Keep specimen at 4C
Respiratory specimen of choice is a NASOPHARYNGEAL ASPIRATE. Collect the aspirate in a leukens trap and immediately transport to Clinical Virology Laboratory. Refer to the Nursing Procedure Manual, Section VII, Respiratory Care, 7:14:a for complete instructions on the collection of a nasopharyngeal aspirate using a leukens trap. Nasal washings, tracheal aspirates, and bronchoalveolar lavage specimens may be submitted. Collection of COMBINED THROAT AND NASOPHARYNGEAL SWABS is recommended for patients in which aspirates or washings cannot be readily obtained. For collection of nasopharyngeal swab specimen: 1. Insert swab into one nostril. 2. Press swab tip on the mucosal surface of the mid-inferior portion of the inferior turbinate, and rub the swab tip several times across the mucosal surface to loosen and collect cellular material. 3. Withdrawal the swab; place swab into tube of Viral Transport Medium. For collection of oropharyngeal swab specimen: 1. Ask patient to open mouth widely and phonate an 'ah'. 2. Gently depress the tongue with a tongue blade. 3. Guide a swab over the tongue into the posterior oropharynx. 4. Using a gentle back-and-forth sweeping motion, swab the area behind the uvula and between the tonsillar pillars. 5. Withdrawal the swab; place swab into the same tube of Viral Transport Medium that contains the nasoparyngeal swab. Specimens should be transported to the laboratory as quickly as possible after collection. When immediate transport is not possible, refrigerate the specimens or keep them on wet ice. For delays of more than 24-48 hours (e.g., when shipping specimens from an outside facility), specimens should be processed as needed and rapidly frozen to -70C and then transported to the laboratory on dry ice.
Specimens for molecular testing should not be stored at room temperature or frozen at -20C. This is critical to ensure the stability and amplification of nucleic acids, particularly for the detection of RNA viruses since RNA is unstable and easily degraded by RNAses from the surrounding environment.
Amplification and detection of parechovirus RNA from the highly conserved 5'-untranslated region of the genome using TaqMan real-time PCR technology. This test is performed pursuant to an agreement with Roche Molecular Systems, Inc.
If positive, results are reported as parechovirus RNA detected.
Negative or no parechovirus RNA dtected
Human parechoviruses are small, RNA viruses related to, but genetically distinct from, the enteroviruses commonly seen in our pediatric population. Similar to enteroviruses, infections with parechoviruses are frequent and significant in infants and young children. The spectrum of clinical diseases is comparable to that of the enteroviruses and includes acute respiratory and gastrointestinal illnesses, neonatal sepsis, aseptic meningitis, encephalitis, myocarditis, acute flaccid paralysis, and necrotizing enterocolitis. Detection of parechovirus by PCR may be enhanced by collecting specimens from multiple body sites. These may include CSF, urine, blood, respiratory, stool, tissue (e.g., colon, myocardium), and sterile body fluids (e.g., pericardial fluid). For diagnosis of neonatal sepsis, send both blood and urine as primary sources; also send CSF, respiratory, and stool samples if symptoms of central nervous system (CNS), respiratory and/or gastrointestinal involvement. Send CSF as the primary specimen in patients with aseptic meningitis or other CNS diseases; also send blood and urine on all patients with CNS disease to increase the likelihood of finding the virus. In addition, respiratory and stool samples may be sent on patients with respiratory and/or gastrointestinal symptoms. Please Note: Despite studies showing respiratory and gastrointestinal symptoms in association with parechovirus infections, the role of this virus in causing respiratory or enteric disease has not been fully established and positive results from only respiratory and stool specimens may not always correlate with disease because of prolonged viral shedding.