Pediatric renal calyceal diverticular calculi: Diagnostic and management by percutaneous nephrolithotomy “case report”

Abstract

Renal calyceal diverticula are rarely diagnosed in children. Calculus formation within the diverticulum is a significant complication and its management in children remains controversial. We report our experience with 1 case, managed with minimally invasive surgery.

We report one pediatric case who presented with flank pain. Physical examination, biochemistry and urinalysis were normal. Contrast-enhanced computed tomography revealed calyceal diverticulum type II with secondary diverticular calculus. The patient underwent mini-percutaneous nephrolithotomy and recovered uneventfully.

Percutaneous nephrolithotomy is safe and effective, and it can be offered as a first line therapy for symptomatic calyceal diverticular calculi in children.

1 Introduction

Calyceal diverticulum (CD) refers to a cystic cavity covered with the transitional epithelium in the renal parenchyma that is connected to the renal calyx or renal pelvis through a narrow isthmus. CD are rarely diagnosed in children. Although rare, these cavities can lead to significant complications including calculus formation, urinary tract infection, abscess formation and hypertension. It has been estimated that 9.5 %–50 % of CD develop calculi. Management of calyceal diverticular calculi in children remains controversial. Here, we report the case of 1 pediatric patient with calyceal diverticular calculus diagnosed and managed in Medanta, the Medicity hospital.

2 Case presentation

A non-obese 15-year-old Indian girl presented to our outpatient urology clinic with the primary complaint of intermittent right flank pain with the last episode occurring two months prior to admission. She had no other symptoms. She had no history of haematuria, dysuria and urinary tract infections. The first episode of right flank pain occurs 8 years ago (7 years old); she was treated with alternative medicine affording temporary relief of pain. Her family history was negative for any renal cystic disease, familial syndromes, or known genitourinary abnormalities. Her physical examination was normal without abdominal mass or tenderness. Urine tests and biochemistry were normal. Ultrasound examination ( Fig. 1 ) showed that middle calyx of the right kidney is dilated with a narrow communication with similar cyst towards the hilum. Together they measure 2.8 × 1.6 cm. A calculus measuring 5 mm is seen in the dilated calyx. For further evaluation, contrast-enhanced computed tomography urography (CTU) and Technetium-99m diethylene triamine pentaacetic acid (Tc-99m DTPA) diuretic scan were carried out. CTU demonstrated focal dilatation in the midpole of the right kidney of two middle calyces/CD, together measuring 3.2 × 1.7 cm with a small dependent calculus in the medial calyx measuring 4 × 2 mm ( Fig. 2 ). Tc-99m DTPA diuretic scan demonstrated a good functioning of the kidneys with left kidney 51 % and right kidney 49 %. A conservative management was first conducted to follow the natural evolution in case it was favourable. After 18 months of observation, recurrent episodes of flank pain persisted. A contrast-enhanced magnetic resonance urography (MRU) confirmed a bilobed cystic lesion seen in the right kidney interpolar region posteriorly, the medial measuring 2× 1.5 cm and the lateral measuring 2 × 1.3 cm ( Fig. 3 ). The lateral cyst shows dependent debris/calculus measuring 14 × 6 mm. So, both the CD (1.4 cm–2 cm) and the calculus (5 mm–14 mm) increased in size. Surgical intervention was therefore indicated. The patient underwent endoscopic percutaneous nephrolithotomy (PCNL) ( Fig. 4 ). The patient was first placed in lithotomy position. Cystoscopy was done and, right ureter cannulated and 6Fr ureteric catheter was placed. 14Fr urinary catheter was placed. The patient was then turned to prone position. Puncture was taken into the right CD, and the tract dilated till 16Fr. 15Fr Amplatz sheath was placed. Nephroscopy was done and stone removed ( Fig. 5 ). Opening of the diverticulum was dilated with balloon dilator which can allow 12Fr scope 5/24 Fr. Double j stent was inserted. The procedure was uneventful. The JJ stent was in place for 6 weeks. No flank pain or other abnormalities were noted at the 4-months postoperative follow-up. The follow up will be strictly pursued for a long period of time to ensure that the dilation of the infundibulum of the calyx is durable.