Hi and thanks for your query,
The 2 x rays being normal eliminate almost completely the possibility of a
respiratory tract infection or
pneumonia. tenderness to touch is however suggestive of an inflammatory origin.
Treitz syndrome would have been very likely if the pain was so intense at the junction between the
sternum and the ribs.
Measuring markers of inflammation in this case could make things clearer. Increased ESR and CrP levels shall be in favour of an acute inflammatory state. I suggest these markers of inflammation should be run, and if positive,
corticosteroids and analgesics could be appropriate for the start.
Thanks and hope this helps, Making an appointment with an internist could help.
best regards,
Luchuo, MD.