Left renal hydatid cyst presenting as hematuria and macroscopic hydatiduria since last ten years.

Renal hydatidosis represents only 2-3% of hydatid disease. It is endemic in parts of eastern Europe, middle East, south America, Australia, New Zealand, Alaska, and Canada. Cystic rupture into the collecting system causes hydaturia; isolated renal involvement is even rarer. Here we report a case of left renal hydatid cyst in a 40 year old man presenting as hematuria and macroscopic hydaturia since last ten years. The patient underwent exploratory laparotomy and recovered.

INTRODUCTION

Renal hydatidosis represents only 2-3% of hydatid disease. The clinical features of renal hydatid are mass in the flank, renal colic, persistent fever, hematuria, dysuria, pyuria, renal stones, or hypertension. Cystic rupture into the collecting system causes hydatiduria, seen in only 10-20% of renal hydatid and is usually microscopic. Gross passage of the daughter cyst is rather uncommon.[1] The diagnosis of the primary hydatid cyst of the kidney is usually radiological, most patients have negative immunological tests. It is endemic in parts of Eastern Europe, Middle East, South America, Australia, New Zealand, Alaska, and Canada.[23] Hydatid disease is caused by the cestode Echinococcus granulosus. Isolated renal involvement is even rarer. A late diagnosis due to uncommon clinical manifestations is considered to be the main reason for the loss of the organ.[12]

We present a case of a 40-year-old male, with isolated renal hydatid with hydatiduria, a very rare presentation, and its management by transperitoneal enucleation of the hydatid cyst. Gross hydatiduria is a very rare presentation of hydatidosis as seen in our case.

CASE PRESENTATION

A 40-year-old male presented with colicky abdominal pain for 10 years and intermittent passage of small, white grape-like structures in the urine [Figure 1] along with intermittent hematuria; whenever he passed the daughter cyst in urine he was relieved. He was taking analgesics on feeling of pain. He came for admission as the pain had subsided but there was dysuria and nausea. On systemic examination, the abdomen was normal. Hemogram was normal and liver function tests were within normal limit, blood urea was 55 mg/dl and serum creatinine was 1.7 mg/dl. The chest X-ray P-A view was normal.

Figure 1

CT scan showing hydatid cysts present in upper pole of Kidney

Ultrasonography revealed a multiseptate cyst in the left kidney. The left kidney was compressed by cysts with splitting of the pelvicalyceal system. The right kidney was normal in size and echotexture, liver was normal. The computed tomography (CT) scan revealed a cystic lesion in the upper pole of the left kidney [Figure 2] and the upper ureter. The excretion of contrast was normal from both the kidneys. The patient was started with albendazole. After 1 week, the patient underwent exploratory laparotomy, descending colon was mobilized, and left kidney [Figure 3] was exposed, and a hydatid cyst was located [Figure 4]. The hydatid cyst was laid open after instillation of the cetrimide solution and 176 small and large daughter cysts [Figure 5] were taken out of the cavity, the cavity was capitulated as we do after excision of lung hydatid. The patient was discharged after 8 days and was advised albendazole 400 mg BD for 4 weeks.

Figure 2

Hydatid cyst excreted in urine

Figure 3

Normal kidney and a hydatid cyst wall at upper pole of kidney

Figure 4

Incision made over a hydatid cyst showing daughter cysts

Figure 5

Photograph of some of the hydatid cyst

DISCUSSION

Hydatid disease, also known as echinococcosis, is caused by infection with the larva of the tapeworm of the genus Echinococcus.[3] The two most common organs involved are the liver (65%) and the lungs (25%). Other less common sites are bones 5%, kidney 3%, spleen 2%, heart 1%, pancreas 1%, and central nervous system 1%.[23] Renal hydatid cysts usually remain asymptomatic for years. However, the patient may present with renal pain, hematuria, pyuria, and intermittent fever. Rupture of the cyst into the renal collecting system causing hydatiduria is pathognomonic and is seen in only 10-20% of the renal hydatidosis. It is usually microscopic. Macroscopic hydatiduria is very rare.[2]

Serology and imaging modalities establish the diagnosis in most of the cases.[4] Serology consists of immuno-electrophoresis, immuno-hemagglutination test, and complement fixation test. The Casoni test is unreliable and outdated. A combination of investigations yields a diagnosis in only 50% of cases.[3] The enzyme-linked immunosorbent assay is the most widely used assay. The confirmatory test is arc 5 immunoelectrophoresis. It detects antibodies against immune-dominant and specific antigen, antigen 5 of the cestode. A polymerase chain reaction (PCR) using a recombinant DNA antigen is useful in defining the particular species of Echinococcus. Abdominal ultrasonography and CT scan are wonderful in establishing the diagnosis of hydatid disease.[4] Magnetic resonance imaging (MRI) has no real advantage over CT scan. Accuracy and sensitivity of CT scan is better as compared to ultrasonography (USG).[2] USG helps in the diagnosis of hydatid cysts when the daughter cysts and hydatid sand are demonstrated. On changing the patient's posture under real time, there is shifting of hydatid sand, which may give rise to the “falling snowflake pattern”.[23] Intravenous Urogram must be done to rule out, a communication with renal ductal system and functioning of both the kidneys.[3]

In general, surgery is the treatment of choice in renal hydatid cyst. Kidney-sparing surgery is done in 75% cases.[4] Nephrectomy is a last resort in 25% of cases. Utmost care should be taken during the surgery to prevent spillage which may result in disseminated hydatidosis. Pre- and postoperative one-month courses of albendazole should be considered in order to sterilize the cyst, decrease the chance of anaphylaxis, and reduce the tension in the cyst wall (thus reducing the risk of spillage during surgery) and to reduce the recurrence rate postoperatively. During kidney-sparing surgery, scolicidal solutions such as hypertonic, cetrimide, povidone iodine should be used before opening the cavities to kill the daughter cysts and therefore prevent further spread or anaphylactic reaction.[25] Surgical management consists of various options. Total excision consists of either wedge resection or partial nephrectomy and partial excision includes partial pericystectomy followed by capitonnage.[3] It is recommended to start the patient on a course of oral albendazole after surgery.[4] The treatment is mainly surgical and with appropriate diagnosis and treatment, prognosis is good.[5]

We believe from our experience with transperitoneal approach that transperitoneal approach gives a better working space, which helps us to remain outside Gerota's fascia and prevent subsequent cyst rupture. But cases have been reported where renal hydatid cysts had been removed retroperitoneally.