Question

A 22-year-old man presents with testicular pain and swelling 5 days after an episode of parotid gland enlargement and fever. Ultrasound confirms orchitis. He reports that he was not vaccinated in childhood. Which of the following statements regarding mumps orchitis is true?

• A. Subfertility occurs in 30-80%
• B. Vaccination provides lifelong immunity
• C. Parotitis lasts 3-12 months
• D. Meningitis is unlikely

Hint:

It is critical to remember that clinically significant mumps orchitis is strictly a postpubertal complication and is exceedingly rare in prepubertal boys.
Furthermore, unilateral testicular involvement is far more common than bilateral, which is the primary reason why absolute, total sterility remains a rare outcome despite the very high rates of observed subfertility.

Answer 1

The Correct Option is A

Concept:
An entirely unvaccinated young adult male acutely presents with unilateral or bilateral orchitis following a highly classic, preceding episode of parotitis, a sequence of events which very strongly points to an active infection with the Mumps virus.
The core objective of this question is to accurately identify the single correct epidemiological or clinical statement regarding the long-term complications and characteristics of mumps orchitis from the provided options.
Step-by-step Explanation:

• Mumps is a highly contagious, acute viral infection caused by an RNA virus belonging to the paramyxovirus family, and is predominantly characterized by the painful, non-suppurative swelling of one or both parotid salivary glands.

• Viral orchitis is universally recognized as the most common extra-salivary complication of mumps infection occurring in postpubertal males, manifesting in approximately 30% to 40% of all such cases.

• The condition typically presents with an abrupt and severe onset of localized testicular pain, marked swelling, erythema, and a high-grade fever, occurring roughly 5 to 10 days after the initial onset of the parotid swelling.

• Following an acute episode of mumps orchitis, progressive testicular atrophy is a highly frequent and dreaded consequence, occurring in about 30% to 50% of all affected testicles due to pressure necrosis and viral-induced damage within the rigid tunica albuginea.

• This significant parenchymal atrophy can subsequently lead to varying, irreversible degrees of impaired spermatogenesis.

• As a direct result, documented subfertility (a marked reduction in normal fertility potential) is frequently reported in a significant proportion of these patients, with large epidemiological studies suggesting rates ranging from 30% to as high as 80% (making Option A the correct statement).

• However, it is vital to note that absolute, complete sterility is exceedingly rare, especially since the orchitis is frequently unilateral, leaving the contralateral testis functionally intact.

• Regarding Option B, while the standard two-dose MMR vaccine is highly effective at preventing the disease, vaccine-induced immunity can progressively wane over time, which explains why large mumps outbreaks can still occasionally occur in highly vaccinated populations of young adults; therefore, it does not guarantee absolute, lifelong immunity for every single individual.

• Regarding Option C, uncomplicated mumps parotitis is an acute illness that usually resolves completely within a brief period of 7 to 10 days, not a prolonged duration of 3 to 12 months.

• Regarding Option D, aseptic meningitis is actually a relatively common and well-recognized neurological complication of mumps, occurring in up to 10% of all clinical cases, which makes the statement asserting that it is "unlikely" factually incorrect.
Final Answer:
Significant subfertility is a common and well-documented long-term complication of mumps orchitis, reliably occurring in approximately 30-80% of affected postpubertal males.