HI, thanks for using healthcare magic
The halo test is based on the fact that CSF will separate from blood when applied to an absorbant surface. It is a useful test but not completely accurate.
It is possible that the brown discharge is related to blood in the sinus passages.The blood can occur due to inflammation of the sinuses
.This would be treated with antihistamines, nasal sprays and possibly antibiotics.
IN the absence of head trauma
, it is unlikely that there is leakage of CSF.
I hope this helps