia gradually getting worse. He stops for advise at a mainland country hospital. There he is given the diagnosis of pyelonephritis treated with oral antibiotics and analgesia. Shortly after arriving on KI he presented to quite unwell, febrile, tachycardic and dehydrated with marked left abdominal pain. My working diagnosis was diverticulitis and I admitted him, hoping that he would settle with IV antibiotics and not require a journey with the flying doctor to Adelaide. Two days latter with CRP risen from 60 to 220, rising creatinine, still requiring morphine for his pain, bowels not open, with no blood in his urine, he is transferred to the care of a friendly surgical registrar at a big teaching hospital. A CT scan revealed a large mid-uretric stone, hydronephrosis and perinephric stranding. He was stented 2 days latter by urology registrar who happily told me 30% of patient with stones don’t have blood in their urine!!
Okay so what can I learn.
Oxford Handbook of Clinical Medicine suggests that a mid-uretetic renal stone may mimic diverticulitis.
Through the mists of time I had accepted that if you don’t have blood in the urine then you can’t have a kidney stone.
Maybe I have been prejudiced by the ED mantra
“moaning & groaning drug seeker, no blood in the urine, cant be renal colic, no opiates for you, just a paracetamol & indomethacin suppository….. oh, your leaving are you?”
So is my friendly urology registrar right?
To quote Up To Date (add the American accent)
“On the other hand, the absence of hematuria in the setting of acute flank pain does not exclude the presence of nephrolithiasis. Hematuria is not detected in approximately 10 to 30 percent of patients with documented nephrolithiasis. One factor that may undermine the sensitivity of hematuria is the interval from the onset of acute pain to the time of urine examination. In a retrospective study of over 450 patients with CT-documented acute ureterolithiasis, hematuria was present in 95 percent on day one and 65 to 68 percent on days three and four.”
Press and Smith reviewed 140 patients who presented with flank pain to their emergency department from January 1, 1992, through December 31, 1992, and underwent intravenous urogram. No haematuria was found in 14.5% of patient proven to have stones. They also found that by considering a negative combination (urinalysis plus urine dipstick test) as a new definition of negative hematuria, the incidence of negative hematuria in patients with acute stones was only 5.5% (P < 0.031). Press SM, Smith AD. Incidence of negative hematuria in patients with acute nephrolithiasis presenting to the emergency room with flank pain. Urology. 1995;45(5):753.
Bove et al reviewed the medical records of 267 consecutive patients with acute flank pain referred for unenhanced helical CT. Microscopic and dipstick urinalysis data were obtained in 195 patients. Using helical CT as the gold standard, we calculated the sensitivity, specificity, predictive value and accuracy of hematuria for diagnosing ureterolithiasis. Of the patients with ureterolithiasis 33% had 5 or less, 19% had 1 or less and 11% had no red blood cells per high power field. Bove P, Kaplan D, Dalrymple N, Rosenfield AT, Verga M, Anderson K, Smith RC. Reexamining the value of hematuria testing in patients with acute flank pain. J Urol. 1999;162(3 Pt 1):685.