The freaky beauty practice has people rest their feet in tubs of lukewarm water while tiny fish called Garra rufa nibble at their toes - exfoliating the skin by sucking off dead cells.
The unidentified patient's nails separated from her first three toes over the six months since she received the spa treatment, in which garrarufa fish, or "doctor fish", nibble off dead skin around the feet.
"I do not recommend fish pedicures for any medical or aesthetic objective", Lipner said.
The fish's voracious feasting is said to help treat conditions such as psoriasis as well as beautify the skin, lending them the nickname of "Doctor Fish". Onychomadesis only temporarily stops nail growth, which usually resumes within 12 weeks, according to a 2017 study of the condition. The woman assumed at first that she had onychomadesis, however, her dermatologist informed her that onychomadesis was not the reason this was happening. "I am not convinced at all that the fishes caused the problem", Dr. Antonella Tosti, the Fredric Brandt Endowed Professor of Dermatology at the University of Miami Miller School of Medicine, told CNN.
However, another expert disagrees, saying the woman's toenails could have fallen off because her toes were overlapping inside her shoes.More news: Largest US business group attacks Trump on tariffs
The popularity of fish pedicures peaked about 10 years ago, but they are still trendy today, the report said.
As for the woman, her nails will likely return, but not for a long time.
"I do not recommend fish pedicures for any medical or aesthetic objective", Lipner said. There other known causes of onychomadesis were ruled out, so it's thought that the fish pedicure is to blame.
In 2011, an investigation by the UK's Fish Health Inspectorate found a bacterial outbreak among thousands of these fish, which had been transported from Indonesia to United Kingdom pedicure spas. And though proponents of fish pedicures have argued they can properly sanitise the fish and tubs between uses, research has shown that disease-causing bacteria can be readily found in both the tubs and fish used in these spas.
At least 10 states in the USA have banned the treatment because of its potential health hazards, the CDC said, though 2011 Health Protection Agency guidelines considered the risk of bacterial infection from fish spas to be "very low" but not completely avoidable.
"We did have some concerns about the welfare of these animals being transported around the world, often by people with limited experience", he said.