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Extreme startle and photomyoclonic response in severe hypocalcaemia
Marcello Moccia1, Roberto Erro2, Elvira Nicolella1
1Epilepsy Centre, Department of Neuroscience, Reproductive Science and Odontostomatology, Federico II University, Naples, Italy.
Summary
Severe hypocalcemia can cause an exaggerated startle reflex and photomyoclonic responses, mimicking seizures. This case highlights the diagnostic challenge in differentiating epileptic from non-epileptic events.
Area of Science:
- Neurology
- Clinical Electrophysiology
- Endocrinology
Background:
- Distinguishing between epileptic and non-epileptic seizures is crucial for accurate diagnosis and treatment.
- An exaggerated startle reflex and photomyoclonic responses are neurological signs that can be associated with various conditions.
Observation:
- A 62-year-old woman presented with suspected tonic-clonic seizures.
- Clinical examination revealed an exaggerated startle reflex.
- Electroencephalography (EEG) demonstrated a photomyoclonic response, and blood tests confirmed severe hypocalcemia.
Findings:
- This case presents the first documented instance of an exaggerated startle reflex and extreme photomyoclonic response directly caused by severe hypocalcemia.
- The findings underscore the importance of metabolic screening in patients with unexplained neurological phenomena.
Implications:
- This report expands the differential diagnosis for exaggerated startle reflexes and photomyoclonic responses.
- It emphasizes the need to consider electrolyte imbalances, particularly hypocalcemia, in the evaluation of seizure-like activity.
- Further research may explore the precise mechanisms linking hypocalcemia to these specific neurological manifestations.
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