Term Neonate with a Scalp Defect

An early-term male newborn presents with a circular scalp defect noted soon after birth that measures 0.79 × 0.55 in (2 × 1.4 cm) (Figs 1 and 2).Born to a 31-year-old primigravida mother with a benign prenatal course and negative prenatal screeningNo history of teratogens in this pregnancyNo history suggestive of any vaginal lesions (herpetic or otherwise)Level 2 antenatal ultrasonography performed at 20 weeks’ gestation was normal.Fetal growth scans were also normalBorn at 37 3/7 weeks’ gestation by elective cesarean delivery; the infant cried immediately after birth and did not need any resuscitation. Apgar scores were 8 and 9 at 1 and 5 minutes, respectively. There were no sepsis risk factorsAt birth, the infant is noted to have a circular scalp defect measuring approximately 0.79 × 0.55 in (2 × 1.4 cm) over the parietal area with deficient underlying bone. The overlying dura is intact, and there is no cerebrospinal fluid leak.Heart rate: 160 beats/minRespiratory rate: 50 breaths/minBlood pressure: 60/42 mm Hg (mean, 45 mm Hg)Oxygen saturation: 98% (in room air)Temperature: 98.6°F (37°C)Birthweight=2,880 g (24th percentile), length=18.5 in (47 cm) (6th percentile), head circumference=13.4 in (34 cm) (33rd percentile)Skin: Almost circular scalp defect measuring 0.79 × 0.55 in (2 × 1.4 cm), underlying bone also deficient; overlying dura intact; no cerebrospinal fluid leak; no erythema; no other lesionsEyes (fundus): NormalHead: Normocephalic; normal, open, soft fontanelles; symmetrical facies; patent nares; intact palate; no neck mass or crepitusOral cavity: Intact palate; normal sucking and rooting reflexLungs: Clear, equal air entry and normal breath sounds; no respiratory distressCardiovascular: Normal S1, S2; regular rate and rhythm; no murmurs or gallopAbdomen: Not distended; no organomegalyGenitourinary: Normal male genitalia; patent anusSkeletal: Spine normalNeurologic: Consolable, symmetrical Moro reflex, normal axial and appendicular strength and toneWhite blood cell count: 13,000/μL (13 × 109/L), with 31% neutrophils, 51% lymphocytesHemoglobin level: 18.2 g/dL (182 g/L)Platelet count: 302 × 103/μL (302 × 109/L)Activated partial thromboplastin time, 55.7 seconds (mean ± SD reference range, 42.6 ± 8.62 seconds); prothrombin time, 15.7 seconds (mean ± SD reference range, 12.4 ± 1.46 seconds); international normalized ratio, 1.37 (reference range, <1.5)C-reactive protein level: 0.4 mg/dL 4 mg/L (reference range, <1.0 mg/dL [<10 mg/L])Blood culture: NegativeThyrotropin sent from cord blood: 6.28 mIU/mL (reference range, 1.7–9.1 mIU/mL)Blood sent for herpes polymerase chain reaction: NegativeThe fundus and anterior segment were within normal limits.Magnetic resonance imaging of the brain was performed and showed a bilateral superior parietal lobule with few foci of acute lacunar infarcts (largest ∼9 × 5 mm on the left side). No hemorrhagic transformation was noted. The remaining brain parenchyma is normal, with normal myelination for age. The cerebral ventricles are normal, with no midline shift (Fig 3).Screening abdominal ultrasonography was normal. The screening echocardiogram was normal, including the arch, and showed a patent foramen ovale and no patent ductus arteriosus.Aplasia cutis congenitaCongenital herpesCongenital varicellaGenetic syndromeNeonatal lupusNevus sebaceousTraumaAplasia cutis congenita (ACC)The infant was evaluated by pediatric neurology, pediatric neurosurgery, and plastic surgery. The teams recommended surgery to decrease the risk of secondary infection. The blood tested negative for herpes. The infant was started on empirical antibiotics (ampicillin and amikacin). The infant had surgery under general anesthesia at 2 days of age, with neurosurgery performing the initial surgery and plastic surgery completing the closure. The skin edges were freshened (ie, a small margin around the lesion was also excised), and closure was performed in layers (Fig 4). There was minimal blood loss. Wound care was advised, including mupirocin ointment after a few days as well as cleaning the wound thoroughly with soap and water. The infant was discharged at 5 days of age with a plan for close neurodevelopmental surveillance given the possibility of seizures and the potential for vision problems. Follow-up appointments were scheduled with the pediatrician, pediatric neurosurgery, and pediatric neurology at 1, 3, and 6 months, respectively.Two weeks after discharge, the infant was noted to be gaining weight, with appropriate wound healing (Fig 5). His neurologic examination findings continue to be normal. The infant’s neurodevelopmental progress continues to be monitored closely.ACC occurs in 0.5 to 1 of 10,000 newborns. (1) It is a rare congenital anomaly with the absence of all skin layers with well-defined margins. The shape can vary, ranging from circular to linear. It can occur as 1 or more lesions on any part of the body but most commonly (70% of cases) involves the scalp. (2) The etiology is multifactorial. Teratogen exposure to carbimazole or methimazole is associated with ACC. (3) The defect can occur in isolation or as part of a genetic syndrome. In the 1980s, Frieden (4) classified ACC into 9 groups based on lesion number, location, and associated abnormalities:Group 1 – scalp ACC without other abnormalities or anomaliesGroup 2 – scalp ACC with limb abnormalitiesGroup 3 – scalp ACC with epidermoid and organoid neviGroup 4 – ACC at any site overlying embryologic malformationsGroup 5 – multiple ACC lesions with fetus papyraceus or placental infarctsGroup 6 – ACC associated with epidermolysis bullosaGroup 7 – ACC localized to the extremities without blisteringGroup 8 – ACC associated with specific teratogensGroup 9 – ACC associated with syndromes of malformation such as trisomy 13Infants with ACC require screening neuroimaging to assess for other associated abnormalities. ACC is part of SCALP syndrome (sebaceous nevus syndrome, central nervous system malformations, ACC, limbal dermoid, and pigmented nevus [giant congenital melanocytic nevus]) with neurocutaneous melanosis. (5) Affected patients can also have ocular abnormalities, including strabismus, exposure keratitis, and optic nerve hypoplasia (6); thus, an ophthalmologic examination is recommended in patients with ACC. Similarly, due to associated neurologic malformations such as polymicrogyria, neurocutaneous melanosis, and cerebral infarcts, neuroimaging and close neurodevelopmental surveillance (monitoring developmental milestones and monitoring for seizures) is warranted. Adams-Oliver syndrome is another syndrome that is associated with ACC; in this rare syndrome, affected patients have limb abnormalities along with ACC. (7) Other rare genetic disorders are associated with cardiac defects and ACC. (8) In patients without other abnormalities, the course is typically uncomplicated, with patients with large lesions requiring surgical repair. The infant in this vignette did not have any other findings and, thus, was diagnosed as having isolated ACC.ACC can appear similar to lesions found in infants with trauma due to forceps or scalp electrode use at the time of delivery, genetic syndromes, congenital herpes, congenital varicella, neonatal lupus, and nevus sebaceous. (9) This patient did not have a history of trauma during birth (cesarean delivery without the use of forceps). The possibility of syndromic association was considered, but the infant did not have any atypical features, the infant’s limbs and spine were normal, and abdominal ultrasonography demonstrated normal liver and kidneys. Hypothyroidism from maternal medications was ruled out by a normal cord thyrotropin level. Congenital herpes usually manifests as multiple skin lesions and was unlikely the cause as this infant’s blood polymerase chain reaction testing was negative. Congenital varicella consists of skin lesions, but affected patients also have ocular and limb defects, which were absent in this case. Neonatal lupus similarly presents with annular erythematous plaques, but they are usually multiple and present not just on the scalp but also on the face and over the entire body. Moreover, normal echocardiography findings made this less likely. Nevus sebaceous presents similarly as a skin lesion on the scalp with well-defined margins, but the classical feature of a wartlike patch was not present.To summarize, ACC is a rare congenital anomaly. Patients with ACC should undergo a thorough clinical examination to rule out associated limb, cardiac, eye, and other abnormalities, in addition to neuroimaging. Surgical management may be needed, and close neurodevelopmental surveillance is required.