Microbiology Fundamentals 2nd Edition by Jennifer Bunn,Marjorie Kelly Cowan

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C A S E F I LE

A Permanent Fix
When I was an ultrasound technician in an urban hospital, I met Jaelyn, a little girl with vesicoureteral reflux (VUR). Vesicoureteral reflux is a congenital condition of the urinary tract system in which the ureters are attached to the wall of the bladder at an angle that allows urine to "reflux" backward from the bladder to the kidneys. Children with VUR can experience frequent kidney infections, which can damage the kidneys, sometimes permanently.
Many children with moderate VUR require constant antibiotic suppression therapy to prevent episodes of pyelonephritis (kidney infections). These children remain on antibiotics for a few years and will sometimes outgrow the problem as their ureters grow. Jaelyn was no different than most children with moderate VUR-she was on antibiotics continuously from the time she was 7 months old when her condition was discovered. I would see Jaelyn and perform an ultrasound on her kidneys every 6 months to monitor her kidneys-and more often if she developed an infection requiring hospitalization and intravenous antibiotics.
In addition to kidney infections, Jaelyn was a sickly child who seemed to catch every bug that went around. She had constant colds, ear infections, and gastrointestinal viruses, possibly because her immune system was constantly working to fight off urinary tract infections. The fact that she was constantly taking antibiotics might have also contributed to her frequent infections.
When Jaelyn was 3 years old, she was hospitalized with her fifth kidney infection. I was called to perform another ultrasound. On ultrasound, her kidneys appeared dilated, and cultures of her urine came back showing Pseudomonas aeruginosa, a gram-negative bacterium that is an opportunistic pathogen.
The discovery of P. aeruginosa in Jaelyn's urine led to the decision to perform surgery to correct the angle of Jaelyn's ureters so that urine could no longer reflux into the kidneys. Following surgery, Jaelyn continued to take suppressive antibiotic therapy for 1 month, after which she was able to stop taking antibiotics. I saw Jaelyn once more after her surgery to recheck her kidneys. At her last ultrasound appointment, Jaelyn's kidneys were normal size and functioning well.
• What is an opportunistic pathogen?
• Why did the discovery of P. aeruginosa in Jaelyn's urine lead to the decision to perform surgery?