A few weeks ago on the show “Grey’s Anatomy”, a patient was admitted with extremely swollen testicles and an inability to urinate. The man had recently been on a trip to South America and had been swimming in the Amazon River. He admitted in a subtle manner that he may have had sex while in the area and was afraid he might have contracted some sort of sexually transmitted disease. Many tests were performed to determine the cause of his painful condition, but an Xray discovered a small skeleton shaped like a fish in his urethra. “I don’t believe it – it’s a penis fish!” shouted one of the interns.
The man on the program had a parasite called the candiru or “toothpick fish”, one of the tiniest vertebrates on the planet. It is a small catfish that swims around at the bottom of the river stalking its prey (other fish). Humans are not usually hosts. The candiru can taste traces of urea and ammonia that are expelled from the gills of its prey.
As it turned out in the the show, the man had not only been swimming in the Amazon, he had also peed in the water. Guess what – urine is composed largely of urea and ammonia. The urine attracted the candiru and it swam to the source (his penis) and entered his urinary system, making its way to the bladder. It is a carnivorous fish so it eats its way up, gets bloated, and can’t be pulled out. It also has backwards-facing barbs that prevent the host from pulling it out without significant pain and damage to the host.
So was this story merely a fabrication for a medical show plot. No!
Check this out for more info: damninteresting.com
The moral of the story: do not pee while swimming in the Amazon.
photo credit damninteresting.com