Skip to content
How It Works
Explore
Resources Ask a Question
Who It's For
Patients
Decode results, prep for appointments, weigh options.
Caregivers & advocates
Carry the research load for someone you love.
Providers & clinicians
Resources for patients in your practice.
Log In Ask a Question
PubMed This is a summary of 15 peer-reviewed journal articles Updated
Medical Genetics

The Three Types of Pfeiffer Syndrome: What Parents Need to Know

At a Glance

Pfeiffer syndrome is classified into three types based on severity. Type 1 is the mildest, typically allowing for normal cognitive development. Types 2 and 3 are more severe, requiring early, personalized surgical care to manage skull fusion, breathing issues, and protect brain development.

Medical professionals use a classification system to describe the range of symptoms seen in Pfeiffer syndrome. While these categories—Type 1, Type 2, and Type 3—help doctors plan for the level of care a child might need, it is important to remember that every child is an individual. Recent advances in surgical care mean that labels once used to predict “poor outcomes” are being rewritten by modern medicine [1][2].

Type 1: The “Classic” Form

Type 1 is generally considered the mildest form of the syndrome. It is often inherited from a parent, though it can occur for the first time in a child [3].

  • Physical Features: Children with Type 1 have craniosynostosis (fused skull bones) and the signature broad thumbs and big toes, but their facial features are typically less pronounced than in other types [4][5].
  • Outlook: The most encouraging fact for parents is that children with Type 1 typically have normal cognitive development and lead independent lives [3][6]. While they may need some surgeries to shape the skull or face, the neurological risks are generally lower.

Type 2: Severe with Cloverleaf Skull

Type 2 is a more severe form that is almost always a new (sporadic) mutation in the family [3].

  • Physical Features: The defining characteristic is the cloverleaf skull (also called kleeblattschädel). This happens because almost all the seams of the skull fuse too early, forcing the brain to grow upward and outward, giving the head a three-lobed appearance [4][7].
  • Complications: Children with Type 2 often face significant challenges, including extreme proptosis (bulging eyes), limited movement in the elbows, and a high risk for hydrocephalus (fluid buildup in the brain) and severe breathing issues [8][9][10].
  • Outlook: Historically, the outlook for Type 2 was considered very difficult. However, today’s “aggressive and personalized” surgical care—meaning surgeries performed very early and tailored to the child’s specific skull shape—has significantly improved survival and the potential for better developmental progress [1][2].

Type 3: Severe without Cloverleaf Skull

Type 3 is also a severe, sporadic form of the syndrome. It shares many features with Type 2 but does not include the cloverleaf skull shape [6].

  • Physical Features: These children have significant skull fusion and very shallow eye sockets, which can put the eyes at risk if not managed early [10][9].
  • Outlook: Like Type 2, children with Type 3 require intensive care from a multidisciplinary team. They are at higher risk for neurological and developmental delays due to potential brain pressure and airway obstruction, but early intervention is key to supporting their growth [3][9].

The Impact of Genetic Mutations

The specific “address” of the mutation in your child’s DNA can provide a roadmap for what to watch for.

Mutation Common Associations
FGFR2 Causes the vast majority of Pfeiffer syndrome cases, spanning the milder Type 1 through the severe Type 2 and Type 3 [4][11].
FGFR1 Very rare; exclusively associated with the milder Type 1 [12].
FGFR2 (W290C) A specific variant strongly linked to a condition called tracheal cartilaginous sleeve (TCS), where the windpipe is stiffened by extra cartilage. This requires very close monitoring of the child’s breathing [13].

A Note on Cognitive Outcomes

It is natural to worry about how this will affect your child’s intelligence. While Types 2 and 3 have a higher risk of developmental challenges, these are often “secondary” complications—meaning they are caused by things like unmanaged brain pressure, seizures, or lack of oxygen from breathing issues [9][14]. By working closely with neurosurgeons and ENT specialists to manage these risks early, the care team aims to give every child the best possible chance at reaching their full potential [2][15].

Next: Surgical Care and Treatment Priorities | Previous: Symptoms and Diagnosis | Back to Home

Common questions in this guide

What is the difference between Type 1, 2, and 3 Pfeiffer syndrome?
Type 1 is the mildest form, and children typically experience normal cognitive development. Types 2 and 3 are more severe forms that require intensive surgical care, with Type 2 being specifically distinguished by a cloverleaf skull shape.
Will my child with Pfeiffer syndrome have intellectual disabilities?
Children with Type 1 generally have normal cognitive development. In Types 2 and 3, cognitive challenges are often caused by secondary complications like unmanaged brain pressure or lack of oxygen, which is why early and aggressive surgical treatment is crucial.
What does a cloverleaf skull mean in Pfeiffer syndrome?
A cloverleaf skull, seen in Type 2 Pfeiffer syndrome, happens when almost all the seams of the skull fuse too early. This forces the brain to grow upward and outward, giving the head a distinct shape and requiring specialized surgical intervention to relieve pressure.
What causes the different types of Pfeiffer syndrome?
The syndrome is caused by genetic mutations, most commonly in the FGFR2 gene. Type 1 can be inherited from a parent or occur as a new mutation, while the more severe Types 2 and 3 are almost always new, random mutations.
What is tracheal cartilaginous sleeve (TCS)?
Tracheal cartilaginous sleeve is a serious condition where the windpipe is stiffened by extra cartilage, causing severe breathing difficulties. It requires very close respiratory monitoring and is strongly linked to a specific FGFR2 (W290C) genetic mutation.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.Based on my child's physical symptoms and genetic testing, which clinical 'type' is the most accurate classification?
  2. 2.What is the long-term plan for monitoring and protecting my child’s cognitive development?
  3. 3.How will we monitor for complications like hydrocephalus or increased brain pressure?
  4. 4.If my child has the W290C mutation, does this team have experience managing 'tracheal cartilaginous sleeve'?
  5. 5.What are the next steps if we observe any regression in developmental milestones or changes in breathing?

Questions For You

Tap a prompt to share your answer — we'll use it plus this page's context to start a tailored conversation.

References

References (15)
  1. 1

    Pfeiffer Syndrome type 2; A case report of cranio-orbitofaciostenosis with bilateral choanal atresia at Muhimbili National Hospital, Tanzania.

    Amiji I, Kalezi ZE, Abdulshakoor A, et al.

    Clinical case reports 2020; (8(9)):1613-1617 doi:10.1002/ccr3.2959.

    PMID: 32983461
  2. 2

    A genotype-specific surgical approach for patients with Pfeiffer syndrome due to W290C pathogenic variant in FGFR2 is associated with improved developmental outcomes and reduced mortality.

    Wenger TL, Hopper RA, Rosen A, et al.

    Genetics in medicine : official journal of the American College of Medical Genetics 2019; (21(2)):471-476 doi:10.1038/s41436-018-0073-x.

    PMID: 29915381
  3. 3

    Prenatal diagnosis of Pfeiffer syndrome and role of three-dimensional ultrasound: case report and review of literature.

    Vimercati A, Olivieri C, Dellino M, et al.

    The journal of maternal-fetal & neonatal medicine : the official journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians 2022; (35(25)):7840-7843 doi:10.1080/14767058.2021.1937984.

    PMID: 34182859
  4. 4

    Ophthalmic considerations in patients with Pfeiffer syndrome.

    Clark JD, Compton CJ, Tahiri Y, et al.

    American journal of ophthalmology case reports 2016; (2()):1-3 doi:10.1016/j.ajoc.2016.04.001.

    PMID: 29503887
  5. 5

    Chinese patients with p.Ala172Phe-related Pfeiffer syndrome: a case and literature review.

    Cheng SSW, Lo IF, Luk HM

    Clinical dysmorphology 2018; (27(3)):84-87 doi:10.1097/MCD.0000000000000225.

    PMID: 29782338
  6. 6

    Pfeiffer Syndrome Type 3 and Prune Belly Anomaly in a Female: Case Report and Review.

    Peña-Padilla C, Viramontes-Aguilar L, Tavares-Macías G, et al.

    Fetal and pediatric pathology 2019; (38(5)):412-417 doi:10.1080/15513815.2019.1603256.

    PMID: 31002276
  7. 7

    Kleeblattschädel in Pfeiffer syndrome type II.

    Pfeifer CM

    Radiology case reports 2020; (15(5)):474-478 doi:10.1016/j.radcr.2020.01.034.

    PMID: 32128008
  8. 8

    Pfeiffer type 2 syndrome: review with updates on its genetics and molecular biology.

    Rai R, Iwanaga J, Dupont G, et al.

    Child's nervous system : ChNS : official journal of the International Society for Pediatric Neurosurgery 2019; (35(9)):1451-1455 doi:10.1007/s00381-019-04244-7.

    PMID: 31222448
  9. 9

    Feeding, Communication, Hydrocephalus, and Intracranial Hypertension in Patients With Severe FGFR2-Associated Pfeiffer Syndrome.

    Kilcoyne S, Potter KR, Gordon Z, et al.

    The Journal of craniofacial surgery 2021; (32(1)):134-140 doi:10.1097/SCS.0000000000007153.

    PMID: 33074973
  10. 10

    The ophthalmic sequelae of Pfeiffer syndrome and the long-term visual outcomes after craniofacial surgery.

    Sharma N, Greenwell T, Hammerton M, et al.

    Journal of AAPOS : the official publication of the American Association for Pediatric Ophthalmology and Strabismus 2016; (20(4)):315-9.

    PMID: 27418250
  11. 11

    Perinatal imaging findings of a fetus with Pfeiffer syndrome and a heterozygous c.1019A>G, p.Tyr340Cys (Y340C) mutation in FGFR2 presenting a cloverleaf skull, craniosynostosis and short limbs on prenatal ultrasound mimicking thanatophoric dysplasia type II.

    Chen CP, Huang JP, Huang KS, et al.

    Taiwanese journal of obstetrics & gynecology 2024; (63(3)):387-390 doi:10.1016/j.tjog.2024.03.005.

    PMID: 38802203
  12. 12

    Familial Pfeiffer Syndrome: Variable Manifestations and Role of Multidisciplinary Team Care.

    Chaisrisawadisuk S, Moore MH

    The Cleft palate-craniofacial journal : official publication of the American Cleft Palate-Craniofacial Association 2022; (59(6)):817-820 doi:10.1177/10556656211028505.

    PMID: 34238036
  13. 13

    Tracheal cartilaginous sleeves in children with syndromic craniosynostosis.

    Wenger TL, Dahl J, Bhoj EJ, et al.

    Genetics in medicine : official journal of the American College of Medical Genetics 2017; (19(1)):62-68 doi:10.1038/gim.2016.60.

    PMID: 27228464
  14. 14

    Case report: A girl with witnessed sleep apnea.

    Wu S, Wang W, Han F, Xu L

    Frontiers in neurology 2023; (14()):1337236 doi:10.3389/fneur.2023.1337236.

    PMID: 38274866
  15. 15

    Highlighting posterior cranial vault expansion remodeling for treating various types of craniosynostosis in children.

    Yuan Y, Li Z, Gao F, et al.

    Child's nervous system : ChNS : official journal of the International Society for Pediatric Neurosurgery 2025; (41(1)):235 doi:10.1007/s00381-025-06891-5.

    PMID: 40668396

This page provides educational information about the three types of Pfeiffer syndrome. Always consult your pediatric neurosurgeon, geneticist, or specialized care team for an accurate diagnosis and customized care plan for your child.

Get notified when new evidence is published on Pfeiffer syndrome.

We monitor PubMed for new peer-reviewed studies on this topic and email a short summary when something meaningful changes.