Erosion of repaired exstrophy bladder by a large vesical calculus.

Formation of stones in repaired exstrophy bladder is common; however, erosion of stone through the repaired bladder and anterior abdominal wall has never been reported. We report one such case of erosion after three years of repair.

INTRODUCTION

Urinary calculi formation in exstrophy bladder (EB) patients is reported to be around 15% after bladder closure. In neglected cases the stones may become very large and infected. Very rarely, as in our patient, the stone may erode through the urinary bladder and anterior abdominal wall to be seen over the surface.

CASE REPORT

A 4-year-old male child who had already undergone primary repair of EB at another hospital, at the age of one year, presented to our paediatric surgery outpatient department. He had history of passing purulent urine from the defect in lower abdomen, hematuria and fever with chills intermittently for last ten months. The defect progressively increased in size during this period. A dirty yellowish stone was visible through the defect for two months. Epispadias was not repaired [Figure 1]. The child was not gaining weight. The socioeconomic condition of the child's family was poor and they were illiterate, thereby resulting in poor follow up after initial surgery. On examination, features of sepsis were present in the form of fever, tachycardia and low blood pressure. The upper abdomen was soft. There was a large defect in lower abdomen where a large stone was impacted. Purulent urine could be seen coming from the side of the stone.

Figure 1

The patient, a male child has disrupted repair of exstrophy urinary bladder with a large stone visible in it. Epispadiasis has not been repaired

The patient was resuscitated and investigated. The haemoglobin was 5.6 gm/dl, total leucocyte count was 20,750/cumm, blood urea 126 mg/dl and serum creatinine was 2.7 mg/dl. Serum calcium, phosphate, uric acid levels were normal. The ultrasound abdomen showed bilateral hydroureteronephrosis. Urine culture grew Escherichia coli. The patient was put on antibiotics according to sensitivity testing reports. After transfusion of blood, he was taken up for surgery on a semi urgent basis. The impacted stone in bladder was manipulated and removed [Figure 2]. In view of the poor socioeconomic condition and history of neglect of the child, it was thought that a single stage corrective surgery might me more practical. The parents were counselled regarding the nature and complications of surgery. Urinary bladder was dissected and excised. Both ureters were mobilised and ureterosigmoidostomy was done in an antireflux manner. Postoperatively, the patient improved without any complications, passing urine through rectum. His blood urea and serum creatinine normalized in eight days. Analysis of stone showed presence of calcium, magnesium, ammonium and phosphorus. The patient is on regular follow up for the past 12 months and is well.

Figure 2

The large yellowish stone removed from the urinary bladder after manipulation

DISCUSSION

The exstrophy of bladder is usually repaired in stages.[1] Vesical calculus in EB repaired patients is known to occur.[2] Many of the stones develop on the suture material used for the repair which is mostly nonabsorbable.[3] Bladder neck obstruction with resultant stasis and infection in EB repaired patients predisposes to stone formation. In a study of 530 patients with EB, 15% developed stones; white male population was the most commonly affected group and most calculi formed in the urinary bladder whether native or augmented by enterocystoplasty.[4] It was also noted that the risk of stone formation in EB patients was associated with operative procedures like augmentation cystoplasty and bladder neck procedure to increase the outlet resistance; other risk factors being urinary infection, foreign bodies, vesicoureteral reflux and urinary stasis.

Dehiscence of the repair done in EB patients along with protrusion of stone through the anterior abdominal wall is extremely rare and not reported. This shows an extremely high level of neglect by the parents. Our patient had undergone stage one repair at the age of one year at some other hospital and did not follow at any medical facility due to ignorance, illiteracy and poor socioeconomic condition. He probably developed bladder outflow obstruction leading to stasis, infection and then stone formation. The stone became huge in size and then eroded through the repaired bladder and abdominal wall onto the skin surface. We could not find any suture material in the defect.

The operative procedure we opted for, was excision of urinary bladder and bilateral ureterosigmoidostomy. The decision was opted after taking into account the poor socioeconomic condition of the family and the neglect of the child. This was also helpful to avoid the problem of recurrent stones. We checked for anal tone before surgery to make sure that the child remained continent. The known complications of ureterosigmoidostomy are occasional bowel incontinence at night, nephritis, diarrhoea, hypokalemic acidosis and finally carcinoma colon after long period of time.[56] However, the quality of life in developing countries is a factor worth considering.[7]