Medical Conditions

Pulmonary Sequestration in Children

Medically reviewed by Dr. Michael Okonkwo, MD, FAAP · Board-Certified Neonatologist

Content reviewed against published AAP, ATS, NIH guidelines

Last reviewed: May 2026

If your baby has been diagnosed with or you suspect pulmonary sequestration in children, here is what the evidence says.

The short answer

Key takeaways

Pulmonary sequestration is a mass of non-functioning lung tissue that has its own blood supply, typically from the aorta rather than the pulmonary artery. There are two types: intralobar (within the normal lung, more common) and extralobar (separate from the lung, with its own pleural covering). Sequestrations can cause recurrent pneumonia in the same location and are often found on prenatal ultrasound. Surgical removal is the definitive treatment.
Usually normal when: A small lung finding was seen on prenatal ultrasound and your doctor is monitoring it with follow-up imaging
Call your doctor if: Your newborn with a known lung mass develops breathing difficulty, rapid breathing, or appears blue, requiring emergency evaluation
Varies by age — see the age-by-age breakdown below

“Fever itself is not an illness — rather, it is a sign or symptom that the body is fighting an infection. Fever stimulates certain defenses, such as the white blood cells, which attack and destroy invading bacteria.”

— Fever and Your Child, American Academy of Pediatrics (AAP)

Parents everywhere have the same worry. You are doing the right thing by looking into it.

What Parents Should Know

According to AAP, ATS, NIH guidelines, pulmonary sequestration is a mass of non-functioning lung tissue that has its own blood supply, typically from the aorta rather than the pulmonary artery. There are two types: intralobar (within the normal lung, more common) and extralobar (separate from the lung, with its own pleural covering). Sequestrations can cause recurrent pneumonia in the same location and are often found on prenatal ultrasound. Surgical removal is the definitive treatment. At Prenatal, pulmonary sequestrations are frequently discovered during routine prenatal ultrasound, appearing as a solid mass in the lower chest (most commonly the left lower lobe). A key diagnostic feature is identifying an abnormal artery arising from the aorta that supplies the mass, which can be seen on prenatal Doppler ultrasound. Some sequestrations, particularly extralobar ones, may appear to shrink or even disappear on prenatal imaging, though the tissue is usually still present. Fetal MRI may be used for further evaluation. Most prenatally diagnosed sequestrations do not cause problems before birth. It is generally considered normal when a small lung finding was seen on prenatal ultrasound and your doctor is monitoring it with follow-up imaging. However, you should contact your pediatrician promptly if your newborn with a known lung mass develops breathing difficulty, rapid breathing, or appears blue, requiring emergency evaluation.

Sources: [1], [2], [3]

Normal vs. Concerning

Usually Normal

Worth Discussing

A small lung finding was seen on prenatal ultrasound and your doctor is monitoring it with follow-up imaging

Your newborn with a known lung mass develops breathing difficulty, rapid breathing, or appears blue, requiring emergency evaluation

Your child had a pulmonary sequestration surgically removed and has recovered well with normal breathing

Your child with a known pulmonary sequestration develops high fever, worsening cough, and difficulty breathing, which may indicate an infection in the sequestration

Your child had a single episode of pneumonia that resolved completely and has not recurred

Your child has sudden onset of severe chest pain or coughs up blood, which could indicate hemorrhage from the abnormal arterial supply to the sequestration

When to Seek Immediate Care

Your newborn with a known lung mass develops breathing difficulty, rapid breathing, or appears blue, requiring emergency evaluation
Your child with a known pulmonary sequestration develops high fever, worsening cough, and difficulty breathing, which may indicate an infection in the sequestration
Your child has sudden onset of severe chest pain or coughs up blood, which could indicate hemorrhage from the abnormal arterial supply to the sequestration

By Age

What to expect by age

Prenatal

Pulmonary sequestrations are frequently discovered during routine prenatal ultrasound, appearing as a solid mass in the lower chest (most commonly the left lower lobe). A key diagnostic feature is identifying an abnormal artery arising from the aorta that supplies the mass, which can be seen on prenatal Doppler ultrasound. Some sequestrations, particularly extralobar ones, may appear to shrink or even disappear on prenatal imaging, though the tissue is usually still present. Fetal MRI may be used for further evaluation. Most prenatally diagnosed sequestrations do not cause problems before birth.

0-3 months

Extralobar sequestrations may present with respiratory distress in the newborn period, especially if they are large or associated with other congenital abnormalities (such as congenital diaphragmatic hernia). Intralobar sequestrations are less likely to cause symptoms at birth. A CT angiogram is typically performed in the first few months of life to confirm the diagnosis and map the abnormal blood supply before surgical planning. Even if the baby is asymptomatic, evaluation is important because the sequestration may cause problems later.

3-12 months

Many pediatric surgeons recommend elective surgical removal of pulmonary sequestrations during infancy to prevent future infections. The surgery involves removing the abnormal tissue and ligating (tying off) the aberrant arterial blood supply from the aorta. Identifying and controlling this abnormal artery is critical during surgery. Intralobar sequestrations typically require lobectomy (removing the affected lobe), while extralobar sequestrations can be removed without sacrificing normal lung tissue.

1 year+

Children with undiagnosed intralobar pulmonary sequestrations may present with recurrent pneumonia that always seems to occur in the same area of the lung, typically the lower lobes. These episodes may respond to antibiotics but keep coming back. This pattern of recurrent pneumonia in the same location should raise suspicion for an underlying structural abnormality. After surgical removal, children have excellent outcomes with normal lung function from the remaining lung tissue.

What to Tell Your Pediatrician

Describe when you first noticed pulmonary sequestration in children and how it has changed over time.
Note your baby's current age and which age-specific patterns you are seeing.
Mention if a lung mass with an abnormal blood vessel was found on your baby's prenatal ultrasound and you want to discuss what to expect after birth.
Mention if your child has had two or more episodes of pneumonia in the same area of the lung, which may suggest an underlying structural abnormality.
Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
Bring a list of any questions or observations you want to discuss at the appointment.

What Should You Do?

When to take action

Probably normal when...

A small lung finding was seen on prenatal ultrasound and your doctor is monitoring it with follow-up imaging
Your child had a pulmonary sequestration surgically removed and has recovered well with normal breathing
Your child had a single episode of pneumonia that resolved completely and has not recurred

Mention at your next visit when...

A lung mass with an abnormal blood vessel was found on your baby's prenatal ultrasound and you want to discuss what to expect after birth
Your child has had two or more episodes of pneumonia in the same area of the lung, which may suggest an underlying structural abnormality
Your baby has a known pulmonary sequestration and you want to discuss timing of surgical removal
Your child had surgery for a pulmonary sequestration and you have questions about recovery and follow-up

Act now when...

Your newborn with a known lung mass develops breathing difficulty, rapid breathing, or appears blue, requiring emergency evaluation
Your child with a known pulmonary sequestration develops high fever, worsening cough, and difficulty breathing, which may indicate an infection in the sequestration
Your child has sudden onset of severe chest pain or coughs up blood, which could indicate hemorrhage from the abnormal arterial supply to the sequestration

What You Can Do at Home

Keep track of when you notice pulmonary sequestration in children — noting the time of day, duration, and any triggers can help your pediatrician.
Remember that a small lung finding was seen on prenatal ultrasound and your doctor is monitoring it with follow-up imaging — this is generally within the range of normal.
At Prenatal, focus on observation rather than intervention unless your pediatrician advises otherwise.
Follow any care instructions from your pediatrician. Keep a written log of symptoms to bring to appointments.
While monitoring at home, seek immediate care if your newborn with a known lung mass develops breathing difficulty, rapid breathing, or appears blue, requiring emergency evaluation.

Pneumonia Signs in Babies

Pneumonia is an infection of the lungs that can be caused by viruses or bacteria. Signs in babies include fever, fast or labored breathing, persistent cough, chest retractions, nasal flaring, grunting, poor feeding, and appearing more unwell than with a typical cold. If your baby is breathing fast, has visible chest retractions, or seems very sick, contact your pediatrician immediately -- pneumonia needs medical evaluation and may require antibiotics or hospitalization.

My Baby Is Breathing Fast

Babies normally breathe faster than adults. A normal respiratory rate for a newborn is 30-60 breaths per minute, slowing to 20-40 by age 1. Brief episodes of faster breathing during excitement, crying, or feeding are normal. However, persistently rapid breathing (tachypnea) at rest, especially with other signs of respiratory distress, may indicate a lung or heart problem that needs prompt evaluation.

Milestone

Month-by-Month Development

Detailed monthly development guides from birth through 24 months.

Guide

When to Call the Doctor

General guide on when to call the pediatrician, visit urgent care, or go to the ER.

Frequently asked questions

Is pulmonary sequestration in children normal?

When should I call the doctor about pulmonary sequestration in children?

Your newborn with a known lung mass develops breathing difficulty, rapid breathing, or appears blue, requiring emergency evaluation Your child with a known pulmonary sequestration develops high fever, worsening cough, and difficulty breathing, which may indicate an infection in the sequestration Your child has sudden onset of severe chest pain or coughs up blood, which could indicate hemorrhage from the abnormal arterial supply to the sequestration

When is pulmonary sequestration in children normal?

A small lung finding was seen on prenatal ultrasound and your doctor is monitoring it with follow-up imaging Your child had a pulmonary sequestration surgically removed and has recovered well with normal breathing Your child had a single episode of pneumonia that resolved completely and has not recurred

What causes pulmonary sequestration in children?

Pulmonary sequestration is a mass of non-functioning lung tissue that has its own blood supply, typically from the aorta rather than the pulmonary artery. There are two types: intralobar (within the normal lung, more common) and extralobar (separate from the lung, with its own pleural covering). Sequestrations can cause recurrent pneumonia in the same location and are often found on prenatal ultrasound. Surgical removal is the definitive treatment. Common explanations include: A small lung finding was seen on prenatal ultrasound and your doctor is monitoring it with follow-up imaging. Your child had a pulmonary sequestration surgically removed and has recovered well with normal breathing.

What should I mention to my pediatrician about pulmonary sequestration in children?

You should mention pulmonary sequestration in children at your next visit if: A lung mass with an abnormal blood vessel was found on your baby's prenatal ultrasound and you want to discuss what to expect after birth. Your child has had two or more episodes of pneumonia in the same area of the lung, which may suggest an underlying structural abnormality. Your baby has a known pulmonary sequestration and you want to discuss timing of surgical removal.

Is pulmonary sequestration in children normal at Prenatal?

Is pulmonary sequestration in children normal at 0-3 months?

Should I go to the ER for pulmonary sequestration in children?

Seek emergency care if your newborn with a known lung mass develops breathing difficulty, rapid breathing, or appears blue, requiring emergency evaluation, or if your child with a known pulmonary sequestration develops high fever, worsening cough, and difficulty breathing, which may indicate an infection in the sequestration. When in doubt, call your pediatrician's after-hours line for guidance.

Does pulmonary sequestration in children go away on its own?

In many cases, pulmonary sequestration in children resolves on its own, especially when a small lung finding was seen on prenatal ultrasound and your doctor is monitoring it with follow-up imaging. By 1 year+, children with undiagnosed intralobar pulmonary sequestrations may present with recurrent pneumonia that always seems to occur in the same area of the lung, typically the lower lobes. These episodes may respond to antibiotics but keep coming back. This pattern of recurrent pneumonia in the same location should raise suspicion for an underlying structural abnormality. After surgical removal, children have excellent outcomes with normal lung function from the remaining lung tissue.

AAP ATS NIH

References

[1]American Academy of Pediatrics. Congenital Lung Lesions: Sequestration and Related Anomalies. NeoReviews, 2019. AAP
[2]Defined by the American Thoracic Society. Congenital Thoracic Malformations. Proceedings of the American Thoracic Society, 2006. ATS
[3]National Library of Medicine. Pulmonary Sequestration. StatPearls, 2024. NIH

Doctor Visit Checklist

Bring this checklist to your next pediatrician visit to discuss Pulmonary Sequestration in Children.

Things to mention

Describe when you first noticed pulmonary sequestration in children and how it has changed over time.
Note your baby's current age and which age-specific patterns you are seeing.
Mention if a lung mass with an abnormal blood vessel was found on your baby's prenatal ultrasound and you want to discuss what to expect after birth.
Mention if your child has had two or more episodes of pneumonia in the same area of the lung, which may suggest an underlying structural abnormality.
Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
Bring a list of any questions or observations you want to discuss at the appointment.

Observations to share

A lung mass with an abnormal blood vessel was found on your baby's prenatal ultrasound and you want to discuss what to expect after birth
Your child has had two or more episodes of pneumonia in the same area of the lung, which may suggest an underlying structural abnormality
Your baby has a known pulmonary sequestration and you want to discuss timing of surgical removal

Urgent signs to report immediately

Your newborn with a known lung mass develops breathing difficulty, rapid breathing, or appears blue, requiring emergency evaluation
Your child with a known pulmonary sequestration develops high fever, worsening cough, and difficulty breathing, which may indicate an infection in the sequestration
Your child has sudden onset of severe chest pain or coughs up blood, which could indicate hemorrhage from the abnormal arterial supply to the sequestration

My notes

From ismybabyalright.com — free, evidence-based baby health guides

All content follows our editorial policy and is reviewed against published clinical guidelines.

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Bottom line

Most cases of pulmonary sequestration in children are normal. Talk to your pediatrician if your newborn with a known lung mass develops breathing difficulty, rapid breathing, or appears blue, requiring emergency evaluation.

Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.

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