We describe herein the case of a 48-year-old man who underwent emergency ma
ssive resection of the small intestine due to strangulated ileus, which led
to short bowel syndrome (SBS) as he was left with 7 cm of jejunum and 8 cm
of ileum. We evaluated the immune function in this patient, focusing parti
cular attention on T-cell-mediated immunity. Biochemical and nutritional pa
rameters, including minerals and trace elements, indicated that the patient
was in relatively good health; however, the proliferative response to mito
gen and tumor necrosis factor-alpha production in response to the anti-CDS
monoclonal antibody in peripheral blood lymphocytes (PBL) were impaired com
pared with age-matched postgastrectomy patients and healthy donors. Moreove
r, the expression of T-cell receptor (TCR) zeta, which is involved in signa
l transduction and the subsequent activation of T cells, was downregulated
in this patient compared with that in the age-matched postgastrectomy patie
nts and healthy donors. These observations suggest that T-cell function was
disturbed in our patient, and that this dysfunction was associated with th
e decreased expression of TCR zeta molecules.