Clinical presentation of mumps

Pathogenesis and viral dissemination

The entry portal for the mumps virus is the mucous membrane of the oro- and nasopharynx. The pathogenesis of the disease includes several successive stages:

1. Primary replication. The virus multiplies in the epithelial and lymphoid cells of the entry portal.
2. Lymphogenic spread. The pathogen penetrates into regional lymph nodes, where the formation of an immune response is triggered.
3. Primary viremia. Even during the incubation period, the virus breaks into the bloodstream.
4. Hematogenous dissemination. With the blood flow, the pathogen is carried to target organs: salivary glands, testes, pancreas, meninges.
5. Secondary replication. Massive reproduction of the virus in glandular tissues against the background of the forming immunity.

It is immuno-mediated cytolysis of infected cells that is accompanied by the release of pro-inflammatory cytokines. This leads to the development of intoxication syndrome and characteristic morphological changes: pronounced interstitial edema and lymphohistiocytic infiltration.

Important postulate: the localization of inflammation outside the salivary glands is not a complication, but a manifestation of the systemic underlying process.

Typical presentation: salivary gland involvement

The disease manifests with a prodromal period (up to 24–48 hours), during which weakness, myalgia, headache, and chills are noted.

The acute period lasts 7–9 days. It begins with a sharp rise in temperature up to 39–40°C and signs of interstitial parotitis.

Local symptoms in case of parotid gland involvement:

• Filatov's sign. Tenderness upon palpation behind the earlobe is the earliest sign.
• Nature of swelling. The edema has a doughy consistency, filling the depression between the angle of the mandible and the mastoid process. The skin over the gland is tense and shiny, but skin hyperemia is not characteristic.
• Trismus. It is painful for the patient to chew and open the mouth.
• Mourson's sign. Edema and redness of the opening of the parotid gland excretory duct (ductus parotideus) on the buccal mucosa.
• Hyposalivation. Reduced saliva production leads to dry mouth.

The process often starts on one side, but in 80–90% of cases, the second parotid gland becomes involved within 1–2 days. The submandibular (glandula submandibularis) and sublingual (glandula sublingualis) glands may also be affected.

Combined lesions of other organs

A few days after the onset of the disease, the virus can attack other glandular organs and the CNS. Severe forms of infection always proceed with combined involvement.

Acute pancreatitis Develops on days 4–7. It manifests as pain in the mesogastrium, nausea, and vomiting. Sometimes it is asymptomatic. Diagnosis is complicated by the fact that the usual marker (hyperamylasemia) in mumps rises due to the damage to the salivary glands themselves.

Orchitis and oophoritis Orchitis occurs in 30–50% of male patients in the postpubertal period. It manifests as a second wave of fever, severe pain in the scrotum, and testicular enlargement. In women (about 5% of cases), the development of oophoritis is possible, which can mimic the picture of acute appendicitis.

Nervous system involvement Most often proceeds in the form of serous meningitis. Severe headache, repeated vomiting, and moderately expressed meningeal signs are characteristic. In the cerebrospinal fluid (CSF), lymphocytic pleocytosis, increased protein, and a specific sign — decreased glucose level — are detected.

Atypical forms and outcomes

There is no single classification of mumps due to the huge polymorphism of manifestations. About 40–50% of all cases occur in an atypical form:

• Without salivary gland involvement (the virus hits only the nervous system or internal organs).
• Under the mask of a common ARVI.
• Subclinically (20–30% of patients have no symptoms at all, but actively shed the virus into the environment).

The convalescence period takes 10–14 days. As a rule, complete recovery occurs. In rare cases, residual pathology forms: diabetes mellitus (due to atrophy of the pancreatic islets), testicular atrophy, or persistent neurological disorders (deafness, paresis).

Briefly: answers to topical questions

Class and exam questions

What else to study on this topic

• Resistance of the mumps virus in the external environment and transmission mechanisms
• Infection epidemiology: prevaccination era vs modern times
• Features of immunity in infants of the first year of life (maternal antibodies)
• Pathomorphological changes in glandular tissues (interstitial parotitis)
• Rare forms of involvement: thyroiditis, mastitis, and meningoencephalitis

Other topics in the "Respiratory Infections" section

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