Epididymitis is a common cause of acute scrotal pain in adolescents and adults.[10]American College of Radiology. ACR appropriateness criteria: acute onset of scrotal pain-without trauma, without antecedent mass. 2024 [internet publication].
https://acsearch.acr.org/docs/69363/Narrative
Data on the incidence and prevalence of acute epididymitis are, however, limited.
In one study of patient encounters at a US emergency department, 1.3% of men were diagnosed with epididymitis, orchitis, or both conditions over a 3-year period.[11]Bonner M, Sheele JM, Cantillo-Campos S, et al. A descriptive analysis of men diagnosed with epididymitis, orchitis, or both in the emergency department. Cureus. 2021 Jun;13(6):e15800.
https://pmc.ncbi.nlm.nih.gov/articles/PMC8294204
http://www.ncbi.nlm.nih.gov/pubmed/34306868?tool=bestpractice.com
One 2005 study in Canada showed that 0.9% of men seen at an outpatient practice over a 2.5-year period presented with epididymitis.[12]Nickel JC, Teichman JM, Gregoire M, et al. Prevalence, diagnosis, characterization, and treatment of prostatitis, interstitial cystitis, and epididymitis in outpatient urological practice: the Canadian PIE Study. Urology. 2005 Nov;66(5):935-40.
http://www.ncbi.nlm.nih.gov/pubmed/16286098?tool=bestpractice.com
In a study in the UK, the reported annual incidence was 2.45 cases per 1000 men between 2003 and 2008.[13]Nicholson A, Rait G, Murray-Thomas T, et al. Management of epididymo-orchitis in primary care: results from a large UK primary care database. Br J Gen Pract. 2010 Oct;60(579):e407-22.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2944950
http://www.ncbi.nlm.nih.gov/pubmed/20883615?tool=bestpractice.com
Another study in boys, undertaken in Europe, estimated the annual incidence of epididymitis at 1.2 per 1000 male children.[14]Somekh E, Gorenstein A, Serour F. Acute epididymitis in boys: evidence of a post-infectious etiology. J Urol. 2004 Jan;171(1):391-4.
http://www.ncbi.nlm.nih.gov/pubmed/14665940?tool=bestpractice.com
Epididymitis may present at any age, with the majority of patients aged 20 to 39 years.[15]Tracy CR, Steers WD, Costabile R. Diagnosis and management of epididymitis. Urol Clin North Am. 2008 Feb;35(1):101-8;vii.
http://www.ncbi.nlm.nih.gov/pubmed/18061028?tool=bestpractice.com
The majority of cases of epididymitis in children occur around the time of puberty in early adolescence.[16]Redshaw JD, Tran TL, Wallis MC, et al. Epididymitis: a 21-year retrospective review of presentations to an outpatient urology clinic. J Urol. 2014 Oct;192(4):1203-7.
http://www.ncbi.nlm.nih.gov/pubmed/24735936?tool=bestpractice.com