A Rare Case of Childhood Stiff Person Syndrome Associated With Pleuropulmonary Blastoma.
BACKGROUND
Stiff person syndrome is a rare autoimmune, neurological disorder characterized by progressive rigidity and episodic painful spasms, predominantly affecting the proximal limbs and axial muscles, and leading to progressive disability. We report the case of a child who developed symptoms compatible with stiff person syndrome during treatment for pleuropulmonary blastoma.


METHODS
A 3-year, 5-month-old girl was admitted for gradually worsening postural tremor, painful spasms, and generalized stiffness. Since the age of 3 years, she had been on adjuvant chemotherapy for pleuropulmonary blastoma before surgical resection. Brain magnetic resonance imaging and electroencephalographic findings were normal. Although serologic tests for autoimmune disease, including paraneoplastic antibodies and antiglutamic acid decarboxylase antibodies, were unremarkable, her findings were attributed to a paraneoplastic syndrome based on her clinical features and medical history. However, following the planned pulmonary lobectomy, her symptoms were paradoxically aggravated, with continuous motor unit potential at rest on electromyography, which occurs in stiff person syndrome. She gradually improved during postadjuvant chemotherapy with simultaneous immunotherapy including intravenous immunoglobulins and methylprednisolone, and she had recovered completely when evaluated at the 22-month follow-up visit after completion of her treatment for pleuropulmonary blastoma.


CONCLUSIONS
We present the first documented child with stiff person syndrome associated with pleuropulmonary blastoma. The marked clinical improvement following chemotherapy for pleuropulmonary blastoma was yet more proof of the pleuropulmonary blastoma-related stiff person syndrome. In children with a malignancy and stiff person syndrome, a paraneoplastic syndrome should be considered and the treatment for the malignancy must be undertaken.
Division of Pediatric Neurology, Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea.
Hyun-Ok
HO
Jun
Division of Pediatric Neurology, Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea.
Mi-Sun
MS
Yum
Division of Pediatric Neurology, Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea.
Eun-Hee
EH
Kim
Division of Pediatric Neurology, Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea.
Yun-Jeong
YJ
Lee
Division of Pediatric Hemato-oncology, Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea.
Jong-Jin
JJ
Seo
Division of Pediatric Neurology, Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea. Electronic address: tsko@amc.seoul.kr.
Tae-Sung
TS
Ko
D002675:Child, Preschool; D004576:Electromyography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging / Q000473:pathology; D020361:Paraneoplastic Syndromes, Nervous System / Q000209:etiology / Q000473:pathology / Q000503:physiopathology* / Q000628:therapy; D018202:Pulmonary Blastoma / Q000150:complications* / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D016750:Stiff-Person Syndrome / Q000209:etiology / Q000473:pathology / Q000503:physiopathology* / Q000628:therapy; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
paraneoplastic syndrome; pleuropulmonary blastoma; stiff man syndrome; stiff person syndrome