歐穎倫 吳勝堂 高建璋

三軍總醫院外科部泌尿外科

Ying-Lun Ou, Sheng-Tang Wu ,Chien-Chang Kao

Division of Urology, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, R.O.C.

 

Introduction: Autosomal dominant polycystic disease (ADPKD) is globally the third most common cause of end stage kidney disease (ESKD). Mutations in two genes cause ADPKD had been identified: PKD1 accounts for 80–85% of patients and PKD2 accounts for 15–20% [1]. Renal failure requiring for renal replacement therapy (RRT) occurs in approximately 50 % patients, and mostly in their fourth to sixth decades[2]. The common presentation include hypertension, hematuria, polyuria, flank pain, flank mass, kidney stone, and repeated urinary tract infection. Other extra-renal manifestations included left ventricular hypertrophy, hepatic cysts, seminal vesicle cysts, intracranial aneurysm, aortic root dilatation and aneurysm, diverticulosis, and abdominal and inguinal hernias[3] [4].

Recent study revealed that there were estimated 21% of the PKD patient on dialysis experienced kidney complications, mainly cystic infection[5]. Another research estimated that 30% to 50% patient have some sort of kidney infection during their life time[6]. Infected cyst and acute pyelonephritis are the most common kidney infection. The Cyst infection is a diagnostic challenge because of the lack of specific manifestations. The image modality, such as sonogram, CT, or MRI is sometimes hard to differentiate the cystic lesion with infection or not. On the whole, cyst infection accounts for 15% of all causes of hospitalizations of ADPKD patients, and is diagnosed when confirmed by cyst aspiration showing neutrophils and bacteria, but the identification of the causative germ is lacking in more than half of cases[7].

Case report: A 49-year-old man who was referred from another regional hospital in March because of persistent nausea, vomiting, abdominal distension, and high fever.

The patient had been diagnosed of Autosomal dominant polycystic kidney disease (ADPKD) for 10 years, status with end stage renal disease, and had been receiving regular hemodialysis for 8 months before admission.

   However, his condition deteriorated, the abdomen grew bigger and bigger day by day. The nausea and vomiting progressed which NG-tube insertion was needed for decompression. Visible hematuria and high fever persisted, and failed with medical treatment. Under impression of ADPKD with cystic infection, mimic abdominal compartment syndrome, he was then transferred to our center (March 09).

At presentation, the abdomen is full and extended, dull percussion sound over the bilateral region, and hyper-active bowel sound was noticed, but with no marked tender point. The temperature was 38.4°C, the blood pressure 124/78 mm Hg, and the pulse 82 beats per minute. The abdomen was distended, huge mass was palpable especially over the bilateral flank but the edge was hard to identified, dull percussion sound, but without marked tender point.

    After the operation, his fever and the abdominal discomfort seemed improved progressively without changing the antibiotic regimen, no major complication following after the operation. Then, due to his improved condition, no fever presented, and the surgical wound healed well the following two weeks, his was then discharged on April 01.

 

Discussion : ADPKD complications are directly related to the extent of renal cyst involvement. Hematuria occurs in 35–50% of patients from cyst rupture. Kidney stones can occur in 20% of patients. Flank pain may be caused by cyst or parenchymal infections, nephrolithiasis, or cyst hemorrhage[8].

Cyst infection represents a serious complication of ADPKD. We should started with proper empirical antibiotics first. Pathogens usually include enteric flora, Escherichia coli being the most common agent[7].

The radiologist should be consulted for percutaneous drainage, because the antibiotics alone may be ineffective that the patient are often oliguric, even anuric, which lead to poor penetration of antibiotic to the infected cyst. Thus, cyst drainage may be indicated for diagnostic and therapeutic purpose [9].

If the combination of antibiotics and the cyst drainage failed, or not performable due to certain reasons as our case, nephrectomy should be taken into consideration.

Laparoscopic nephrectomy offers an effective alternative to open nephrectomy[10]. But patients with massive polycystic kidneys with a kidney volume of greater than 3,500 cc are at increased risk for open conversion[11].

There is also a recent protocol, hold by The Cochrane Collaboration, aimed to find out the best medical and surgical treatment for the infected cysts in people with ADPKD.[12]

Percutaneous drainage, or surgical unroofing may be the choice prior to nephrectomy. But, if presentation with polycystic infection, or the cystic kidney is too large that the targeted infected cyst may be hampered to access, or high risk of hemorrhage, early nephrectomy should be considered, especially for those presented with end stage kidney disease already.