Took my otherwise healthy 6.1, slender, athletic, 16 year old son to the ER with abdominal pain which came on gradually then moderate to severe within about an hour. He started to throw up when we go to the ER and became pale. A type of Cat scan through the rectum showed enlarged lymph nodes and his blood work showed a high lymphocyte count, along with cloudy urine. His temperature stayed a little over 98 degrees and no diarrhea. The doctor sent him home with pain and nausea medication and said return if he spikes a fever and /or pain gets worse. He is still tender to the touch and sleeping most the day, normally very active doing card type workouts. He is tall and slender, with not much body fat, and the doctor said it is makes the test procedure more uncomfortable and difficult to be too conclusive counting out an appendicitis. Could this be just a virus since the pain is more uncomfortable and tender to the touch below his belly button and to his right? Wouldn't a virus cause a fever?