I have a case study for a person who has aids, hepatitis, and tb, but his WBC count is normal. What is the clinical significance of the normal wbc?

None whatsoever. The white count is the sum of the absolute granulocyte, absolute lymphocyte, and absolute monocyte counts. Anyone can have tb, and hepatitis isn't an hiv-related illness except from similar risks. An aids (cd4 lymphocytes below 400 maybe) patient can (and usually does) have granulocytes at the high end of normal and thus a WBC count in normal range.