Spontaneous periodic hypothermia

Spontaneous Periodic Hypothermia is a rare medical condition characterized by the recurrent episodes of significant drops in body temperature without an apparent external cause. This condition is also known by other names such as Shapiro's syndrome after the physician who first described it, or familial spontaneous hypothermia. It is distinct from other forms of hypothermia that result from exposure to cold environments, inadequate thermal insulation, or certain medical conditions that impair thermoregulation.

Symptoms and Diagnosis

The primary symptom of spontaneous periodic hypothermia is the unexpected and unexplained onset of low body temperature, often below 35°C (95°F), which can be accompanied by shivering, dizziness, confusion, and in severe cases, hypotension and bradycardia. These episodes can last from hours to days and may recur at irregular intervals. Diagnosis is primarily clinical, based on the history of recurrent hypothermic episodes without external causes. Laboratory tests and imaging studies are typically used to rule out other conditions that could cause similar symptoms, such as hypothyroidism, Addison's disease, or sepsis.

Etiology

The exact cause of spontaneous periodic hypothermia remains largely unknown. However, it is believed to involve abnormalities in the hypothalamus, the part of the brain responsible for regulating body temperature. Some cases have been associated with agenesis of the corpus callosum, a condition where the structure connecting the two hemispheres of the brain is partially or completely absent. Genetic factors may also play a role, as some cases have been reported to occur in families.

Treatment

Treatment of spontaneous periodic hypothermia focuses on managing symptoms and preventing complications during episodes. This may involve passive or active rewarming techniques, depending on the severity of the hypothermia. In some cases, medications that affect the hypothalamus or the autonomic nervous system have been used to prevent or reduce the frequency of episodes. Due to the rarity of the condition, there is no standardized treatment protocol, and management is often tailored to the individual patient's needs.

Prognosis

The prognosis for individuals with spontaneous periodic hypothermia varies. While the condition can be life-threatening if not properly managed, with appropriate care, most individuals can lead relatively normal lives. However, the unpredictable nature of the episodes can pose challenges for affected individuals and their families.

See Also

• Hypothermia
• Thermoregulation
• Shapiro's syndrome