In places where<unk>  is widespread, diagnosis can be made based on development of parotitis and history of exposure to someone with<unk> . In places where<unk>  is less common, because parotitis has other causes, laboratory diagnosis may be needed to verify<unk>  infection. A differential diagnosis may be used to compare symptoms to other diseases, including allergic reaction, mastoiditis, measles, and pediatric HIV infection and rubella. MuV can be isolated from saliva, blood, the nasopharynx, salivary ducts, and seminal fluid within one week of the onset of symptoms, as well as from cell cultures. In meningitis cases, MuV can be isolated from CSF. In CNS cases, a lumbar puncture may be used to rule out other potential causes, which shows normal opening pressure, more than ten leukocytes per cubic millimeter, elevated lymphocyte count in CSF, polymorphonuclear leukocytes up to 25% of the time, often a mildly elevated protein level, and a slightly reduced glucose ratio up to 30% of the time.<unk> -specific IgM antibodies in serum or oral fluid specimens can be used to identify<unk> . IgM quantities peak up to eight days after the onset of symptoms, and IgM can be measured by enzyme-linked immunosorbent assays (ELISA) 7–10 days after the onset of symptoms. Sensitivity to IgM testing is variable, ranging from as low as 24–51% to 75% in the first week and 100% thereafter. Throughout infection, IgM titres increase four-fold between the acute phase and recovery. False negatives can occur in people previously infected or vaccinated, in which case a rise is serum IgG may be more useful for diagnosis. False positives can occur after infection of parainfluenza viruses1 and 3 and Newcastle disease virus as well as recently after<unk>  vaccination. Antibody titers can also be measured with complement fixation tests, hemagglutination assays, and neutralization tests. In vaccinated people, antibody-based diagnosis can be difficult since IgM often times cannot be detected in acute phase serum samples. In these instances, it is easier to identify MuV RNA from oral fluid, a throat swab, or urine. In meningitis cases, MuV-specific IgM can be found in CSF in half of cases, and IgG in a 30–90%, sometimes lasting for more than a year with increased white blood cell count. These findings are not associated with increased risk of long-term complications. Most parotitis cases have elevated white blood cell count in CSF. Real-time reverse transcription polymerase chain reaction (rRT-PCR) can be used to detect MuV RNA from the first day symptoms appear, declining over the next 8–10 days. rRT-PCR of saliva is typically positive from 2–3 days before parotitis develops to 4–5 days after and has a sensitivity of about 70%. Since MuV replicates in kidneys, viral culture and RNA detection in urine can be used for diagnosis up to two weeks after symptoms begin, though rRT-PCR used to identify the virus in urine has a very low sensitivity compared to virus cultures at below 30%. In meningoencephalitis cases, a nested RT-PCR is able to detect MuV RNA in CSF up to two years after infection. In sialadenitis cases, imaging shows enlargement of the salivary glands, fat stranding, and thickening of the superficial cervical fascia and platysma muscles, which are situated on the front side of the neck. If parotitis occurs only on one side, then detection of<unk> -specific IgM antibodies, IgG titer, or PCR is required for diagnosis. In cases of pancreatitis, there may be elevated levels of lipase or amylase, an enzyme found in saliva and the pancreas.<unk>  orchitis is usually diagnosed by white blood cell count, with normal differential white blood cell counts. A complete blood count can show above or below average white blood cell count and an elevated C-reactive protein level. Urine analysis can exclude bacterial infections. If orchitis is present with normal urine analysis, negative urethral cultures, and negative midstream urine, then that can indicate<unk>  orchitis. Ultrasounds typically show diffuse hyper-vascularity, increased volume of the testes and epididymis, lower than usual ability to return ultrasound signals, swelling of the epididymis, and formation of hydroceles. Echo color doppler ultrasound is more effective at detecting orchitis than ultrasound alone.
Mumps
Chickenpox
Smallpox
Larva currens
Cowpox
Sealpox
Scabies
Malaise