Megacalycosis: a rare condition

Abstract

Megacalycosis is an extremely rare condition. We report our experience with two cases and discuss its pathogenesis, diagnosis and management in children. Our two patients had presented a prior diagnosis of congenital hydronephrosis. An increased number of calyces with a significant disproportion between the degree of calyceal dilatation and a mildly dilated renal pelvis were found in each case. Megacalycosis must be considered in the differential diagnosis of congenital hydronephrosis, polycalycosis, and infundibular stenosis. The diagnosis is suggested by ultrasound and confirmed by diuretic renography, intravenous pyelography or magnetic resonance urography. Voiding cystourethrography should be performed to rule out vesicoureteral reflux. A high index of suspicion is needed for the diagnosis of this condition.

Radiological findings and the clinical importance of megacalycosis

“…Approximately 100 cases with unilateral or bilateral megacalyces are described in the literature. 1 , 3 , 6 , 10 – 12 Part of them was presented with urinary tract infection or kidney colic. For most cases, however, especially in children, congenital hydronephrosis was falsely supposed.…”

Congenital Megacalycosis with IgA Nephropathy: A Case Report and Review of the Literature

“…3,[5][6][7] This disorder is generally diagnosed during evaluation of nephrolithiasis and/or urinary tract infection. [7][8][9][10][11][12] Obstructive nephropathy and vesicoureteral reflux should be excluded before diagnosing congenital megacalycosis. Ultrasonography, intravenous pyelography, scintigraphy, and computed tomography play important roles in the exclusion of obstructive causes.…”

“…Clinical characteristics of all the reported patients with congenital megacalycosis were shown in Table 1. [7][8][9][10][11][12][15][16][17][18] Renal function of patients with congenital megacalycosis is usually normal both at the time of diagnosis and during follow-up. 12 Slight defects in concentration capacity can be seen due to relative loss of juxtamedullary nephrons.…”

Hydronephrosis or megacalycosis – differential diagnosis of urinary tract obstruction

“…Poszerzenie układu kielichowo-miedniczkowego w badaniu USG może być związane z odpływem pęcherzowo-moczowodowym, zwężeniem podmiedniczkowym lub przypęcherzowym moczowodu oraz obecnością naczyń dodatkowych, które powodują ucisk na moczowód. W badaniach ultrasonograficznych poszerzenie układu kielichowo-miedniczkowego jest zwykle dobrze widoczne, ale jednoznaczne ustalenie przyczyny zastoju moczu w nerce może być trudne [7]. U naszego pacjenta badania USG różniły się pod względem oceny układu kielichowo-miedniczkowego w nerce lewej.…”