Parainfluenza Virus 1, 2, 3
Parainfluenza Virus 1, 2, 3
Clinical Background
Parainfluenza viruses (PIV) are the second most common cause of acute upper and lower respiratory tract infections (URI and LRTI) in the U.S. for children younger than 5 years.
Epidemiology
- Prevalence
- PIV causes 65% of croup cases, 20-40% of LRTIs and 20% of URIs in preschool children
- 3/1000 cases of croup require medical attention per year
- Age – usually in children 3-5 years
- Transmission – via respiratory droplet
Classification
- PIV types 1, 2, and 3 are clinically the most common
- Types 1 and 2 are the primary causes of laryngotracheobronchitis (croup)
- Seasonal biennial outbreaks in the U.S., currently occurring in the fall of odd-numbered years
- Types 1 and 3 are common in early childhood, causing localized outbreaks in nurseries, schools, orphanages, and pediatric wards
- Type 3 is second only to respiratory syncytial virus (RSV) as a cause of bronchiolitis and pneumonia in infants
- Can cause parotiditis similar to mumps
- Peak is late spring
- PIV type 4 is less well-studied but also causes URI and LRTI
Organism
- An enveloped and single-stranded RNA virus belonging to the Paramyxoviridae family
- Other viruses in this family include RSV, mumps, measles, metapneumovirus (hMPV), Hendra and Nipah viruses
Clinical Presentation
- May present as mild upper respiratory illness, croup, bronchiolitis or pneumonia
- Older children and adults tend to have milder disease
Treatment
- Treatment is symptomatic and supportive.
Diagnosis
Indications for Testing
- Flu-like illness during PIV season
Laboratory Testing
- Clinical diagnosis usually suffices
- Sequential panel antibody testing
- Supports the diagnosis
- Cross reactivity can occur with assays for IgG, particularly due to the mumps virus
- Usually not necessary, except possibly during epidemic events
- Viral culture – gold standard
- Conventional culture requires up to 7 days
- Rapid culture requires less time (24-48 hours)
- Direct fluorescent antibody (DFA) stain is most rapid diagnostic test
- Also includes testing for influenza, adenovirus, RSV, and hMPV
- Less sensitive than culture, PCR.
- Polymerase chain reaction (PCR) – most sensitive, some assays can detect parainfluenza 4
Differential Diagnosis
- Adenovirus
- Bordetella pertussis
- Chlamydia pneumoniae
- Enterovirus
- Influenza
- Metapneumovirus
- Mycoplasma pneumoniae
- Respiratory syncytial virus
Indications for Laboratory Testing
- Tests generally appear in the order most useful for common clinical situations
- Click on number for test-specific information in the ARUP Laboratory Test Directory
| Test Name and Number |
Recommended Use |
Limitations |
Follow Up |
| Respiratory Viruses DFA with Reflex to Viral Culture 0060281 Method: Direct Fluorescent Antibody Stain |
Confirm presence of viral infection |
Sensitivity of DFA methodology is dependent on the adequacy of the specimen |
|
| Parainfluenza Virus Antibodies (1, 2, 3), IgG & IgM 0051084 Method: Enzyme-Linked Immunosorbent Assay |
Parainfluenza virus antibody testing might be indicated if, during flu season, a rapid influenza test result is negative
Note: Panel test is recommended over the individual virus tests since cross-reactivity can occur
|
|
|
| Viral Culture 0065008 Method: Cell Culture |
Historically the gold standard test for identifying parainfluenza virus
|
|
|
| Respiratory Viruses Rapid Culture 2001504 Method: Cell Culture/Immunofluorescence |
Respiratory viruses that can be isolated include influenza A & B, adenovirus, RSV, and parainfluenza types 1,2,3 |
Other viruses such as HSV or CMV will not be routinely detected in this culture Test has decreased sensitivity for detection of adenovirus |
|
Additional Tests Available
Click the plus sign to expand the table of additional tests.
| Test Name and Number | Comments |
| Parainfluenza Virus 1 Antibody, IgM 0051070 Method: Enzyme-Linked Immunosorbent Assay |
|
| Parainfluenza Virus 2 Antibody, IgG 0051071 Method: Enzyme-Linked Immunosorbent Assay |
|
| Parainfluenza Virus 2 Antibody, IgM 0051072 Method: Enzyme-Linked Immunosorbent Assay |
|
| Parainfluenza Virus 3 Antibody, IgG 0051082 Method: Enzyme-Linked Immunosorbent Assay |
|
| Parainfluenza Virus 3 Antibody, IgM 0051083 Method: Enzyme-Linked Immunosorbent Assay |
|
| Parainfluenza Virus 1 Antibody, IgG 0051068 Method: Enzyme-Linked Immunosorbent Assay |
|
| Respiratory Viruses DFA 0060289 Method: Direct Fluorescent Antibody Stain |
|
| Viral Culture 0065008 Method: Cell Culture |
|
Comprehensive Review: September 2009
Last Update: August 2009