Hi, thanks for your question. Please rate my answer if you are satisfied. Well, 102 degrees is a high temperature. Fever this high is usually caused by an infection. If your friend was discharged and is still having high grade fever that means the infection is still there. About the blood tests, there are a few things that will go high generally in the blood when there is an infection in the body (like TLC, Neutrophils or Lymphocytes). Other than that everything will stay usually normal. So blood tests usually don t tell much about infections they just give a clue that you may have one. There are tens of other places you have to look for to reach an infection (like stool, urine, CSF, chest X-ray, abdominal ultrasound, even MRI brain). I m not suggesting your friend to get these tests, I m saying that only to make you understand. But your friend really needs to see a physician to reach the diagnosis. It s also possible that your friend is already on the right treatment because antibiotics can take a couple of days to show response.