Physical Findings and Complications

A: Mumps usually involves pain, tenderness and swelling in one or both parotid salivary glands. Swelling is first visible in front of the lower part of the ear. Swelling than extends downward and forward as fluid builds up in the skin and soft tissue of the face and neck. Swelling usually peaks in 1-3 days and then subsides during the next week. The swollen tissue pushes the angle of the ear up and out. As swelling worsens, the angle of the jawbone (mandible) below the ear is no longer visible. On palpation, often the jawbone cannot be felt because of swelling of the parotid. One parotid may swell before the other, and in 25% of patients, only one side swells. Other salivary glands (submandibular and sublingual) under the floor of the mouth also may swell but do so less frequently (10%).

From The Merck Manual of Medical Information – Second Home Edition,
p. 667, edited by Mark H. Beers.
Copyright 2003 by Merck & Co., Inc., Whitehouse Station, NJ.

Mumps infection is most often confused with swelling of the lymph nodes of the neck. Lymph node swelling can be differentiated by the well-defined borders of the lymph nodes, their location behind the angle of the jawbone, and lack of the ear protrusion or obscuring of the angle of the jaw, which are characteristics of mumps.

A: In 50% – 60% of cases of clinical mumps, cerebrospinal fluid (CSF) pleocytosis occurs. However, clinical evidence of meningitis or encephalitis appears in < 10% of patients with mumps. Serious sequelae are rare. For example, deafness after mumps occurs in 0.5 to 5.0 per 100,000 cases. Death occurs in < 2% of mumps encephalitis cases.

Orchitis occurs in about 25% of adolescent and adult males with mumps and is rare in prepubescent males. One or both testes may be involved, with lower abdominal pain, fever, and chills and possibly epididymitis. The involved testis and adjacent skin become swollen and red. Orchitis occurs within 1 week of parotitis and usually lasts 4 days. Infertility is rare even when both testes are involved.

Oophoritis occurs in 5% of post pubertal females with mumps and is characterized by pelvic pain and tenderness. Infertility generally does not occur. Mastitis may also occur.

Less common complications of mumps infection include pancreatitis, myocarditis, arthritis, thyroiditis, deafness, and spontaneous abortion.

For more information see pediatric infectious disease texts, for example:

• Cherry JD. Mumps virus. In: Feigin RD, Cherry JD, Demmler GJ, Kaplan SL, eds. Textbook of Pediatric Infectious Diseases. 5th ed. Philadelphia, Penn: Saunders; 2004:2305–2314.
• Gutierrez K. Mumps virus. In: Long SS, Pickering LK, Prober CG, eds. Principles and Practices of Pediatric Infectious Diseases. 2nd ed. Philadelphia, Penn: Churchill Livingstone; 2003:1136–1140.