title: Secondary non-response due to antibody formation in a child after three injections of botulinum toxin B into the salivary glands.
abstract: Botulinum toxin (BTX) offers a new treatment option to reduce drooling in adults and children. Antibody formation against BTX is known to be one reason for clinical secondary non-response to this treatment. This is a case report on the development of secondary non-response to BTX type B (BTX-B) in a 15-year-old male, with bilateral dyskinetic cerebral palsy (Gross Motor Function Classification System Level IV) with additional learning disability* and microcephaly, treated for the indication of drooling. After three successful treatment sessions, the fourth and fifth injections showed no clinical response. This was associated with the presence of antibodies against BTX-B as determined using the mouse diaphragm assay. Thus, formation of neutralizing antibodies against BTX-B appears to be an important issue, not only in patients treated for cervical dystonia but also in children treated for drooling. Subsequent injections with an adequate dose of BTX type A (BTX-A) did not show any clinical response either, although no antibodies to BTX-A were detected. Besides the unanswered questions of dosing and distribution, a second possible explanation could be that BTX-B gave rise to non-neutralizing antibodies that cross-react with BTX-A. The resulting immune complexes could be taken up by phagocytes and, thereby, impede clinical response.
authors.affiliation: Dr von Hauner's Children's Hospital, University of Munich, Munich, Germany. steffen.berweck@med.uni-muenchen.de
authors.forename: Steffen
authors.initials: S
authors.lastname: Berweck
authors.forename: A Sebastian
authors.initials: AS
authors.lastname: Schroeder
authors.forename: Seung-Hee
authors.initials: SH
authors.lastname: Lee
authors.forename: Hans
authors.initials: H
authors.lastname: Bigalke
authors.forename: Florian
authors.initials: F
authors.lastname: Heinen
mesh_terms: D000293:Adolescent; D000917:Antibody Formation / Q000187:drug effects*; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D002547:Cerebral Palsy / Q000150:complications / Q000503:physiopathology; D004334:Drug Administration Schedule; D005500:Follow-Up Studies; D006801:Humans; D007859:Learning Disabilities / Q000150:complications; D008297:Male; D009069:Movement Disorders / Q000150:complications / Q000503:physiopathology; D009465:Neuromuscular Agents / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D012008:Recurrence; D012469:Salivary Glands / Q000187:drug effects* / Q000503:physiopathology; D012720:Severity of Illness Index; D012798:Sialorrhea / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A