Glomerulocystic disease

Glomerulocystic disease (GCK) is a rare cystic kidney disease.

Pathology

Microscopic appearance

Histopathology typically shows normal-sized glomeruli with the enlarged Bowman’s space and tubular cystic changes. A proposed mechanism of glomerular cyst development is stenosis at the glomerulotubular junction but the exact mechanism is still unknown.

Classification

• familial nonsyndromic, e.g. autosomal dominant polycystic kidney disease in young infants
• associated with inheritable malformation syndromes, e.g. tuberous sclerosis complex
• syndromic, non-Mendelian, e.g. trisomy 9, 13, or 18
• sporadic, e.g. new mutations
• acquired and dysplastic kidneys, e.g. obstructive uropathy 

Associations

Following syndromic associations have been proposed :

• Down syndrome
• asplenia with cardiovascular anomalies
• multiple acyl-CoA dehydrogenase deficiency
• Jeune syndrome
• Marden-Walker syndrome
• maturity-onset diabetes of the young
• Meckel-Gruber syndrome
• medullary cystic kidney disease
• nephronophthisis
• orofaciodigital syndrome - type I
• phocomelia syndrome (Robert/pseudothalidomide syndrome)
• short-rib-polydactyly syndrome
• Smith-Lemli-Opitz’s syndrome
• tuberous sclerosis complex
• Zellweger’s cerebrohepatorenal syndrome

Radiographic features

Appearance of the cysts are like any other cyst in the body. However, the cortical distribution will aid in the diagnosis.

Ultrasound

Ultrasound usually demonstrates bilateral echogenic kidneys with loss of corticomedullary differentiation . Small cortical cysts may be visualized .

CT

CT demonstrates bilateral multiple cysts that are hypoattenuating and typically in the subcapsular location .

MRI

MRI shows marked bilateral renal enlargement with multiple small (~1 cm) cortically-based cysts that are T1 low signal and T2 high signal.

The renal cortices have a uniform T1 low signal with a loss of the normal corticomedullary relationship. On T2WI, the cortex shows high signal similar to that of the medulla. These findings probably reflect the predominance of numerous minute cysts in the cortex, which is an important morphologic feature of GCK.

Hypointensity of the renal cortex alone has been described in multiple diseases but cortical hypointensity on T1 with loss of corticomedullary differentiation and numerous/innumerable cortical-based small cysts is considered pathognomic for glomerulocystic disease .

History and etymology

In 1941, Roos described an infant with cystic glomeruli who was affected by rickets, and renal failure .The term glomerulocystic disease was first coined by Taxy and Filmer .