Alpha1-antitrypsin deficiency and inflammatory bowel diseases

Mayo Clin Proc. 2000 May;75(5):450-5.


Objective: To evaluate a possible etiologic role of alpha1-antitrypsin deficiency (alpha1AD), most frequently caused by a Z allele mutation, in ulcerative colitis (UC) and Crohn disease (CD).

Patients and methods: This retrospective study included 10 patients diagnosed with and/or treated for inflammatory bowel disease (IBD) between 1976 and 1997 and identified from the Mayo Clinic Medical Index System. All 10 patients had either alpha1AD and CD or alpha1AD and UC. The alpha1-antitrypsin (alpha1AT) types and levels were determined with isoelectric focusing testing. The allele types, representing genotypes, were designated PiZZ (or ZZ) for homozygotes and PiMZ (or MZ) for heterozygotes.

Results: Seven patients had UC: 4 were genotype ZZ and 3 MZ. Four of these 7 patients had emphysema, 2 had asthma, and 1 had chronic bronchitis. Five were cigarette smokers, but only 1 had smoked coincident with activity of her UC. Two of the UC patients never smoked, and 1 of these 2 had asthma. Three of the 10 patients had CD, 2 genotype ZZ and 1 MZ. Two of the 3 patients were long-term cigarette smokers, and both had emphysema. Nine of the 10 patients with UC and alpha1AD required surgery.

Conclusions: The need for surgery in patients with UC and alpha1-AD may point to a unique phenotypic subgroup of patients with alpha1AD and severe UC. Further studies are required to substantiate the etiologic role of alpha1AD in IBD. Our observations, if confirmed by future studies, suggest that in patients with both IBD and chronic obstructive pulmonary disease, alpha1AD testing should be considered.

MeSH terms

  • Adult
  • Colitis, Ulcerative / etiology*
  • Colitis, Ulcerative / genetics
  • Colitis, Ulcerative / surgery
  • Crohn Disease / etiology*
  • Crohn Disease / genetics
  • Female
  • Genetic Predisposition to Disease
  • Humans
  • Isoelectric Focusing
  • Male
  • Middle Aged
  • Phenotype
  • Proctocolectomy, Restorative
  • Smoking
  • alpha 1-Antitrypsin Deficiency / complications*