A Newborn With Cyanosis

A 5-day-old, early-term male newborn weighing 2900 g presents with bluish discoloration and breathing difficulty for 1 day. He was born to a 26-year-old G2 mother in a nonconsanguineous marriage with 1 prior stillbirth. Antenatal care was adequate with normal ultrasounds, without any history of fever, rash, lymphadenopathy, joint pain, or maternal illness. Delivery was by emergency cesarean for fetal distress at 3747 weeks. The baby cried immediately at birth, and breastfeeding was initiated.The baby was asymptomatic until day 5 of life, when he develops respiratory distress and cyanosis. There are no complaints of fever, lethargy, rash, jaundice, or poor feeding. The vitals at admission are as follows: temperature 36.6 °C, heart rate 160/min, respiratory rate 72/min, SpO2 80%, mean blood pressure 48 mm Hg, and capillary refill 2 seconds. Respiratory system examination shows mild retractions and bilateral equal air entry with no added sounds. There is soft systolic murmur with normal heart sounds on cardiac examination. The findings in arterial blood gas are as follows: pH 7.36, Pco2 47 mm Hg, bicarbonate 21 mEq/L, and Po2 50 mm Hg. Father had epilepsy that was controlled on anticonvulsants.The baby presents with cyanosis and mild respiratory distress at day 5 of life. The following differentials should be considered: Cyanotic congenital heart disease: The neonate would present with cyanosis with and without respiratory distress. The diagnosis is confirmed by echocardiography.Pneumonia: It can present with cyanosis and respiratory distress. Chest radiograph and lung ultrasonography are helpful.Congenital lung malformation: It is a rare but possible cause of such presentation. The chest radiograph and advanced imaging (ie, computerized tomography and magnetic resonance imaging [MRI]) help in diagnosis.Congestive heart failure: It may result from structural heart disease, arrhythmia, cardiomyopathy, and metabolic conditions.Obstructive heart lesion: left-sided or right-sided cardiac condition (eg, pulmonary stenosis, aortic stenosis, coarctation of aorta, and hypertrophic cardiomyopathy).The baby is started on heated humidified high-flow nasal cannula at 5 L/min and 30% fraction of inspired oxygen, resulting in improvement in respiratory distress. Sepsis evaluation shows normal results for complete blood count, C-reactive protein, and blood culture. Chest radiograph, electrocardiogram, serum electrolytes, and blood glucose are normal.Echocardiography shows multiple cardiac masses involving both ventricles and interventricular septum (Figure 1). The infant gradually improves and is weaned to room air within 5 days. There are no neurocutaneous markers. Ophthalmic examination and abdominal ultrasonography are normal.Because of the association with cardiac rhabdomyoma, the family members are examined for tuberous sclerosis (TS). The father had adenoma sebaceum and epilepsy. MRI of heart and brain along with genetic testing were planned, but the family declined because of financial constraints.Multiple intracardiac masses with paternal seizures and adenoma sebaceum suggested cardiac rhabdomyoma associated with TS.Parents are counseled about risks of epilepsy and neurodevelopmental issues. At 6-month follow-up, the child had normal growth and development with no cardiac or neurological concerns.Primary cardiac tumors are extremely rare, with an incidence of 0.001% to 0.03% in autopsy series and approximately 0.15% in echocardiographic studies.1–3 In infancy, most cardiac tumors are benign, predominantly rhabdomyomas, fibromas, and teratomas. Rhabdomyomas account for 60% of all cardiac tumors and occur as a single lesion or multiple lesions in the left ventricle.4,5 The tumors are closely associated with TS and occur in more than 50% of affected patients.6–10 TS is inherited in an autosomal dominant pattern, with one-third of cases being familial and two-thirds of cases resulting from de novo mutation. The causative genes are TSC1, located on chromosome 9q34, which encodes hamartin, and TSC2, located on 16p13.3, which encodes tuberin. Mutations in TSC2 are generally associated with more severe disease. Molecular diagnosis can be made by sequencing TSC1 and TSC2 genes or using multiplex ligation probe amplification to detect large deletions/duplications.Rhabdomyomas usually appear as mobile, pedunculated ventricular masses and may be asymptomatic or present with hydrops, outflow obstruction, arrhythmias, or cardiomyopathy. Because of their association with TS, evaluation for dermatologic (adenoma sebaceum, shagreen patches), neurologic (periventricular calcifications or nodules, seizures, cerebral atrophy), and ophthalmic features (retinal phakomatosis) is essential. Dermatologic lesions may be present at birth.9The index case presented with cyanosis and diffuse cardiac rhabdomyomas along with a family history suggestive of TS (father with adenoma sebaceum). Diffuse cardiac involvement is rare but has been reported with variable presentations and outcomes.11–14 In a retrospective series of 6 neonates with cardiac rhandomyoma, all were asymptomatic at birth, and all tumors regressed spontaneously within an average of 3 years.15 In a multicentric descriptive series from Inida, 24 of 29 cases of cardiac tumors were rhabdomyoma.16 Antenatally diagnosed lesions may present postnatally with severe respiratory distress and cardiomegaly; one such case involved a large right ventricular mass encasing the great vessels with pericardial effusion requiring surgery.17 Other severe presentations include refractory supraventricular tachycardia with heart failure necessitating pacemaker placement and eventual heart transplantation12 and left ventricular outflow tract obstruction requiring prostaglandin and surgical removal on day 1 of life.18Prognosis depends on tumor number, size, location, and associated anomalies. As rhabdomyoma cells lose proliferative capacity, spontaneous regression is common.8,15 Antenatal diagnosis before fetal viability may warrant counseling regarding pregnancy termination. Asymptomatic neonates are managed conservatively; surgery is reserved for significant symptoms with an excizable mass,9 while cardiac transplantation remains a last resort.12 Mammalian target of rapamycin inhibitors such as everolimus have shown incidental tumor regression, suggesting a potential therapeutic option.19,20 All affected neonates require close follow-up, and genetic counseling is essential for future pregnancies.Diffuse cardiac rhabdomyomas are rare in neonates and are often benign in nature.The neonate should be evaluated systematically to look for other features of TS.The family members, including siblings, should also be examined for affection, as the underlying genetic condition may be there in family.Genetic counseling and prenatal diagnosis should be offered for subsequent conception.American Board of Pediatrics Neonatal-Perinatal Content SpecificationUnderstand cardiovascular physiology in regard to congestive heart failure.Know the anatomy and development of the cardiovascular system.