Primary Ciliary Dyskinesia Flashcards
What is primary ciliary dyskinesia (PCD)?
Primary ciliary dyskinesia (PCD) is also known as Kartagner’s syndrome. It is an autosomal recessive condition affecting the cilia of various cells in the body. It is more common in populations where there is consanguinity, meaning the parents are related to each-other. Consanguinity increases the risk of a child having two copies of the same recessive genetic mutation.
What is the inheritance pattern of PCD?
It is an autosomal recessive condition.
Briefly describe the pathophysiology of PCD
PCD causes dysfunction of the motile cilia around the body, most notably in the respiratory tract. This leads to a buildup of mucus in the lungs, providing a great site for infection that is not easily cleared. This leads to a similar respiratory presentation to cystic fibrosis, with frequent and chronic chest infections, poor growth and bronchiectasis.
How does PCD affect fertility?
It also affects the cilia in the fallopian tubes of women and the tails (flagella) of the sperm in men, leading to reduced or absent fertility.
What does PCD have a strong link to?
There is a strong link between primary ciliary dyskinesia and situs inversus.
What is Kartagner’s triad?
Kartagner’s triad describes the three key features of PCD. Not all patients will have all three features. These are:
- Paranasal sinusitis
- Bronchiectasis
- Situs Inversus
Briefly describe situs inversus
Situs inversus is a condition where all the internal (visceral) organs are mirrored inside the body. Therefore the heart is on the right, the stomach is on the right and the liver is on the left. Dextrocardia is when only the heart is reversed.
25% of patients with situs inversus will have primary ciliary dyskinesia. 50% of patients with primary ciliary dyskinesia have situs inversus.
Situs inversus on its own does not cause any problems, and patients can expect to live a normal life. A small number have associated congenital heart disease, such as transposition of the great arteries.
Briefly describe the diagnosis of PCD
Patients typically present with recurrent respiratory tract infections. Take a careful family history and a history of consanguinity in the parents. Examination and imaging (e.g. chest xray) can be used to diagnose situs inversus. Semen analysis can be used to investigate for male infertility.
The key investigation for establishing the diagnosis is to take a sample of the ciliated epithelium of the upper airway and examine the action of the cilia. A sample can be obtained through nasal brushing or bronchoscopy. Often several samples are required.
Briefly describe the management of PCD
Management is similar to cystic fibrosis and bronchiectasis with daily physiotherapy, a high calorie diet and antibiotics.
