Upper Gastrointestinal Bleeding Following Legionnaires' Disease Case Report

Abstract

Background: Legionnaires’ disease can involve multiple systems of the human body. However, in the majority of cases, it presents as a pneumonic illness responsible for 2–15% of community-acquired pneumonia cases that necessitate hospitalization. Herein described is a case of a 51-year-old male presenting with productive cough and headache who was later diagnosed with legionella pneumonia. He suffered from several episodes of gastrointestinal bleeding subsequently. To the best of our knowledge, prior to this case, only sixteen cases of gastrointestinal bleeding following Legionnaires’ disease have been reported. Methods: Approval was obtained from the Institutional Review Board of Kern Medical. A retrospective review of the patient’s record was performed. The literature search was conducted on PubMed and Google Scholar. These search terms were applied: Legionnaires’ disease, Legionnaires’ disease complication, gastrointestinal bleeding following Legionnaires’ disease, legionella pneumonia.Results: GI bleeding is rare in LD and the relationship between this association is uncertain. Legionella pneumophila is equipped with Dot/Icm Type IV Secretion System (T4SS), which is a cable to deliver up to 300 effector proteins into the cytoplasm of the host cells. These proteins function as virulence factors. It is worth mentioning that Helicobacter pylori (H. pylori) a known GI pathogen is also armed with a T4SS like Legionella pneumophila called H. pylori Cag T4SS.Conclusion: Further studies are needed to prove the relationship, but clinicians should search for the presence of this pathogen in other organs to understand the pathophysiology of extrapulmonary diseases. We must learn to cast a finer net when fishing for the cause of the symptoms. The etiology may be passing right through our screening methods