After complaining to doctors about pain and difficulty passing urine over three days, a bladder stone just about the size of an ostrich egg was discovered inside a 64-year old patient.
The New England Journal of Medicine documented the discovery of the object weighing in at 770g.
The patient did not have a normal bladder, however. Over a decade earlier the patient had invasive bladder cancer that required his bladder to be removed.
His doctors subsequently constructed a bladder out of some intestinal tissue, called a neobladder.
After doctors physically examined the patient, they performed a scan which confirmed the presence of a stone.
Image: The New England Journal of Medicine ©2017
Although the bladder stone is on the large side, it is actually not the biggest recorded bladder stone removed from an individual.
Doctors removed a stone weighing in at around 1.9 kg from a Brazilian man in 2003, according to the Guinness World Records.
Bladder stones normally aren't more than a few centimetres in size.
Stones are formed by the crystalisation of salt in the urine. A stone found in the bladder may cause mild discomfort in the lower abdonimal region but may not always be detected without a medical examination as it does not usually cause any symptoms.
Further possible symptoms include nausea and vomiting, abdominal distention, chills, fever, and blood in the urine.
If the stone is large enough to block the flow of urine, bacteria become trapped in the urine, leading to a urinary tract infection (UTI). When stones block the urinary tract for a long time, urine backs up in the tubes inside the kidney, producing pressure that can distend the kidney and eventually cause damage.
The combination of obstruction and infection is regarded as an emergency because stones can cause permanent damage in the kidney within 24 to 36 hours.