WAGR syndrome

WAGR syndrome stands for Wilms’ tumor, aniridia, genitourinary anomalies, and mental retardation, which is now called intellectual disability, and this is a genetic disorder that’s caused when a part of chromosome 11 is missing, or deleted.

Not everyone with WAGR has all of the symptoms, for example only about a half of the individuals have Wilms’ tumor.

On the flip side, some have additional symptoms, too, like progressive kidney failure, growth retardation, small head size, and obesity.

The most specific feature of WAGR syndrome is aniridia, which is the complete or partial absence of the iris, the colored part of the eye. And this is an easily noticeable feature, and it’s present at birth, so it’s usually the first thing to raise suspicion of WAGR syndrome.

Now, a normal iris controls how much light enters the eye, and it constricts the pupil when there’s a lot of light around to keep the vision sharp. With aniridia, too much light gets into the eye, which leads to blurry vision and photophobia, which is discomfort when the eyes are exposed to light.

Additional eye features in WAGR syndrome can include cataracts, which is a clouded lens, glaucoma, or increased pressure in the eye, and nystagmus—abnormal rhythmic eye movements of the eye.

Wilms’ tumor, also called nephroblastoma, is generally a malignant kidney tumor that affects children.

Wilms’ tumor’s composed of metanephric blastema, which is a cell type that’s seen in the developing kidney, stromal cells which are part of the connective tissue, and epithelial cells which self-organize into primitive glomeruli and tubules.

Children with Wilms’ tumor often develop a large flank mass, as well as hematuria, which is blood in the urine, and hypertension.

Now, that hypertension is a result of increased renin secretion; which either comes from the tumor itself or from healthy kidney tissue that secretes renin because it’s physically compressed by the tumor.

It’s worth noting that Wilms’ tumor isn’t specific for WAGR syndrome; in fact, it most commonly happens in otherwise-healthy children, and can be a part of other syndromes like Beckwith-Wiedemann syndrome.