Introduction

Schistosomiasis (aka Bilharziasis) is the second most common parasitic disease in the world after malaria.¹ The disease is particularly common in Africa, which contributes to 80%–90% of cases.² In this article, we present a rare case of S. haematobium in a patient who immigrated from Sudan to the U.S. several years ago.

Case Presentation

AW is a 45-year-old female–otherwise healthy–who came to our urology clinic for a second opinion. The patient presented with the symptoms of dysuria and right flank pain of 1-year duration. The patient also endorsed symptoms of urinary frequency every hour and nocturia 4 times/night. She denied gross hematuria and other storage or voiding lower urinary tract symptoms. There was no fever or other constitutional symptoms. The patient never smoked before. She immigrated from Sudan at the age of 28. She denied personal or family history of genitourinary cancer.

The physical examination (including pelvic examination) was unremarkable, urine analysis was negative and the postvoid residual volume was 53 ml.

Renal function tests were normal. Urine cytology and urine culture were normal. A prior computerized tomography scan showed minimal right hydronephrosis with both distal ureters dilated, and calcifications at the bladder wall and the ureterovesical junctions. Lasix renal scan was negative for obstruction and with normal radiotracer uptake and excretion by both kidneys. Cystoscopy with the patient’s prior urologist reported bladder calcifications at the anterior bladder wall and the trigone. Patient reported failed prior empiric course of antibiotics as well as phenazopyridine. Patient failed amitriptyline as well.

Given the patient’s remote immigration history and the findings of bladder and distal ureteral calcifications, schistosomiasis was suspected. Cystoscopy with ladder biopsy was performed. Cystoscopy showed the typical “sandy patches” pattern of submucosal calcified bilharzial ova (fig. 1). This was confirmed with histopathology showing dead calcific ova of S. haematobium (fig. 2). The patient was given 2 courses of praziquantel.

Figure 1. Cystoscopy showing calcific mucosal lesions at anterior bladder wall referred to as “sandy patches.”

Figure 2. A and B, hematoxylin and eosin slides showing numerous round to oval calcifications identified in lamina propria. B, spikes at tip of oval calcifications are typical for S. haematobium ova.

Discussion

Schistosomiasis is a common parasitic disease especially in Africa and the Middle East. There are 4 types of schistosomiasis: S. haematobium, S. mansoni, S. japonicum and S. intercalatum. S. haematobium is the most common type of schistosomiasis in the genitourinary tract.³ The S. haematobium bladder lesions are directly related to the schistosoma eggs laid by the schistosoma adult couples residing in the peri-vesical venous plexus. These bladder lesions can be precancerous leading to squamous cell carcinoma of the urinary bladder.^4,5 Therefore, regular bladder surveillance is indicated using cystoscopy. Even though it is rare in the U.S., S. haematobium should be suspected in patients who immigrated from areas where this disease condition is common. This is regardless of how remote the immigration was given the fact the course of the disease can last for decades. The presence of bladder and ureteral calcifications is one of the classic findings. Bladder biopsy confirms the diagnosis in cases with visible lesions during cystoscopy. Praziquantel (40 mg/dg) can be initially tried as a form of treatment. It should be noted, however, that praziquntel does not reveres already existing lesions. Bladder mucosal fulguration, resection of bladder lesions and partial cystectomy can be attempted in refractory cases. If the S. haematobium bladder lesions evolved into malignancy, the updated bladder cancer management clinical guidelines should be followed.