Purpose: This study was designed to investigate the development of anemia during functional ileoanal pouch.
Methods: Eighty-three patients received an ileoanal pouch between 1980 and 1987. The hematology data deviations among the preoperative period, defunctionalized stage, and after ileal pouch in function were monitored. Aspects studied included serum hemoglobin, iron, folates, vitamin B12, white blood cell, erythrocyte sedimentation rate, pt-B12, and fat absorption. Specimens were collected before colectomy, during ileostomy prior to pouch operation, before loop ileostomy closure, and at 6, 12, 18, 24, and 36 months after loop ileostomy closure.
Results: Two patients developed iron deficiency anemia after 2.5 and 5 years of pouch function: one patient, a vegetarian, had low hemoglobin, iron, and vitamin B12 postoperatively, the other patient developed low iron and hemoglobin 5 years after the operation. Significant elevations of serum hemoglobin, iron, and folates were seen preoperatively vs. postoperatively from 123.46 +/- 2.845 g/l, 10.282 +/- 0.992 mumol/l, and 9.983 +/- 1.308 mmol/l to 138.842 +/- 1.563 g/l (P < 0.0001), 17.544 +/- 1.529 mumol/l (P < 0.0003), and 16.784 +/- 1.757 mmol/l (P < 0.01) (mean +/- SE) of the defunctionalized loop ileostomy. Serum B12 decreased insignificantly. After loop ileostomy closure, at 6 and 36 months of functional ileal pouch-anal anastomosis, the elevations were still significant; serum hemoglobin was P < 0.0001 and P < 0.01, and serum iron was P < 0.001 and P < 0.01, respectively. Vitamin B12 levels decreased insignificantly at six months in controls and significantly (P < 0.01) at 36 months. There was a significant increase of serum folates (P < 0.01 and P < 0.001). Patients with low iron were 50 percent at precolectomy, 23 percent with ileostomy, 16 percent with loop ileostomy, 15 percent at six-month follow-up, and 11 percent at 12-month follow-up. Although only 3 percent and 11 percent of the patients with ileal pouch-anal anastomosis had low serum vitamin B12 values at the 12-month and 36-month follow-up, 31 percent and 36 percent had decreased Schilling tests. Thirty-three percent and 41 percent had decreased 14C-triolein breath tests. In five patients vitamin B12 deficiency began during the first six months of pouch function: in two patients after one year and in one patient after two years. Eight of 83 patients have had substitution therapy with vitamin B12. The therapy was discontinued in three patients after two to four years; these patients developed no further symptoms and had normal Schilling tests in the succeeding 30 months to 46 months. Five patients continue with substitution after 40 months to 68 months. During the functional period, serum erythrocyte sedimentation rate and white blood cells were elevated in some controls on different occasions. Folates were normal throughout the functional period.
Conclusion: For predicting hematologic data outcome in patients with functional ileal reservoir, the results justify the necessity for control during both manipulative and functional periods until evaluations are reliable and satisfying.