21-20: Mumps

Clinical Summary

Mumps is a highly contagious viral disease best known as a cause of parotitis. Vaccination has markedly reduced the rate of disease in the developed world, but many resource-limited countries do not include mumps in their vaccine programs. It remains common worldwide; occasional large outbreaks occur even in countries with well-developed vaccine programs. Mumps is most common in children and spread by respiratory droplets, direct contact, or fomites. Subclinical infection is common in younger children. Disease in adolescents and adults is associated with a higher rate of serious complications.

A nonspecific illness with malaise, myalgias, fever, and headache follows an incubation period of about 2 to 3 weeks. Unilateral or bilateral parotid swelling is the hallmark, although orchitis is seen in about one-third of postpubertal males and pancreatitis in about 4% of patients. Diagnosis is usually clinical, particularly in developing countries. A high amylase from a salivary or pancreatic source might be present; viral isolation, PCR, and serology are available for definitive diagnosis.

Management and Disposition

Mumps is a self-limited, usually mild, disease. Treatment is supportive and consists of antipyretics, fluids, and analgesics. Patients with orchitis might benefit from scrotal support. Patients should be advised to stay home from school or work for 5 days after symptom onset.

Pearls

1. Natural infection confers life-long protection, although rare recurrent cases have been reported.

2. Aseptic meningitis with CSF pleocytosis occurs in more than one-half of patients with mumps, although most are minimally symptomatic. Mumps encephalitis also occurs but is extremely rare.

3. Mumps should be considered in the differential diagnosis of aseptic meningitis, even in the absence of parotitis.

4. Mumps is one of the leading causes of acquired deafness in developing countries.

5. Ovarian and breast inflammation are occasionally seen in females, although it is not as common as orchitis among males. Sterility is rarely seen with either condition.