Worldwide prevalence of Helicobacter pylori in patients with Mucosa-Associated Lymphoid Tissue (MALT) lymphomas: A systematic review and meta-analysis

Ali Abdelfattah; Mutaz Jamal  Al-Khreisat; Ola Mohammed  Al-Sanabra; Muhammad Farid  Johan; Faezahtul Arbaeyah  Hussain; AbdelRahman M.  Zueter; Omar  Abuyaman; Khaldun  Jacoub; Samya A.  Omoush; Nor Hayati  Ismail; Abdul Aziz Mohamed  Yusoff; Md Asiful  Islam; Alhomidi  Almotiri; Neil P.  Rodrigues

doi:10.23750/abm.2026.17906

Worldwide prevalence of Helicobacter pylori in patients with Mucosa-Associated Lymphoid Tissue (MALT) lymphomas: A systematic review and meta-analysis

Authors

Ali Abdelfattah Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, The Hashemite University, Zarqa, Jordan; European Cancer Stem Cell Research Institute, Cardiff University, School of Biosciences, Cardiff, UK https://orcid.org/0000-0003-0294-0568
Mutaz Jamal Al-Khreisat Department of Medical Laboratory Sciences, Faculty of Allied Medical Sciences, Al-Ahliyya Amman University, Amman, Jordan
Ola Mohammed Al-Sanabra Department of Medical Laboratory Sciences, Faculty of Science, Al-Balqa Applied University, Al-Salt, Jordan
Muhammad Farid Johan Department of Hematology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
Faezahtul Arbaeyah Hussain Department of Pathology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
AbdelRahman M. Zueter Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, The Hashemite University, Zarqa, Jordan
Omar Abuyaman Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, The Hashemite University, Zarqa, Jordan
Khaldun Jacoub Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, The Hashemite University, Zarqa, Jordan
Samya A. Omoush Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, The Hashemite University, Zarqa, Jordan
Nor Hayati Ismail Department of Hematology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
Abdul Aziz Mohamed Yusoff Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
Md Asiful Islam Department of Biomedical Science and Physiology, School of Life Sciences, Faculty of Science and Engineering, University of Wolverhampton, Wolverhampton, United Kingdom
Alhomidi Almotiri Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Shaqra University, Shaqra, Saudi Arabia
Neil P. Rodrigues European Cancer Stem Cell Research Institute, Cardiff University, School of Biosciences, Cardiff, UK

Keywords:

Campylobacter pylori, Helicobacter pylori, lymphoma of mucosa associated lymphoid tissue, MALT lymphomas, marginal zone b-cell lymphoma

Abstract

Background/Objective: Chronic inflammation resulting from infections or autoimmune disorders plays a pivotal role in the pathogenesis of mucosa-associated lymphoid tissue (MALT) lymphoma, an extranodal non-Hodgkin lymphoma. Helicobacter pylori (H. pylori) is a major contributor to gastric MALT lymphomas. Eradicating H. pylori can induce regression of these lymphomas. However, the global prevalence of H. pylori among MALT lymphoma patients remains insufficiently studied. The present study aimed to determine this global prevalence, crucial for developing effective treatments and improving outcomes.

Methods: An electronic search of five databases using appropriate keywords was performed, including PubMed, Scopus, Cochrane, ScienceDirect, and Google Scholar. The quality of the involved manuscripts was evaluated utilizing the Joanna Briggs Institute critical appraisal tool. The random-effects model was used to report the results as percentages with a 95% confidence interval (CI). The protocol was registered with PROSPERO (CRD42024541706).

Results: Of the 2524 titles identified, 102 studies met the inclusion criteria. The prevalence of H. pylori in patients with MALT lymphomas was 73.0% (95% CI, 69.0–77.1%, n = 8725). The outcomes of sensitivity analysis were consistent, and 70.6% of studies were deemed high quality. Significant publication bias was found by Egger's test.

Conclusion: H. pylori was found in a significantly high proportion of patients with MALT lymphomas. This study recommends that H. pylori testing and eradication should be considered for prediction, targeted treatment protocols, and assessment of the clinical status of MALT lymphomas.

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