Intrafamilial Spread of Helicobacter pylori: A Prospective Study
Using Urea Breath Test
By H. Zhou, K.L. Chan, K.M. Chu, and P.K.H. Tam
Hong Kong, China
Purpose: The mode of Helicobacter pylori spread is not well
defined. Urea breath test (UBT) is an accurate and noninva-
sive method for H pylori detection. This study evaluates the
role of intrafamilial spread of H pylori using UBT.
Methods: The family members of 16 H pylori–positive and 16
negative (control) children confirmed by histology and rapid
urease test were investigated with UBT. A 5% change was
considered positive.
Results: A total of 139 persons (72 in the positive group; 67 in
the control group) were studied. Fifty-eight (81%, 58 of 72)
and 13 (19%, 13 of 67) were found to be positive in the H
pylori–positive and control groups, respectively (P .01).
Among children from 19 positive mothers, the positive rate
was 60% (25 of 42), whereas among children of negative
mothers, the positive rate was 16% (4 of 25; P .01). The
positive rate among children of positive fathers was 66% (23
of 35), whereas that among children of negative fathers was
30% (7 of 23; P .01). When both parents were H pylori–
positive, the children’s positive rate was 83% (19 of 23); when
both parents were negative, the children’s positive rate was
0% (0 of 9; P .01).
Conclusions: There is strong evidence of intrafamilial spread
of H pylori. The positivity of parents with H pylori has an
important bearing on their children’s H pylori status.
J Pediatr Surg 35:1672-1675. Copyright © 2000 by W.B.
Saunders Company.
INDEX WORDS: Helicobacter pylori, childhood dyspepsia,
urea breath test.
H
ELICOBACTER PYLORI causes chronic gastritis
and plays an important role in the pathogenesis of
peptic ulcers in adults and children.
1,2
However, the
mode of transmission and source of infection remain
unknown. It has been suggested that person-to-person
transmission is possible and is likely to occur through
close contact with infected individuals, particularly
within the family.
3-5
Increased rates of infection have
been reported in relatives of infected children and
spouses of duodenal ulcer patients,
6,7
low socioeconomic
groups,
8
and cohabiting children.
9
This suggests that
household overcrowdedness may influence the transmis-
sion of the disease.
The aim of the current prospective study was to assess
the frequency of H pylori infection in Chinese family
members by urea breath test.
MATERIALS AND METHODS
Index Children
Sixteen consecutive children who were referred for endoscopy be-
cause of dyspeptic symptoms and found to have H pylori infection in
their gastric biopsies by rapid urease test and histologic examination
were considered H pylori–positive index children. Their endoscopic
findings were duodenal ulcer, n = 3; erythematous patches, n = 3;
mucosal nodularity, n = 7; no gross pathology, n = 3. Another 16
consecutive children during the same period who had similar dyspeptic
symptoms but on gastric biopsy studies did not show H pylori were
used as control. Their endoscopic findings were no gross pathology,
n = 12; duodenal ulcer, n = 2; erythematous patches, n = 2.
Family Members
A total of 107 cohabiting family members of the 32 children were
investigated to determine the frequency of H pylori infection. Positive
group had 56 family members (mean age, 29.4 years; range, 2.5 to 75
years) and control group consisted of 51 family members (mean age,
29.2 years; range, 5 to 80 years).
Urea Breath Test Method
The index children and family members were assessed for H pylori
infection by
13
C-urea breath test (UBT), which was performed using
50- and 75-mg [
13
C]- urea (Dial3-Helico; Dianatec iso, Montreal,
Quebec) in subjects who weighed up to 15 kg, and those who weighed
greater than 15 kg more, respectively. Fasting individuals were asked to
drink 75 mL of a citric acid solution to avoid premature stomach
emptying. Two baseline breath samples were collected directly into
10-mL vacutainer tubes. The tubes were capped immediately after
breath collection. Two additional samples were collected after exactly
30 minutes.
13
C abundance was determined by isotope ratio mass
spectrometry (AP2003 Analytical Precision, Manchester, UK) on
80-L breath samples (90 nmol CO
2
). Isotope enrichment was
expressed as corrected delta per milliliter ( %) relative to the Pee Dee
belemnite limestone (PDB) international standard.
10
The cutoff point of
5% change was considered H pylori positive.
11
Statistic Analysis
Data were analyzed with unpaired Student’s t test. Values were
considered to be statistically significant if they reached P .05.
From the Divisions of Pediatric Surgery and Upper Gastrointestinal
Surgery, Department of Surgery, The University of Hong Kong Medical
Center, Queen Mary Hospital, Hong Kong, SAR, China.
Presented at the 33rd Annual Meeting of the Pacific Association of
Pediatric Surgeons, Las Vegas, Nevada, May 15-19, 2000.
Address reprint requests to Professor Paul K.H. Tam, Division of
Pediatric Surgery, Department of Surgery, The University of Hong
Kong Medical Center, Queen Mary Hospital, Hong Kong, SAR, China.
Copyright © 2000 by W.B. Saunders Company
0022-3468/00/3511-0035$03.00/0
doi:10.1053/jpsu.2000.18349
1672 Journal of Pediatric Surgery, Vol 35, No 11 (November), 2000: pp 1672-1675