Barw Barw Medical Journal 2960-1959 2026 06 14 Pilarowski–Bjornsson Syndrome with Congenital Heart Defect: A Case Report and Literature Review 55 59 10.58742/bmj.v4i1.229 eng Khdir Hamad Smart Health Tower (Raparin Branch), Karux Street, Ranya, Iraq |Maternity and Pediatric Teaching Hospital, Ranya, Iraq. khdir.hamad@gmail.com Sadraldin A. Braim Smart Health Tower (Raparin Branch), Karux Street, Ranya, Iraq |Directorate of Health and Safety, University of Raparin, Ranya, Iraq. Sadraldin.Braim@gmail.com Dyari Q. Hamad Smart Health Tower (Raparin Branch), Karux Street, Ranya, Sulaymaniyah, Iraq. dyari.hamad@gmail.com Araz Q. Abdalla Smart Health Tower (Raparin Branch), Karux Street, Ranya, Iraq |College of Nursing, University of Raparin, Ranya, Iraq. araz.abdalla@gmail.com Maria A. Rasool Smart Health Tower (Raparin Branch), Karux Street, Ranya, Sulaymaniyah, Iraq. maria.rasool@gmail.com Galawezh R. Hamad Smart Health Tower (Raparin Branch), Karux Street, Ranya, Iraq | Maternity and Pediatric Teaching Hospital, Ranya, Iraq. galawezh.hamad@gmail.com Karukh K. Mohammed Smart Health Tower (Raparin Branch), Karux Street, Ranya, Iraq |Kscien Organization for Scientific Research (Middle East office), Hamdi Street, Sulaymaniyah, Iraq. Karukh.mohammed@gmail.com Barham H. Bapir Smart Health Tower (Raparin Branch), Karux Street, Ranya, Sulaymaniyah, Iraq. barham.bapir@gmail.com Shadan A. Hamad Smart Health Tower (Raparin Branch), Karux Street, Ranya, Sulaymaniyah, Iraq. Shadan.hamad@gmail.com Alan Younis Department of Scientific Affairs, Smart Health Tower, Madam Mitterrand Street, Sulaymaniyah, Iraq | Department of Ward, Smart Health Tower, Madam Mitterrand Street, Sulaymaniyah, Iraq. alan.othman2001@gmail.com 2026 04 10 Introduction Pilarowski–Bjornsson syndrome (PILBOS) is a rare autosomal dominant neurodevelopmental disorder caused by heterozygous variants in chromodomain helicase DNA-binding protein 1 (CHD1), a gene encoding an adenosine triphosphate (ATP)-dependent chromatin remodeler. Since its initial description in 2018, only a limited number of cases have been reported in the literature. Case Presentation A 4-month-old male infant presented with persistent hypotonia and recurrent focal seizures beginning in the neonatal period, accompanied by severe global developmental delay. Brain magnetic resonance imaging (MRI) was structurally normal. Whole exome sequencing identified a heterozygous de novo CHD1 variant (NM_001270.4: c.797C>T; p.Pro266Leu), classified as a variant of uncertain significance. Echocardiography revealed a medium-sized secundum atrial septal defect with right-sided chamber dilatation. The clinical course was complicated by recurrent lower respiratory tract infections and progressive respiratory distress. Literature Review Review of eight previously reported cases confirms global developmental delay and hypotonia as universal features of PILBOS (8/8, 100%). Dysmorphic craniofacial findings were present in 7/8 (87.5%) cases, and seizures occurred in 3/8 (37.5%). Intellectual disability was confirmed in 3/8 (37.5%) and not assessable in a further 3/8 (37.5%). Respiratory complications were documented in 1/8 (12.5%) cases. De novo inheritance was confirmed in 4/8 (50%) cases. No structural cardiac defects have been documented in any previously reported case, and all 8/8 (100%) patients were alive at last follow-up. Conclusion Findings from this case suggest that structural congenital heart defects may represent an underrecognized component of the PILBOS phenotypic spectrum. Further case reports and functional investigations are required to establish whether cardiac involvement constitutes a consistent feature of CHD1-related disease.