A Case of Botulism After Intramuscular Injection of Botulinum Toxin
Marc Daou1, Aya Shnawa1, Valeria Ariza Hutchinson1, Ivanna Joseph1, Aleksandra Yakhkind1
1Neurology, Tufts Medical Center
Objective:

Case report

Background:
Botulinum toxin is a neurotoxin produced by the bacterium Clostridium botulinum that can result in severe flaccid paralysis. Although its therapeutic applications are well-known, botulism can occur after unintentional intramuscular injections of the toxin. Early diagnosis and management are essential as this condition can be life-threatening when untreated.
Design/Methods:

N/A

Results:

A 36-year-old female with no significant past medical history presented with 1-week history of generalized weakness. She had botulinum toxin injections into her cheeks and forehead two days prior to symptoms onset. The toxin was obtained off the internet and neither its quality nor the credentials of the administering individual could be verified. She also noticed difficulty chewing and swallowing both liquids and solids limiting her oral intake, followed by worsening lethargy and weakness. On physical exam, she had bilateral ptosis, difficulty resisting eye-opening, dysarthria, and symmetric generalized weakness. Reflexes were present and symmetric, and sensation intact to light touch. Investigations including anti-acetylcholine receptor, muscle-specific kinase, lipoprotein receptor-related protein-4 antibodies, TSH, MRI brain, and EMG were unremarkable. However, her respiratory status worsened requiring non-invasive mechanical ventilation, and she was empirically treated with pyridostigmine. The CDC was contacted, and Botulism antitoxin obtained and administered.  Her symptoms then improved significantly, and she was discharged without residual deficits.

Conclusions:

Botulism is a rare but potentially fatal neuroparalytic disease caused by botulinum toxin. It usually occurs after ingestion of contaminated food but can be seen with improper administration of botulinum toxin. EMG is expected to show decremented response to repetitive low frequency and facilitated response to repetitive high frequency nerve stimulation with low compound muscle action potential. This was not the case of our patient whose study was confounded by pyridostigmine's administration. This case highlights the importance of early diagnosis and treatment with antitoxin as botulism can rapidly progress to respiratory failure if untreated.

10.1212/WNL.0000000000204127