Recurrent or chronic fever is seen in tuberculosis, SLE, rheumatoid arthritis, Polyarteritis nodosa (PAN) and
other auto immune disorders, UTI
, drug fever, glandular fever, otitis media, IBS, HIV, STDs, endocarditis, parasitic infestations, fungal infections, lymphomas and other cancers etc. If you belong to the fairer sex, then even polycystic ovary, menopause, PID (pelvic inflammatory disease) should be investigated for. Dehydration is a frequent cause of low grade fever with malaise.