Pierre Robin sequence: Year of the Zebra

Pierre Robin sequence describes a combination of congenital birth defects that occur during fetal development, specifically micrognathia, or underdevelopment of the lower jaw, and glossoptosis, or a backward positioned tongue, leading to airway obstruction. The cause of Pierre Robin sequence isn’t fully understood but often occurs as an isolated genetic mutation, or it can be part of a syndrome, like Stickler syndrome. 

Alright, now infants with Pierre Robin sequence have a high risk of airway obstruction due to the tendency of their tongue to slide backwards into the pharynx. In mild cases, obstruction only occurs when lying down, sleeping, or feeding, when the infant leans back into the caregiver’s arms. In severe cases, however, the obstruction can make normal breathing difficult and lead to stridor, a high-pitched whistling sound made by the collapsed airway.

Most infants with Pierre Robin sequence also have cleft palate, which is an opening in the roof of the mouth. This opening can make it difficult for the infant to suction milk from the breast or a bottle, causing poor weight gain, food aspiration, and frequent coughing and gagging. Cleft palate can also affect speech development later in life, and might contribute to frequent ear infections and even secondary hearing loss. 

Now, Pierre Robin sequence may be found on ultrasound prenatally, and if this is the case, these infants are more severely affected so further testing can be done. After birth, diagnosis is usually made based on history and physical examination. A nasolaryngoscopy, a technique where a small tube is inserted from the nose and into the throat, may be done to help locate the level and severity of airway obstruction. Further evaluation may involve radiologic imaging of the head and neck and a polysomnography, which records oxygen levels and brain activity during sleep.

Treatment of Pierre Robin sequence depends on the degree of airway obstruction. Mild cases may be treated with prone positioning, which is when the infant sleeps facing downwards. This allows the lower jaw and tongue to fall forward, moving the tongue away from the back of the pharynx.