What’s the diagnosis for this male patient’s pain and swelling?
A 28-year-old male presents for evaluation of severe left testicle pain and swelling that developed over the past two days. Vital signs are unremarkable. On exam, his left testicle is tender, but with normal lie. The right testicle is unremarkable. The scrotum is generally painful and edematous. He has no cremasteric reflex on either side. Urinalysis shows 57 WBC/hpf and 14 RBC/hpf. Which of the following is the most likely diagnosis?
- Inguinal hernia
- Testicular torsion
Correct answer: A. Epididymitis
Epididymitis is the most common intrascrotal infection. It is most commonly caused by direct extension of urethral bacteria, likely from a sexually transmitted infection in younger males (namely N. gonorrhoeae and C. trachomatis). In older men, urinary pathogens are more likely (e.g., E. coli). Heavy physical exertion, direct trauma and sexual activity are known risk factors.
Diagnosis is based on pyuria and bacteriuria; testicular ultrasound can be confirmatory and is commonly performed to rule out testicular torsion. Ultrasound will often show increased blood flow to the testicle in question in the presence of epididymitis, a helpful contrast to the decreasedor absent flow in torsion. Classically Prehn’s sign (relief of pain with scrotal elevation) was taught as being suggestive of epididymitis. However, it is neither sufficiently sensitive nor specific for clinical use, but has excellent efficacy for writing test questions. (A “positive” Prehn’s sign is relief of pain with scrotal elevation and suggestive of epididymitis, if anyone asks…)
Treatment is with ceftriaxone IM x1 and doxycycline 100mg BID x10 days in younger males in whom an STI is suspected as the etiology; treatment is levofloxacin or ofloxacin in older males in whom enteric organisms are suspected. TMP-SMX is sometimes used, based on local resistance patterns, but is not part of the 2015 CDC guidelines. Sexually active males who practice receptive intercourse should be treated for both broad causes by ceftriaxone IM x1 and [levofloxacin x10 days or ofloxacin x10 days]. Epididymitis in infants is also more likely to be caused by urinary pathogens and can be treated with cephalexin TID.
Incorrect answer choices:
Testicular torsion (Choice D) must be evaluated in every male who presents for evaluation of acute scrotal pain (and lower abdominal pain), and it would be reasonable to obtain an ultrasound if offered as an answer choice. However, by history and exam findings, this is more likely epididymitis. Testicular torsion tends to present acutely with sudden onset severe pain that may be intermittent (in the same way that ovarian torsion can be intermittent).
Cremasteric reflex might be absent, but that is nonspecific, and the vignette mentions that cremasteric reflexes are absent on both sides to indicate that it should not be used to rule testicular torsion in or out. In terms of highest incidence, testicular torsion is more likely in the first year of life and during puberty, whereas epididymitis is more prevalent in adulthood. Treatment for testicular torsion is initially manual detorsion (“open the book”) followed immediately thereafter by surgical detorsion and potentially orchiectomy.
Pain related to ureterolithiasis (Choice E) can present with testicular pain; however, the UA usually shows blood without pyuria. The exception, of course, is an infected stone. Pain onset for kidney stones is also more classically described as sudden onset, in contrast to the slowly progressive nature of pain described in this vignette. Additionally, ureterolithiasis does not cause scrotal edema. Diagnosis is with a renal ultrasound, KUB (less often) or noncontrast CT scan of the abdomen and pelvis.
Prostatitis (Choice C) classically presents with rectal pain and often dysuria, but the scrotal exam is normal. Similar to epididymitis, prostatitis is more commonly caused by STIs in younger men and enteric organisms in older men. The treatment is slightly different in that levofloxacin or ciprofloxacin are recommended. Ceftriaxone and TMP-SMX are also options but not first-line because of pharmacokinetic properties that do not deliver the drugs as well to the prostate.
Patients with inguinal hernias (Choice B) can complain of testicular pain, but usually the UA is normal, and the scrotum is not erythematous. Inguinal hernias are more common in men than women, with a bimodal age distribution in newborns and after age 55. Direct inguinal hernias violate the wall of the inguinal canal, passing directly through the facial structures of the abdomen. Indirect (most common type) inguinal hernias exit through the inguinal canal. Direct and indirect are not discernible clinically.