Epididymitis and orchitis
How bacteria travel backwards down the ductus deferens to inflame the epididymis, how mumps damages the seminiferous tubules inside a rigid capsule, how tuberculosis and syphilis form granulomas, and how to tell infection from a twisted testis.
By the end, you can
- Describe the testis, epididymis and ductus deferens, the tunica albuginea and the blood–testis barrier.
- Explain how the usual organisms of epididymitis differ with age and sexual exposure, and why infection starts in the tail of the epididymis.
- Explain how mumps orchitis damages the seminiferous tubules, and why atrophy and reduced fertility can follow.
- Compare tuberculous, syphilitic and idiopathic granulomatous orchitis, and relate abscess, infarction and duct obstruction to their causes.
- Distinguish epididymo-orchitis from testicular torsion, recognise the classic tissue changes and tests, and explain how the main treatments act on each mechanism.
What it is
Epididymitis is inflammation of the epididymis, usually from bacteria that travel backwards from the urethra or the urinary tract; when the testis is inflamed too it is epididymo-orchitis. Orchitis confined to the testis is usually viral, most often mumps. Granulomatous forms follow tuberculosis, syphilis or an immune reaction of unknown cause. Acute epididymitis lasts under six weeks; chronic epididymitis, six weeks or more.
4 types to tell apart
- Acute bacterial epididymitis and epididymo-orchitis
- Sexually transmitted organisms (Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium) in younger, sexually active men; E. coli and other urinary bacteria in older men, after instrumentation and after insertive anal sex.
- Viral orchitis
- Mostly mumps, reaching the testis through the blood a few days after the parotid glands swell; other viruses are rarer.
- Granulomatous epididymitis and orchitis
- Tuberculosis (epididymis first), syphilis (testis first), idiopathic granulomatous orchitis, brucellosis, fungi and sperm granulomas.
- Non-infective epididymitis
- Sterile urine pushed down the ducts by straining, trauma, the heart drug amiodarone and Behçet disease.
Normal function
From tubule to duct: the testis and epididymis
Each hangs in the scrotum inside a tough, inelastic fibrous capsule, the tunica albuginea, which sends partitions inwards to divide it into lobules of coiled seminiferous tubules. A serous sac, the tunica vaginalis, covers its front and sides, so the testis can glide; normally it is anchored to the back of the scrotum, which stops it twisting. Between the tubules, Leydig cells make testosterone.
Sertoli cells line the tubules and are joined by tight junctions into the blood–testis barrier. Germ cells that mature after puberty carry new surface proteins the immune system has never met; the barrier keeps them hidden, which matters when inflammation breaks it.
Sperm leave through the rete testis and efferent ductules into the of the epididymis, a single duct coiled into a comma along the back of the testis, about 6 m long if uncoiled. They mature as they pass along its to its , where the duct straightens into the . The ductus runs up the spermatic cord with the and the , through the inguinal canal into the pelvis, and joins the duct of the seminal gland to form an ejaculatory duct, which opens into the prostatic urethra.
Underlying change · Step 1 of 6
Epididymitis: infection that travels backwards
The full lesson is part of Student Pro
It takes you through all 6 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Disrupted function · Step 2 of 6
The inflamed epididymis and testis
The full lesson is part of Student Pro
It takes you through all 6 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Disrupted function · Step 3 of 6
Viral orchitis: mumps inside a rigid capsule
The full lesson is part of Student Pro
It takes you through all 6 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Disrupted function · Step 4 of 6
Granulomatous forms: tuberculosis, syphilis and the idiopathic kind
The full lesson is part of Student Pro
It takes you through all 6 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Consequences · Step 5 of 6
Atrophy and reduced fertility
The full lesson is part of Student Pro
It takes you through all 6 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Consequences · Step 6 of 6
The emergency it must not be: testicular torsion
The full lesson is part of Student Pro
It takes you through all 6 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Symptoms and signs
Symptoms, signs and findings
The full lesson is part of Student Pro
It takes you through all 6 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Exam detail
Exam detail
The full lesson is part of Student Pro
It takes you through all 6 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Treatment
How treatment works
The full lesson is part of Student Pro
It takes you through all 6 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Recap
Recap
The full lesson is part of Student Pro
It takes you through all 6 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Self-check
Check your understanding
The full lesson is part of Student Pro
It takes you through all 6 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .