Relief of dantrolene suggests that the fever was due to malignant hyperthermia?

Malignant hyperthermia (MH) is a rare but potentially fatal condition that can occur in susceptible individuals when they are exposed to certain triggering agents, such as certain inhaled anesthetics and succinylcholine. MH is characterized by a rapid increase in body temperature, muscle rigidity, and a breakdown of muscle tissue, which can lead to kidney failure, heart problems, and even death if not treated promptly.

Dantrolene is a muscle relaxant that is used to treat MH. It works by blocking the release of calcium from the sarcoplasmic reticulum, which is the cell's calcium storage compartment. This helps to reduce muscle contractions and lower body temperature.

If a patient's fever resolves after being given dantrolene, it suggests that the fever was likely due to MH. This is because dantrolene is specific for MH and does not typically relieve other types of fevers.

However, it's important to note that other conditions can also cause a rapid increase in body temperature and muscle rigidity, such as neuroleptic malignant syndrome (NMS) and serotonin syndrome. Therefore, a thorough medical evaluation is necessary to determine the exact cause of the fever and the appropriate treatment.