A man turned up to A&E terrified at his hands turning blue before medics discovered the simple and hilarious explanation.
The patient had gone to an A&E department in Paraguay saying he thought he was watching himself slowly die as the colour drained from his extremities.
Baffled doctors ran a number of tests, reported local media, worrying he could be suffering from a dangerous cardiac condition.
Doctor Ale Ginzo took to Twitter to explain how the young patient's case at first stumped the entire department.
He wrote: "Young patient without any underlying disease comes in for bluish discolouration of the hands.
"Vital signs are checked, heartbeats are listened to, rheumatological history is sought. Everything normal."
Dr Ginzo said they were concerned because the man's puzzling blue hands might have been caused by acrocyanosis, a viral disease, or thrombosis.
Acrocyanosis is a blueness of the extremities caused by pulmonary and cardiac conditions or local tissue oxygenation defect.
The possible viral disease, he said, may have affected his extremities.
The possible thrombosis, on the other hand, may have been caused by hyperprothrombinemia due to recurring viruses.
Hyperprothrombinemia is a rare blood disorder that results in an impaired blood clotting reaction.
Dr Ginzo continued: "Colouration did not improve despite having stable vital signs and no other ailments.
"But how was this enigmatic case solved? What was the diagnosis?"
The successful diagnosis, however, was an act of pure jean-ius.
Dr Ginzo said: "Patient refers to having bought new jeans and constantly using alcohol spray.
"He cleaned his hands with the alcohol and rested them on the new jeans. Result: blue hands.
"Treatment: clean your hands before going to the emergency room."
Twitter user Lalo Vargas replied: "Something similar happened to me, one day my face was all yellow, I went to the doctor, the doctor made me wash my face.
"I was a teacher at a university, I used the blackboard, that day I used yellow chalk, I stood there like a true clown."
