Aplasia cutis congenita (ACC) is a rare congenital skin disorder that primarily affects the skin of newborns, most commonly the scalp. A skin lesion is a form of ulcer that shows the complete absence of all layers of skin, sometimes extending to the bone or dura. ACC is classified into 9 groups according to its clinical features, the presence of other malformations, and genetic disorders [1]. Therefore, it shows wide phenotypic variation. Here, we report a case of ACC with a characteristic vascular malformation.
A 1-day-old male infant was admitted to Yamaguchi University Hospital with a large scalp defect. He was born at 32 weeks of gestation by emergency cesarean delivery because of nonreassuring fetal status. Apgar score was 8 at 1 minute and 9 at 5 minutes. The infant's birth head circumference was measured at 28.0 cm, and his birth height and weight were recorded at 38.0 cm and 1,192 g, respectively. These anthropometric parameters are indicative of a small for gestational age infant. His mother did not take any oral medication before or during pregnancy. The patient had no relevant family history. After birth, the patient was treated with caffeine and non-invasive positive pressure ventilation due to severe apnea of prematurity. The defect measured 3 cm in diameter and was located in the anterior fontanelle. The cortex was visible through the defect, and the dilated veins in the vertex area were remarkable (Fig. 1A). There were no visible deformities, except for scalp defects or veins. The dilated veins were not pulsatile and were further enlarged by crying.
A moist silicone gauze with an antimicrobial ointment was administered on the first day of admission. On the 32nd day of hospitalization, the lesion was completely epithelialized (Fig. 1B). However, the skin of the vasodilated area developed crusting, and the surrounding skin became necrotic and inflamed with intermittent bleeding (Fig. 1C). Computed tomography (CT) venography revealed a junction between the dilated veins and sagittal sinus, which exacerbated the hemorrhage (Fig. 2A). Furthermore, a hypoplastic skull bone and wide dehiscence of the sagittal suture were detected (Fig. 2B). Surgery was performed to disrupt the anastomotic lesion and debride the necrotic skin, preventing further bleeding and successfully improving the lesion site (Fig. 2C). Subsequent G-banding analysis confirmed the 46, XY karyotype in this patient.
The management of ACC with bone defects poses the dilemma of selecting a conservative or surgical approach [2]. Conversely, surgical intervention is indicated for defects exceeding 4 cm in diameter or in the absence of cranial bone [3]. In this case, conservative treatment for the scalp defect was chosen initially because of the patient’s premature birth, which resulted in the epithelialization of the defect. However, surgical treatment was required to improve necrosis and hemorrhage. In addition, enlarged vessels were identified at birth and were enhanced by crying, suggesting that these vessels could be connected to the intracranial vessels. CT confirmed that contrast material flowed into the scalp veins from the sagittal sinus. The pattern of abnormal blood flow is consistent with that of sinus pericranii, which is characterized by a connection between the intracranial and extracranial veins [4]. Most cases of sinus pericranii are asymptomatic during the neonatal period. Most extracranial veins in the pericranial sinus decrease in caliber or become blind ended during cranial development. However, in the present case, the delayed ossification maintained a large outflow from the superior sagittal sinus through the channel. Increased intracranial venous pressure during crying or other Valsalva maneuvers may induce venous dilation and scalp fragility, resulting in intermittent bleeding. Life-threatening complications in ACC have been reported to include hemorrhage and infection [5]. In instances where vascular malformations are present and contribute to hemorrhage and infection, as is observed in this case, surgical intervention should be considered as a preferential treatment.
In conclusion, we report a case of ACC complicated by a unique vascular malformation and cranial hypoplasia. The assessment of complications and underlying diseases is important. If the ACC presents an atypical situation, as in our patient, surgical intervention should be considered.
Written informed consent was obtained from the parents of the patient for publication of this report and accompanying images.
Questions
Which of the following is not a common findings of sinus pericranii?
(1) The blood connection between intracranial and extracranial veins
(2) Vascular collapse caused by the elevation of intracranial
pressure
(3) Neonatal asymptomatic state
(4) Spontaneous obstruction of blood access
Answer: (2)