Magen-Darm- und Verdauungssystem

Abstrakt

Effect of Percutaneous Endoscopic Gastrostomy Tube Placement on the Outcome of the Fecal Occult Blood Test

Pragnesh Patel, Robert Yeh, Rasna Gupta, Colette Renaud Maher, Jamil Akhras and Martin Tobi

Background: Patients undergoing percutaneous, endoscopic gastrostomy tube placement represent a population of patients with a background of serious disease, many at risk from gastrointestinal hemorrhage. It is common practice to monitor stool for GI blood loss using the FOBT. It is unknown whether the presence of a gastrostomy tube will render the FOBT positive. We evaluated a population for the effect of tube placement on FOBT outcome.
Methods: 67 consecutive patients undergoing tube placement were selected on basis of a FOBT having been performed before and/or after the procedure and divided in to two groups. In group one, 31 patients had a test before and 10 patients had test after tube placement with 7.3% having positive FOBT before or after placement. In group two, 26 patients were tested both before and after the procedure with 12% having positive FOBT after tube placement. Indications for tube placement were for neurological disease, dysphasia and nutritional support. Indications for performing the FOBT after tube placement were suspicion or confirmation of GI bleeding in 13 patients. Non-steroidal anti-inflammatory medications were taken by 47% of patients. The mean time of pre-procedure FOBT was 9.3 ± 10 months and of post-procedure testing was 4.4 ± 6.0 months.
Results: 7.3% patients of group1 were FOBT positive before or after tube placement, as opposed 12% of group 2 were FOBT positive after placement (p>0.05). In group two, 3% remained positive before and after the test, 7.5% reverted to negative after having positive FOBT prior to tube placement, and 16.4% were negative before and after tube placement. Survival in months tended to be less in subgroup of patients who had positive FOBT after tube placement (8.87 ± 8.59 months) compared to patients who had positive FOBT prior to tube placement and negative FOBT respectively (24.00 ± 24.00 months and 18.67 ± 25.78 months; p = 0.15 and p = 0.09 respectively).
Conclusion: The tube placement does not appear to affect the outcome of FOBT positive status whether measured cross-sectionally by overall prevalence or longitudinally by status change after tube placement. Although survival in months was not statistically significant between the two groups, there was a strong trend towards reduced survival rate in the group with positive FOBT after tube placement. Thus, presence of a tube is an unlikely explanation for a positive F0BT and other causes may need to be considered. Future larger prospective studies are needed to assess the implication of positive FOBT with regard to survival in patients with a gastrostomy tube.