ContentsSynopsisCodesLook ForDiagnostic PearlsDifferential Diagnosis & PitfallsBest TestsManagement PearlsTherapyReferencesView all Images (12)
Macrocephaly-capillary malformation in Child
Other Resources UpToDate PubMed

Macrocephaly-capillary malformation in Child

Print Images (12)
Contributors: Caitlin M. Peterman MD, Maria Cordisco MD, Susan Burgin MD
Other Resources UpToDate PubMed


Macrocephaly-capillary malformation (M-CM) consists of an enlarged head circumference and reticular capillary malformation (CM) of the face (usually central), trunk, and/or extremities. Soft tissue and/or bony overgrowth is common. Patients are often hypotonic at birth and may have developmental delay, although seizures are not seen.

M-CM is caused by a somatic mutation in PIK3CA. As such, there are no known risk factors or predisposing medical history. Reports are mixed regarding sex predominance. The condition is rare, with fewer than 200 cases in the literature.

M-CM was initially labeled as macrocephaly-cutis marmorata telangiectasia congenita (M-CMTC). The name was changed to M-CM when it was realized these patients had a CM rather than cutis marmorata telangiectasia congenita. Older literature may describe patients with M-CM as having M-CMTC, or may use another term, megalencephaly-capillary malformation-polymicrogyria (MCAP).


Q87.3 – Congenital malformation syndromes involving early overgrowth

431770003 – Fetal macrocephaly

Look For

Subscription Required

Diagnostic Pearls

Subscription Required

Differential Diagnosis & Pitfalls

  • Cutis marmorata telangiectatica congenita (CMTC) – Presents at birth in a reticulated, depressed, serpiginous pattern. Can have atrophy of the dermis and subcutis. Punctate ulcerations are possible. Fades over first year of life.
  • Sturge-Weber syndrome – Facial capillary malformation involving at least one upper eyelid and the forehead. Usually has neurological symptoms, such as seizures.
  • CLOVES syndrome (congenital lipomatous overgrowth, vascular malformations, epidermal nevi, skeletal anomalies) – Can have capillary malformations and body asymmetry but does not usually have neurological findings. Same genetic mutation.
  • Diffuse capillary malformation with overgrowth – Reticulate capillary malformation extending across multiple contiguous anatomic regions. Asymmetry / overgrowth may be present, but patients are normocephalic and lack neurological symptoms.

Best Tests

Subscription Required

Management Pearls

Subscription Required


Subscription Required


Subscription Required

Last Reviewed: 02/13/2017
Last Updated: 10/01/2019
Copyright © 2020 VisualDx®. All rights reserved.
Macrocephaly-capillary malformation in Child
Print 12 Images
View all Images (12)
(with subscription)
Macrocephaly-capillary malformation : Hyperextensible skin, Reticular configuration, Vascular plaque, Macrocephaly
Clinical image of Macrocephaly-capillary malformation
Copyright © 2020 VisualDx®. All rights reserved.