CLINICAL REPORT
Maternal and Fetal Capillary Malformation– Arteriovenous Malformation (CM–AVM) Due to a Novel RASA1 Mutation Presenting with Prenatal Non-Immune Hydrops Fetalis Rachael T. Overcash,1 Christopher K. Gibu,2 Marilyn C. Jones,3 Gladys A. Ramos,1 and Tara S. Andreasen3* 1
Division of Maternal-Fetal Medicine, Department of Reproductive Medicine, University of California, San Diego, California
2
Division of Neonatology, Department of Pediatrics, University of California, San Diego, California
3
Division of Genetics, Department of Pediatrics, University of California, San Diego, California
Manuscript Received: 2 January 2015; Manuscript Accepted: 25 May 2015
RASA1 mutations have been shown to cause capillary malformation–arteriovenous malformation (CM–AVM). We describe a patient with CM–AVM and a fetus who presented with nonimmune hydrops fetalis during the pregnancy. Sequencing revealed a novel RASA1 mutation in the RASGAP domain that results in a loss of function of p120-RasGap. This report expands our current genetic and clinical understanding of CM– AVM in pregnancy. © 2015 Wiley Periodicals, Inc.
Key words: RASA1; RasGAP; CM-AVM; capillary malforma-
How to Cite this Article: Overcash RT, Gibu CK, Jones MC, Ramos GA, Andreasen TS. 2015. Maternal and fetal capillary malformation–arteriovenous malformation (CM–AVM) due to a novel RASA1 mutation presenting with prenatal non-immune hydrops fetalis. Am J Med Genet Part A 167A:2440–2443.
tion; arteriovenous malformation; pregnancy; etiology
INTRODUCTION RASA1 mutations cause hereditary capillary malformations (CM) with or without arteriovenous malformations (AVM), arteriovenous fistulas (AVF), or Parkes–Weber syndrome (PWS). Familial occurrence of multiple CMs was initially described by Shelley and Livinghood [1949]. A limited number of reports describe families affected by CMs. The suggested pattern of inheritance is autosomal dominant with variable expressivity. Breugem et al. [2002] and Eerola et al. [2002] mapped a locus for hereditary CM to chromosome 5q. Eerola et al. [2003] subsequently identified six families with inherited CMs with some family members having AVMs, AVFs, or PWS. They described a new disorder called capillary malformation–arteriovenous malformation (CM–AVM). CM–AVM is an autosomal dominant variable disorder characterized by multifocal CMs and fast-flow lesions. Port wine stains are not often seen in patients with RASA1 mutations, instead the vascular malformations are pink to red, multiple, and round to oval. AVMs are common in the central nervous system, head, neck, skin, extremities, and spine in CM–AVM and may be life threatening. Eerola et al. [2003] identified heterozygous mutations in RASA1 in these families. RASA1 codes for p120-RasGTPase-activating
© 2015 Wiley Periodicals, Inc.
protein (p120-RasGAP), which negatively regulates the Ras/ MAP-kinase pathway. This leads to Ras activation in the endothelium and gives rise to the formation of functional microvascular networks [Anand et al., 2010]. Wijn et al. [2012] suggested RASA1 is not only a regulator of cell proliferation, but may also function in cytoskeletal reorganization, cell migration, and survival. Most reported mutations causing RASA1-related disorders are inactivating nonsense, frameshift, or splice-site mutations. The phenotypic variability can be explained by the signaling affected by RASA1 on a wide range of growth-factor receptors that play a role in cellular growth and proliferation [Eerola et al., 2003]. Revencu et al. [2013] identified 58 distinct RASA1 mutations (43 novel) in 68 index patients with a clinical diagnosis of CM–AVM. The hallmark feature of all affected family members was a CM with approximately one-third of them having fast-flow vascular lesions. This study Conflict of interest: none. Correspondence to: Tara S. Andreasen, M.S., LCGC, University of California, San Diego, Maternal-Fetal Care and Genetics, 4901 Directors Place, Suite 200, San Diego, CA 92121. E-mail: [email protected] Article first published online in Wiley Online Library (wileyonlinelibrary.com): 11 June 2015 DOI 10.1002/ajmg.a.37203
2440
OVERCASH ET AL. expanded the phenotype to include zones of pale halos with red spots in the extremities. They identified two individuals with RASA1 mutations and a family history of hydrops fetalis. Few reports have been published on CM–AVM in pregnancy. Durrington et al. [2013] described CM–AVM caused by a novel RASA1 mutation presenting with maternal complications of pulmonary microvascular shunt, worsening cutaneous CMs, and edema. Aside from increased nuchal translucency in the first trimester, the fetal development was normal. Postnatally, the infant was noted to have macroglossia, facial swelling related to a rightsided facial AVM, and several small capillary malformations on the trunk and legs. In this report, we describe a 38-year-old female with a history of CMs and AVM/AVF who presented during pregnancy with nonimmune hydrops. Postnatally, the infant was found to have a cerebral AVM and bilateral intraventricular hemorrhages (IVH). Maternal and fetal sequencing of the RASA1 gene identified a novel mutation within the RASGAP domain (c.1698 þ 2dupT), associated with CM–AVM. This report further characterizes the phenotype of CM–AVM to include non-immune hydrops fetalis and provides a mechanism for prenatal diagnosis.
CLINICAL REPORT The patient was a 38-year-old G3P1102 female who presented with an echogenic area on the interventricular cardiac septum and hydrops fetalis on ultrasound at 18 weeks 1 day. She had a bicornuate uterus, with the pregnancy identified in the right horn during first-trimester ultrasound. Obstetrical history was remarkable for spontaneous preterm delivery at 35 weeks with her first pregnancy. She delivered her second pregnancy at term, but the pregnancy was complicated by the development of lower extremity deep venous thrombosis during the mid-second trimester and unexplained polyhydramnios. Her medical history is significant for Hashimoto’s thyroiditis and a history of brain AVMs treated with coiling and embolization. Two years after the coiling and embolization, she developed an AVF requiring resection. She has a large CM covering the left side of her lower back and numerous CMs on her extremities. Her family history is significant for CMs in her daughter, five siblings, and her father (Fig. 1). No family member was known to have fast-flow lesions, nor had they undergone genetic screening. As part of her evaluation for non-immune hydrops fetalis, a fetal echocardiogram at 19 weeks gestation showed significant bilateral pleural effusions, abdominal ascites, and an echogenic area within the intra-ventricular septum thought to be secondary to an in-utero myocardial infarction (Fig. 2a and b). The fetus had asymmetric middle cerebral artery (MCA) Dopplers (Fig. 2c and d). The asymmetry was suspicious for a fetal AVM, but was not confirmatory. An amniocentesis showed a normal karyotype (46,XY), normal microarray, and negative workup for infectious etiologies. A percutaneous umbilical blood sampling procedure showed a fetal hemoglobin of 11 mg/dl, therefore, no intrauterine transfusion was performed. The fetus continued to have hydrops until 23 weeks 5 days, when it resolved spontaneously. The asymmetric MCA Dopplers, with elevation on the left side (2.2 multiples of the median), persisted. At 29 weeks 1 day, the hydrops returned with a right pleural effusion,
2441
FIG. 1. Pedigree of family demonstrating variable expression.
placentomegaly, and polyhydramnios. The left MCA Dopplers remained elevated (1.73 multiples of the median). The patient received betamethasone for fetal lung maturity at 24 weeks and a rescue course at 29 weeks. She was admitted at 32 weeks 3 days for preterm premature rupture of membranes and underwent a cesarean delivery 2 days later for persistent fetal heart rate decelerations, vaginal bleeding, and suspected placental abruption. Her postpartum course was uncomplicated. A viable male infant weighed 2,940 g. At delivery, the infant was hydropic with poor tone, no spontaneous cry, no respiratory effort, and a heart rate (HR) less than 60 beats/min. The Apgar scores were 2 and 7 at 1 and 5 min, respectively. The infant was intubated immediately after delivery for poor respiratory effort and surfactant was administered. On arrival to the neonatal intensive care unit (NICU), an initial chest X-ray demonstrated bilateral pleural effusions, pulmonary edema, and diffuse anasarca (Supplemental Figure S1). Given the presence of tense ascites, an ultrasoundguided paracentesis was performed. During the first 24 hr, the infant’s status deteriorated with increasing FiO2 requirements and worsening hypotension. A right sided chest tube was placed and dopamine was started for hypotension. A neonatal echocardiogram showed a moderate-sized patent ductus arteriosus (PDA) with bidirectional shunting, evidence of moderate pulmonary hypertension, no evidence of pericardial effusion, and an echogenicity in the interventricular septum (IVS). Results from blood, ascites, and tracheal aspirate cultures were all unremarkable. An ultrasound of the liver did not demonstrate significant findings. On day of life (DOL) 3, the infant had a head ultrasound and transcranial Doppler for the history of asymmetric left MCA Doppler flow and auscultation of a bruit over the left calvarium. The head ultrasound was unremarkable; however, the transcranial Doppler had increased velocities, a less resistive waveform, and increased diastolic flow greater in the left MCA compared to the right (Supplemental Figure S2a and b). Due to the tenuous neonatal status, further brain imaging was not completed.
2442
AMERICAN JOURNAL OF MEDICAL GENETICS PART A
FIG. 2. a: Fetal ultrasound showing hydrops fetalis with large pleural effusions and ascites. b: Fetal ultrasound showing echogenic interventricular septum (arrow) measuring 2.1 7.9 mm with pleural effusions. c: Asymmetric middle cerebral artery (MCA) Dopplers. Peak systolic velocity of the left MCA Doppler (c) was significantly elevated compared to the right MCA Doppler (d).
On DOL 8, the infant had increasing anasarca with worsening hypotension despite resuscitative efforts. A bedside echocardiogram was unable to visualize the distal aorta and had decreased Doppler flow, concerning for coarctation of the aorta prompting transfer for possible cardiac surgery. Re-evaluation did not confirm coarctation. The infant had magnetic resonance imaging (MRI)/angiography (MRA)/venography (MRV) of his brain on DOL 9, which revealed a large, high-flow left AVM coming off the left MCA, as well as mild bilateral IVHs and small areas of suspected white matter disease (Fig. 3a and b). A computed tomography (CT) angiography of the brain was obtained to further delineate the vascular anatomy, size, and flow of the AVM in preparation for surgery. The CT confirmed the findings seen on the MRI/MRA/MRV, including a 1.6 cm AVM nidus along the superficial posterior left sylvian fissure fed by multiple branches of the left MCA. The infant began to improve clinically and was weaned of pressors and extubated to nasal continuous positive airway pressure (CPAP). Given the improving clinical status and the high risk of an invasive procedure due to the infant’s prematurity and size, the decision was made to delay an operative procedure. The set forth plan was to follow the infant with serial brain MRIs to monitor for ischemic changes caused by a vascular steal phenomenon due to the AVM, which would be an indication to proceed with neurosurgery. Three repeat brain MRIs were performed which showed no significant ischemic changes or hemorrhage. An MRI of the spine was normal.
The infant did require a Nissen fundoplication and gastrostomy tube (G-tube) placement after an episode of aspiration pneumonia with a swallow study indicating aspiration. The infant had abdominal and kidney ultrasounds, which were both normal. The infant’s was discharged home on DOL 91. At 6 months of age, he underwent surgery to address the high flow lesion. He had a large arterialized vein fed directly by an artery. There was no obvious nidus but instead a transition from the arterial to venous segments and hypervascularity surrounding the AVM. After the arterial feeders were coagulated, the transition point was identified and removed. After delivery, the patient was referred for genetic screening. Given her personal and family history AVM/AVF and vascular malformations, sequencing of RASA1 was requested. ARUP Laboratory using bidirectional sequencing of all coding regions and intron–exon boundaries and identified a novel mutation within intron 12 of the RASGAP domain (c.1698þ2dupT). Computational programs (NetGene2, NNSPlice) predict this mutation to cause abnormal splicing because the nucleotide substitution occurs in the invariant region of the splice consensus sequence leading to a loss of function (hg19chr5:g. [86,665,719]; RefSeq NM_002890.1). Remaining extracted DNA from the fetal specimen obtained during the PUBS procedure was sent to ARUP for targeted analysis of the familial RASA1 mutation. The same mutation was detected in the infant, confirming the diagnosis of CM–AVM. Based on maternal cell contamination studies, no maternal cells were present, confirming the specimen to be fetal in origin.
OVERCASH ET AL.
2443 infant have had confirmatory genetic testing. Other family members are at risk for this condition and would benefit from screening.
ACKNOWLEDGMENTS We would like to thank our patient and her infant for allowing us to present their case.
REFERENCES Anand S, Majeti BK, Acevedo LM, Murphy EA, Mukthavarum R, Scheppke L, Huang M, Shields DJ, Lindquist JN, Lapinski PE, King PD, Weis SM, Cheresh DA. 2010. MicroRNA-132-mediated loss of p120RasGAP activates the endothelium to facilitate pathological angiogenesis. Nat Med 16:909–914. Breugem CC, Alders M, Salieb-Beugelaar GB, Mannens MM, Van der Horst CM, Hennekam RC. 2002. A locus for hereditary capillary malformations mapped on chromosome 5q. Hum Genet 110:343–347. Durrington HJ, First HV, Patient C, Belham M, Jayne d, Barrows N, Morrell NW, Chilvers ER. 2013. A novel RASA1 mutation causing capillary malformation-arteriovenous malformation (CM-AVM) presenting during pregnancy. Am J Med Genet Part A 161A:1690–1694.
FIG. 3. MRI (a) and MRA/venography (b) of brain on DOL 9, demonstrating a large, high-flow left AVM (black and white arrows) coming off the left middle cerebral artery.
DISCUSSION We describe CM–AVM caused by a novel mutation in RASA1 presenting with non-immune hydrops fetalis, neonatal AVM, and absent capillary malformations. This case raises several interesting points. There are multiple etiologies of non-immune hydrops fetalis, many are difficult to determine in a prenatal setting. A complete family history is necessary to determine if a vascular anomaly may be causative. This case suggests the phenotype of CM–AVM may encompass severe hydrops fetalis. Furthermore, this case illustrates that if a vascular anomaly is suspected in the fetus, prenatal color Doppler imaging may identify malformations. The relationship between type and location of mutations in RASA1 and the corresponding phenotypes has not been well established. Eerola et al. [2003] suggested the phenotypic variability may be explained by a range of growth-factor receptors that are affected by RASA1 mutations. They suggested a somatic second-hit might be necessary, as subsequently documented by Revencu et al. [2013]. The variable phenotype may reflect the specific cellular population that has undergone a complete loss of function due to a second RASA1 mutation. To our knowledge, only germline mutations in RASA1 have been reported. Finally, due to the life threatening consequences of CM–AVM, this case illustrates the importance of screening for fast-flow lesions in individuals with personal or family history of capillary malformations. Genetic counseling is necessary for these patients to understand the wide range of outcomes. Since only our patient and the
Eerola I, Boon LM, Wantanabe S, Grynberg H, Mulliken JB, Vikkula M. 2002. Locus for susceptibility for familial capillary malformation (‘portwine stain’) maps to 5q. Eur J Hum Genet 10:375–380. Eerola I, Boon LM, Mulliken JB, Burrows PE, Dompmartin A, Watanabe S, Vanwijck R, Vikkula M. 2003. Capillary malformation-arteriovenous malformation, a new clinical and genetic disorder caused by RASA1 mutations. Am J Hum Genet 73:1240–1249. Glanzer JG, Liao L, Baker T, McMulen MH, Langan As, Crandall LZ, Vorce RL. 2002. Organization and regulation of the human rasGAP gene. Gene 285:149–156. Revencu N, Boon LM, Mulliken JB, Enjolras O, Cordisco MR, Burrows PE, Clapuyt P, Hammer F, Dubois J, Baselga E, Brancati F, Carder R, Quintal JM, Dallapiccola B, Fischer G, Frieden IJ, Garzon M, Harper J, JohnsonPatel J, Labre‘ze C, Martorell L, Paltiel HJ, Pohl A, Prendiville J, Quere I, Siegel DH, Valente EM, Van Hagen A, Van Hest L, Vaux KK, Vicente A, Weibel L, Chitayat D, Vikkula M. 2008. Revencu Parkes Weber syndrome, vein of Galen aneurysmal malformation, and other fast-flow vascular anomalies are caused by RASA1 mutations. Hum Mutat 29:959–965. Revencu N, Boon LM, Mendola A, Cordisco MR, Dubois J, Clapuyt P, Hammer F, Amor DJ, Irvine AD, Baselga E, Dompmartin A, Syed S, Martin-Santiago A, Ades L, Collins F, Smith J, Sandaradura S, Barrio VR, Burrows PE, Blei F, Cozzolino M, Brunetti-Pierri N, Vicente A, Abramowicz M, Desir J, Vilain C, Chung WK, Wilson A, Gardiner CA, Dwight Y, Lord DJ, Fishman L, Cytrynbaum C, Chamlin S, Ghali F, Gilaberte Y, Joss S, Boente Mdel C, Leaute-Labreze C, Delrue MA, Bayliss S, Martorell L, Gonzalez-Ense~ nat MA, Mazereeuw-Hautier J, O’Donnell B, Bessis D, Pyeritz RE, Salhi A, Tan OT, Wargon O, Mulliken JB, Vikkula M. 2013. RASA1 mutations and associated phenotypes in 68 families with capillary malformation-arteriovenous malformation. Hum Mutat 34:1632–1641. Shelley WB, Livinghood CS. 1949. Familial multiple nevi flammei. Arch Dermatol Syph 59:343–345. Wijn RS, Oduber C, Breugem CC, Alders M, Hennekam RC, Van Der Horst CM. 2012. Phenotypic variability in a family with capillary malformations caused by a mutation in the RASA1 gene. Eur J Med Gen 55:191–195.
SUPPORTING INFORMATION Additional supporting information may be found in the online version of this article at the publisher’s web-site.
Maternal and Fetal Capillary Malformation– Arteriovenous Malformation (CM–AVM) Due to a Novel RASA1 Mutation Presenting with Prenatal Non-Immune Hydrops Fetalis Rachael T. Overcash,1 Christopher K. Gibu,2 Marilyn C. Jones,3 Gladys A. Ramos,1 and Tara S. Andreasen3* 1
Division of Maternal-Fetal Medicine, Department of Reproductive Medicine, University of California, San Diego, California
2
Division of Neonatology, Department of Pediatrics, University of California, San Diego, California
3
Division of Genetics, Department of Pediatrics, University of California, San Diego, California
Manuscript Received: 2 January 2015; Manuscript Accepted: 25 May 2015
RASA1 mutations have been shown to cause capillary malformation–arteriovenous malformation (CM–AVM). We describe a patient with CM–AVM and a fetus who presented with nonimmune hydrops fetalis during the pregnancy. Sequencing revealed a novel RASA1 mutation in the RASGAP domain that results in a loss of function of p120-RasGap. This report expands our current genetic and clinical understanding of CM– AVM in pregnancy. © 2015 Wiley Periodicals, Inc.
Key words: RASA1; RasGAP; CM-AVM; capillary malforma-
How to Cite this Article: Overcash RT, Gibu CK, Jones MC, Ramos GA, Andreasen TS. 2015. Maternal and fetal capillary malformation–arteriovenous malformation (CM–AVM) due to a novel RASA1 mutation presenting with prenatal non-immune hydrops fetalis. Am J Med Genet Part A 167A:2440–2443.
tion; arteriovenous malformation; pregnancy; etiology
INTRODUCTION RASA1 mutations cause hereditary capillary malformations (CM) with or without arteriovenous malformations (AVM), arteriovenous fistulas (AVF), or Parkes–Weber syndrome (PWS). Familial occurrence of multiple CMs was initially described by Shelley and Livinghood [1949]. A limited number of reports describe families affected by CMs. The suggested pattern of inheritance is autosomal dominant with variable expressivity. Breugem et al. [2002] and Eerola et al. [2002] mapped a locus for hereditary CM to chromosome 5q. Eerola et al. [2003] subsequently identified six families with inherited CMs with some family members having AVMs, AVFs, or PWS. They described a new disorder called capillary malformation–arteriovenous malformation (CM–AVM). CM–AVM is an autosomal dominant variable disorder characterized by multifocal CMs and fast-flow lesions. Port wine stains are not often seen in patients with RASA1 mutations, instead the vascular malformations are pink to red, multiple, and round to oval. AVMs are common in the central nervous system, head, neck, skin, extremities, and spine in CM–AVM and may be life threatening. Eerola et al. [2003] identified heterozygous mutations in RASA1 in these families. RASA1 codes for p120-RasGTPase-activating
© 2015 Wiley Periodicals, Inc.
protein (p120-RasGAP), which negatively regulates the Ras/ MAP-kinase pathway. This leads to Ras activation in the endothelium and gives rise to the formation of functional microvascular networks [Anand et al., 2010]. Wijn et al. [2012] suggested RASA1 is not only a regulator of cell proliferation, but may also function in cytoskeletal reorganization, cell migration, and survival. Most reported mutations causing RASA1-related disorders are inactivating nonsense, frameshift, or splice-site mutations. The phenotypic variability can be explained by the signaling affected by RASA1 on a wide range of growth-factor receptors that play a role in cellular growth and proliferation [Eerola et al., 2003]. Revencu et al. [2013] identified 58 distinct RASA1 mutations (43 novel) in 68 index patients with a clinical diagnosis of CM–AVM. The hallmark feature of all affected family members was a CM with approximately one-third of them having fast-flow vascular lesions. This study Conflict of interest: none. Correspondence to: Tara S. Andreasen, M.S., LCGC, University of California, San Diego, Maternal-Fetal Care and Genetics, 4901 Directors Place, Suite 200, San Diego, CA 92121. E-mail: [email protected] Article first published online in Wiley Online Library (wileyonlinelibrary.com): 11 June 2015 DOI 10.1002/ajmg.a.37203
2440
OVERCASH ET AL. expanded the phenotype to include zones of pale halos with red spots in the extremities. They identified two individuals with RASA1 mutations and a family history of hydrops fetalis. Few reports have been published on CM–AVM in pregnancy. Durrington et al. [2013] described CM–AVM caused by a novel RASA1 mutation presenting with maternal complications of pulmonary microvascular shunt, worsening cutaneous CMs, and edema. Aside from increased nuchal translucency in the first trimester, the fetal development was normal. Postnatally, the infant was noted to have macroglossia, facial swelling related to a rightsided facial AVM, and several small capillary malformations on the trunk and legs. In this report, we describe a 38-year-old female with a history of CMs and AVM/AVF who presented during pregnancy with nonimmune hydrops. Postnatally, the infant was found to have a cerebral AVM and bilateral intraventricular hemorrhages (IVH). Maternal and fetal sequencing of the RASA1 gene identified a novel mutation within the RASGAP domain (c.1698 þ 2dupT), associated with CM–AVM. This report further characterizes the phenotype of CM–AVM to include non-immune hydrops fetalis and provides a mechanism for prenatal diagnosis.
CLINICAL REPORT The patient was a 38-year-old G3P1102 female who presented with an echogenic area on the interventricular cardiac septum and hydrops fetalis on ultrasound at 18 weeks 1 day. She had a bicornuate uterus, with the pregnancy identified in the right horn during first-trimester ultrasound. Obstetrical history was remarkable for spontaneous preterm delivery at 35 weeks with her first pregnancy. She delivered her second pregnancy at term, but the pregnancy was complicated by the development of lower extremity deep venous thrombosis during the mid-second trimester and unexplained polyhydramnios. Her medical history is significant for Hashimoto’s thyroiditis and a history of brain AVMs treated with coiling and embolization. Two years after the coiling and embolization, she developed an AVF requiring resection. She has a large CM covering the left side of her lower back and numerous CMs on her extremities. Her family history is significant for CMs in her daughter, five siblings, and her father (Fig. 1). No family member was known to have fast-flow lesions, nor had they undergone genetic screening. As part of her evaluation for non-immune hydrops fetalis, a fetal echocardiogram at 19 weeks gestation showed significant bilateral pleural effusions, abdominal ascites, and an echogenic area within the intra-ventricular septum thought to be secondary to an in-utero myocardial infarction (Fig. 2a and b). The fetus had asymmetric middle cerebral artery (MCA) Dopplers (Fig. 2c and d). The asymmetry was suspicious for a fetal AVM, but was not confirmatory. An amniocentesis showed a normal karyotype (46,XY), normal microarray, and negative workup for infectious etiologies. A percutaneous umbilical blood sampling procedure showed a fetal hemoglobin of 11 mg/dl, therefore, no intrauterine transfusion was performed. The fetus continued to have hydrops until 23 weeks 5 days, when it resolved spontaneously. The asymmetric MCA Dopplers, with elevation on the left side (2.2 multiples of the median), persisted. At 29 weeks 1 day, the hydrops returned with a right pleural effusion,
2441
FIG. 1. Pedigree of family demonstrating variable expression.
placentomegaly, and polyhydramnios. The left MCA Dopplers remained elevated (1.73 multiples of the median). The patient received betamethasone for fetal lung maturity at 24 weeks and a rescue course at 29 weeks. She was admitted at 32 weeks 3 days for preterm premature rupture of membranes and underwent a cesarean delivery 2 days later for persistent fetal heart rate decelerations, vaginal bleeding, and suspected placental abruption. Her postpartum course was uncomplicated. A viable male infant weighed 2,940 g. At delivery, the infant was hydropic with poor tone, no spontaneous cry, no respiratory effort, and a heart rate (HR) less than 60 beats/min. The Apgar scores were 2 and 7 at 1 and 5 min, respectively. The infant was intubated immediately after delivery for poor respiratory effort and surfactant was administered. On arrival to the neonatal intensive care unit (NICU), an initial chest X-ray demonstrated bilateral pleural effusions, pulmonary edema, and diffuse anasarca (Supplemental Figure S1). Given the presence of tense ascites, an ultrasoundguided paracentesis was performed. During the first 24 hr, the infant’s status deteriorated with increasing FiO2 requirements and worsening hypotension. A right sided chest tube was placed and dopamine was started for hypotension. A neonatal echocardiogram showed a moderate-sized patent ductus arteriosus (PDA) with bidirectional shunting, evidence of moderate pulmonary hypertension, no evidence of pericardial effusion, and an echogenicity in the interventricular septum (IVS). Results from blood, ascites, and tracheal aspirate cultures were all unremarkable. An ultrasound of the liver did not demonstrate significant findings. On day of life (DOL) 3, the infant had a head ultrasound and transcranial Doppler for the history of asymmetric left MCA Doppler flow and auscultation of a bruit over the left calvarium. The head ultrasound was unremarkable; however, the transcranial Doppler had increased velocities, a less resistive waveform, and increased diastolic flow greater in the left MCA compared to the right (Supplemental Figure S2a and b). Due to the tenuous neonatal status, further brain imaging was not completed.
2442
AMERICAN JOURNAL OF MEDICAL GENETICS PART A
FIG. 2. a: Fetal ultrasound showing hydrops fetalis with large pleural effusions and ascites. b: Fetal ultrasound showing echogenic interventricular septum (arrow) measuring 2.1 7.9 mm with pleural effusions. c: Asymmetric middle cerebral artery (MCA) Dopplers. Peak systolic velocity of the left MCA Doppler (c) was significantly elevated compared to the right MCA Doppler (d).
On DOL 8, the infant had increasing anasarca with worsening hypotension despite resuscitative efforts. A bedside echocardiogram was unable to visualize the distal aorta and had decreased Doppler flow, concerning for coarctation of the aorta prompting transfer for possible cardiac surgery. Re-evaluation did not confirm coarctation. The infant had magnetic resonance imaging (MRI)/angiography (MRA)/venography (MRV) of his brain on DOL 9, which revealed a large, high-flow left AVM coming off the left MCA, as well as mild bilateral IVHs and small areas of suspected white matter disease (Fig. 3a and b). A computed tomography (CT) angiography of the brain was obtained to further delineate the vascular anatomy, size, and flow of the AVM in preparation for surgery. The CT confirmed the findings seen on the MRI/MRA/MRV, including a 1.6 cm AVM nidus along the superficial posterior left sylvian fissure fed by multiple branches of the left MCA. The infant began to improve clinically and was weaned of pressors and extubated to nasal continuous positive airway pressure (CPAP). Given the improving clinical status and the high risk of an invasive procedure due to the infant’s prematurity and size, the decision was made to delay an operative procedure. The set forth plan was to follow the infant with serial brain MRIs to monitor for ischemic changes caused by a vascular steal phenomenon due to the AVM, which would be an indication to proceed with neurosurgery. Three repeat brain MRIs were performed which showed no significant ischemic changes or hemorrhage. An MRI of the spine was normal.
The infant did require a Nissen fundoplication and gastrostomy tube (G-tube) placement after an episode of aspiration pneumonia with a swallow study indicating aspiration. The infant had abdominal and kidney ultrasounds, which were both normal. The infant’s was discharged home on DOL 91. At 6 months of age, he underwent surgery to address the high flow lesion. He had a large arterialized vein fed directly by an artery. There was no obvious nidus but instead a transition from the arterial to venous segments and hypervascularity surrounding the AVM. After the arterial feeders were coagulated, the transition point was identified and removed. After delivery, the patient was referred for genetic screening. Given her personal and family history AVM/AVF and vascular malformations, sequencing of RASA1 was requested. ARUP Laboratory using bidirectional sequencing of all coding regions and intron–exon boundaries and identified a novel mutation within intron 12 of the RASGAP domain (c.1698þ2dupT). Computational programs (NetGene2, NNSPlice) predict this mutation to cause abnormal splicing because the nucleotide substitution occurs in the invariant region of the splice consensus sequence leading to a loss of function (hg19chr5:g. [86,665,719]; RefSeq NM_002890.1). Remaining extracted DNA from the fetal specimen obtained during the PUBS procedure was sent to ARUP for targeted analysis of the familial RASA1 mutation. The same mutation was detected in the infant, confirming the diagnosis of CM–AVM. Based on maternal cell contamination studies, no maternal cells were present, confirming the specimen to be fetal in origin.
OVERCASH ET AL.
2443 infant have had confirmatory genetic testing. Other family members are at risk for this condition and would benefit from screening.
ACKNOWLEDGMENTS We would like to thank our patient and her infant for allowing us to present their case.
REFERENCES Anand S, Majeti BK, Acevedo LM, Murphy EA, Mukthavarum R, Scheppke L, Huang M, Shields DJ, Lindquist JN, Lapinski PE, King PD, Weis SM, Cheresh DA. 2010. MicroRNA-132-mediated loss of p120RasGAP activates the endothelium to facilitate pathological angiogenesis. Nat Med 16:909–914. Breugem CC, Alders M, Salieb-Beugelaar GB, Mannens MM, Van der Horst CM, Hennekam RC. 2002. A locus for hereditary capillary malformations mapped on chromosome 5q. Hum Genet 110:343–347. Durrington HJ, First HV, Patient C, Belham M, Jayne d, Barrows N, Morrell NW, Chilvers ER. 2013. A novel RASA1 mutation causing capillary malformation-arteriovenous malformation (CM-AVM) presenting during pregnancy. Am J Med Genet Part A 161A:1690–1694.
FIG. 3. MRI (a) and MRA/venography (b) of brain on DOL 9, demonstrating a large, high-flow left AVM (black and white arrows) coming off the left middle cerebral artery.
DISCUSSION We describe CM–AVM caused by a novel mutation in RASA1 presenting with non-immune hydrops fetalis, neonatal AVM, and absent capillary malformations. This case raises several interesting points. There are multiple etiologies of non-immune hydrops fetalis, many are difficult to determine in a prenatal setting. A complete family history is necessary to determine if a vascular anomaly may be causative. This case suggests the phenotype of CM–AVM may encompass severe hydrops fetalis. Furthermore, this case illustrates that if a vascular anomaly is suspected in the fetus, prenatal color Doppler imaging may identify malformations. The relationship between type and location of mutations in RASA1 and the corresponding phenotypes has not been well established. Eerola et al. [2003] suggested the phenotypic variability may be explained by a range of growth-factor receptors that are affected by RASA1 mutations. They suggested a somatic second-hit might be necessary, as subsequently documented by Revencu et al. [2013]. The variable phenotype may reflect the specific cellular population that has undergone a complete loss of function due to a second RASA1 mutation. To our knowledge, only germline mutations in RASA1 have been reported. Finally, due to the life threatening consequences of CM–AVM, this case illustrates the importance of screening for fast-flow lesions in individuals with personal or family history of capillary malformations. Genetic counseling is necessary for these patients to understand the wide range of outcomes. Since only our patient and the
Eerola I, Boon LM, Wantanabe S, Grynberg H, Mulliken JB, Vikkula M. 2002. Locus for susceptibility for familial capillary malformation (‘portwine stain’) maps to 5q. Eur J Hum Genet 10:375–380. Eerola I, Boon LM, Mulliken JB, Burrows PE, Dompmartin A, Watanabe S, Vanwijck R, Vikkula M. 2003. Capillary malformation-arteriovenous malformation, a new clinical and genetic disorder caused by RASA1 mutations. Am J Hum Genet 73:1240–1249. Glanzer JG, Liao L, Baker T, McMulen MH, Langan As, Crandall LZ, Vorce RL. 2002. Organization and regulation of the human rasGAP gene. Gene 285:149–156. Revencu N, Boon LM, Mulliken JB, Enjolras O, Cordisco MR, Burrows PE, Clapuyt P, Hammer F, Dubois J, Baselga E, Brancati F, Carder R, Quintal JM, Dallapiccola B, Fischer G, Frieden IJ, Garzon M, Harper J, JohnsonPatel J, Labre‘ze C, Martorell L, Paltiel HJ, Pohl A, Prendiville J, Quere I, Siegel DH, Valente EM, Van Hagen A, Van Hest L, Vaux KK, Vicente A, Weibel L, Chitayat D, Vikkula M. 2008. Revencu Parkes Weber syndrome, vein of Galen aneurysmal malformation, and other fast-flow vascular anomalies are caused by RASA1 mutations. Hum Mutat 29:959–965. Revencu N, Boon LM, Mendola A, Cordisco MR, Dubois J, Clapuyt P, Hammer F, Amor DJ, Irvine AD, Baselga E, Dompmartin A, Syed S, Martin-Santiago A, Ades L, Collins F, Smith J, Sandaradura S, Barrio VR, Burrows PE, Blei F, Cozzolino M, Brunetti-Pierri N, Vicente A, Abramowicz M, Desir J, Vilain C, Chung WK, Wilson A, Gardiner CA, Dwight Y, Lord DJ, Fishman L, Cytrynbaum C, Chamlin S, Ghali F, Gilaberte Y, Joss S, Boente Mdel C, Leaute-Labreze C, Delrue MA, Bayliss S, Martorell L, Gonzalez-Ense~ nat MA, Mazereeuw-Hautier J, O’Donnell B, Bessis D, Pyeritz RE, Salhi A, Tan OT, Wargon O, Mulliken JB, Vikkula M. 2013. RASA1 mutations and associated phenotypes in 68 families with capillary malformation-arteriovenous malformation. Hum Mutat 34:1632–1641. Shelley WB, Livinghood CS. 1949. Familial multiple nevi flammei. Arch Dermatol Syph 59:343–345. Wijn RS, Oduber C, Breugem CC, Alders M, Hennekam RC, Van Der Horst CM. 2012. Phenotypic variability in a family with capillary malformations caused by a mutation in the RASA1 gene. Eur J Med Gen 55:191–195.
SUPPORTING INFORMATION Additional supporting information may be found in the online version of this article at the publisher’s web-site.
