<s>[INST] my 20 ear old son went to the ER with rlq pain.Cat scan said 8 mm right UPJ calculus without hydronephrosis.They sent him home with diagnosis abdominal pain andi don t think they saw this, he is still having intermittent rlq burning cramping pain. could you explain what you think? [/INST] i think that the calculus is still there and he is trying to eliminate it. take ketorolac+buscopan injection in muscle for pain, drink at least 2lt water a day and go again to the ER showing the CT results. do a US scan to see if hydroureteronephrosis is now present. ask for lythotripsy. if he doesn't eliminate the calculus risks kidney loss and infection </s>