Analysis of clinical challenges and prognostic risk factors for 195 cases of iatrogenic botulism in China

Improper use of botulinum neurotoxin may result in poisoning. This study aimed to investigate the causes, characteristics, and risk factors of iatrogenic botulism incidents in China. Patients diagnosed with iatrogenic botulism who presented to the emergency department of the Second Hospital of Hebei Medical University between June and July 2024 were included. We assessed baseline demographics, clinical symptoms, disease grade, and botulinum toxin type A-related variables. Multivariate regression analysis was used to identify independent risk factors influencing the 30-day prognosis. A total of 195 patients were included in the study, with a median age of 38 years (IQR: 33-47 years) and a male-to-female ratio of 1:38. Blurred vision was the most common early feature (82.1%), followed by dizziness and ptosis (75.9%), fatigue (65.1%), and dysarthria (63.1%). The most frequently observed complications were acute gastroenteritis (9.7%), followed by aspiration pneumonia (7.2%). Fifty-one patients experienced severe poisoning with early ocular, facial, limb muscle, and respiratory muscle involvement. Thirty-two patients (16.4%) required mechanical ventilation. The median latent period was 3 days (IQR: 2-4 days), with a median interval of 7 h (IQR: 4-10 h) observed between symptom onset and antitoxin administration. The median duration of hospitalization was 6 days (IQR: 4-8 days). Adverse reactions to the antitoxin included serum sickness in 11 patients and allergic reactions in 20 patients. Based on the presence or absence of clinical signs 30 days post-discharge, we categorized the cohort into good and poor prognostic groups; 87 patients (44.6%) had a poor prognosis. Independent risk factors for a poor prognosis included a latent period ≤3 days, increased time from onset of features to antitoxin treatment, longer hospital duration, disease severity, and need for mechanical ventilation. Iatrogenic botulism frequently leads to severe outcomes due to delayed diagnosis and intervention. We identified a disease severity grading system alongside additional risk factors to predict patient prognosis. Our study underscores the critical importance of early recognition and timely treatment of iatrogenic botulism. Clinicians should implement prompt treatment to mitigate disease progression.