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Embryogenesis and types of subcostal hernia—A rare entity
Journal of Pediatric Surgery (2013) 48, 533–537
www.elsevier.com/locate/jpedsurg
Embryogenesis and types of subcostal hernia—A rare entity☆,☆☆,★ S.R. Raghu a , Anand Alladi a,⁎, Deepti Vepakomma a , O.S. Siddappa a , Preetha Tilak b a
Department of Pediatric Surgery, VaniVilas Hospital, Bangalore Medical College & Research Institute, Bangalore 560002, India b Division of Human Genetics, St John Medical College, Bangalore, India Received 13 September 2011; revised 9 August 2012; accepted 10 August 2012
Key words: Birth defects; Embryology; Subcostal hernia
Abstract Background/Purpose: Four infants with congenital subcostal hernia are reported, as it is a rare entity with only two cases previously reported. Further, there are no reports concerning the complex multisystem subtype. Embryogenesis of the associated anomalies and subcostal hernia and their management are discussed. Materials/Methods: Clinical features, history, investigations, associated anomalies, and management data of four patients with subcostal hernia were collected and analyzed. Results: The following associated anomalies were detected: renal agenesis (2), musculoskeletal abnormality (3), congenital heart disease (2), müllerian–renal–cervicothoracic somite abnormalities and vertebral–anorectal–cardiac–tracheoesophageal–renal–radial-limb anomalies (1). The subcostal hernias were treated by laparoscopic assisted (3) or laparoscopic herniorrhaphy (1). Conclusions: Subcostal hernia is a rare entity with varied clinical presentations and presents either as an isolated defect or as a complex multisystem defect. The exact etiology is still unknown. Phenotypic manifestation of the complex defect is probably due to developmental gene defect affecting the coordinated growth of mesoderm around 4th to 10th weeks of fetal life. © 2013 Elsevier Inc. All rights reserved.
Abbreviations: ARM, anorectal malformation; RA, renal agenesis; CETV, congenital talipus equinovarus; CHD, congenital heart disease; ASD, atrial septal defect; VSD, ventricular septal defect; PDA, patent ductus arteriousum; ECHO, echocardiography; CECT, contrast enhanced computerized tomography; MRI, magnetic resonance imaging; MRKH, Mayer, Rokitansky, Kuster, Hauser syndrome; MURCS association, müllerian, renal, cervicothoracic somite abnormalities; VACTERL associations, vertebral, anorectal, cardiac, tracheoesophageal, renal, radial limb; BMP, Bone morphogenetic proteins; FGFs, Fibroblast growth factors; WNT gene, hybrid of Integration1 gene and wingless gene. ☆
Source of support: Nil. Conflict of interest: None declared. ★ Consent: Obtained. ⁎ Corresponding author. Tel.: +91 9845064069. E-mail addresses: [email protected] (S.R. Raghu), [email protected] (A. Alladi), [email protected] (D. Vepakomma), [email protected] (O.S. Siddappa), [email protected] (P. Tilak). ☆☆
0022-3468/$ – see front matter © 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jpedsurg.2012.08.005
534 Astley Cooper (1804) defined hernia as a protrusion of any viscus from its proper cavity [1]. Inguinal hernia is the commonest type of neonatal hernia [2] and its reported incidence varies from 1% to 5%. Subcostal hernias are usually post-traumatic entities and rarely congenital. In our cohort, four neonates presented with a protuberant mass in the left subcostal region, with a small abdominal wall defect and herniation of its contents. To the best of our knowledge, this is the largest series of the subcostal hernias reported. In addition to reviewing the literature of congenital subcostal hernia, we also discuss the embryology, associated anomalies, and provide a new classification.
S.R. Raghu et al. investigated with a plain infant radiogram, abdominal ultrasound and ECHO. She underwent staged repair of the anorectal malformation (ARM). Diagnostic laparoscopy was carried out for completion of evaluation. The investigations revealed the occurrence of multisystem associated anomalies including agenesis of the müllerian ducts and left ovary, and congenital heart disease (ASD with tricuspid regurgitation). She also had butterfly 11th vertebra, in addition to partial sacral agenesis and left RA. The patient was a normal female with 46XX chromosomal pattern on karyotype. We performed laparoscopic repair of the subcostal abdominal wall defect. Postoperatively she had a mild residual diffuse bulge, which was attributed to early hernia recurrence. Presently she is 1.5 years old and vaginal reconstruction has been planned when she attains the age of onset of sexual intercourse.
1. Materials and methods 2.2. Case 2 Four patients with congenital subcostal hernia were admitted to our hospital between January 2009 and November 2011. The facility is a teaching medical college hospital and tertiary care center. Three cases were managed by the first author and the corresponding author while the fourth case was managed by the third and corresponding authors. The fourth and fifth authors were involved in editing the manuscript and providing inputs for the embryology. The clinical features, associated anomalies, echocardiography (ECHO), radiological findings and surgical data were collected and analyzed. All but one, were term neonates and all had an uneventful pregnancy. The family history was noncontributory. All four infants were from a close geographical area within a radius of 120 km and presented as a cluster of four cases within a short span of 1 year. The exact etiology of occurrence of four cases in the same geographic area could not be determined. Detection of the four cases may be merely co-incidental or may be influenced by some environmental or genetic factors.
A 1-day-old boy presented with respiratory distress, deformed chest, and left reducible subcostal hernia covered by hypoplastic, reddish-appearing skin (Fig. 1). Antenatal and postnatal abdominal ultrasound studies confirmed left RA. Plain radiographs of the chest and abdomen showed crowding of the left upper ribs, agenesis of 7th and 8th ribs, approximations of 11th and 12th ribs (thoracic wall defect) and a subcostal abdominal wall defect with herniation of bowel loops. The ECHO appeared to be normal. Diagnostic laparoscopy revealed a hernial orifice with a smooth margin. This was repaired by an open approach in view of the dysplastic skin which also required excision and repair (Fig. 2). However, postoperatively he succumbed to neonatal sepsis secondary to pneumonia.
2.3. Case 3 A 6-month-old boy, who was born preterm, presented with an isolated subcostal hernia and underwent a successful
2. Clinical findings and case reports All the neonates had a left subcostal hernia with a muscular defect varying from 3 to 10 cm. Antenatal sonograms (third trimester) did not pick up the hernia but left renal agenesis (RA) was detected in one fetus.
2.1. Case 1 A 2-day-old girl presented with abdominal distention, vomiting, absent anus and abnormal genitalia. Physical examination showed moderate abdominal distention, left subcostal hernia, imperforate anus, recto-vestibular fistula with vaginal agenesis and congenital talipus equinovarus (CTEV). Other systemic examination showed atrial septal defect (ASD) with tricuspid regurgitation. Initially she was
Fig. 1
Left subcostal hernia with dermal hypoplasia (arrow).
Embryogenesis and types of subcostal hernia
Fig. 2
535
Laparoscopic visualization of the muscular defect (left) and herniorrhaphy of subcostal hernia (right).
laparoscopic assisted open repair. Postoperative and followup periods were uneventful.
2.4. Case 4 A 3-day-old girl presented with respiratory distress, deformed chest, paradoxical movement of defective left chest wall and a subcostal hernia on the same side (Fig. 3). Initial evaluation with plain infant radiogram, ultrasonography and ECHO revealed multiple defects. These included scoliosis, agenesis of the left seventh rib and bifid ninth rib, ASD, ventricular septal defect (VSD), pulmonary hypertension and patent ductus arteriousus (PDA). In view of her poor cardiac status, she was initially managed conservatively. At 15 months of age her ASD, VSD and pulmonary hypertension had resolved spontaneously. Thereafter she was evaluated with a comprehensive preoperative workup consisting of plain radiographs, contrast enhanced computerized tomography (CECT) and magnetic resonance imaging (MRI). The investigations showed crowding of the upper ribs and seventh rib agenesis which resulted in a wide intercostal defect between the sixth and the eight ribs. Additionally there was a bifid ninth rib on left side. Scoliosis and fusion of T6 to T9 vertebra were noted. Both sides of the chest had a total of 11 ribs each (Fig. 4). Additional findings included syringohydromyelia and intact elevated left diaphragm with subcostal hernia (Fig. 5). The patient underwent laparoscopic repair of the hernia. She responded well and the subcostal swelling showed no evidence of recurrence when she cried. She is awaiting scoliosis repair and thoracoplasty at a later date.
The abdominal wall is formed from the somatopleurae with mesoderm invasion from myotomes on either side of vertebral column [4,5]. Mesodermal defects in early fetal life (4th to 10th weeks) could result in a defective development of abdominal wall [2,5]. Somites from para-axial mesoderm contribute to the formation of cartilages of the vertebrae and ribs, the muscles of the rib cage, limbs, abdominal wall, back and tongue. In addition to the tendons and dermis of the dorsal skin, the vascular cells which contribute to the formation of the aorta and the intervertebral blood vessels also arise from them [4]. This could possibly explain the association of the abdominal wall defect noted in our patient along with costovertebral defects and dermal hypoplasia. The intermediate mesoderm gives rise to most parts of the urogenital system [6,7]. Thoracic cage and abdominal wall defects may be associated with renal agenesis because of the intimate relationship of intermediate mesoderm with the lateral portions of the paraxial mesoderm, which gives rise to the somites. In addition, the paraxial mesoderm also contributes to the stroma of the kidney [6]. Griffin et al.
3. Discussion Nicksa et al. [2] and Monteagudo et al. [3] have reported one case each of congenital subcostal hernia making these the only previously published cases concerning this entity. Our series is the largest described in the available literature.
Fig. 3 Left subcostal hernia (bold arrow) with paradoxical chest wall movement (hollow arrow).
536
S.R. Raghu et al.
Fig. 4
CECT with 3D reconstruction showing deformed thoracic cage.
[7] noted an increased frequency of skeletal anomalies associated with renal malformations. This could explain the association of renal agenesis with musculoskeletal abnormalities. Isolated subcostal hernia was probably due to a late embryological localized vascular event. RA in females may be associated with genital anomalies like absence of the vagina (51.3%), uterus (40.1%) one or both tubes (25.6%) and one or both ovaries (23.1%) [2,8]. Mayer–Rokitansky–Kuster–Hauser (MRKH) syndrome is subdivided in two types, based on whether it is a single defect or associated with multiple system anomalies. Accordingly, type I is ‘isolated’ and type II is also known
Fig. 5
as müllerian–renal–cervicothoracic somite abnormalities (MURCS association) [9]. MURCS association was defined by Duncan et al. [10] as müllerian and renal agenesis along with malformations of the skeleton. Others have reported variable involvement of heart, muscular weakness, CTEV and inguinal hernia [9-11]. The etiology may be due to initial global affection of somites, intermediate and lateral plate mesoderm. This is hypothesized to occur around fourth week of life, due to their geographical proximity and may result from a sporadic event, genetic or environmental factor(s) [4,7,9–11]. This is the first description of hither to unreported MURCS and vertebral–anorectal–cardiac–
MRI showing left subcostal hernia, left intact diaphragm and syringohydromyelia.
Embryogenesis and types of subcostal hernia tracheoesophageal–renal–radial-limb (VACTERL) associations together in a female with a subcostal hernia [11]. Coordinated expression of sonic hedgehog, neurotrophin 3 (neural tube), bone morphogenetic proteins (BMP-4), fibroblast growth factors (FGFs) (lateral plate mesoderm) and WNT gene (hybrid of integration1 gene and wingless gene) (epidermis) signals are necessary for mesodermal differentiation [4,6,12-14]. It is likely that some or all of these genes might be affected in early embryonic life and may be the probable cause for the clinical presentation. Determination of the probable mutations in the developmental genes was not possible in our setting. Further, conclusive genetic diagnosis could not be derived after searching Mendelian Inheritance in Man (online reference), London dysmorphology and POSSUM databases to determine if it was a single syndrome with all these manifestations. Thus it was also not possible to classify if the reported cases were sporadic in occurrence or due to disruption/ mutations of the genes during development. Congenital birth defects can be classified in various ways [15]. According to the classification based on clinical presentation, our series includes two different embryological groups. In one patient it was a single system defect probably resulting from an isolated late vascular insult causing a localized defect without any associations. The other three patients had complex multisystem defects, possibly arising out of deleterious action of the gene(s) expressed during development, on structures of different embryologic origin but sharing the same geographic location [4,7,9-11,15]. We have proposed an algorithm for evaluation of subcostal hernia according to which delayed reconstructive or staged surgery would be suitable in large defects and multisystem congenital birth defects. If the prenatal ultrasonography detects subcostal hernia, a fetal MRI is recommended to evaluate the severity and associated anomalies. Subcostal hernia is a very rare entity presenting as an isolated defect or a complex multisystem defect, the exact etiology of which is still unknown. However, a few speculations have been made. Phenotypic manifestation of the complex defect is probably due to a developmental gene
537 defect affecting coordinated growth of mesoderm around the 4th to 10th weeks of embryonic life.
References [1] Eubanks S. Hernias. In: Sabiston DC, Lyrly HK, editors. Sabiston's textbook of surgery: the biological basis of modern surgical practice. 15th ed. Philadelphia: W.B.Saunders; 1997. p. 1216-9. [2] Nicksa GA, Christensen EP, Buchmiller TL. A case report of a congenital left subcostal hernia in a neonate. J Pediatr Surg 2009;44: 1653-5. [3] Monteagudo J, Ruscher KA, Margolis E, et al. Congenital subcostal hernia with unusual contents. J Pediatr Surg 2010;45:435-7. [4] Third to eighth weeks: the embryonic period. In: Sadler TW, editor. Langman's medical embryology. 11th ed. India: Wolters Kluwer/ Lippincott William & Wilkins; 2011. p. 67-90. [5] Grevious MA, Cohen M, Shah SR, et al. Structural and functional anatomy of the abdominal wall. Clin Plast Surg 2006;33:169-79. [6] Guillaume R, Bressan M, Herzlinger D. Paraxial mesoderm contributes stromal cells to the developing kidney. Dev Biol 2009;329:169-75. [7] Griffin JE, Edwards C, Madden JD, et al. Congenital absence of the vagina. The Mayer–Rokitansky–Kuster–Hauser syndrome. Ann Intern Med 1976;85:224-6. [8] Parrott TS, Skandalakis JE, Gray SW. The kidney and ureter. In: Skandalakis JE, Gray SW, editors. Embryology for surgeons. 2nd ed. Baltimore Md: Williams & Wilkins; 1994. p. 594-612. [9] Oppelt P, Renner SP, Kellermann A, et al. Clinical aspects of Mayer– Rokitansky–Kuester–Hauser syndrome: recommendations for clinical diagnosis and staging. Hum Reprod 2006;21:792-7. [10] Duncan PA, Shapiro LR, Stangel JJ, et al. The MURCS association: müllerian duct aplasia, renal aplasia, and cervicothoracic somite dysplasia. J Pediatr 1979;95:399-402. [11] Morcel K, Camborieux L. Programme de Recherches sur les Aplasies Müllériennes, Guerrier D. Mayer–Rokitansky–Küster–Hauser (MRKH) syndrome. Orphanet J Rare Dis 2007;2:13. [12] Komura M, Kanamori Y, Sugiyama M, et al. A female infant who had both complete VACTERL association and MURCS association: report of a case. Surg Today 2007;37:878. [13] Costantini F, Kopan R. Patterning a complex organ: branching morphogenesis and nephron segmentation in kidney development. Dev Cell 2010;18:698-712. [14] Kornak U, Mundlos S. Genetic disorders of the skeleton: a developmental approach. Am J Hum Genet 2003;73:447-74. [15] Tanteles GA, Suri M. Classification and aetiology of birth defects. Paediatrics Child Health 2007;17:233-43.
www.elsevier.com/locate/jpedsurg
Embryogenesis and types of subcostal hernia—A rare entity☆,☆☆,★ S.R. Raghu a , Anand Alladi a,⁎, Deepti Vepakomma a , O.S. Siddappa a , Preetha Tilak b a
Department of Pediatric Surgery, VaniVilas Hospital, Bangalore Medical College & Research Institute, Bangalore 560002, India b Division of Human Genetics, St John Medical College, Bangalore, India Received 13 September 2011; revised 9 August 2012; accepted 10 August 2012
Key words: Birth defects; Embryology; Subcostal hernia
Abstract Background/Purpose: Four infants with congenital subcostal hernia are reported, as it is a rare entity with only two cases previously reported. Further, there are no reports concerning the complex multisystem subtype. Embryogenesis of the associated anomalies and subcostal hernia and their management are discussed. Materials/Methods: Clinical features, history, investigations, associated anomalies, and management data of four patients with subcostal hernia were collected and analyzed. Results: The following associated anomalies were detected: renal agenesis (2), musculoskeletal abnormality (3), congenital heart disease (2), müllerian–renal–cervicothoracic somite abnormalities and vertebral–anorectal–cardiac–tracheoesophageal–renal–radial-limb anomalies (1). The subcostal hernias were treated by laparoscopic assisted (3) or laparoscopic herniorrhaphy (1). Conclusions: Subcostal hernia is a rare entity with varied clinical presentations and presents either as an isolated defect or as a complex multisystem defect. The exact etiology is still unknown. Phenotypic manifestation of the complex defect is probably due to developmental gene defect affecting the coordinated growth of mesoderm around 4th to 10th weeks of fetal life. © 2013 Elsevier Inc. All rights reserved.
Abbreviations: ARM, anorectal malformation; RA, renal agenesis; CETV, congenital talipus equinovarus; CHD, congenital heart disease; ASD, atrial septal defect; VSD, ventricular septal defect; PDA, patent ductus arteriousum; ECHO, echocardiography; CECT, contrast enhanced computerized tomography; MRI, magnetic resonance imaging; MRKH, Mayer, Rokitansky, Kuster, Hauser syndrome; MURCS association, müllerian, renal, cervicothoracic somite abnormalities; VACTERL associations, vertebral, anorectal, cardiac, tracheoesophageal, renal, radial limb; BMP, Bone morphogenetic proteins; FGFs, Fibroblast growth factors; WNT gene, hybrid of Integration1 gene and wingless gene. ☆
Source of support: Nil. Conflict of interest: None declared. ★ Consent: Obtained. ⁎ Corresponding author. Tel.: +91 9845064069. E-mail addresses: [email protected] (S.R. Raghu), [email protected] (A. Alladi), [email protected] (D. Vepakomma), [email protected] (O.S. Siddappa), [email protected] (P. Tilak). ☆☆
0022-3468/$ – see front matter © 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jpedsurg.2012.08.005
534 Astley Cooper (1804) defined hernia as a protrusion of any viscus from its proper cavity [1]. Inguinal hernia is the commonest type of neonatal hernia [2] and its reported incidence varies from 1% to 5%. Subcostal hernias are usually post-traumatic entities and rarely congenital. In our cohort, four neonates presented with a protuberant mass in the left subcostal region, with a small abdominal wall defect and herniation of its contents. To the best of our knowledge, this is the largest series of the subcostal hernias reported. In addition to reviewing the literature of congenital subcostal hernia, we also discuss the embryology, associated anomalies, and provide a new classification.
S.R. Raghu et al. investigated with a plain infant radiogram, abdominal ultrasound and ECHO. She underwent staged repair of the anorectal malformation (ARM). Diagnostic laparoscopy was carried out for completion of evaluation. The investigations revealed the occurrence of multisystem associated anomalies including agenesis of the müllerian ducts and left ovary, and congenital heart disease (ASD with tricuspid regurgitation). She also had butterfly 11th vertebra, in addition to partial sacral agenesis and left RA. The patient was a normal female with 46XX chromosomal pattern on karyotype. We performed laparoscopic repair of the subcostal abdominal wall defect. Postoperatively she had a mild residual diffuse bulge, which was attributed to early hernia recurrence. Presently she is 1.5 years old and vaginal reconstruction has been planned when she attains the age of onset of sexual intercourse.
1. Materials and methods 2.2. Case 2 Four patients with congenital subcostal hernia were admitted to our hospital between January 2009 and November 2011. The facility is a teaching medical college hospital and tertiary care center. Three cases were managed by the first author and the corresponding author while the fourth case was managed by the third and corresponding authors. The fourth and fifth authors were involved in editing the manuscript and providing inputs for the embryology. The clinical features, associated anomalies, echocardiography (ECHO), radiological findings and surgical data were collected and analyzed. All but one, were term neonates and all had an uneventful pregnancy. The family history was noncontributory. All four infants were from a close geographical area within a radius of 120 km and presented as a cluster of four cases within a short span of 1 year. The exact etiology of occurrence of four cases in the same geographic area could not be determined. Detection of the four cases may be merely co-incidental or may be influenced by some environmental or genetic factors.
A 1-day-old boy presented with respiratory distress, deformed chest, and left reducible subcostal hernia covered by hypoplastic, reddish-appearing skin (Fig. 1). Antenatal and postnatal abdominal ultrasound studies confirmed left RA. Plain radiographs of the chest and abdomen showed crowding of the left upper ribs, agenesis of 7th and 8th ribs, approximations of 11th and 12th ribs (thoracic wall defect) and a subcostal abdominal wall defect with herniation of bowel loops. The ECHO appeared to be normal. Diagnostic laparoscopy revealed a hernial orifice with a smooth margin. This was repaired by an open approach in view of the dysplastic skin which also required excision and repair (Fig. 2). However, postoperatively he succumbed to neonatal sepsis secondary to pneumonia.
2.3. Case 3 A 6-month-old boy, who was born preterm, presented with an isolated subcostal hernia and underwent a successful
2. Clinical findings and case reports All the neonates had a left subcostal hernia with a muscular defect varying from 3 to 10 cm. Antenatal sonograms (third trimester) did not pick up the hernia but left renal agenesis (RA) was detected in one fetus.
2.1. Case 1 A 2-day-old girl presented with abdominal distention, vomiting, absent anus and abnormal genitalia. Physical examination showed moderate abdominal distention, left subcostal hernia, imperforate anus, recto-vestibular fistula with vaginal agenesis and congenital talipus equinovarus (CTEV). Other systemic examination showed atrial septal defect (ASD) with tricuspid regurgitation. Initially she was
Fig. 1
Left subcostal hernia with dermal hypoplasia (arrow).
Embryogenesis and types of subcostal hernia
Fig. 2
535
Laparoscopic visualization of the muscular defect (left) and herniorrhaphy of subcostal hernia (right).
laparoscopic assisted open repair. Postoperative and followup periods were uneventful.
2.4. Case 4 A 3-day-old girl presented with respiratory distress, deformed chest, paradoxical movement of defective left chest wall and a subcostal hernia on the same side (Fig. 3). Initial evaluation with plain infant radiogram, ultrasonography and ECHO revealed multiple defects. These included scoliosis, agenesis of the left seventh rib and bifid ninth rib, ASD, ventricular septal defect (VSD), pulmonary hypertension and patent ductus arteriousus (PDA). In view of her poor cardiac status, she was initially managed conservatively. At 15 months of age her ASD, VSD and pulmonary hypertension had resolved spontaneously. Thereafter she was evaluated with a comprehensive preoperative workup consisting of plain radiographs, contrast enhanced computerized tomography (CECT) and magnetic resonance imaging (MRI). The investigations showed crowding of the upper ribs and seventh rib agenesis which resulted in a wide intercostal defect between the sixth and the eight ribs. Additionally there was a bifid ninth rib on left side. Scoliosis and fusion of T6 to T9 vertebra were noted. Both sides of the chest had a total of 11 ribs each (Fig. 4). Additional findings included syringohydromyelia and intact elevated left diaphragm with subcostal hernia (Fig. 5). The patient underwent laparoscopic repair of the hernia. She responded well and the subcostal swelling showed no evidence of recurrence when she cried. She is awaiting scoliosis repair and thoracoplasty at a later date.
The abdominal wall is formed from the somatopleurae with mesoderm invasion from myotomes on either side of vertebral column [4,5]. Mesodermal defects in early fetal life (4th to 10th weeks) could result in a defective development of abdominal wall [2,5]. Somites from para-axial mesoderm contribute to the formation of cartilages of the vertebrae and ribs, the muscles of the rib cage, limbs, abdominal wall, back and tongue. In addition to the tendons and dermis of the dorsal skin, the vascular cells which contribute to the formation of the aorta and the intervertebral blood vessels also arise from them [4]. This could possibly explain the association of the abdominal wall defect noted in our patient along with costovertebral defects and dermal hypoplasia. The intermediate mesoderm gives rise to most parts of the urogenital system [6,7]. Thoracic cage and abdominal wall defects may be associated with renal agenesis because of the intimate relationship of intermediate mesoderm with the lateral portions of the paraxial mesoderm, which gives rise to the somites. In addition, the paraxial mesoderm also contributes to the stroma of the kidney [6]. Griffin et al.
3. Discussion Nicksa et al. [2] and Monteagudo et al. [3] have reported one case each of congenital subcostal hernia making these the only previously published cases concerning this entity. Our series is the largest described in the available literature.
Fig. 3 Left subcostal hernia (bold arrow) with paradoxical chest wall movement (hollow arrow).
536
S.R. Raghu et al.
Fig. 4
CECT with 3D reconstruction showing deformed thoracic cage.
[7] noted an increased frequency of skeletal anomalies associated with renal malformations. This could explain the association of renal agenesis with musculoskeletal abnormalities. Isolated subcostal hernia was probably due to a late embryological localized vascular event. RA in females may be associated with genital anomalies like absence of the vagina (51.3%), uterus (40.1%) one or both tubes (25.6%) and one or both ovaries (23.1%) [2,8]. Mayer–Rokitansky–Kuster–Hauser (MRKH) syndrome is subdivided in two types, based on whether it is a single defect or associated with multiple system anomalies. Accordingly, type I is ‘isolated’ and type II is also known
Fig. 5
as müllerian–renal–cervicothoracic somite abnormalities (MURCS association) [9]. MURCS association was defined by Duncan et al. [10] as müllerian and renal agenesis along with malformations of the skeleton. Others have reported variable involvement of heart, muscular weakness, CTEV and inguinal hernia [9-11]. The etiology may be due to initial global affection of somites, intermediate and lateral plate mesoderm. This is hypothesized to occur around fourth week of life, due to their geographical proximity and may result from a sporadic event, genetic or environmental factor(s) [4,7,9–11]. This is the first description of hither to unreported MURCS and vertebral–anorectal–cardiac–
MRI showing left subcostal hernia, left intact diaphragm and syringohydromyelia.
Embryogenesis and types of subcostal hernia tracheoesophageal–renal–radial-limb (VACTERL) associations together in a female with a subcostal hernia [11]. Coordinated expression of sonic hedgehog, neurotrophin 3 (neural tube), bone morphogenetic proteins (BMP-4), fibroblast growth factors (FGFs) (lateral plate mesoderm) and WNT gene (hybrid of integration1 gene and wingless gene) (epidermis) signals are necessary for mesodermal differentiation [4,6,12-14]. It is likely that some or all of these genes might be affected in early embryonic life and may be the probable cause for the clinical presentation. Determination of the probable mutations in the developmental genes was not possible in our setting. Further, conclusive genetic diagnosis could not be derived after searching Mendelian Inheritance in Man (online reference), London dysmorphology and POSSUM databases to determine if it was a single syndrome with all these manifestations. Thus it was also not possible to classify if the reported cases were sporadic in occurrence or due to disruption/ mutations of the genes during development. Congenital birth defects can be classified in various ways [15]. According to the classification based on clinical presentation, our series includes two different embryological groups. In one patient it was a single system defect probably resulting from an isolated late vascular insult causing a localized defect without any associations. The other three patients had complex multisystem defects, possibly arising out of deleterious action of the gene(s) expressed during development, on structures of different embryologic origin but sharing the same geographic location [4,7,9-11,15]. We have proposed an algorithm for evaluation of subcostal hernia according to which delayed reconstructive or staged surgery would be suitable in large defects and multisystem congenital birth defects. If the prenatal ultrasonography detects subcostal hernia, a fetal MRI is recommended to evaluate the severity and associated anomalies. Subcostal hernia is a very rare entity presenting as an isolated defect or a complex multisystem defect, the exact etiology of which is still unknown. However, a few speculations have been made. Phenotypic manifestation of the complex defect is probably due to a developmental gene
537 defect affecting coordinated growth of mesoderm around the 4th to 10th weeks of embryonic life.
References [1] Eubanks S. Hernias. In: Sabiston DC, Lyrly HK, editors. Sabiston's textbook of surgery: the biological basis of modern surgical practice. 15th ed. Philadelphia: W.B.Saunders; 1997. p. 1216-9. [2] Nicksa GA, Christensen EP, Buchmiller TL. A case report of a congenital left subcostal hernia in a neonate. J Pediatr Surg 2009;44: 1653-5. [3] Monteagudo J, Ruscher KA, Margolis E, et al. Congenital subcostal hernia with unusual contents. J Pediatr Surg 2010;45:435-7. [4] Third to eighth weeks: the embryonic period. In: Sadler TW, editor. Langman's medical embryology. 11th ed. India: Wolters Kluwer/ Lippincott William & Wilkins; 2011. p. 67-90. [5] Grevious MA, Cohen M, Shah SR, et al. Structural and functional anatomy of the abdominal wall. Clin Plast Surg 2006;33:169-79. [6] Guillaume R, Bressan M, Herzlinger D. Paraxial mesoderm contributes stromal cells to the developing kidney. Dev Biol 2009;329:169-75. [7] Griffin JE, Edwards C, Madden JD, et al. Congenital absence of the vagina. The Mayer–Rokitansky–Kuster–Hauser syndrome. Ann Intern Med 1976;85:224-6. [8] Parrott TS, Skandalakis JE, Gray SW. The kidney and ureter. In: Skandalakis JE, Gray SW, editors. Embryology for surgeons. 2nd ed. Baltimore Md: Williams & Wilkins; 1994. p. 594-612. [9] Oppelt P, Renner SP, Kellermann A, et al. Clinical aspects of Mayer– Rokitansky–Kuester–Hauser syndrome: recommendations for clinical diagnosis and staging. Hum Reprod 2006;21:792-7. [10] Duncan PA, Shapiro LR, Stangel JJ, et al. The MURCS association: müllerian duct aplasia, renal aplasia, and cervicothoracic somite dysplasia. J Pediatr 1979;95:399-402. [11] Morcel K, Camborieux L. Programme de Recherches sur les Aplasies Müllériennes, Guerrier D. Mayer–Rokitansky–Küster–Hauser (MRKH) syndrome. Orphanet J Rare Dis 2007;2:13. [12] Komura M, Kanamori Y, Sugiyama M, et al. A female infant who had both complete VACTERL association and MURCS association: report of a case. Surg Today 2007;37:878. [13] Costantini F, Kopan R. Patterning a complex organ: branching morphogenesis and nephron segmentation in kidney development. Dev Cell 2010;18:698-712. [14] Kornak U, Mundlos S. Genetic disorders of the skeleton: a developmental approach. Am J Hum Genet 2003;73:447-74. [15] Tanteles GA, Suri M. Classification and aetiology of birth defects. Paediatrics Child Health 2007;17:233-43.