Differential Diagnosis for Thyroid Storm with Muscle Rigidity and Neck Hyperextension
- Single most likely diagnosis
- Thyrotoxic crisis: This condition is a life-threatening complication of untreated or undertreated hyperthyroidism, characterized by extreme symptoms of thyrotoxicosis, including muscle rigidity, which can lead to neck hyperextension. The presentation of thyroid storm, muscle rigidity, and neck hyperextension strongly suggests this diagnosis.
- Other Likely diagnoses
- Malignant hyperthermia: Although rare, this condition can be triggered by certain anesthetics and presents with muscle rigidity, hyperthermia, and can lead to a hyperextended neck due to the rigidity. It's a medical emergency that requires immediate attention.
- Neuroleptic malignant syndrome (NMS): NMS is a life-threatening neurological disorder caused by an adverse reaction to neuroleptic or antipsychotic medication. It presents with muscle rigidity, fever, and altered mental status, which could potentially lead to a hyperextended neck.
- Do Not Miss diagnoses
- Tetanus: Although less common in areas with good vaccination coverage, tetanus infection can cause severe muscle rigidity (including the neck muscles), leading to a condition known as opisthotonus, where the body arches backward. Missing this diagnosis could be fatal due to respiratory failure.
- Strychnine poisoning: This is a highly toxic substance that can cause muscle convulsions, leading to extreme rigidity and potentially a hyperextended neck. It's crucial to consider in cases of unexplained muscle rigidity.
- Rare diagnoses
- Stiff person syndrome: A rare neurological disorder characterized by progressive stiffness and rigidity of the muscles, which could potentially lead to an abnormal posture, including neck hyperextension. However, it's less likely to present acutely like in the scenario described.
- Hypocalcemia-induced tetany: Severe hypocalcemia can cause muscle cramps, spasms, and rigidity. While it's more commonly associated with carpopedal spasm, in rare cases, it could contribute to generalized rigidity, including the neck muscles.