Gastrointestinal ❯ FUO with Abdominal Pain
CT Protocol for FUO with Abdominal Pain
| Problem | FUO ( fever of unknown origin) with Abdominal Pain |
| Protocol | The protocol for an abdomen with pelvis for FUO requires both oral and IV contrast material. We prefer positive oral contrast (500-750cc) given 60-90 prior to the scan with an additional 250 ml at the time of the study. We also use IV contrast but scan in the venous phase at 70 seconds post injection. Variations of scan protocols will include water as oral contrast and occasionally rectal contrast. Delayed scams in the excretory phase (3-4 minutes post injection) may also be helpful when looking for suspected renal inflammatory disease. We routinely generate scans at .75 mm and 3 mm slice thickness at .5 mm and 3mm intervals. |
| Pearls | 1. The FUO study is one of the most challenging as any organ or organ system may be involved. Clinical history can help localize the source of the problem (LLQ vs RLQ or RUQ or LUQ pain) but often does not help 2. when working up an FUO one must consider infectious as well a neoplastic processes 3. common challenges might be distinguishing infarct from infection in the kidneys and spleen 4. we use oral contrast to detect unsuspected gastric pathology as well as involvement of the small bowel and colon 5. patient age will surely help in reaching suspected diagnosis which may be seen in younger patients (i.e. PID, endometriosis) rather than older patient (i.e. increased incidence of malignancy presenting as an FUO). 6. careful review of the vasculature for vasculitis should be done routinely and this will require 3D mapping especially with MIP imaging. 7. review of bone windows especially on the sagittal view is critical to exclude inflammatory changes of the spine or para-spinal regions 8. routine review of MPR images (coronal and sagittal) is critical for evaluation of the abdomen and pelvis. 3D maps with MIP and VRT may also be very valuable. 9. if the clinical concern is a vasculitis then arterial phase imaging will need to be acquired. |