I have folliculitis and needle biopsies came back negative can i have an incisional or punch biopsy to isolate the microbe?

Sometimes: Folliculitis is usually staph aureus. If you have recurrent painful boils and drainage, that is culture negative, your problem may be hidradenitis and not folliculitis.

More info needed: Good question. A needle aspirate seems rather difficult to get a good sample for micro. Hopefully, less invasive ways were considered, such as empiric antibiotics for a simple folliculitis. In other situation, a non-bacterial cause could explain the folliculitis- in fact, certain drugs can cause a drug reaction in the form of a folliculitis. Otherwise, a punch biopsy is the next step.