Management of Pediatric Patient with Multiple Cranial, Intracranial, and Spinal Manifestations of Penttinen Syndrome: A Case Report.

Introduction: Penttinen premature aging syndrome is caused by mutations in the PDGFRB gene. We describe the case of a 10-year-old girl with a de novo c.1994T>C variant in PDGFRB who developed multiple cranial, intracranial, and spinal manifestations, including macrocephaly, enlarged convexity subarachnoid spaces crossed by numerous vascularized arachnoid trabecule, hydrocephalus, spinal epidural lipomatosis, a low conus medullaris, calvarial thinning with large anterior fontanelle, and a skull fracture with bilateral epidural hematomas. Vascularized arachnoid granulations, spinal epidural lipomatosis, and low conus medullaris have not been previously described in Penttinen syndrome.

Case presentation: A female with Penttinen syndrome diagnosed at 9 years of age initially presented as an infant with cutaneous hemangiomas and macrocephaly; imaging showed enlarged convexity subarachnoid spaces. Her convexity subarachnoid spaces continued to expand, leading to subdural shunt placement. At surgery, her enlarged subarachnoid spaces were found to contain numerous abnormally thick, vascularized arachnoid trabecule. Eventually, her subdural shunt failed and her ventricles enlarged, leading to ventricular shunt placement. A large, sunken anterior fontanelle which did not diminish in size led to cranioplasty with a custom implant. She later developed chronic back pain and imaging revealed spinal epidural lipomatosis, a low conus medullaris, and mild scoliosis. At 10 years of age, a fall from a chair resulted in a depressed skull fracture and bilateral parietal epidural hematomas. Emergency left parietal craniotomy was performed for evacuation of the left hematoma, and the patient recovered without complications. Intraoperatively, it was noted that her skull was extremely thin.

Conclusion: This case report highlights the clinical presentation and multifaceted neurosurgical management of a patient with Penttinen syndrome. The patient exhibited characteristic features including hypertrophic skin lesions, macrocephaly, and skeletal abnormalities. Our patient's vascularized arachnoid trabecule, spinal epidural lipomatosis, and low conus medullaris have not previously been reported in Penttinen syndrome. Her thin skull potentially contributed to the extent of her depressed skull fracture after her backwards fall and predisposed her toward developing epidural hematomas. Patients with Penttinen syndrome can have multiple cranial, intracranial, and spinal manifestations which may need the attention of a neurosurgeon.