What are the other Names for this Condition? (Also known as/Synonyms)

• Immotile Cilia Syndrome (ICS)
• Kartagener Syndrome
• Polynesian Bronchiectasis

What is Primary Ciliary Dyskinesia? (Definition/Background Information)

• Primary Ciliary Dyskinesia (PCD) is an uncommon genetic disorder that causes abnormalities involving the cilia, which are present inside the airways. The cilia are tiny hair-like structures that help in signal transmission and movement of mucus
• Cilia are present in various parts of the bodies. In the airways, the movement of cilia helps in coughing out small inhaled foreign bodies (such as dust particles) with the help of mucus. Such cilia are present in the bronchial airways and trachea (windpipe). Cilia present in other parts of the body have a variety of different physiological functions, depending on their locations
• Primary Ciliary Dyskinesia is generally inherited in an autosomal recessive manner; while, in many, the exact cause of PCD development is unknown. Researchers have identified several genes that are responsible for the condition
• Abnormalities in the cilia cause it to become dysfunctional (i.e., either immotile or dysmotile) or defective. Due to this, the airway passages accumulate fluids, since the cilia are unable to clear them from the lungs and sinus cavities. This results in infection and other complications
• Primary Ciliary Dyskinesia can result in chronic sinus infections, hearing loss, severe breathing problems in infants, and recurrent lung infections in many affected individuals. Complications may also include infertility, abnormalities of organ arrangement within the body (situs inversus), and lung failure
• The treatment of Primary Ciliary Dyskinesia may involve exercises and physical therapy to dislodge mucus from the chest (in order to expel it from the body through coughing), administration of medications, and surgery, if needed
• The prognosis of the condition is based upon the severity of the symptoms, complications observed, and the response to treatment. In many cases, prompt diagnosis and appropriate treatment may help improve the quality of life of individuals with Primary Ciliary Dyskinesia

Who gets Primary Ciliary Dyskinesia? (Age and Sex Distribution)

• Primary Ciliary Dyskinesia is a rare congenital disorder with a prevalence rate of about 1 in 10,000 births
• The presentation of symptoms may occur at birth, or sometimes develop into adulthood
• Both males and females may be affected
• Worldwide, individuals of all racial and ethnic groups may be affected

What are the Risk Factors for Primary Ciliary Dyskinesia? (Predisposing Factors)

• A positive family history may be an important risk factor, since Primary Ciliary Dyskinesia is an inherited disorder
• Currently, no other risk factors have been clearly identified for PCD

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Primary Ciliary Dyskinesia? (Etiology)

Primary Ciliary Dyskinesia is caused by mutations in several genes that may be inherited from the parents. Research scientists have identified about nine genes that may be involved in the development of the condition.

• Among these, mutations on two specific genes, namely the DNAI1 and DNAH5 genes, are observed to be responsible for nearly 40% of the cases. Such genetic abnormalities affect the functioning of specific proteins that are responsible for the growth and normal function of the cilia
• The cilia are extracellular hair-like structures that play an important role in receiving and transmitting cellular signals, as well as in back and forth (bending) movement. Impairment in either the functional ability or quality of cilia severely affects the normal function of the tissues and organs in many parts of the body
• Especially within the nasal passages, airways, and lungs, the mucus at the back of the throat and in the airways laden with dust, dirt, and bacteria do not get cleared through cough or sneeze; they remain in place, since they are not expelled out. Accumulation of mucus leads to infections, nasal congestions, and breathing problems
• Primary Ciliary Dyskinesia is inherited in an autosomal recessive pattern in some cases. While, in many cases, the condition occurs sporadically

Autosomal recessive: Autosomal recessive conditions are traits or disorders that occur when two copies of an abnormal gene have been inherited on a non-sex chromosome. If both parents have an autosomal recessive condition, there is a 100% likelihood of passing on the mutated genes to their children. If, however, only one mutant copy of the gene is inherited, the individual will be a carrier of the condition, but will not be present with any symptoms. Children born to two carriers, have a 25% chance of being homozygous dominant (unaffected), a 50% chance of being heterozygous (carrier), and a 25% chance of being homozygous recessive (affected).

What are the Signs and Symptoms of Primary Ciliary Dyskinesia?

The signs and symptoms of Primary Ciliary Dyskinesia may vary from one individual to another and may be mild or severe; the condition may also become severe with time. The time of onset may be during infancy and childhood (in most cases), in teenage, or even into adulthood. In rare cases, due to an absence of significant signs and symptoms, the condition may even go unnoticed or undiagnosed.

The signs and symptoms of Primary Ciliary Dyskinesia may include:

• Involvement of the nasal passages causing chronic nasal congestion, runny nose, and frequent sinus infections
• Discharge of pus from the nose and/or ear
• Ear infections and loss of hearing
• Chronic cough
• Recurrent lung infections; pneumonia
• Pneumothorax, or collapse of the lung
• Respiratory distress in neonates/newborns, observed in nearly three-fourths of the cases
• Bronchiectasis: Enlargement of a portion of the airways and lungs
• Situs inversus: In this condition, the placement of the abdomen and chest organs is abnormal. Example: The heart may be present on the right side, the liver on the left side, etc. resulting in related symptoms

How is Primary Ciliary Dyskinesia Diagnosed?

Primary Ciliary Dyskinesia is diagnosed on the basis of the following information:

• Complete physical examination and thorough medical history evaluation (family history exam)
• Assessment of signs and symptoms
• Arterial blood gases to examine the oxygen content of blood
• Lung function test
• Test for possible infections such as using sputum and blood; culture studies
• Nasal nitric oxide measurements
• Imaging studies that include X-ray of the chest, CT and MRI scan of the lungs and other affected regions
• Video microscopy to study cilia present in the airways
• Tests to measure inhaled radiolabeled particles
• Analysis of semen in males
• Molecular genetic testing to identify the gene involved

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Primary Ciliary Dyskinesia?

The complications of Primary Ciliary Dyskinesia may include:

• Recurrent and persistent airway infections
• Severe lung infection and lung damage
• Total lung collapse
• Permanent hearing loss in children
• Infertility in men due to abnormal sperm movement (observed in 50% of the males); infertility in women, due to non-functional cilia within the fallopian tube
• Heterotaxy, observed in as many as 1 in 16 cases, causing abnormal arrangement of internal organs leading to severe congenital malformations

How is Primary Ciliary Dyskinesia Treated?

A multidisciplinary approach by a team of healthcare specialists and experts from various medical fields, such as pulmonologists, ENT specialists, critical care specialists, neonatologists, and pathologists, may be necessary to diagnose and treat Primary Ciliary Dyskinesia.

There is no cure for Primary Ciliary Dyskinesia, since it is a genetic condition. The treatment is usually given to manage the signs and symptoms and any complications that develops. The goals of treatment are to control recurrent infections and clear congestion by removing trapped mucus from the airways.

The treatment measure for Primary Ciliary Dyskinesia may include:

• Chest physical therapy (CPT) that involves gently beating or drumming the chest using bare hands or a device (such as a mechanical percussor, or an inflatable therapy vest , or a special type of mask), to agitate the mucus, so that it may be coughed out
• Breathing techniques and aerobic exercises, to help loosen mucus from nasal and air passages, in order to cough out mucus
• Administration of antibiotics and anti-inflammatory medications, including nasal sprays and saline washes
• Increased fluid intake (hydration) can help treat enlarged lungs/airways (bronchiectasis)
• Bronchodilators, to help dilate the airways and relax the muscles
• Tympanostomy, to clear mucus from clogged ears and help restore hearing
• Oxygen therapy for neonatal respiratory distress conditions
• Surgery to help in sinus drainage; for severe lung disease/damage, lung transplant may be an option

Regular medical screening at periodic intervals with tests and physical examinations are essential and recommended.

How can Primary Ciliary Dyskinesia be Prevented?

Currently, Primary Ciliary Dyskinesia may not be preventable, since it is a genetic disorder.

• Genetic testing of the expecting parents (and related family members) and prenatal diagnosis (molecular testing of the fetus during pregnancy) may help in understanding the risks better during pregnancy
• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders

What is the Prognosis of Primary Ciliary Dyskinesia? (Outcomes/Resolutions)

• The prognosis of Primary Ciliary Dyskinesia is dependent upon the severity of the signs and symptoms and associated complications, if any
• Individuals with mild conditions have better prognosis than those with severe symptoms and complications
• It is reported that in many individuals, the condition may be managed well and individuals have normal lifespans
• In about 1 in 4 cases, the lungs may be severely damaged necessitating a lung transplant. In some cases, lung failure and other complications can even lead to fatalities

Additional and Relevant Useful Information for Primary Ciliary Dyskinesia:

The following DoveMed website link is a useful resource for additional information:

http://www.dovemed.com/diseases-conditions/rare-disorders/