The incidence of 'true' re-infection with Helicobacter pylori after successful eradication remains uncertain.
Dr Zhang and colleagues from China determined the worldwide rates, risk factors and clinical implications of 'true' re-infection of Helicobacter pylori.
'True' re-infection of Helicobacter pylori is defined as the situation where tests for H pylori infection, which were negative for 12 months after eradication, become positive again at a later stage.
The team identified 36 studies through a literature search to be able to produce annual rates of 'true' re-infection.
|Rates varied from 0% to 23% in adults|
|Alimentary Pharmacology & Therapeutics|
Data from 33 original articles were considered reliable and adequate in the further review.
Generally, the reported rates varied from 0% to 23% in adults, and from 2% to 10% in children.
Most studies from developed countries reported rates of less than 1%, whereas relatively higher rates were reported in most of the developing countries.
The researchers noted that the small sample sizes included in the studies appeared to be associated with increased re-infection rates.
The researchers observed that interfamilial transmission is the major cause of re-infection, although iatrogenic re-infection through contaminated endoscopic equipment has been reported.
Dr Zhang’s team concludes, “Helicobacter pylori re-infection is not a concern in a clinical setting, especially in the developed world.”
“However, caution must be exercised in most developing countries.”