Rao AK, et al. - In this study, researchers aimed to describe the reported spectrum of clinical findings among patients with botulism aged >12 months in the United States during 2002–2015. This analysis revealed that among patients with botulism, classic symptoms and signs were common, however, the features considered atypical were reported by some physicians. As illustrated by the broad range of illnesses on physician differentials, the diagnosis could be challenging.

Methods

• Clinical findings reported by physicians treating suspected cases of botulism nationwide were collected by the Centers for Disease Control and Prevention.
• Symptoms and signs, and neuroimaging and cerebrospinal fluid (CSF) results were analyzed.
• For this study, a case was defined as illness compatible with botulism with laboratory confirmation or epidemiologic link to a confirmed case, and presence or absence of at least 1 sign or symptom recorded.
• Researchers evaluated physicians’ differential diagnoses.

Results

• Clinical information of 332 botulism cases was evaluated; variable data quality and completeness was observed.
• Majority of the patients had no fever (99%), descending paralysis (93%), no mental status change (91%), at least 1 ocular weakness finding (84%), and neuroimaging without acute changes (82%).
• Researchers observed paresthesias (17%), elevated CSF protein level (13%), and other features sometimes considered indicative of alternative diagnoses in some patients.
• Atypical findings (eg, at least 1 cranial nerve finding that was unilateral or ascending paralysis) were reported in 5 of 71 (7%) cases with sufficient information.
• Physicians reported Guillain-Barré syndrome (99 cases) and myasthenia gravis (76 cases) and, rarely, gastrointestinal-related illness (5 cases), multiple sclerosis (3 cases), sepsis (3 cases), and Lyme disease (2 cases) on their differential diagnosis .