Clinical and demographic characteristics of patients with urinary tract hydatid disease

Abstract

Background: Human cystic echinococcosis (CE) is caused by flatworm larvae of Echinococcus granulosus and is endemic in many parts of the world. In humans, CE cysts primarily affect the liver and pulmonary system, but can also affect the renal system. However, the clinical manifestations of renal CE can be subtle, so healthcare professionals often overlook renal CE in differential diagnosis. In this study, we examined the clinical and demographic characteristics of patients with urinary tract CE and analyzed the diagnosis and treatment procedures for this disease.

Methods: The records of 19 consecutive renal CE patients who were admitted to the First Affiliated Hospital of Xinjiang Medical University from January 1983 to April 2011 were retrospectively reviewed. In all cases, CE of the urinary tract was confirmed by pathological examination and visual inspection during surgery.

Results: Fifteen patients were males and 4 were females. The most common symptoms were non-specific lower back pain and percussion tenderness on the kidney region. All patients were followed up for 9-180 months after surgery. None of the patients experienced a recurrence of renal CE, but 4 patients experienced non-renal recurrence of hydatid disease.

Conclusions: Hydatid cysts from E. granulosus are structurally similar in the liver and urinary tract. Thus, the treatment regimen for liver CE developed by the World Health Organization/Informal Working Group on Echinococcosis (WHO/IWGE) could also be used for urinary tract CE. In our patients, the use of ultrasound, computed tomography, serology, and clinical characteristics provided a diagnostic accuracy of 66.7% to 92.3%.

Figure 1. Type CE2 disease in a 17-year-old Uygur female patient.

The patient experienced left lower back pain for three years and pain aggravation for two weeks with nausea. She had no history of exposure to sheep or dogs. Physical examination showed percussion tenderness over the left kidney region. A CT scan (A) showed connection of a CE cyst with the renal pelvis and an enhanced image indicated a thick-walled cystic lesion at the middle outer edge of the left kidney (6.7 cm×3.8 cm) (B). The boundary was clear, soft tissue septum, and multiple daughter vesicles and wall calcifications were also evident. The lesion communicated with the middle calyx and showed no enhancement. The left renal pelvis and calyx were dilated, and there was a patchy shadow of calcification.

Figure 2. Type CE2 disease in a 35-year-old Han male patient.

The patient experienced intermittent fever, shortness of breath, chest tightness, cough, and expectoration of a white-capsule-like substance for one month and aggravation of symptoms for 3 days. He did not experience any itching or palpitation. Physical examination showed dullness on percussion in the right lung and decreased respiratory movement. He underwent two surgeries for hepatic hydatid disease in 1995 and 2003. A CT image showed multiple hydatid cysts in the right lung (A), chest cavity (B), and diaphragm apex. Compression atelectasis of the right lung and a large amount of pleural effusion on the right side was observed. Multiple hepatic hydatid cysts and a renal hydatid cyst with multiple daughter vesicles were also observed.