Ordering Recommendation

Acceptable test for molecular confirmation of suspected clinical diagnosis of autosomal dominant polycystic kidney disease (ADPKD).

Mnemonic
ADPKD FGS
Methodology

Polymerase Chain Reaction/Sequencing

Performed

Sun-Sat

Reported

28-35 days

New York DOH Approval Status
Specimens from New York clients will be sent out to a New York DOH approved laboratory, if possible.
Specimen Required
Patient Preparation
Collect

Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).

Specimen Preparation

Transport 3 mL whole blood. (Min: 1 mL)

Storage/Transport Temperature

Refrigerated.

Unacceptable Conditions
Remarks
Stability

Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable

Reference Interval
Interpretive Data

Background Information for Polycystic Kidney Disease, Autosomal Dominant (PKD1 and PKD2) Sequencing
Characteristics:
Autosomal Dominant Polycystic Kidney Disease (ADPKD) is typically an adult-onset, multisystem disorder. Renal findings include: bilateral renal cysts, renal insufficiency, renal pain, hypertension, dilated renal tubules, enlarged kidneys, and end-stage renal disease (ESRD). Extra-renal findings include cysts in other organs, including liver, pancreas, seminal vesicles, and arachnoid membrane. Connective tissue findings include intracranial aneurysms, dolichoectasia, dilation of the aortic root, aortic dissections, mitral valve prolapse, and abdominal wall hernias. Fifty percent of individuals with ADPKD will develop ESRD by age 60.
Prevalence: 1:500-1:1,000 in the U.S.
Inheritance:  Autosomal dominant; 5-10 percent of cases are de novo.
Penetrance:  Age-dependent; nearly all older adults develop multiple renal cysts. The average age of onset for ESRD in individuals with PKD1 and PKD2 mutations is 54 and 74 years, respectively.
Cause: Pathogenic PKD1 or PKD2 gene mutations. In cases with an identifiable molecular cause, 85 percent are attributed to PKD1 and 15 percent are attributed to PKD2.
Clinical Sensitivity:  Estimated at 87 percent for ADPKD.
Methodology: Bidirectional sequencing of the entire coding region and intron/exon boundaries of the PKD1 and PKD2 genes. A large region of PKD1, including exons 1-33, is duplicated six times on the same chromosome; therefore, to distinguish the PKD1 gene from the PKD1-like pseudogenes, long range PCR followed by site-specific PCR is used to sequence PKD1 exons 1-33.
Analytical Sensitivity and Specificity: 99 percent.
Limitations:
  Diagnostic errors can occur due to rare sequence variations. Large deletions/duplications, regulatory region mutations and deep intronic mutations in PKD1 or PKD2 will not be detected. Mosaic mutations in PKD1 or PKD2 may not be detected. Mutations in genes other than PKD1 and PKD2 are not assessed by this assay.

Compliance Category

Laboratory Developed Test (LDT)

Note
Hotline History
N/A
CPT Codes

81406; 81407

Components
Component Test Code* Component Chart Name LOINC
2012256 ADPKD Sequencing Specimen 31208-2
2012257 ADPKD Sequencing Interpretation 44421-6
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • ADPKD
  • Adult polycystic kidney disease (APKD)
  • Autosomal dominant polycystic kidney disease
  • Polycystic kidney disease type 1
  • Polycystic kidney disease type 2
Polycystic Kidney Disease, Autosomal Dominant (PKD1 and PKD2) Sequencing (Temporary Referral as of 06/09/20)