Making an objective diagnosis of tetanus—utility of a simple neurophysiological test

Abstract

Tetanus remains a significant cause of mortality especially in the developing world. Early diagnosis and institution of treatment is critical to prevent fatal complications. The diagnosis is made on clinical grounds, which may sometimes be difficult, especially in case of localised tetanus. Being able to diagnose tetanus objectively is invaluable in such cases. In this regard, masseter inhibitory reflex (MIR) is a simple neurophysiological test that can be performed at the bedside. Herein, we report a case of craniocervical tetanus that was objectively diagnosed using MIR and adequately treated.

The Myriad Presentations of Tetanus: Where Do You Look for Clinical Clues in an Intubated Highly Sedated Patient?

“…One of the investigative tools for confirming trismus is the masseter inhibitory reflex test, which typically reveals a loss of silent period on electromyography when the masseter is activated, resulting from central neuronal hyper‐excitability. However, it was not performed here because of unavailability, the patient's unstable condition, and the potential for false negatives from high doses of sedation, magnesium sulfate, or timing of the test, which has been reported to occur after 9 weeks of disease onset 12,13 . Differential diagnoses, including PERM, strychnine poisoning, and carpopedal spasm, can be distinguished based on initial symptoms and progression patterns (Table 2).…”

“…However, it was not performed here because of unavailability, the patient's unstable condition, and the potential for false negatives from high doses of sedation, magnesium sulfate, or timing of the test, which has been reported to occur after 9 weeks of disease onset. 12,13 Differential diagnoses, including PERM, strychnine poisoning, and carpopedal spasm, can be distinguished based on initial symptoms and progression patterns (Table 2). [14][15][16][17] A comprehensive review of clinical findings emphasizes the continuous Video 2.…”