What are the key clinical features that differentiate thyroid storm from other hyperthyroid crises?

Thyroid storm is a severe, life-threatening exacerbation of hyperthyroidism, distinguished from other hyperthyroid crises by profound systemic decompensation ¹, (Akamizu, 2012). While hyperthyroidism itself involves symptoms such as palpitations, weight loss, and anxiety, thyroid storm represents a decompensated state with multi-organ involvement (Akamizu, 2012).

The key clinical features that differentiate thyroid storm include:

• Central Nervous System (CNS) Dysfunction: This is a hallmark feature, ranging from agitation and delirium to psychosis, seizures, and coma (Akamizu, 2012). These severe neurological manifestations are typically absent or mild in uncomplicated hyperthyroidism.
• Cardiovascular Dysfunction: Patients often present with severe tachycardia (which may be disproportionate to fever), arrhythmias (such as atrial fibrillation), and signs of heart failure (Akamizu, 2012). While palpitations are common in hyperthyroidism, the severity and presence of heart failure are differentiating factors.
• Gastrointestinal-Hepatic Dysfunction: More prominent and severe symptoms include nausea, vomiting, diarrhoea, abdominal pain, and jaundice (Akamizu, 2012).
• Thermoregulatory Dysfunction: A high fever, often exceeding 38.5°C, is characteristic and may be out of proportion to other symptoms (Akamizu, 2012).
• Precipitating Event: Thyroid storm is frequently triggered by an acute event, such as infection, surgery, trauma, or the abrupt discontinuation of antithyroid medication in a patient with pre-existing hyperthyroidism (Akamizu, 2012).

The diagnosis of thyroid storm is primarily clinical, often supported by scoring systems like the Burch-Wartofsky Point Scale, which quantifies the severity of these systemic manifestations (Akamizu, 2012). NICE guidelines highlight thyroid storm as a rare but urgent complication requiring immediate hospital admission ¹.