Children with asthma may not realise they are allergic to peanuts because the symptoms are so similar, a study has suggested.

Scientists who carried out a study in the United States said symptoms such as shortness of breath, wheezing and coughing are seen in both conditions.

They analysed the records of more than 1,500 children from the paediatric respiratory clinic at Mercy Children's Hospital in Toledo, Ohio, and found one in 10 (10%) tested positive to peanut sensitivity.

However, more than half (53%) of these children and their families were not aware and did not suspect there was any sensitivity to peanuts.

They found the prevalence of known peanut allergy was similar across age groups.

Lead author Robert Cohn said: "Many of the respiratory symptoms of peanut allergy can mirror those of an asthma attack, and vice versa. Examples of those symptoms include shortness of breath, wheezing and coughing.

"This study demonstrates children with asthma might benefit from a test for peanut sensitivity, especially when control of wheezing and coughing is difficult to achieve.

"If a physician is having this problem, or if a parent notices it in his or her asthmatic child, they should consider testing, even if they believe their child is not sensitive to peanuts."

He added that further research should be carried out into the connection.

Dr Samantha Walker, director of research and policy at Asthma UK, said: "These findings are difficult to interpret because allergy tests to food are notoriously unreliable and require careful interpretation to confirm a diagnosis of peanut allergy.

"Although asthma affects one in 11 people in the UK, including 1.1 million children, it is a complex condition and years of research underfunding means it remains a relative mystery. Many people have positive allergy tests but can eat peanuts safely - and so it is unsurprising that many people tested for this research did not know they would have a positive test result.

"Children with asthma and food allergy together are at increased risk of a severe asthma attack and so should be monitored carefully to keep their asthma under control."