My 70 year old male patient is admitted with 1 day of fever, dysuria, and urinary frequency and urgency, but has a negative urine dipstick test for nitrites and leukocyte esterase. Could he still have acute bacterial prostatitis?

Short answer: Yes! In fact, no routine clinical imaging test can adequately rule out prostatic involvement in men with urinary tract infection (UTI) symptoms (1)! 

Although the presence of nitrites and leukocyte esterase (LE) may have a high positive predictive value for acute bacterial prostatitis (ABP) (~95%), their combined absence has a negative predictive value of only ~70%; ie, we may miss about one-third of patients with UTI symptoms if we relied solely on the results of nitrite and LE urine dipstick (2,3). Negative nitrites alone has a negative predictive value of only ~ 45%, while a negative LE has a negative predictive value of ~60% (3).

To evaluate for ABP, our patient should undergo rectal exam for prostatic tenderness, as should all men with UTI symptoms. The finding of a tender prostate in this setting is supportive of ABP, although its absence will still not rule out this diagnosis because the reported sensitivity of rectal exam may vary from 9% to 100% in ABP (1). 
Although there may not be a general agreement on the definition of ABP, 2 studies utilizing indium-labeled leukocyte scintigraphy or a combination of PSA levels and transrectal ultrasound have provided evidence for frequent prostatic involvement in men with UTI symptoms (4,5).  In these studies, an inflammatory reaction within the prostate was seen in the majority of cases, even when the digital rectal examination was not painful or when clinicians diagnosed pyelonephritis without prostatitis.
Bonus pearl: Did you know that the lifetime probability of a man receiving a diagnosis of prostatitis is >25% (1)? 

Also see a related P4P pearl: https://pearls4peers.com/2017/07/27/should-male-patients-with-suspected-urinary-tract-infection-routinely-undergo-a-prostate-exam/

 

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References
1. Etienne M, Chavanet P, Sibert L, et al. Acute bacterial prostatitis: heterogeneity in diagnostic criteria and management. Retrospective multicentric analysis of 371 patients diagnosed with acute prostatitis. BMC Infect Dis 2008, 8:12 doi:10.1186/1471-2334-8-12. https://bmcinfectdis.biomedcentral.com/articles/10.1186/1471-2334-8-12
2. Lipsky BA, Byren I, Hoey CT. Treatment of bacterial prostatitis. Clin Infect Dis 2010;50:1641-1652. https://academic.oup.com/cid/article/50/12/1641/305217
3. Etienne M, Pestel-Caron M, Chavanet P, et al. Performance of the urine leukocyte esterase and nitrite dipstick test for the diagnosis of acute prostatitis. Clin Infect Dis 2008; 46:951-53. https://academic.oup.com/cid/article/46/6/951/351423
4. Velasco M, Mateos JJ, Martinez JA, et al. Accurate topographical diagnosis of urinary tract infection in male patients with (111)indium-labelled leukocyte scintigraphy. Eur J Intern Med 2004;15:157-61. https://www.ncbi.nlm.nih.gov/pubmed/15245717
5. Ulleryd P, Zackrisson B, Aus G, et al. Prostatic involvement in men with febrie urinary tract infection as measured by serum prostate-specific antigen and transrectal ultrasonography. BJU Int 1999;84:470-74. https://onlinelibrary.wiley.com/doi/full/10.1046/j.1464-410x.1999.00164.x

 

My 70 year old male patient is admitted with 1 day of fever, dysuria, and urinary frequency and urgency, but has a negative urine dipstick test for nitrites and leukocyte esterase. Could he still have acute bacterial prostatitis?

Should male patients with suspected urinary tract infection routinely undergo a prostate exam?

Yes! That’s because any urinary tract infection (UTI) in men has the potential for prostatic involvement1 —-as high as 83% by one report. 2  

To make the matters more confusing, patients with acute bacterial prostatitis (ABP) often present with symptoms just like those of UTI,  such as urinary frequency, dysuria, malaise, fever, and myalgias. 3  In the elderly, atypical presentation is not uncommon (eg, confusion, incontinence, fall). 4  Under these circumstances, bacteriuria and pyuria may also be related to ABP and the prostate exam should be an important part of your evaluation.

Although the sensitivity of prostate tenderness on digital rectal exam varies widely for ABP (9%-100%), a painful exam should raise suspicion for ABP, and by itself may be an independent predictor for clinical and bacteriologic failure of therapy. 1 Along with tenderness, fluctuance of prostate, particularly in the setting of voiding difficulties and longer duration of symptoms, may also suggest the presence of prostatic abscess. 5,6 

But be gentle when performing a prostate exam and don’t massage it because you could potentially cause bacteremia and worsening of sepsis! 1,7

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References

  1. Etienne M, Chavanet P, Sibert L, et al. Acute bacterial prostatitis: heterogeneity in diagnostic criteria and management. Retrospective multicentric analysis of 371 patients diagnosed with acute prostatitis. BMC Infectious Diseases 2008;8:12. https://bmcinfectdis.biomedcentral.com/track/pdf/10.1186/1471-2334-8-12?site=bmcinfectdis.biomedcentral.com
  2. Ulleryd P, Zackrisson B, Aus G, et al. Prostatic involvement in men with febrile urinary tract infection as measured by serum prostate-specific antigen and transrectal ultrasonography. BJU Int 1999;84:470-4. http://onlinelibrary.wiley.com/doi/10.1046/j.1464-410x.1999.00164.x/pdf
  3. Krieger JN, Nyberg L, Nickel JC. NIH consensus definition and classification. JAMA 1999;282:236-37. http://jamanetwork.com/journals/jama/article-abstract/1030245
  4. Harper M, Fowlis. Management of urinary tract infections in men. Trends in Urology Gynaecology & Sexual Health. January/February 2007. http://onlinelibrary.wiley.com/doi/10.1002/tre.8/pdf
  5. Lee DS, Choe HS, Kim HY, et al. Acute bacterial prostatitis and abscess formation. BMC Urology 2016;16:38. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4936164/
  6. Oliveira P, Andrade JA, Porto HC, et al. Diagnosis and treatment of prostatic abscess. International Braz J Urol 2003;29: 30-34. http://www.scielo.br/pdf/ibju/v29n1/v29n1a06.pdf
  7. Lipsky BA, Byren I, Hoey CT. Treatment of bacterial prostatitis. Clin Infect Dis 2010; 50:1641-52. https://academic.oup.com/cid/article/50/12/1641/305217

 

Should male patients with suspected urinary tract infection routinely undergo a prostate exam?

How exactly do urinary tract infections (UTIs) cause delirium in my elderly patients?

 UTIs are often considered in the differential diagnosis of causes of delirium in the elderly. Though largely speculative, 2 possible pathophysiologic basis for this association are suggested:1-3

  •  Direct brain insult (eg, in the setting of sepsis/hypotension)
  • Indirect aberrant stress response, involving cytokines/inflammatory pathways,  hypothalamic-pituitary-adrenal [HPA] axis and sympathetic nervous system (SNS). One or both pathways can interact with the neurotransmitter and intracellular signal transduction systems underlying delirium in the brain, which may already be impaired in the elderly due to age-related or other pathologic changes.

The indirect aberrant stress pathway suggests that not only pain and discomfort (eg from dysuria) can contribute to delirium but UTI-associated circulating cytokines may also cause delirium.  Indeed, a large study of older adults undergoing elective surgery found a significant association between delirium postoperatively (postop day 2) and serum proinflammatory cytokine levels such as IL-6. 4  

The corollary is that bacteriuria is unlikely to be associated with delirium in the absence of significant systemic inflammatory response, pain or discomfort.

 

References

1.Trzepacz P, van der Mast R. The neuropathophysiology of delirium. In Lindesay J,  Rockwood K, Macdonald A (Eds.). Delirium in old age, pp. 51–90. Oxford University Press, Oxford , 2002.

2.Flacker JM, Lipsitz LA. Neural mechanisms of delirium: current hypotheses and evolving concepts. J Gerontol A Biol Sci Med Sci. 1999; 54: B239–B246 https://www.ncbi.nlm.nih.gov/pubmed/10411009

3. Maclullich AM, Ferguson KJ, Miller T, de Rooij SE, Cunningham C. Unravelling the pathophysiology of delirium: a focus on the role of aberrant stress responses. J Psychosom Res. 2008;65:229–38. https://www.ncbi.nlm.nih.gov/pubmed/18707945

4. Vasunilashom SM, Ngo L, Inouye SK, et al. Cytokines and postoperative delirium in older patients undergoing major elective surgery. J Gerontol A Biol Sci Med Sci 2015;70:1289-95. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4817082/pdf/glv083.pdf

Contributed by Henrietta Afari MD, Mass General Hospital, Boston, MA

How exactly do urinary tract infections (UTIs) cause delirium in my elderly patients?