Rare complication muddies the waters
Mr Wong, 71, had spent decades working as a toy factory worker and sailor. After years of toil, he finally retired and could enjoy life at a leisurely pace with few worries. His daughter had grown up and married and was working as a nursing officer at a local hospital, and he enjoyed good health.
The first hint of trouble, however, surfaced when he noticed a red tint to his urine. Wong (whose full name has been withheld for reasons of confidentiality) was worried, but tried to ignore it since he felt no pain. When the reddish hue did not go away after a few weeks, he mentioned it to his daughter.
Although blood in the urine, or haematuria, is a fairly common condition and could be indicative of many conditions, Wong's age was a risk factor for more serious ailments. His daughter insisted he see Professor Anthony Ng Chi-fai, a urologist from Chinese University's department of surgery.
Ng put Wong through a series of tests, including urine screening, computed tomography (CT) scans and a cystoscopy, where a narrow tube with a light and camera on the end is inserted into the bladder through the urethra. Ng found multiple tumours, the largest being four centimetres in diameter, in Wong's bladder. He had bladder cancer. His history of working with plastics at the toy factory may have been a predisposing factor.
Ng performed a minimally invasive procedure on Wong - a transurethral resection of bladder tumour, where the lesions were removed using a cystoscope. Wong suffered minimal discomfort and healed fast. The cancerous tissue showed that Wong had grade-three superficial transitional cell carcinoma - that is, the cells forming the innermost lining of the bladder had become abnormal and multiplied too rapidly. The cell abnormality was considered high, and such cancers can be aggressive.
Another cystoscopy a month later found that the bladder was free of any further sign of cancer, and the operation was considered a success.
However, bladder cancer has a nasty habit of recurring in 50 to 80 per cent of cases. To minimise the risk of recurrence, Ng used a common immunotherapy called intravesical Bacillus Calmette-Guerin (BCG) treatment.
BCG is a vaccine of live, weakened tuberculosis bacteria that stimulates the body to produce cancer-fighting substances, and it is introduced via a catheter into the bladder where the liquid is held for a few hours and then drained.
Wong was to receive weekly BCG treatment for six weeks, followed by a monthly dose for 10 months thereafter - a well-established regimen that's been in use for more than 20 years. For the first six weeks, Wong suffered only a mild, common side effect - slight irritation of the urethra and bladder that caused him to urinate more frequently.
Then Wong started to experience difficulty passing urine. He needed to strain more to empty his bladder, and the stream of urine grew increasingly slower.
One day, he was alarmed to find that despite feeling a great urge to urinate, he simply could not pass urine.
In great distress he was rushed to the hospital, where a catheter was inserted into his urethra to drain the urine. Wong had no other complaints or symptoms, but Ng found that his prostate was slightly enlarged.
As the prostate wraps around the urethra, an enlarged prostate could 'squeeze' the urethra and cut off urine flow. Ng put Wong on an alpha-blocker, a medication to relax the muscles in the prostate and bladder neck. Two days later, the catheter was removed and Wong could pass urine normally.
But two days later, a distressed Wong was back at the hospital, unable to urinate. A catheter was used to relieve Wong's discomfort but Ng now planned to remove part of his enlarged prostate. Before the planned procedure, Wong started to complain of growing discomfort and swelling in his perineum - the area between the scrotum and the anus.
A CT scan showed that fluid had built up in the prostate, causing it to swell and enlarge the perineum. Guided by ultrasound, Ng drained the fluid using a special needle and extracted 25 millilitres of pus. Tests showed that the bacteria in the pus were the same strain as the BCG. The tuberculosis bacteria had somehow migrated from Wong's bladder into his prostate and caused a localised infection.
Once the bacteria travel outside of the bladder, the patient risks developing tuberculosis. So Wong was put on a one-year course of a four-drug antibiotic cocktail. He also needed weekly removal of the pus build-up in his prostate.
Eight weeks after the infection was discovered, Wong could finally urinate on his own. Ng stopped BCG treatment but maintained close watch over Wong for any recurrence of the cancer. After two years, Wong remains cancer-free.
This complication arising from BCG treatment is rare: only a few cases have ever been reported, Ng says. Ng says that while the enlarged prostate was caused by a BCG-related infection, the extended period of using a catheter had resulted in pus build-up in the prostate. Because Wong did not exhibit signs of sepsis or infection, it was initially a challenge to pinpoint the cause of his urination problems.