Management of a renal calculus larger than 4 cm in a patient with tuberous sclerosis complex-associated angiomyolipoma
A 65-year-old man was admitted to our department with left flank dullness. He was previously diagnosed with TSC after being identified with the typical features, such as dermatological lesions (facial angiofibroma, ungual fibromas, and hypomelanotic macules on the toes), subependymal nodules, and multiple AMLs in both kidneys. While there was no family history of TSC, the patient had childhood epilepsy. He also experienced two episodes of hypovolemic shock concomitant with extensive retroperitoneal hemorrhage caused by spontaneous AML rupture, once in each kidney. Following the second episode, which occurred in the left kidney, he developed sepsis caused by Staphylococcus aureus, which was isolated from both venous blood and urine. He received conservative therapy without blood transfusion for both episodes of rupture.\nAbdominal palpation revealed bilateral kidney enlargement without tenderness. Blood counts were within normal limits except for a low red blood cell count (331 × 104/mm; normal, 430 × 104–570 × 104/mm), low hemoglobin (9.5 g/dl; normal, 13.5–17.0 g/dl), and a low hematocrit value (30.4%; normal, 40%–50%). Serum creatinine level was 1.0 mg/dl (normal, 0.6–1.1 mg/dl). Urinalysis demonstrated sterile pyuria with a negative urine culture. Kidney–ureter–bladder (KUB) radiography revealed a 43 × 16 mm renal calculus in the left kidney []. Intravenous pyelography revealed that the calculus filled the pelvis and lower calyx, causing dilatation of the upper calyx []. Abdominal enhanced computed tomography (CT) demonstrated a significant bilateral renal AML burden in addition to the renal calculus in the left kidney []. We decided to remove the renal calculus for several reasons, including the present clinical symptoms and a previous history of urinary tract infection. Minimally invasive retrograde F-URS with holmium laser lithotripsy was chosen because multiple renal AMLs have hemorrhagic potential.\nA 6.9-Fr F-URS, a 10-Fr ureteral access sheath, and a 200-μ holmium: YAG laser fibers were used for treatment. We attempted to vaporize the stone by “painting” the laser fiber over the stone surface. A 1.9-Fr nitinol basket, which minimizes the loss of deflection during F-URS, was used to extract large fragments and reposition them from the lower pole calyx into a position more readily accessible by the laser fiber, such as the renal pelvis or upper pole calyx. Complete stone fragmentation was achieved and a 4.8-Fr double pigtail stent was inserted. Total surgical duration was 195 minutes. The stone was composed of calcium phosphate. No evidence of greater than 2-mm residual stones was observed before removal of the ureteral stent in postoperative KUB radiography. On postoperative day 5, the stent was retrieved using the tether suture. Postoperative course was uneventful with gradual disappearance of clinical symptoms. Three months after surgery, KUB radiography confirmed the absence of any residual stones [], and urinalysis was also revealed normal findings.