Sleeping and breathing problems: central and obstructive sleep apnea in pura syndrome

What is the definition of PURA syndrome?

Pura syndrome was initially reported 11 years ago within a limited group of children, and since that time, slightly more children have been recognised globally as having this condition. This disorder is often associated with significant developmental delays and intellectual disabilities. Infants usually experience hypotonia, which is poor muscle tone, along with daily challenges such as feeding and breathing abnormalities. Additionally, some kids may present seizures in their early childhood years.^1,2,3 Some symptoms, such as heart defects, abnormalities of the urinary or reproductive systems, skeletal issues, and hormonal problems, might happen, although they are less frequently observed.⁴

Pura syndrome is a very uncommon genetic condition that impacts the nervous system. It is believed by scientists that genetic alterations associated with the development of brain and nerve cells are responsible for Pura syndrome.⁴ Although interventions can help the child control symptoms and minimise future complications, Pura syndrome currently does not have a cure. It may impact infants from families without prior records of the condition, but it also affects those whose parents have a high potential to transmit via their DNA, as it is a syndrome that affects the nervous system from birth.¹

What separates central apnea from obstructive apnea in people with PURA? 

Central apnea and obstructive apnea are related to sleep breathing disorders in more detail. They can be separated as follows: Central sleep apnea is a condition where breathing stops and starts again while you sleep. This is because the brain fails to send the right signals to the muscles that manage respiration. This condition is not the same as obstructive sleep apnea, where breathing slows due to the throat muscles relaxing and blocking the airway.⁵

Causes that contribute to breathing issues in patients diagnosed with PURA? 

The causes linked to breathing problems in people diagnosed with PURA syndrome, including central and obstructive sleep apnea and hypoventilation, are included.^6,7,8

• Brainstem malfunction in a neurological sense. The neurological developmental delay specific to PURA syndrome damages the brainstem, which controls involuntary activities, including breathing. This causes problems in automatically regulating breathing
• Hypotonia, which is low muscle tone, weakens the muscles needed for appropriate airway function, which causes obstructive apnea. In particular, in sleep, weak respiratory muscles increase the chance of airway breakdown, which causes breathing problems
• Infants with PURA syndrome also experience respiratory instability, which often resolves after the first year of life. Apnea can persist or recur during acute respiratory infections such as pneumonia, which aggravates breathing difficulties even more

What methods are applied To detect apnea in pura syndrome? 

In order to detect one of the sleep breathing problems in a child diagnosed with PURA syndrome, doctors mainly use respiratory studies, such as sleep research, to detect apnea. These studies, along with physical tests, such as EEG, eye exams, and possibly brain imaging (MRI), assist in evaluating respiratory function and detecting potential apnoea or other breathing issues.¹ 

The breathing research are important foundations that conduct these tests, where they evaluate people diagnosed with PURA while they are sleeping, making it easy to track and recognise the problem.³ Polysomnography is an example of sleep research, where the person is connected to devices that track their heart, lung, and brain activity, as well as the way the person breathes while sleeping. This device can also indicate movements of the arms and legs, and the level of oxygen in the blood.⁸

In the case of electroencephalography (EEG) tests, clinicians usually measure the brain’s electrical activity, where they can determine if there are seizures or additional neurological problems that could be added to apnea. 

Eye tests and MRI tests are exams that involve:¹

• Eye test: can help check for vision problems, as PURA syndrome can be linked to issues with the ability to see
• MRI test: is a machine that shows the brain’s structure in a clear image and can spot any unusual features, particularly when there is a concern about seizures or other brain-related issues

Neither the eye test nor the MRI can detect central or obstructive sleep apnoea.

Treatment and management options for its symptoms 

Currently, this syndrome has no cure; however, doctors can recommend treatments to manage its symptoms.¹ The treatment is similar to general population diagnosed with apnea, and only a healthcare specialist can diagnose and prescribe the right treatment for those diagnosed with PURA syndrome; therefore, it may include: 

• Central Apnea:⁷
  • Often associated with either immature or malfunctioning respiratory control centres, central apnea in PURA may be monitored regularly with the use of a mask that covers the nose and mouth while the person sleeps, which delivers a pressure of air with the right amount of oxygen directly to the lungs, called BiPAP or CPAP
  • Sometimes off-label drugs, such as acetazolamide or caffeine, are used to boost newborn or young kid respiration

• Obstructive Apnea:⁸ Similar approaches might be used for those with obstructive apnea. However, another option, such as
  • A mouthpiece is an oral device that helps people with mild or moderate obstructive sleep apnea. They are also used by individuals with severe apnea who are not able to wear the mask (CPAP): this device helps to keep the throat open

Some devices help keep the airway open by moving the lower jaw forward, which reduces obstructive sleep apnea whereas other devices place the tongue in a different position.

Future: what parents should expect from this syndrome

Although PURA syndrome is a neurodevelopmental disorder, which means it affects the nervous system, this syndrome can not be compared to a degenerative disorder in which individuals get worse over time. It is expected that those diagnosed with PURA will survive into adulthood, unless there are illnesses or complications in their medical history. Since PURA syndrome was discovered in 2014, foundations and researchers have found multiple people in their 20s to 50s, which increases the expectation that individuals with PURA syndrome may experience longer lifespans.

Parents of people with this syndrome should expect different behaviours, which are often linked to how much developmental delay they experience, such as the following:³

• Friendly and highly sociable
• Some kids are very sensitive to sensory input, like touch and loud sounds, and they might feel very upset when they see other kids crying
• Some may show more aggression and might hurt themselves
• Problems with sleep, such as Apnea    

FAQ’s

Can apnea in PURA syndrome improve with age?

Infants diagnosed with PURA syndrome might have excessive sleepiness, experience low body temperature, and occasionally present episodes of apnea or breathe more slowly than usual. Most of these breathing problems typically improve by the time the child reaches one year old.² 

What specialists should be involved in managing breathing issues in PURA?

Managing breathing problems in PURA syndrome patients may involve a paediatrician or paediatric neurologist to check general care, a pulmonologist with a sleep specialist to treat lung and breathing problems such as apnea, and a speech language specialist should be consulted to check the feeding or swallowing.¹ 

Summary 

A rare neurodevelopmental condition often linked to breathing problems, PURA syndrome is most usually related to central sleep apnea and less commonly to obstructive sleep apnea. The dysfunction of the brain, hypotension, and poor neuromuscular control of the airway cause these problems. Although treatment plans correspond to those used in the general population, such as CPAP, BiPAP, and, in certain cases, medicines may be needed, it can be applied for PURA patients because of their particular neurological and developmental difficulties.

This small population with PURA syndrome typically experiences central sleep apnea, which is the treatment that corresponds well to BiPAP and off-label usage of respiratory medicines such as caffeine or acetazolamide, particularly in young children.

Apnea problems should improve with age of one year in infants with PURA after a healthcare specialist diagnoses and addresses the right treatment.