Pyridoxal-5'-phosphate deficiency after intestinal and multivisceral transplantation

Successful intestinal transplantation is measured by the achievement of clinical nutritional autonomy (CNA). However, the ability of the graft to maintain normal micronutrient levels including vitamins has yet to be thoroughly evaluated.

After an initial clinical observation of isolated cases of pyridoxal-5'-phosphate (PLP) deficiency, this prospective study was designed to address the incidence of, risk factors for, and management of PLP deficiency in adult intestinal transplant recipients.

Serum PLP and homocysteine concentrations were prospectively measured before and after transplantation at frequent intervals.

PLP deficiency occurred in 10% of candidates and in 96% of recipients within a median onset of 30 d (range: 4-118 d) after transplantation. Of this group, 41% were receiving parenteral nutrition (PN), 41% were receiving enteral feeding, and the remaining 18% had already achieved CNA. The overall cumulative risk was 24% at 15 d, 59% at 30 d, 79% at 45 d, and 90% at 90 d; none of the risk factors, including homocysteine concentrations, were significant. Nonetheless, the development of PLP deficiency during PN therapy was associated with a significant (P < 0.001) delay in the achievement of CNA. Despite development of severe deficiency in most cases, none of the subjects experienced clinical manifestations of PLP deficiency because of prompt replacement therapy.

Serial monitoring of serum PLP concentrations is recommended for PN-dependent patients with short-bowel syndrome before and after transplantation for early detection and prompt initiation of preemptive therapy. Long-term measurement at frequent intervals is also recommended, particularly for transplant recipients, to diagnose late deficiency despite achievement of CNA and to prevent toxicity from overdose.