WAGR Syndrome Workup

Updated: Oct 21, 2022
  • Author: Jacquelyn N Crane, MD; Chief Editor: Max J Coppes, MD, PhD, MBA  more...
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Laboratory Studies

GU abnormalities may lead to reduced renal function early in life. Renal function is rarely affected by nephroblastomatosis alone. 

Consider the following laboratory studies:

  • BUN and/or creatinine levels should be assessed in patients with WAGR syndrome.

  • Findings of protein in the urine should alert the clinician to the possibility of WT1 disorder (including Denys-Drash or Frasier syndromes), which are associated with declining renal function. Blood may be present in the urine when patients present with a Wilms tumor.

  • A CBC count with a platelet count may demonstrate anemia due to blood loss secondary to an enlarging renal mass.

  • Serum calcium levels should be measured.

  • Cytogenetic testing should be performed to confirm the diagnosis. Standard high-resolution chromosome studies may not be able to detect deletions in WT1. The addition of molecular cytogenetic fluorescence in situ hybridization techniques may define the extent of the deletion.


Imaging Studies


Renal ultrasonography is the initial study of choice to confirm the diagnosis of renal pathology in the neonatal period. Note the following:

  • Enlargement of the kidneys usually suggests nephroblastomatosis. The appearance of both kidneys should be documented.

  • Some (internal) GU abnormalities are usually best documented using ultrasonography, although additional imaging tests may be required. [21]

  • A follow-up examination of the kidneys should be performed every 3 months until the patient is aged 7-8 years. Physical examinations should be performed every 6 months until the patient's growth is complete. Baseline CT scanning may be indicated at the time of the initial diagnosis.

  • The presence of an enlarging renal mass suggests the development of a Wilms tumor.

  • Evaluation of the renal vein and inferior vena cava for the presence of tumor thrombi is important for staging, and the study is usually accomplished using renal ultrasonography and/or Doppler imaging.


Chest radiography becomes important in the staging workup once Wilms tumor is diagnosed.

Computed tomography (CT) or magnetic resonance imaging (MRI)

CT scanning of the chest and CT or MRI abdomen may provide further information about the location and stage of the tumor.



The role of a renal biopsy at the time of diagnosis of WAGR syndrome in the neonatal period is controversial. The presence of nephrogenic rests can be demonstrated histologically, but the risk of losing renal function as a result of the procedure may outweigh the need to confirm the diagnosis in a patient with AGR syndrome.

Biopsy findings of kidneys that contain nephrogenic rests or nephroblastomatosis reveal nests of developmentally immature renal parenchyma. Although these rests may be stable over a long period, they generally (1) die and produce a hyalinized remnant, (2) mature into normal renal parenchyma, or (3) produce a Wilms tumor.

In patients with WAGR syndrome presenting with a primary renal mass with clinical situation, age, and imaging highly suggestive of Wilms tumor, upfront chemotherapy without biopsy and surgical resection is recommended followed by delayed surgical resection. [14]