A curious and kaleidoscopic case of hallucinations reported in the latest journal Arquivos de Neuro-Psiquiatria:
A 95-year-old woman, with four years of schooling, had a seven-year history of DI [delusional infestation]. In the beginning, there were itching and prickling sensations on arms and head. Subsequently, she felt small worms, with different shapes and colors, crawling through her skin or swirling around her body.
After two years, she began to see small pumpkins and flowers coming out of her body and lettuce crawling on the table. She complained of water trickling out of walls and forming puddles on the ground. Occasionally, she saw small children walking on the walls and also worms on the floor and walls.
Sometimes, the parasites set fire to small objects. She became upset with her family and physicians who did not believe her.
The belief that you are infested with hallucinatory parasites is more typically called delusional parasitosis but it is usually not linked to the florid circus of hallucinations reported here, which are more typical of Charles Bonnet syndrome.
Link to case report in Arquivos de Neuro-Psiquiatria.
Mind Hacks 
How terrible. My coworker and I thought we had had the same insect bites last week; I would get them in the middle of the night but for the life of me couldn’t find any insects (they turned out to be allergy hives, not bites). But while scouring the wonderful Internet, I actually stumbled on a site for people who were being attacked by “invisible” bugs. These folks were convinced they were being ignored by medical professionals and that it was some almost otherworldly phenomenon. I can see how a condition like this could create that sort of thought process.