Slaughter pigs are commonly infected by closely related but distinct gastric ulcerative lesion-inducing gastrospirilla

An association between (unculturable) gastrospirillum-like organisms (GLO) and ulcerative lesions in the pars oesophagea in stomachs of swine has been claimed. In dogs GLO detected by microscopy may represent several Helicoba cter species or subspecies, Therefore we investigated which Helicobacter sp p, are present in stomachs of swine and their possible association with ulc erative lesions of the pars oesophagea, The presence of Helicobacter spp. i n the antrum and pars oesophagea in 122 stomachs of slaughter swine was det ermined by microscopy (n = 122), by culture on selective and nonselective m edia (n = 112), and by a genus-specific 16S ribosomal DNA (rDNA) PCR (n = 8 0). GLO could not be cultured. Phylogenetic analysis of 43 16S rDNA fragmen ts (out of 54 PCR-positive biopsy specimens) revealed the presence of Helic obacter heilmannii type 1 in 42 of them. This correlated with the presence of bacteria with GLO morphology. Helicobacter bills 16S rDNA was amplified directly from one sample harboring bacteria with H. bilis morphology. The a ssociation between Helicobacter spp. and gastric lesions was investigated w ith a second group of 41 pigs with (n = 21 cases) or without (n = 20 contro ls) gastric lesions. Fifteen of the 21 cases were positive by PCR or micros copy, compared to 7 of 20 of the controls (P = 0.03). 16S rDNA sequence ana lysis of 7 of 14 PCR-positive cases revealed the presence of H. heilmannii type 1, Microscopy showed bacteria with CLO morphology. One sample (cases) was culture negative but PCR positive for Helicobacter pullorum-related 16S rDNA. In conclusion, our findings indicate that H. heilmannii type 1 is th e predominant Helicobacter spp. in the stomachs of pigs and that its presen ce is associated with ulcerative lesions in the pars oesophagea.