Rapid-onset obesity with hypothalamic dysfunction, hypoventilation, and autonomic dysregulation (ROHHAD) syndrome may have a hypothalamus-periaqueductal gray localization.
BACKGROUND
Anatomical localization of the rapid-onset obesity with hypothalamic dysfunction, hypoventilation, and autonomic dysregulation (ROHHAD) syndrome has proved elusive. Most patients had neuroimaging after cardiorespiratory collapse, revealing a range of ischemic lesions.


METHODS
A 15-year-old obese boy with an acute febrile encephalopathy had hypoventilation, autonomic dysfunction, visual hallucinations, hyperekplexia, and disordered body temperature, and saltwater regulation. These features describe the ROHHAD syndrome. Cerebrospinal fluid analysis showed pleocytosis, elevated neopterins, and oligoclonal bands, and serology for systemic and antineuronal antibodies was negative. He improved after receiving intravenous steroids, immunoglobulins, and long-term mycophenolate. Screening for neural crest tumors was negative.


CONCLUSIONS
Magnetic resonance imaging of the brain early in his illness showed focal inflammation in the periaqueductal gray matter and hypothalamus. This unique localization explains almost all symptoms of this rare autoimmune encephalitis.
Neurology Service, Department of Paediatrics, KK Women's and Children's Hospital, Singapore.
Cristelle
C
Chow
Department of Diagnostic Imaging, KK Women's and Children's Hospital, Singapore.
Marielle Valerie
MV
Fortier
Rheumatology and Immunology Service, Department of Paediatric Subspecialties, KK Women's and Children's Hospital, Singapore.
Lena
L
Das
Children's Intensive Care Unit, Department of Paediatric Subspecialties, KK Women's and Children's Hospital, Singapore.
Anuradha P
AP
Menon
Endocrine Service, Department of Paediatrics, KK Women's and Children's Hospital, Singapore.
Rashida
R
Vasanwala
Haematology and Oncology Service, Department of Paediatric Subspecialties, KK Women's and Children's Hospital, Singapore.
Joyce C M
JC
Lam
Department of Paediatrics, KK Women's and Children's Hospital, Singapore.
Zhi Min
ZM
Ng
Neurology Service, Department of Paediatrics, KK Women's and Children's Hospital, Singapore.
Simon Robert
SR
Ling
Neurology Service, Department of Paediatrics, KK Women's and Children's Hospital, Singapore.
Derrick W S
DW
Chan
Neurology Service, Department of Paediatrics, KK Women's and Children's Hospital, Singapore.
Chew Thye
CT
Choong
Neurology Service, Department of Paediatrics, KK Women's and Children's Hospital, Singapore.
Wendy K M
WK
Liew
Neurology Service, Department of Paediatrics, KK Women's and Children's Hospital, Singapore. Electronic address: Terrence.Thomas@kkh.com.sg.
Terrence
T
Thomas
D000293:Adolescent; D001342:Autonomic Nervous System Diseases / Q000209:etiology*; D006801:Humans; D007031:Hypothalamus / Q000473:pathology*; D007040:Hypoventilation / Q000209:etiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D009765:Obesity / Q000150:complications* / Q000473:pathology*; D010487:Periaqueductal Gray / Q000473:pathology*
ROHHAD syndrome; autoimmune encephalitis; hypothalamus; periaqueductal gray matter