Laboratory Testing Guidance

For Pediatric Patients with Acute Hepatitis

A clinical workup for children with acute hepatitis should be done locally per treating clinicians.

CDC recommends testing for Adenovirus and past SARS-CoV-2. Specimens should be tested locally to ensure the most timely results for patient care. SARS-CoV-2 serology results should not have an impact on patient care.

Any clinical specimens that need additional diagnostic testing should be submitted to your State Public Health Laboratory (SPHL).

Specimens must also include two primary patient identifiers on the specimen container, in compliance with CLIA regulations, in case additional diagnostic tests are needed. Acceptable primary patient identifiers include:

    • Full patient name (First and last name)
    • Date of birth
    • A unique ID from the time of specimen collection (secondary unique identifiers do not qualify, such as a state public health lab ID)
SPHL ONLY: Ship specimens to CDC on dry ice Mondays-Thursdays.

Ship to CDC on dry ice Mondays-Thursdays (i.e., to arrive at CDC Tuesday-Friday).

Once received by CDC, typing results will be reported back to the SPHL within 2 weeks for any specimens submitted as adenovirus positive.

Diagnostic Adenovirus Testing

Types of Samples needed:

  • Blood specimen collected in purple top EDTA tube (whole blood, plasma) or serum; whole blood is preferred to plasma or serum
    • Nucleic acid amplification testing (NAAT, e.g. PCR) is preferred for adenovirus detection. Testing whole blood by PCR may be more sensitive than testing plasma or serum by PCR and is preferred.
    • DO NOT freeze the whole blood for diagnostic PCR testing.
    • Specimens should be packaged in compliance with IATA regulations for submission of diagnostic samples.
  • Respiratory specimen (nasopharyngeal swab in VTM/UTM, sputum, or bronchioalveolar lavage [BAL])
  • Stool specimen (or rectal swab in VTM/UTM); whenever possible, a stool specimen is preferred to a rectal swab
  • If a liver biopsy has already been performed as clinically indicated, or from native liver explant or autopsy:
    • Formalin-fixed, paraffin embedded (FFPE) liver tissue
    • Fresh liver tissue, frozen on dry ice or liquid nitrogen immediately or as soon as possible, and stored at ≤ -70°C
  • If any adenovirus isolates are received or obtained through the culturing of clinical specimens related to the pediatric hepatitis cases, please notify CDC (ncirddvdgast@cdc.gov and respvirus@cdc.gov) for instructions on submission and additional characterization.
Adenovirus Typing

Adenovirus typing is a surveillance-use only test. Results will be reported back to the SPHL only.

  • Aliquot for adenovirus typing (minimum volume = 0.5 mL)
  • Store frozen (use ≤ -70°C if available).
  • Submit specimens on dry ice to your state public health laboratory, including any local test results and a notification that these specimens are associated with the “Adenovirus/Hepatitis Investigation in Children.”
  • Notify your State Epidemiologist POC and CDC (ncirddvdgast@cdc.gov and respvirus@cdc.gov) when you have specimens available from PUIs associated with this investigation.
    • CDC will provide detailed shipping instructions once notified.
    • Make sure to denote the diagnostic test results for adenovirus of each specimen, to ensure that adenovirus-positive specimens are properly identified for typing.

Do NOT send specimens until pre-approval is received from CDC.

ATTN: STATT LAB
C/O UNIT 84
Respiratory Viruses Diagnostic Laboratory/DVD
Centers for Disease Control and Prevention
1600 Clifton Road, NE
Atlanta, Georgia, 30329

SARS-CoV-2 Serology Testing

For epidemiologic purposes, test for past SARS-CoV-2 infection in children with acute hepatitis.

  • Consider collecting and submitting the following specimen types (if available) for SARS-CoV-2 detection.
  • Serology testing can identify past SARS-CoV-2 infection by detecting the presence of SARS-CoV-2 antibodies in serum or plasma components of blood.
  • SARS-CoV-2 serology testing of plasma/serum are for surveillance-use only.
  • Blood specimen collected in purple-top EDTA tube (plasma), gold-top or tiger- top tubes (serum)
  • Stored frozen (use ≤ -70° if available).
  • Submit specimens on dry ice to your state public health laboratory, including any local test results and a notification that these specimens are associated with the “Adenovirus/Hepatitis Investigation in Children.” Notify your State Epidemiologist POC and CDC (ncirddvdgast@cdc.gov and respvirus@cdc.gov) when you have specimens available from PUIs associated with this investigation.
    • CDC will provide detailed shipping instructions once notified.
    • Make sure to denote the diagnostic test results for adenovirus of each specimen, to ensure that adenovirus-positive specimens are properly identified for typing.

Do NOT send specimens until pre-approval is received from CDC.

ATTN: STATT LAB
C/O UNIT 223
Respiratory Viruses Immunology Team/DVD
Centers for Disease Control and Prevention
1600 Clifton Road, NE
Atlanta, Georgia, 30329

Formalin-fixed, paraffin-embedded (FFPE) fixed liver tissue samples

If a liver biopsy has already been performed as clinically indicated, or from native liver explant or autopsy:

FFPE liver tissue can be submitted to CDC’s Infectious Diseases Pathology Branch (IDPB) for additional pathologic characterization and infectious disease testing including for adenovirus and SARS-CoV-2.

Please follow the instructions provided below, and DO NOT ship FFPE tissue specimens without first contacting pathology@cdc.gov and receiving pre-approval.

FFPE tissue specimens SHOULD be sent at ambient temperature or on cold packs during summer months to prevent melting. FFPE tissue specimens SHOULD NOT be sent on dry ice.

  • Acceptable sample criteria:
    • formalin-fixed, paraffin embedded (FFPE) liver tissue specimens that demonstrate histopathologic evidence of hepatitis, have been submerged in formalin for ≤2 weeks prior to embedding in paraffin

AND

    • are collected from pediatric patients with hepatitis of unknown etiology meeting the current outbreak case definition.
  • In order to perform adenovirus PCR and SARS-CoV-2 RT-PCR, submission of FFPE tissue blocks is required. Unstained slides are not acceptable for molecular (PCR) testing, and tissue scrolls are not acceptable for any testing at IDPB.  For more information, see: Pathologic Evaluation of Fixed Tissues for Possible Infectious Etiologies (CDC-10365)
  • Liver biopsies may be small specimens. To maintain specimen integrity, we recommend existing FFPE tissue blocks be submitted as is, and not be split, which might further reduce available tissue in the block.  FFPE tissue blocks that have been depleted due to removal of tissue sections from the block are not acceptable for testing and will be rejected.
  • Please contact CDC’s IDPB (pathology@cdc.gov) upon receiving tissue specimens, for pre-approval and specific submission instructions. Do not send specimens until pre-approval is provided by pathology@cdc.gov.
Page last reviewed: June 23, 2022