Her parents decided to take her to the hospital after they noticed the lump had got bigger.
Doctors in Iran discovered that two months earlier, the otherwise healthy young girl was bitten on the head by an insect, leaving a small spot.
Writing in Clinical Case Reports, the experts wrote the lump was “hard”, “shiny” and “painful to the touch”.
Scans revealed that the mass, which had since grown to around the size of a tennis ball, was buried in her frontal lobe, part of the brain responsible for memory and emotions.
The medics diagnosed the girl with a pott’s puffy tumour (PPT) a rare but dangerous complication of sinusitis or a sinus infection.
It happens when infectious fluid builds in the forehead.
The growth can also emerge as a result of head trauma, surgery, cocaine abuse, tooth infection and insect bites.
Left untreated, it can lead to brain swelling diseases like meningitis, encephalitis or a brain infection.
The young girl was given a heavy dose of antibiotics after the lump on her forehead was drained of infection during surgery, which included a craniotomy.
A craniotomy is a surgical operation in which a bone flap is temporarily removed from the skull to access the brain.
Six months after the major operation, the mass had not re-emerged, and the doctors gave the child a clean bill of health.