mumps
Introduction
Introduction to mumps Epidemic parotitis (mumps, mumps or salivation) is a common respiratory infection in children and adolescents. It is also caused by adult mumps virus. The non-suppurative swelling of the parotid gland is a prominent symptom, and the virus can invade various glandular tissues or nervous systems and almost all organs such as liver, kidney, heart, and joints. Therefore, it can often cause meningoencephalitis, orchitis, pancreatitis, mastitis, ovarian inflammation and other symptoms. basic knowledge The proportion of patients: The number of patients in this patient is about 5% in a specific population. Susceptible people: children Mode of infection: droplet spread Complications: polio, polyneuritis, deafness, orchitis, oophoritis, pancreatitis, nephritis, myocarditis
Cause
Cause of mumps
Source of infection (30%):
Early patients and latent infections. The virus is present in the patient's saliva for a longer period of time. The virus is isolated from the patient's saliva from 6 days before the onset of swelling to 9 days after the onset of the carbuncle, and is therefore highly contagious within the two weeks. After mumps virus infection, there is no mumps, and other organs such as brain or testicular symptoms, saliva and urine can also detect the virus. About 30-40% of patients in the pandemic have only subclinical infections of upper respiratory tract infection, which is an important source of infection.
Route of transmission (30%):
The virus spreads through saliva in saliva (saliva and contaminated clothing can also be transmitted), its infectivity is weaker than measles and chickenpox. Pregnant women infected with this disease can pass the placenta to the fetus, causing fetal malformation or death, and the incidence of miscarriage is also increased.
Susceptibility (25%):
It is generally susceptible and its susceptibility decreases with age. More men than women after puberty. May have long-lasting immunity after illness.
Etiology
The mumps virus (paramyxovirus parotitis) and the parainfluenza new city, measles, respiratory syncytial virus and other viruses belong to the paramyxovirus-type ribonucleic acid (RNA) type, which was isolated from the patient's saliva in 1934 and successfully infected monkeys and "volunteers". ". The virus has a diameter of about 85 to 300 nm and an average of 140 nm. It is sensitive to the effects of physical and chemical factors. 1% of sulphate, ethanol, 0.2% fumarin can be inactivated within 2 to 5 minutes; it is rapidly killed by exposure to ultraviolet light; the virus is cold-tolerant and has a low temperature resistance. It can live for more than 1 year at -50 to -70 °C. It can be stored for 2 months at 4 °C, 24 hours at 37 °C, and 20 minutes at 55-60 °C. The virus is found only in humans but can be propagated in tissue culture of monkeys, chicken embryonic amniotic membranes and various human and monkeys. Monkeys are most susceptible to this disease. The virus has only one serotype.
The nucleocapsid protein of mumps virus has a soluble antigen (S antigen) whose outer surface contains neuraminidase and a hemagglutininglycoprotein has a viral antigen (V antigen). The S antigen and the V antigen each have their corresponding antibodies. The S antibody appeared on the 7th day after onset and peaked within two weeks, and then gradually decreased. It can be maintained for 6 to 12 months by the complement binding method. The S antibody is not protective. V antibody can be measured at 2 to 3 weeks after onset, and peaks after 1 to 2 weeks, but there is a long-term use of complement binding, hemagglutination resistance and neutralizing antibody detection, which is the best indicator for detecting immune response. It has a protective effect. Infection with mumps virus can produce an immune response regardless of whether it is ill or not, and re-infection is rare. Mumps virus can be isolated from saliva, blood, cerebrospinal fluid or thyroid in the early stages of the disease. The virus rarely mutates, and the antigenicity between the strains is very close.
Pathogenesis
It is believed that the virus first invades the oral mucosa and the nasal mucosa and proliferates in the epithelial tissue and enters the blood circulation (first viremia). The blood flow involves the parotid gland and some tissues, and then proliferates again into the blood circulation (second virus) Hemorrhage) and infringe on some organs that were not affected by the last time. Mumps virus can be isolated from the mouth, respiratory secretions, hematuria, milk, cerebrospinal fluid and other tissues in the early stages of the disease. Some people isolated the virus from the human placenta and the fetus. According to the fact that patients with this disease can always have no swelling of the parotid gland and meningoencephalitis and orchitis can occur before the swelling of the parotid gland, it also proves that the mumps virus first invades the oral and nasal mucosa and affects various organ tissues through blood flow. Some people think that the virus has a special affinity for the parotid gland. Therefore, after entering the cavity, the parotid gland is invaded into the parotid gland. After proliferating in the gland, it enters the blood circulation to form viremia and affects other tissues. Various glandular tissues such as testis ovary, pancreas, intestinal effusion, thymus gland, thyroid gland, etc. have been invaded, brain meninges, liver and myocardium are often involved, so the clinical manifestations of mumps vary with cerebral encephalitis It is a consequence of the direct invasion of the central nervous system by the virus, and pathogens may be isolated from the cerebrospinal fluid.
Non-suppurative inflammation of the parotid gland The main pathological glands of the disease are swollen and red, with exudates, hemorrhagic lesions and leukocyte infiltration, parotid ducts with catarrhal inflammation, and serous fibers around the duct and gland. Protein exudation and lymphocytic infiltration, tube filling and broken cell residual and a small amount of neutrophil glandular epithelial edema, necrosis, acinar blood vessels are congested. The spleen is markedly edema, and the nearby lymph nodes are hyperemic and swollen. There was not much change in saliva composition, but the amount of secretion was less than normal.
Because the partial obstruction of the parotid duct obstructs the discharge of saliva, it can be caused by increased salivation and saliva retention when eating an acidic diet. Saliva contains amylase which can enter the blood circulation through the lymphatic system, resulting in an increase in blood amylase. The enzyme content of the pancreas and intestinal pulp is excreted from the urine. The disease virus is easy to invade the mature testis. The younger patients rarely develop orchitis. The epithelium of the testicular vas deferens is significantly congested, with bleeding spots and lymphocytic infiltration, edema and serous fibrinous exudate in the interstitial. , edema, mild degeneration of the islets and fatty necrosis.
Prevention
Mumps prevention
The patient should be isolated early until the parotid gland completely subsides. The contact is generally not necessarily quarantined. However, in the group of children's institutions (including hospitals, schools), the troops should be kept for 3 weeks, and suspicious patients should be temporarily isolated.
Live mumps attenuated live vaccine: Live attenuated vaccine for chicken embryo cell culture, which has been widely used abroad since 1966. Its anti-infective effect can reach 97% in children and 93% in adults. Mumps live vaccine and measles The rubella vaccine was used in combination at the same time, and the results were satisfactory. The three did not interfere with each other. After immunization, the malignant antibody of mumps virus can be maintained for at least 9.5 years.
In addition to intradermal injection and subcutaneous injection, the immunization route of live mumps live vaccine can also be performed by nasal spray or aerosol inhalation (in the aerosol chamber).
China's materials prove that after half a year of immunization (in total of nasal spray and aerosol inhalation), the incidence rate of children's immunization group (7.4%) is significantly lower than that of the corresponding control group (78.5%), and the incidence rate of adult immunization group (0.33%) is also lower. The corresponding control group (4.6%) had no adverse reactions. The incidence of mumps vaccine (including adults) should be arranged in a planned manner for the incidence of this disease in China, especially for kindergartens. Universal immunization can significantly reduce the incidence of disease, and China has begun to gradually promote the application of the vaccine.
Live mumps live vaccines should not be used in pregnant women (to prevent adverse effects of viral infection through the placenta), and those who are congenitally or acquired immunocompromised and who are allergic to egg proteins (because live vaccines are obtained from chicken embryos).
Generally, immunoglobulin, adult blood or placental globulin does not prevent the disease. The blood of the recovery period and its immunoglobulin or specific high-priced immunoglobulin may be useful, but the source is difficult, difficult to obtain, and protected after use. The time is short, only 2 to 3 weeks, so it is not used much, and its effect needs further study.
Complication
Mumps complications Complications polio polyneuritis deafness orchitis ovarian pancreatitis nephritis myocarditis
Mumps is actually a systemic infection, and the virus often involves the central nervous system or other glands or organs to produce the corresponding symptoms. Even some complications are not only common but can occur alone without the enlargement of the parotid gland.
First, the nervous system complications
1. Aseptic meningitis, meningoencephalitis, encephalitis : common complications, meningoencephalitis accounted for 94.08% of various complications reported by epidemic mumps in Shanghai Medical University Pediatric Hospital. Especially occurs in children with more boys than girls. The incidence of encephalitis in mumps is about 0.3% to 8.2%. Since it is not possible to perform cerebrospinal fluid examination in all patients with mumps, and in some cases, no parotid swelling has been observed, so it is difficult to calculate the exact incidence. The symptoms of meningoencephalitis can occur as early as 6 days before or after 2 weeks of swelling of the parotid gland, and usually appear within 1 week after the swelling. Acute brain edema such as headache and vomiting is more obvious. EEG can be changed but not similar to other viral encephalitis. Mainly due to meningeal involvement, the prognosis is good, and individual encephalitis cases can also lead to death. 25% to 50% can be free of parotid swelling. There are serologically confirmed cases of mumps encephalitis in China, and there is no swelling of the parotid gland from beginning to end.
Encephalitis: The clinical features are sudden high fever, disturbance of consciousness, headache, strong neck, upper limbs and neck and scapular tendon, and sequelae are more common.
2, polyneuritis, poliomyelitis, etc .: occasional mumps 1 to 3 weeks after the emergence of multiple neuritis, polio, the prognosis is good. A swollen parotid gland may compress the facial nerve to cause temporary facial paralysis. Sometimes there are balance disorders, trigeminal neuritis, hemiplegia, paraplegia, ascending paralysis. Occasionally, due to stenosis of the aqueduct after mumps, complicated with hydrocephalus.
Polyneuritis: polyneuritis, formerly known as peripheral neuritis, refers to the symmetry damage of most peripheral nerves caused by various causes, mainly characterized by symmetry of the distal limbs, motor and autonomic disorders. Lower motor neuron spasms and diseases of autonomic dysfunction.
Polio: poliomyelitis (hereinafter referred to as polio), also known as polio, is an acute infectious disease caused by poliovirus. Clinical manifestations include fever, sore throat, and limb pain, and some patients may experience flaccid paralysis. In the epidemic, there are many cases of occult infection and innocent sputum. The incidence of children is higher than that of adults. Before the vaccination, especially infants and young children are sick, so it is also called polio. The main lesion is in the gray matter of the spinal cord, and severe lesions may have sequelae of sputum.
3, deafness : caused by the involvement of the auditory nerve. Although the incidence is not high (about 1/15000), it can be permanent and complete deafness. Fortunately, 75% of deafness occurs only in one side of the ear.
Deafness: According to the WHO 1980 deafness classification standard, the average speech frequency pure tone hearing threshold is divided into 5 levels. Mild sputum: There is no difficulty in listening to general conversation at close range. The audiometer and audio listening threshold of the audiometer are 26~40dB. Moderate : It is difficult to listen at a close distance, and the hearing threshold is 41 to 55 dB. Moderate and severe sputum: It is difficult to listen to loud language at close range, and the listening threshold is 56~70dB. Severe sputum: You can hear it by shouting in your ear, listening threshold 71~91dB. Full : I can't hear the loud voice shouting in my ear. The pure tone listening and listening threshold is over 91dB.
Second, reproductive system complications Mumps virus is a good invasion of mature gonads, it is more common in patients after the late adolescence, children are rare.
1. Orchitis : The incidence rate accounts for 14% to 35% of male adult patients, but there are reports that 9-year-old children have this disease. Generally, the incidence rate is significantly increased after 13 to 14 years old. Often occurs when the parotid gland enlarges about 1 week and begins to subside. Sudden high fever, chills, testicular pain, severe tenderness, and varying symptoms are usually about 10 days. Scrotal skin edema is significant, and there may be yellow effusion in the sheath cavity. Most of the lesions invade one side, and about 1/3 to 1/2 of the cases have different degrees of testicular atrophy. Because the lesions are often unilateral, even if only bilateral part of the seminiferous tubule is involved, it rarely causes infertility. Epididymitis often occurs in combination.
Common symptoms of orchitis are as follows: acute high fever, chills, testicular pain to the groin, with nausea and vomiting; acute mumps orchitis, more than 3-4 days after the occurrence of mumps, high fever up to 40 °C often with collapse Scrotum swelling, testicular swelling, hydrocele, obvious tenderness, such as mumps can also be found in parotid swelling.
2, ovarian inflammation : about 5% to 7% of adult female patients. The symptoms are mild, do not affect pregnancy, and can cause early amenorrhea. Ovarian inflammation has a lower back pain, lower abdominal pain, menstrual cycle disorders, severe cases can be swollen and swollen ovarian with tenderness. So far, no reports have been made that lead to infertility.
Common symptoms of ovarian inflammation are as follows: (1) Abdominal pain: There are different degrees of pain in the lower abdomen, mostly hidden discomfort, soreness in the lower back and ankle, swelling, and falling feeling, often aggravated by fatigue. Due to pelvic adhesions, there may be bladder, rectal filling pain or pain when emptying, or other bladder rectal irritation symptoms, such as frequent urination, urgency and so on. (B) irregular menstruation: the frequency of menstruation, excessive menstrual flow is the most common, may be the result of pelvic congestion and ovarian dysfunction. Menorrhagia can be caused by uterine fibrosis, uterine insufficiency or adhesion to the uterus due to chronic inflammation. (3) Infertility: The fallopian tube itself is invaded by the disease, forming a blockage and causing infertility, and it is more common to have infertility. (D) dysmenorrhea: due to pelvic congestion caused by blood stasis dysmenorrhea, mostly in the first week before menstruation, there is abdominal pain, the closer to the menstrual period, the more severe, until menstrual cramps. (5) Others: such as increased vaginal discharge, painful intercourse, gastrointestinal disorders, fatigue, labor affected or insufficiency, mental and neurological symptoms and depression.
3, pancreatitis : about 5% of adult patients, rare in children. It often occurs 3 to 4 days to 1 week after swelling of the parotid gland, with the main symptoms of pain and tenderness in the upper abdomen. With vomiting, fever, bloating, diarrhea or constipation, sometimes it can affect the enlarged pancreas. Symptoms of pancreatic inflammation disappeared within 1 week. Blood amylase should not be used as a basis for diagnosis. The serum lipase value exceeded 25.01 mol·s-1/L (1500 U/L) [normal reference value 3.33 to 11.67 mol·s-1/(200-700 U/L)], suggesting that pancreatitis has recently occurred. Lipase usually rises 72 h after onset, so early diagnosis is of little value. In recent years, as children's patients become more and more serious, the complications of pancreatitis have also increased. In the pediatric hospital affiliated to Shanghai Medical University from 1982 to 1991, 1312 children with hooliganism who were hospitalized due to complications, 35 cases with pancreatitis, accounting for the second place, second only to meningoencephalitis.
Common symptoms of pancreatitis are as follows: (1) Abdominal pain: Most of the acute pancreatitis is sudden onset, which is characterized by severe upper abdominal pain and more radiation to the shoulders and back. The patient feels a sense of "banding" in the upper abdomen and lower back. The location of abdominal pain is related to the location of the lesion. For example, the lesion of the head of the pancreas is severe. The abdominal pain is mainly in the right upper abdomen and radiates to the right shoulder. If the lesion is in the tail of the pancreas, the abdominal pain is the upper left abdomen and the left shoulder is radiated. The intensity of pain is consistent with the extent of the lesion. If it is edematous pancreatitis, abdominal pain is more persistent with increased aggravation, abdominal pain can be relieved by acupuncture or injection of antispasmodic drugs; if hemorrhagic pancreatitis, abdominal pain is very severe, often accompanied by shock, The general analgesic method is difficult to relieve pain. (2) nausea and vomiting: appears at the beginning of the onset, which is characterized by the inability to relieve abdominal pain after vomiting. The frequency of vomiting is also consistent with the severity of the lesion. In edematous pancreatitis, not only nausea, but also often vomiting 1 to 3 times; in hemorrhagic pancreatitis, vomiting is severe or persistent retching frequently. (3) systemic symptoms: may have fever, jaundice and so on. The degree of fever is consistent with the severity of the lesion. Edema pancreatitis, may not have fever or only mild fever; hemorrhagic necrotizing pancreatitis may have high fever, if fever does not retreat, there may be complications, such as pancreatic abscess. The occurrence of jaundice may be caused by concurrent biliary tract disease or compression of the common bile duct by the enlarged pancreatic head.
4, nephritis : early cases of the vast majority of urine can be isolated mumps virus, it is believed that the virus can directly damage the kidney, lighter urine has a small amount of protein, severe urine routine and clinical manifestations similar to nephritis, individual cases can be Death occurs in acute kidney failure. But most of the prognosis is good.
Typical symptoms of nephritis are as follows: clinical manifestations of glomerulonephritis such as proteinuria, hematuria (red blood cells with multiple morphological changes), hypertension, edema, and renal insufficiency.
5, myocarditis : about 4% to 5% of patients with myocarditis. More common in the fifth to the tenth day of the disease, can occur with the parotid gland at the same time or recovery period. The performance is pale, heart rate increases or slows down, heart sounds are low and blunt, arrhythmia, temporary heart enlargement, systolic murmur. Electrocardiogram showed sinus arrest, atrioventricular block, ST-segment depression, T-wave low-level or inversion, pre-systolic contraction, etc. In severe cases, it can be fatal. Most of them only had ECG changes (3% to 115%) without obvious clinical symptoms and occasional pericarditis.
The clinical symptoms of myocarditis are as follows: 1 Asymptomatic type: ST changes in the electrocardiogram 1-4 weeks after infection, asymptomatic. 2 arrhythmia type: showing various types of arrhythmia, ventricular premature contraction is most common. 3 heart failure type: symptoms and signs of heart failure. 4 myocardial necrosis: clinical manifestations similar to myocardial infarction. 5 heart enlargement: heart enlargement, systolic murmur in the mitral and tricuspid valve areas. 6 death type: no aura, sudden death.
6, other : mastitis (31% of female patients over 15 years old with this disease), osteomyelitis, hepatitis, pneumonia, prostatitis, vestibular gland inflammation, thyroiditis, thymitis, thrombocytopenia, urticaria, acute follicular Conjunctivitis and the like are rare. The incidence of arthritis is about 0.44%, mainly involving elbows, knees and other large joints, which can last from 2 days to 3 months and can be fully recovered. It usually occurs within 1 to 2 weeks after the parotid gland, and there is also no parotid gland.
Symptom
Epidemic symptoms of parotid gland Common symptoms Parotid gland swelling Submandibular gland swelling Sensation Muscle sore throat soreness Loss of heat and easy to feel nausea Face muscle soreness
The incubation period is 8 to 30 days, with an average of 18 days. Most of the patients have no prodromal symptoms, and the lower part of the ear is the first symptom. In a few cases, there may be transient non-specific discomfort (hours to 2 days), muscle soreness and appetite may occur. Insufficient, burnout, headache, hypothermia, conjunctivitis, pharyngitis and other symptoms, the disease of Chinese hooliganism has increased in the past 10 years, showing a long heat history, increased complications, and the proportion of hospitalized children in outpatients has also increased.
Most of the onset is more urgent, fever, chill, headache, sore throat, poor appetite, nausea, vomiting, body aches, etc. After several hours to 1-2 days, the parotid gland is significantly enlarged, and the fever varies from 38 to 40 °C. Symptoms are also very inconsistent, adult patients are generally more serious, parotid swelling is the most characteristic, one side is first swollen, but also both sides are swollen at the same time; generally with the earlobe as the center, forward, backward, and under development, like a pear It has a tough shape and an unclear edge. When the gland is swollen, it shows pain and hypersensitivity. When chewing and chewing into an acidic diet, the skin is more intense, the surface is hot, but the surface is hot, but not red, light. Tenderness, the cellulite around the parotid gland can also be edematous, up to the ankle and humeral arch, down to the jaw and neck, and the sternocleidomastoid can also be affected (occasionally edema can appear in front of the sternum) , thus deforming the appearance.
Usually one side of the parotid gland is swollen 1 to 4 days (occasionally 1 week later) involving the contralateral side, bilateral swelling is about 75%, the submandibular gland or sublingual gland can also be affected at the same time, the neck is obviously swollen when the submandibular gland is swollen, jaw The elliptical gland can be softened and tender and tender: the sublingual gland can also be involved at the same time. When the sublingual gland is swollen, the tongue and neck are swollen and dysphagia is present.
The parotid gland (located on the buccal mucosa next to the maxillary second molar) often has redness and swelling in the early stage, and salivary secretion is initially increased, followed by retention, but the dry mouth symptoms are generally not significant.
The swelling of the parotid gland mostly reaches the peak in 1 to 3 days, and gradually subsides and returns to normal after 4 to 5 days. The whole course of disease is about 10 to 14 days.
Atypical cases may be caused by swelling of the parotid gland and symptoms of simple orchitis or meningoencephalitis, as well as swelling of the submandibular gland or sublingual gland.
Examine
Examination of mumps
1. Peripheral blood
Most of the white blood cell counts are normal or slightly increased, and lymphocytes are relatively increased. When there are complications, the white blood cell count can be increased, and occasionally leukemia-like reactions.
2, serum and urine amylase determination
90% of patients have a mild to moderate increase in serum amylase and an increase in urinary amylase, which is helpful for diagnosis. The degree of amylase increase is often proportional to the degree of swelling of the parotid gland, but its increase may also be related to pancreatic and intestinal effusion.
3, serological examination
(1) Neutralizing antibody test: a low titer such as 1:2 indicates a current infection. In recent years, the gel hemolysis test has been applied, which is basically consistent with the neutralization test, and the detection of the neutralizing antibody is simple and rapid, but the method needs further improvement.
(2) Complement binding test: It has auxiliary diagnostic value for suspicious cases, and the titer of double serum (early course and 2nd to 3rd week) is increased by more than 4 times, or a serum titer of 1:64 is diagnostic. . S and F antibodies should be assayed simultaneously if conditions permit. An increase in the S antibody indicates a recent infection, and the increase in the V antibody and the increase in the S antibody only indicates that the infection has occurred in the past.
(3) Hemagglutination inhibition test: chicken embryos infected with virus, amniotic fluid and allantoic fluid can agglutinate red blood cells of chickens, and the recovery serum of mumps patients has strong inhibition of agglutination, while early serum inhibition is weak. If the titer of the two determinations differs by more than 4 times, it is positive.
4, virus separation
In early cases, mumps virus can be isolated from saliva, urine, blood, cerebrospinal fluid, and other tissues such as the brain and thyroid. The procedures are more complicated and are currently unconditionally carried out.
5, urine routine examination
When the urinary kidney is involved, there may be proteinuria, red blood cells, etc. in the urine, and even changes in urine like nephritis.
6, ECG check
ECG icon when combined with myocarditis: arrhythmia, T wave low level, ST segment depression.
Diagnosis
Diagnosis and diagnosis of mumps
Diagnostic criteria
1, suspected cases of fever, chills, fatigue, loss of appetite, 1-2 days after unilateral or bilateral non-suppurative parotid swelling or other salivary gland swelling and pain.
2, confirmed cases
(1) Parotid gland swelling or other salivary gland swelling and tenderness, and the pain is more obvious when eating acidic food. The mouth of the parotid gland is red and swollen. The white blood cell count is normal or slightly lower, and the late lymphocytes increase.
(2) There is a close contact with mumps patients 1 to 4 weeks before onset.
diagnosis
According to the prevalence and exposure history, as well as the characteristics of parotid swelling, the diagnosis is not difficult. In case of atypical suspicious cases, the diagnosis can be further confirmed according to the above laboratory examination methods.
Differential diagnosis
1. Suppurative mumps
Often one side, local redness and tenderness is obvious, and there is a sense of fluctuating in the late stage. When squeezed, pus flows out from the parotid gland, and the total number of white blood cells and neutrophils in the blood is significantly increased.
2, neck and pre-auricular lymphadenitis
The swelling is not centered on the earlobe, and is confined to the neck or the anterior region of the ear. It is a nucleus, harder, with clear edges, tenderness, and superficial activity. It can be found that the tissue associated with the lymph nodes in the neck or anterior region is Inflammation, such as angina, ear sores, etc., the total number of white blood cells and neutrophils increased.
3, symptomatic parotid swelling
In diabetes, malnutrition, chronic liver disease, or the application of certain drugs such as iodide, phenylbutazone, isoproterenol, etc. can cause parotid swelling, symmetry, no swelling and pain, soft touch, tissue examination Mainly for steatosis.
4. Mumps caused by other viruses
It is known that type 1.3 parainfluenza virus, influenza A virus, type A Coxsackie virus, herpes simplex virus, lymphatic choroidal meningitis virus, cytomegalovirus can cause parotid swelling and central nervous system symptoms, requiring pathogenic diagnosis .
5, other causes of parotid swelling
Allergic mumps, parotid duct obstruction, have a history of recurrent attacks, and sudden swelling, rapid swelling, simple parotid gland is mostly seen in adolescent males, due to increased functional secretion, compensatory parotid swelling, no other symptoms .
6. Meningoencephalitis caused by other viruses
Mumps meningoencephalitis can occur before the parotid gland enlargement (some have never been swollen from the parotid gland), and it is difficult to distinguish it from those caused by other viruses. It can be confirmed by the above serological examination, virus isolation and epidemiological investigation.
