What is Mumps?

An acute, generalized paramyxovirus infection typically presenting with unilateral or bilateral parotitis. Description Painful p...

An acute, generalized paramyxovirus infection typically presenting with unilateral or bilateral parotitis.

Description

• Painful parotitis occurs in 95% of symptomatic mumps cases. Epidemics in late winter and spring. Transmission by respiratory secretions.
• Incubation period is 14 to 24 days.
• System(s) affected: hematologic/lymphatic/immunologic, reproductive, skin, exocrine.

Etiology

Mumps virus replicates in glandular epithelium of parotids, pancreas, and testes, leading to interstitial edema and inflammation.

• Interstitial glandular hemorrhage may occur
• Pressure caused by edema of the testes against the tunica albuginea can lead to necrosis and loss of function.

Preventation

• Vaccination
• Postexposure vaccination does not protect from recent exposure.
• Isolate hospitalized patients for 5 days after onset
• Isolate nonimmune individuals for 26 days after last case onset (social quarantine).

Physical Exam

• Painful parotid swelling (unilateral or bilateral) obscures angle of mandible and elevates earlobe
• Meningeal signs in 15%, encephalitis in 0.5%
• Rarely arthritis, orchitis, thyroiditis, mastitis, pancreatitis, oophoritis, myocarditis
• Rare maculopapular, erythematous rash
• Up to 50% of cases may be very mild.
• Redness at opening of Stensen duct but no pus
• Swelling in sternal area; rare, but pathognomonic of mumps

Diagnostic Tests

• Three special tests used to confirm an outbreak—if positive, report to health department
  • IgM titer (positive by day 5 in 100% of nonimmunized patients)
  • Swab of parotid duct or other affected salivary ducts for viral culture
  • Rise in IgG titer samples; test should be ordered if patient previously immunized: 1st sample within 5 days of onset, and 2nd, 2 weeks later.
• Other potential findings: elevated serum amylase; CSF leukocytosis, or leukopenia.
• Testicular ultrasound may help differentiate mumps orchitis from testicular torsion.

Treatment

• No specific antiviral therapy, only supportive care
• Analgesics to relieve pain
• Avoid corticosteroids for mumps orchitis because they can reduce testosterone concentrations and increase testicular atrophy.
• IVIG only successful for certain autoimmune-based sequelae:
  • Postinfectious encephalitis
  • Guillain-Barré syndrome
  • ITP