A Case Report of Familial Episodic Pain Syndrome Type 3 in a 5-Year-Old Boy

Medical history summary: The child has suffered from episodic joint pain in the lower extremities since childhood, with occurrences ranging from 1 to 3 times daily, predominantly during rainy, cold, and humid weather, as well as in the afternoons and evenings. Symptoms and signs: The primary manifestation is episodic pain in the distal extremities, predominantly in the lower limbs, knees, and ankles. Occasionally, the pain may ascend to the elbows, wrists, and palms, and may occasionally affect the proximal extremities and waist. Diagnostic methods: Nerve biopsy and related pathological examinations, along with whole exome sequencing, are helpful for diagnosis, particularly the detection of variants in the SCN11A gene. Treatment approaches: (1) Pharmacotherapy: Sodium channel blockers and nonsteroidal anti-inflammatory drugs such as ibuprofen and naproxen can alleviate pain. (2) Neuromodulation techniques: Techniques such as transcranial magnetic stimulation (TMS) and spinal cord stimulation (SCS) can be employed to improve symptoms. (3) Psychotherapy: Cognitive-behavioral therapy (CBT), relaxation training, or psychological counseling can enhance the patient’s coping abilities. Clinical outcome: Pain relief can be achieved with analgesic medication in children, and pain symptoms generally persist until adulthood, gradually diminishing or even disappearing. Patients can reduce the frequency of episodes by staying warm and avoiding cold and damp conditions.