eMedicine Specialties > Emergency Medicine > Genitourinary

Epididymitis

Catherine Tubridy, MD, Staff Physician, Combined Residency Program for Emergency Medicine and Internal Medicine, State University of New York Downstate/Kings County Hospital Centers
Richard Sinert, DO, Associate Professor of Emergency Medicine, Clinical Assistant Professor of Medicine, Research Director, State University of New York College of Medicine; Consulting Staff, Department of Emergency Medicine, Kings County Hospital Center

Updated: Sep 4, 2008

Introduction

Background

The epididymis is a coiled tubular structure located along the posterior aspect of the testis. It allows for the storage, maturation, and transport of sperm, connecting the efferent ducts of the testis to the vas deferens. Inflammation of the epididymis can be acute (<6 wk) or chronic and is most commonly caused by infection.

Under Investigation

Pathophysiology

Epididymitis most often is due to the retrograde extension of organisms from the vas deferens and is rarely the result of hematogenous spread. Bacterial infection results in the infiltration of white blood cells into the epididymal connective tissue, with resultant congestion and edema. This inflammation can rapidly spread to the tubules, with the risk of abscess formation and necrosis of the epididymis.^3,4 The causative organism is identified in 80% of patients and varies according to the age of the patient.

In prepubertal males, the predominating sources are pathogens that cause bacteriuria (ie, coliform bacteria [Escherichia coli]). Workup should include a urologic evaluation for a genitourinary anomaly, which is present in as many as 50% of these patients.^5,6 Epididymitis in this age group may also be secondary to a postinfectious inflammatory reaction to certain pathogens. Research has shown that boys with epididymitis had significantly elevated titers for Mycoplasma pneumoniae, enteroviruses, and adenoviruses when compared with control groups.⁷

In sexually active men (age 35 years has frequently been used as a parameter in research studies), the predominating sources are Chlamydia trachomatis and Neisseria gonorrhoeae, with C trachomatis being responsible for nearly two thirds of all cases. In homosexual men younger than 35 years, coliform bacteria are highly represented.

Frequency

United States

Epididymitis is the most common cause of intrascrotal inflammation. Incidence is less than 1 case in 1,000 males per year.

Mortality/Morbidity

Infection of the epididymis can lead to the formation of an epididymal abscess. In addition, progression of the infection can lead to involvement of the testicle, causing epididymo-orchitis or a testicular abscess. Sepsis is a potential consequence of severe infection. Bilateral epididymitis may result in sterility due to occlusion of the ductules from peritubular fibrosis.

• Patients with epididymitis secondary to a sexually transmitted disease have 2-5 times the risk of acquiring and transmitting the human immunodeficiency virus.⁸
• All sexual partners of patients with epididymitis secondary to a sexually transmitted disease need referral to ensure that they receive adequate testing and treatment.

Age

Epididymitis is primarily a disease of adults, most commonly affecting males aged 19-40 years.

Clinical

History

The progression of epididymitis usually is gradual in nature, with symptoms often peaking within 24 hours of onset. Initially, the patient may note abdominal or flank pain because cellular inflammation typically begins in the vas deferens. As the inflammation descends to the lower segment of the epididymis, the patient notes discomfort localized to the scrotum. Younger patients or any patient with a sexually transmitted epididymitis may note symptoms related to urethritis. A recent history of endourethral instrumentation or urinary tract infection is more common in older patients. Symptoms include the following:

• Scrotal pain and edema
• Urinary frequency, urgency, or dysuria
• Urinary retention from bladder outlet obstruction in older patients
• Nausea
• Fever and chills
• Abdominal or flank pain
• Bilateral epididymal involvement (10%)
• Urethral discharge

Physical

• Edematous tender epididymis: Early on, in cases without significant testicular involvement, tenderness may be clearly localized to the epididymis.
• Erythematous edematous scrotum
• Scrotal abscess
  • Scrotal fluctuance
  • Scrotal fixation to underlying epididymis
• Reactive hydrocele
• Prehn sign has been used to distinguish epididymitis from testicular torsion. Classically, scrotal elevation decreases pain in epididymitis and not in torsion. However, the Prehn sign is not reliable for distinguishing epididymitis from testicular torsion.
• Urethral discharge (10%)
• Fever or other constitutional symptoms with progression of disease

Causes

• Epididymitis most often is due to the retrograde extension of bacterial organisms from the vas deferens.
  • Prepubertal males - Coliform bacteria (E coli)
  • Sexually active males -C trachomatis is the most common organism followed by N gonorrhoeae
  • Older males - Coliform bacteria most common, sexually transmitted diseases (STDs) less common
• Less common causes of epididymitis include the following:
  • Chemical epididymitis due to the reflux of sterile urine
  • Boys with epididymitis due to a postinfectious inflammatory reaction to pathogens, such as Mycoplasma pneumoniae, enteroviruses, and adenoviruses
  • Candidal epididymitis in immunocompromised patients (AIDS)
  • Epididymitis as an extrapulmonary manifestation of tuberculosis
  • Epididymitis secondary to exposure to amiodarone therapy or prostate brachytherapy

Differential Diagnoses

Hydrocele
Orchitis
Testicular Torsion
Urinary Tract Infection, Male

Other Problems to Be Considered

Epididymal cyst
Epididymal congestion following vasectomy
Spermatocele
Testicular tumor (hemorrhage into tumor)
Varicocele

Workup

Laboratory Studies

The following laboratory studies may be indicated for suspected epididymitis:

• Urinalysis - Pyuria or bacteriuria (50%); urine culture indicated for prepubertal and elderly patients
• CBC - Leukocytosis
• Gram stain of urethral discharge, if present
• Urethral culture, nucleic acid hybridization, and nucleic acid amplification tests (These tests aid in detection of N gonorrhoeae and C trachomatis.)
• Performance of (or referral for) syphilis and HIV testing in patients with a sexually transmitted etiology
• The utility of CRP and ESR to differentiate epididymitis from other causes of acute scrotum is currently being studied. See Under Investigation.

Imaging Studies

• Imaging studies are often used to differentiate the more common epididymitis from testicular torsion. However, clinical judgment must guide interpretation of imaging results, as they are neither 100% sensitive or specific. Refer to the article Testicular Torsion.
• Radionuclide scintigraphy
  • Radionuclide scintigraphy is used to assess testicle perfusion, yet it provides little anatomic information.
  • Decreased perfusion suggests torsion. Increased or normal perfusion suggests epididymitis but also may be reported with actual torsion.
• Color-coded Doppler ultrasonography
  • This type of ultrasonography assesses perfusion of the testicle and anatomy of the scrotal contents.
  • A normal testicle with markedly diminished Doppler wave pulsation represents torsion.
  • A thickened enlarged epididymis with increased Doppler wave pulsation represents epididymitis.
  • The accuracy of the emergency physician to diagnose acute scrotal pain is being studied. See Under Investigation.

Procedures

• Scrotal exploration or aspiration of epididymis (rarely needed and performed by a urologist)

Treatment

Emergency Department Care

Patients with testicle or scrotal pain require immediate evaluation in order to identify and quickly treat potential cases of testicular torsion. Although most cases of torsion occur in patients aged 12-18 years, testicular torsion should be considered in any patient aged 12-30 years who presents with a scrotal complaint.

• Obtain immediate urologic consultation if unable to clearly differentiate testicular torsion from epididymitis or other scrotal pathology.
• Antibiotic therapy
• Analgesics for pain control
• Supportive care
  • Scrotal elevation and support
  • Ice pack
  • Spermatic cord block (possibly)

Consultations

Consult a urologist immediately if torsion is a possibility. Testicular torsion is a clinical diagnosis, and consultation should not be delayed for the performance of additional ancillary studies. Otherwise, most cases of epididymitis can be managed on an outpatient basis with follow-up with a urologist scheduled within 3-7 days. All pediatric cases of epididymitis require immediate consultation because of the high incidence of associated genitourinary anomalies.

Medication

Antibiotics should be used in all cases of epididymitis, regardless of a negative urinalysis or the urethral Gram stain result. Nonsteroidal anti-inflammatory agents or narcotic analgesics also generally are prescribed to patients with epididymitis.

Antibiotics

Empiric coverage varies with the patient's age and sexual history.

Prepubertal patients and older men require empiric coverage for coliform bacteria (enteric gram-negative bacilli or Pseudomonas). Both of these patient populations may be treated with trimethoprim sulfamethoxazole (TMP-SMZ). 

Sexually active men need empiric coverage for C trachomatis and N gonorrhoeae, usually with ceftriaxone and doxycycline or azithromycin.  

Fluoroquinolones are no longer recommended to treat gonorrhea in the United States. This recommendation was based on an analysis of data from the CDC's Gonococcal Isolate Surveillance Project (GISP). The data from GISP shows an 11-fold increase in the proportion of fluoroquinolone-resistant gonorrhea (QRNG) in heterosexual men, increasing from 0.6% in 2001 to 6.7% in 2006.⁹ This limits treatment of gonorrhea to drugs in the cephalosporin class. Fluoroquinolones may be an alternative treatment option for disseminated gonococcal infection if antimicrobial susceptibility can be documented.

Ceftriaxone (Rocephin)

Third-generation cephalosporin that has broad gram-negative spectrum, lower efficacy against gram-positive organisms, and higher efficacy against resistant organisms.
By binding to one or more of the penicillin-binding proteins, it arrests bacterial cell wall synthesis and inhibits bacterial growth.

Dosing

Adult

250-1000 mg IM once

Pediatric

Infants and children: 50-75 mg/kg/d IV divided q12h; not to exceed 2 g/d

Interactions

Probenecid may increase ceftriaxone levels; coadministration with ethacrynic acid, furosemide, and aminoglycosides may increase nephrotoxicity

Contraindications

Documented hypersensitivity

Precautions

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

Precautions

Adjust dose in renal impairment; caution in breastfeeding women and those allergic to penicillin

Doxycycline (Bio-Tab, Doryx, Vibramycin)

Inhibits protein synthesis and bacterial growth by binding with the 30S and, possibly, the 50S ribosomal subunits of susceptible bacteria.

Dosing

Adult

100 mg PO bid for 10-14 d

Pediatric

<8 years: Not recommended
>8 years: 2-5 mg/kg/d in 1-2 divided doses; not to exceed 200 mg/d

Interactions

Bioavailability decreases with antacids containing aluminum, calcium, magnesium, iron, or bismuth subsalicylate; tetracyclines can increase hypoprothrombinemic effects of anticoagulants; tetracyclines can decrease effects of oral contraceptives, causing breakthrough bleeding and increased risk of pregnancy

Contraindications

Documented hypersensitivity; severe hepatic dysfunction

Precautions

Pregnancy

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

Photosensitivity may occur with prolonged exposure to sunlight or tanning equipment; reduce dose in renal impairment; consider drug serum level determinations in prolonged therapy; tetracycline use during tooth development (last one half of pregnancy through age 8 y) can cause permanent discoloration of teeth; Fanconilike syndrome may occur with outdated tetracyclines

Azithromycin (Zithromax)

Used to treat mild-to-moderate infections caused by susceptible strains of microorganisms. Indicated for chlamydial and gonorrheal infections of the genital tract.

Dosing

Adult

1 g PO once

Pediatric

<6 months: Not established
>6 months: 10 mg/kg PO day 1; 5 mg/kg PO qd days 2-5

Interactions

May increase toxicity of theophylline, warfarin, and digoxin; effects are reduced with coadministration of aluminum and/or magnesium antacids; nephrotoxicity and neurotoxicity may occur when coadministered with cyclosporine

Contraindications

Documented hypersensitivity; hepatic impairment
Sudden death may occur when azithromycin is taken concurrently with pimozide

Precautions

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

Precautions

Site reactions can occur with IV route; bacterial or fungal overgrowth may result with prolonged antibiotic use; may increase hepatic enzymes and cholestatic jaundice; caution in patients with impaired hepatic function, prolonged QT intervals, or pneumonia; caution in hospitalized, geriatric, or debilitated patients

Trimethoprim, sulfamethoxazole (Septra DS, Bactrim DS)

Inhibits bacterial synthesis of dihydrofolic acid by competing with para-aminobenzoic acid. This results in the inhibition of bacterial growth.
The antibacterial activity of TMP-SMZ includes common urinary tract pathogens, except Pseudomonas aeruginosa.

Dosing

Adult

1 tab PO bid for 10-14 d

Pediatric

<2 months: Do not administer
>2 months: 8 mg/kg TMP and 40 mg/kg SMZ qd

Interactions

May increase PT when used with warfarin (perform coagulation tests and adjust dose accordingly); coadministration with dapsone may increase blood levels of both drugs; coadministration of diuretics increases incidence of thrombocytopenia purpura in elderly persons; phenytoin levels may increase with coadministration; may potentiate effects of methotrexate in bone marrow depression; hypoglycemic response to sulfonylureas may increase with coadministration; may increase levels of zidovudine

Contraindications

Documented hypersensitivity; megaloblastic anemia due to folate deficiency

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Discontinue at first appearance of skin rash or sign of adverse reaction; obtain CBCs frequently; discontinue therapy if significant hematologic changes occur; goiter, diuresis, and hypoglycemia may occur with sulfonamides; prolonged IV infusions or high doses may cause bone marrow depression (if signs occur, give 5-15 mg/d leucovorin); caution in folate deficiency (eg, chronic alcoholics, elderly persons, those receiving anticonvulsant therapy, or those with malabsorption syndrome); hemolysis may occur in G-6-PD deficient individuals; AIDS patients may not tolerate or respond to TMP-SMZ; caution in renal or hepatic impairment (perform urinalyses and renal function tests during therapy); give fluids to prevent crystalluria and stone formation

Ciprofloxacin (Cipro)

An alternative to Septra DS; a bactericidal antibiotic that inhibits bacterial DNA synthesis, and, consequently, growth, by inhibiting DNA-gyrase in susceptible organisms.
Indicated for pseudomonal infections and those that are due to multi-drug-resistant gram-negative organisms. Duration of treatment depends upon severity of infection. Generally, continue therapy for at least 2 d after the signs and symptoms of infection have disappeared. Usual treatment duration is 7-14 d.

Dosing

Adult

500 mg PO bid for 10-14 d

Pediatric

Not established

Interactions

Antacids, iron salts, and zinc salts may reduce serum levels; administer antacids 2-4 h before or after taking fluoroquinolones; cimetidine may interfere with metabolism of fluoroquinolones; ciprofloxacin reduces therapeutic effects of phenytoin; probenecid may increase ciprofloxacin serum concentrations
May increase toxicity of theophylline, caffeine, cyclosporine, and digoxin (monitor digoxin levels); may increase effects of anticoagulants (monitor PT)

Contraindications

Documented hypersensitivity

Precautions

Pregnancy

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

In prolonged therapy, perform periodic evaluations of organ system functions (eg, renal, hepatic, hematopoietic); adjust dose in renal function impairment; superinfections may occur with prolonged or repeated antibiotic therapy

Follow-up

Further Inpatient Care

• Most cases of epididymitis can be managed on an outpatient basis. However, admit the patient for parenteral therapy if any of the following are present:
  • Intractable pain
  • Nausea or vomiting that interferes with oral therapy
  • Clinical evidence of an abscess or when an abscess cannot be ruled out
  • Signs of toxicity or possible sepsis
  • Failure to improve during initial 72 hours of outpatient management
  • Immunocompromised patient with significant signs or symptoms

Further Outpatient Care

• Initiate treatment as discussed above.
• The patient must be evaluated by a urologist within 3-7 days of presentation. This follow-up is mandatory, as a testicular tumor occasionally is the true cause of the symptoms.⁷
• The patient must receive detailed instructions for treatment, including reasons for immediate return.
• Patients with epididymitis secondary to a potential sexually transmitted disease and all of their sexual contacts need referrals in order to screen and diagnose all comorbid STDs, to include HIV.
• In pediatric patients with no prior urological history and in the absence of bacteriuria, one retrospective study suggests that investigation for underlying urinary tract pathology should be carried out after the second episode.⁵

Deterrence/Prevention

• When treating epididymitis secondary to C trachomatis or N gonorrhoeae, treatment of all sexual partners is necessary in order to limit the rate of recurrence and to achieve maximal cure rates.
• Reinforce the advisability of condom use in the prevention of disease.

Complications

Complications of epididymitis may include the following:

• Infertility
• Scrotal abscess formation
• Epididymo-orchitis
• Sepsis
• Fournier gangrene (necrotizing synergistic infection)

Prognosis

• Pain improves within 1-3 days, but induration may take several weeks or months to resolve.
• Sterility may result from bilateral involvement.

Patient Education

• The patient should limit activity.
• The scrotum should be immobilized.
• Stress that the course of antibiotics needs to be completed.
• Stress the need for screening tests and treatment of comorbid sexually transmitted diseases for both the patient and his sexual partners
• For excellent patient education resources, visit eMedicine's Men's Health Center, Bacterial and Viral Infections Center, and Sexually Transmitted Diseases Center. Also, see eMedicine's patient education articles Testicle Infection (Epididymitis), Inflammation of the Testicle (Orchitis), Mumps, and Sexually Transmitted Diseases.

Miscellaneous

Medicolegal Pitfalls

• One must have a high index of suspicion for testicular torsion when evaluating patients with acute testicular or scrotal pain.
• The most common misdiagnosis for testicular torsion is epididymitis. Often, this results from reliance on imperfect diagnostic tests over clinical judgment. Surgical exploration to definitively exclude torsion is not a high-risk procedure. Insist on rapid, in person, consultation by the urologist in suspect cases.
• Admit patients with signs of significant systemic toxicity to the hospital for parenteral therapy.
• All patients discharged with a diagnosis of epididymitis require follow-up in order to be certain a testicular tumor is not the cause of the symptoms.
• Evaluation or referral regarding syphilis and HIV infection often is neglected in cases with a sexually transmitted cause.

References

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Keywords

epididymitis, epididymo-orchitis, intrascrotal inflammation, Escherichia coli, Chlamydia trachomatis, Neisseria gonorrhoeae, chemical epididymitis, epididymal abscess, testicular abscess, sterility, peritubular fibrosis, sexually transmitted epididymitis, urethritis, scrotal pain, scrotal edema, urinary frequency, urinary urgency, dysuria, urinary retention, urethral discharge, scrotal abscess, Prehn sign, candidal epididymitis

Contributor Information and Disclosures

Author

Catherine Tubridy, MD, Staff Physician, Combined Residency Program for Emergency Medicine and Internal Medicine, State University of New York Downstate/Kings County Hospital Centers
Catherine Tubridy, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Emergency Medicine, and Medical Society of the State of New York
Disclosure: Nothing to disclose.

Coauthor(s)

Richard Sinert, DO, Associate Professor of Emergency Medicine, Clinical Assistant Professor of Medicine, Research Director, State University of New York College of Medicine; Consulting Staff, Department of Emergency Medicine, Kings County Hospital Center
Richard Sinert, DO is a member of the following medical societies: American College of Physicians and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Medical Editor

Robert M McNamara, MD, FAAEM, Chair and Professor, Department of Emergency Medicine, Temple University School of Medicine
Robert M McNamara, MD, FAAEM is a member of the following medical societies: American Academy of Emergency Medicine, American Medical Association, Pennsylvania Medical Society, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: Nothing to disclose.

Managing Editor

Richard Sinert, DO, Associate Professor of Emergency Medicine, Clinical Assistant Professor of Medicine, Research Director, State University of New York College of Medicine; Consulting Staff, Department of Emergency Medicine, Kings County Hospital Center
Richard Sinert, DO is a member of the following medical societies: American College of Physicians and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

CME Editor

John D Halamka, MD, MS, Associate Professor of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center; Chief Information Officer, CareGroup Healthcare System and Harvard Medical School; Attending Physician, Division of Emergency Medicine, Beth Israel Deaconess Medical Center
John D Halamka, MD, MS is a member of the following medical societies: American College of Emergency Physicians, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Chief Editor

Barry E Brenner, MD, PhD, FACEP, Program Director, Professor, Department of Emergency Medicine, Professor, Internal Medicine, University Hospitals, Case Western Reserve School of Medicine
Barry E Brenner, MD, PhD, FACEP is a member of the following medical societies: Alpha Omega Alpha, American Academy of Emergency Medicine, American College of Chest Physicians, American College of Emergency Physicians, American College of Physicians, American Heart Association, American Thoracic Society, Arkansas Medical Society, New York Academy of Medicine, New York Academy of Sciences, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

The authors and editors of eMedicine gratefully acknowledge the contributions of previous author, Michael B Brooks, MD, to the development and writing of this article.

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