Abstract:
ABSTRACT
Background: H. pylori is a bacterium which affects the majority of population worldwide,
and accounts for more than 50% of the population. The H. pylori infection is common in
developing countries like Tanzania where more than 50% of the population are infected.
H. pylori infection is a communicable disease which is transmitted through the faecal-oral
route in contaminated water and food. It is associated with acute, chronic and atrophic
gastritis, peptic ulcers and malignancies such as adenocarcinoma and mucosal associated
lymphoid tissue lymphoma. The cost of management of patients to the country is high and
may result into a vicious cycle of poverty. Immunohistochemistry is one of the superior
methods and is regarded as a gold standard for detection of H. pylori, hence it will help in
the establishment of the relationship between the bacteria and the associated lesions as it
has been reported in this study. Despite its worldwide distribution, few studies have been
done in Tanzania to detect the H. pylori in gastric biopsies in relation to the gastric
pathologies it causes.
Objective: To determine the pattern of H. pylori associated gastric lesions at MNH using
immunohistochemistry.
Methodology: A descriptive cross-sectional study, retrospective laboratory based study
was conducted at Muhimbili National Hospital Histopathology Laboratory in which 50320
specimens were retrieved and 743 were gastric specimens. 170 FFPE blocks and slides
were retrieved from the archive of the year 2012- 2016, and were then stained with
Hematoxylin and Eosin. All cases were immunohistochemically stained using a polyclonal
antibody (DAKO) to detect H.pylori antigens and reviewed by two senior surgical
pathologists (supervisors). The protocols for the procedures were adopted from MNH
SOPs.
Results: 170 gastric biopsies were identified (patient mean age 50, 109 males, 61 females).
Morphologies included 61% (103/170) inflammatory lesions, 4% (7/170) benign neoplastic lesions and 35% (65/170) malignant lesions. H. pylori was detected in 11.2% of
cases (19/170) by H&E and 37% (63/170) by immunohistochemistry, and was most
frequently seen in cases with chronic inflammation 55.6% (35).
vii
Conclusion: H. pylori is a common bacterial infection most frequently associated with
chronic inflammation and was identified at a prevalence lower than described in the
literature. Immunohistochemistry was more sensitive than H&E alone in identifying H.
pylori. Additional studies are needed to determine the prevalence in the general population.
