Mucosa-Associated Lymphoid Tissue Lymphoma of the Stomach Associated with a <i>Helicobacter heilmannii</i> sensu stricto Infection One Year After the Successful Eradication of <i>Helicobacter pylori</i>

Gastric infection by non-Helicobacter pylori Helicobacter (NHPH) species causes gastric disorders, including mucosa-associated lymphoid tissue (MALT) lymphoma. We herein report a dog lover with MALT lymphoma associated with a H. heilmannii sensu stricto infection. H. heilmannii s.s.-associated MALT lymphoma was detected one year after the eradication of H. pylori against lymphoid aggregates. Given that NHPH species colonize the stomachs of cats and dogs, gastric colonization by H. heilmannii s.s. might be involved in the development of MALT lymphoma in this dog lover. Therefore, it is crucial to consider the possibility of gastric infection with NHPH species in cat or dog lovers.