[Cacchi and Ricci's disease. Radiology, epidemiology and biology].

Area of Science:

• Radiology
• Nephrology
• Urology

Background:

• Medullary sponge kidney (MSK) is a congenital renal abnormality characterized by cystic dilatation of the medullary and papillary portions of the renal tubules.
• It is often associated with renal stones and other urinary tract complications.

Purpose of the Study:

• To highlight the radiological, epidemiological, and laboratory features of medullary sponge kidney.
• To evaluate the diagnostic utility of early urography films in identifying MSK.

Main Methods:

• Review of 500 cases with radiopaque renal stones (310 men, 190 women) and 100 North African cases.
• Analysis of urography, early urographic films, blood calcium/phosphate, and 24-hour urinary calcium/oxalate levels.

Main Results:

• Early urography films (2-4 minutes post-injection) effectively visualize abnormal renal pyramid opacification, aiding MSK diagnosis.
• A novel radiological sign, a clear border between papillae and calices opacification, was identified.
• MSK diagnosed in 20.6% of renal stone cases (higher in women: 27.89% vs. men: 12.59%).
• Hypercalciuria (59.22%) and hyperoxaluria (64.08%) were common, with 39.81% exhibiting both.
• Low MSK incidence (3 cases) noted in North African subjects.

Conclusions:

• Early urography films, particularly with the identified clear border sign, are crucial for MSK diagnosis.
• MSK is significantly more prevalent in patients with radiopaque stones, especially women.
• Hypercalciuria and hyperoxaluria are frequent metabolic abnormalities associated with MSK.