Having a cilia test

Tests for abnormalities of the cilia


Cilia are tiny hair-like structures that line the nasal passages and larger airways. They are so small that they can only be seen under a microscope. They continuously move to sweep mucus along the airways to keep the lungs clean. Rarely, due to an inherited abnormality, they do not work properly which can result in a condition called primary ciliary dyskinesia (PCD). This can lead to repeated lung infections and a wet cough, and if left untreated this may lead to lung damage (bronchiectasis). Children usually have an almost constant runny nose and sinus infections can occur (sinusitis). Recurrent ear infections and ‘glue ear’ are also common and can lead to hearing loss. In half the cases the heart is on the wrong side of the chest (right side rather than left). Further information is available from the PCD family support group
www.pcdsupport.org.uk.


Nasal nitric oxide (NNO)


This is a useful screening test for ciliary abnormalities and can be carried out by most children aged 6-7 years and above. The child sits with a small plastic cone-shaped probe placed up against one nostril to seal it shut. The probe is connected by a thin tube to the NO analyser. The child breathes in and out gently then takes a deep breath and holds it for as long as possible. This is repeated 3 times. A level above 200 ppb is considered normal and then there is usually no need to proceed with nasal ciliary brushings, unless the symptoms are highly suggestive or there is a family history of the condition.

 

Nasal ciliary brushings

 

What is this test?


This is a way of sampling the cilia from the nose to see if they move normally and is the gold standard test for PCD.

 

Before the test


If the child is old enough to perform nasal NO (see above) and the test is normal we would not proceed with ciliary brushings. If the result is abnormal or the child unable to have nasal NO measured, then we do need to perform the brushings.

There is no special preparation, but if the child has a bad cold or a recent infection, we may not be able to get a proper sample, so may postpone the test. We tend to wait 3 weeks or so for the nose cells to recover and may give some antibiotics in the meanwhile.

 

What does the test involve?


If the child is having a bronchoscopy under general anesthesia as part of a series of tests, then the cilia will be sampled at the same time. However the test can also be done in the clinic. The child must sit still, and if small enough can be held on a parent’s lap. A tiny brush is inserted into the nostril to take a sample of the cells lining the nose. This is done once or twice and takes about 3 seconds each time.

 

Are there any risks?


It is uncomfortable and stings, in a similar way to a blood test. It is quick however but many young children cry for a short while. It does not hurt afterwards but sometimes a small amount of blood appears from the nostril.

 

After the test


We may have a result on the same day once the movements of the cilia are analysed under the ‘light’ microscope. Sometimes the result is inconclusive and the cilia are sent for further testing with an electron microscope; that result can then take 4-6 weeks. If the initial result is abnormal, the sample will always go for further analysis. Unfortunately, sometimes insufficient cilia are obtained from the brushings and the test needs to be rearranged.