Helicobacter pylori infection and asthma: Is there a direct or an inverse association? A meta-analysis

Table 1 Association between Helicobacter pylori infection and Asthma in paediatric population

Ref.	Method for assessing H. pylori infection	Association	No. of asthmatic/No. of control	Age	Quality
Annagür et al[17]	Serological	Seropositivity was similar in acute exacerbations and stable asthmatics	79/36	5-15	3/5
Zevit et al[18]	13C-urea breath test	Inverse association between H. pylori and pediatric asthma	578/6381	5-18	5/5
Khamechian et al[19]	Biopsy samples	Inverse association between H. pylori and pediatric asthma	36/264	5-18	4/5
Karimi et al[20]	13C-urea breath test	Similar prevalence in cases and controls	98/98	< 18	2/5
den Hollander et al[4]	Serological	Positive association between H. pylori CagA- and pediatric asthma	3062/0	6	3/5

H. pylori: Helicobacter pylori; CagA: Cytotoxin-associated gene A.