My son was diagnosed with myocarditis and then pericarditis in July this year. He was lethargic for a while before this happened and has had joint pains for as long as I can remember. He had an MRI of the hands and synovitis was seen in his right hand. He has Raynauds phenomenon and inflammation of his rib cage. He went into hospital for abdominal pain and had his appendix out. After the operation he had a blood pressure of 150/100 and a heart rate of 150 and his oxygen was 84%. He was transferred to ICU for two nights. He then went back to the ward and had seizure like symptoms and was not responding even to pain. He ended up back in ICU for another night. He is waiting for neurologists and an EEG. He has seen a rheumatologist and has started on prednisolone which was helping him until this episode in hospital. All his bloods came back negative to ANA and other antibodies. I am so desperate to help him as he is 19 and so depressed with feeling so unwell. Can anyone suggest anything or any avenue that may help. Do bloods have to come back positive to get a diagnosis?