Pediatric Helicobacter Pylori Infection Clinical Presentation
- Author: Mutaz I Sultan, MBChB, MD; Chief Editor: Carmen Cuffari, MD more...
When obtaining the history of patients with Helicobacter pylori infection, one should pay particular attention to anorexia and weight loss, pallor or laboratory findings of anemia, vomiting, abdominal pain associated with meals or nighttime, and any description of GI bleeding. A history of such findings raises the concern of peptic ulcer disease (PUD).
In the child in whom H pylori infection is suspected, the history should include the following:
- Character, location, frequency, duration, severity, and exacerbating and alleviating factors of abdominal pain
- Bowel habits and description of stool
- Appetite, diet, and weight changes
- Halitosis, vomiting, and description of gastric material
- Family history of ulcer disease or GI conditions (eg, Crohn disease)
- Medications (prescribed and over the counter)
- Previous diagnostic testing and specific therapy in the GI tract
Physical examination of an asymptomatic child with H pylori infection usually yields unremarkable findings. In the child with chronic gastritis, duodenitis, and PUD, important examination findings include epigastric tenderness or findings consistent with GI bleeding (eg, guaiac-positive stools, tachycardia, pallor).
Children with PUD leading to complications (eg, severe blood loss in the GI tract, perforation, obstruction) can appear ill and have evidence of hemodynamic instability or signs of an acute abdomen. Children with long-standing PUD from H pylori may become profoundly anemic from undetected chronic bleeding and have no complaints.
- Assess the general appearance of the child.
- Assess perfusion, with attention to mental status, heart rate, pulses, and capillary refill.
- Assess the skin and conjunctivae for pallor.
- Perform a thorough heart and lung examination.
- Inspect, auscultate, and palpate the abdomen.
- Perform rectal examination and a stool guaiac test.
Epidemiologic studies have addressed various factors, such as bacterial, host, genetic, and environmental factors, to determine the causative links to H pylori infection. Data support person-to-person spread of infection, possibly related to dental plaque, but knowledge of reservoirs and transmission modes is incomplete.
Causes of H pylori infection include the following:
- Person-to-person transmission of H pylori infection is noted.
- Infection clusters are noted, particularly in families with infected children. The possible routes are fecal-oral, oral-oral and gastro-oral. Mother-to-child transmission was strongly suggested in a study of DNA analysis of the H pylori strains. The data showed identical H pylori strains between mothers and their toddler-aged children. Moreover, the mother’s symptoms of nausea and vomiting and the use of pacifier were significantly associated with the risk of H pylori infection in children.
- In a very interesting longitudinal study from the US-Mexican border, Cervantes et al showed that a younger sibling was 4 times more likely to become infected with H pylori if the mother was infected with H pylori compared with an uninfected mother. Younger siblings were 8 times more likely to become infected if their older index sibling had persistent H pylori infection.
- The possibility of H pylori transmission among children in daycare centers or kindergarten, where interpersonal contacts are common, was also proposed. A meta-analysis of 16 studies did not confirm this hypothesis. The summary OR was 1.12 (95% confidence interval, 0.82–1.52). However, the authors highlighted the limitations of the published studies, including different types of childcare, different age groups, and lack of differences in the exposure duration, with exposure giving a high heterogeneity to the meta-analysis results.
- Crowding and poor personal hygiene may also play a role.
- An increased prevalence of H pylori infection is noted in developing countries. This may reflect the combined effects of poor living conditions, poor hygiene, and crowding.
- In the United States, socioeconomic level is strongly and inversely related to the prevalence of H pylori infection, a finding that may also reflect the same factors as those noted in developing countries.
- Bacterial factors may play a role in the clinical manifestations of H pylori infection.
- Patients with H pylori infection have 2 basic phenotypes based on the presence or absence of a vacuolating cytotoxin.
- People with cytotoxin-positive infection have endoscopically proven inflammation that is more pronounced than those of patients with cytotoxin-negative H pylori infection.
- Host factors may play a role in the acquisition of H pylori infection.
- Children may be better able to clear acute infection than adults (2% per year).
- Hypochlorhydria may be necessary to allow H pylori to colonize in the stomach.
- Normal gastric epithelial cells that line the stomach are necessary for H pylori persistence. H pylori is not found in atrophied metaplastic epithelium.
- Data from only one study links an increased prevalence of H pylori infection with a community's water supply.
- Other possible ways of transmission include vector-borne transmission.
- H pylori isolates are found more often in personnel who work in the endoscopy suite than in the general population.
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