Differential Diagnosis of Tetanus
- Single most likely diagnosis
- Strychnine poisoning: This condition presents with similar symptoms to tetanus, including muscle stiffness, rigidity, and spasms, due to the inhibition of glycine, an inhibitory neurotransmitter, which can mimic the effects of tetanus toxin on the nervous system.
- Other Likely diagnoses
- Dystonic reactions: These can be caused by certain medications, such as antipsychotics and antiemetics, and may present with acute onset of muscle spasms and rigidity, similar to tetanus.
- Hypocalcemia: Low calcium levels can cause muscle cramps, spasms, and tetany, which might be confused with tetanus, especially in the early stages.
- Rabies: In its later stages, rabies can cause hydrophobia, which may lead to spasms of the laryngeal and pharyngeal muscles, potentially mimicking the spasms seen in tetanus.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Botulism: Although botulism typically presents with flaccid paralysis, in its early stages, it can cause symptoms that might be mistaken for tetanus, such as muscle weakness and cranial nerve palsies. Missing this diagnosis could be fatal due to the risk of respiratory failure.
- Meningitis: Inflammation of the meninges can cause stiffness and rigidity, which might be confused with tetanus. Early diagnosis and treatment of meningitis are crucial to prevent severe complications and death.
- Rare diagnoses
- Tetany due to hyperventilation: Hyperventilation can lead to respiratory alkalosis, causing tetany (involuntary muscle contraction) due to the decrease in ionized calcium. While not as severe as tetanus, it can present with similar symptoms and is worth considering in the differential diagnosis.
- Neuromyelitis optica (Devic's disease): This rare autoimmune disorder can cause muscle spasms and stiffness, among other neurological symptoms, and although it is much less common than tetanus, it should be considered in patients with atypical presentations or lack of response to tetanus treatment.