Procedure That Blocks Some Neck Nerves May Help Control EGPA
Stellate ganglion block, a procedure where a pain-relieving medicine is injected into the neck to block certain nerves, might be a successful therapeutic approach for eosinophilic granulomatosis with polyangiitis (EGPA), a recent case study suggests.
The procedure helped control symptoms and lower corticosteroid doses, which are associated with detrimental side effects when used long term.
EGPA is a form of ANCA-associated vasculitis (AAV) where immune cells called eosinophils mistakenly attack small blood vessels in the lungs and respiratory tract, leading to asthma-like symptoms.
Glucocorticoids alone or in combination with immunosuppressants are a standard of care for treating EGPA. While most EGPA patients achieve remission with this type of treatment, they can still have frequent relapses and continue to rely on high-dose glucocorticoids. Long-term use is associated with significant side effects, however, underscoring the need for new therapies.
Researchers at the Beijing Chaoyang Hospital, China, describe a female patient with hard-to-treat EGPA and asthma who successfully responded to stellate ganglion block, which consists of injecting a pain-reliving medicine to the stellate ganglion nerves in the neck. This is often used to ease pain in the head, neck, chest or arms, but has also been shown to be effective for asthma.
The 32-year-old woman went to the hospital after having wheezing, bruising, and numbness in several fingers that was getting worse, as well as prolonged abdominal pain for about six months.
She had bronchial asthma for five years, for which she was being treated with inhaled corticosteroids.
The woman had an abnormally high number of white blood cells, especially eosinophils, along with high levels of an inflammatory marker called C-reactive protein. She also had high levels of rheumatoid factor, an autoantibody primarily characteristic of rheumatoid arthritis, but also seen in certain EGPA patients.
A chest CT scan showed a patchy or opaque area in the right lower lung.
The patient was diagnosed with EGPA and began treatment with the glucocorticoid prednisone acetate (30 mg) and the immunosuppressive medication cyclophosphamide (50 mg), both given orally.
Symptoms resolved quickly and eosinophil levels normalized. After four weeks, prednisone acetate was reduced to 27.5 mg and then to 25 mg. Within two weeks, however, the patient had a relapse of respiratory, digestive, and neurological symptoms.
She received another corticosteroid, betamethasone, given as an intramuscular injection, but her symptoms resumed after a week.
The woman then underwent stellate ganglion block, which was proposed given its effectiveness in treating asthma and other conditions. The procedure was conducted under ultrasound guidance. She immediately developed Horner’s syndrome, which can arise after stellate ganglion block and is caused by a disruption in the nerve pathway carrying signals from the brain to one side of the face. Horner’s syndrome is characterized by eyelid droopiness, decreased pupil size, and reduced sweating on the affected side.
All her symptoms, including wheezing, abdominal pain, and finger numbness, were resolved after stellate ganglion block. The procedure was repeated every two days, alternating between the left and the right side of the neck, and stopped after seven interventions.
Prednisone acetate was successfully tapered to 22.5 mg daily with no signs of relapse and no need for inhaled corticosteroids.
Her symptoms recurred again after an emotional event, but inhaled corticosteroids controlled her asthma. A second course of stellate ganglion block once more led to symptom relief.
Prednisone acetate was reduced to 10 mg/day, and cyclophosphamide was maintained at a dose of 50 mg for three months.
Overall, “our case suggests that ultrasound-guided [stellate ganglion block] may represent a simple and safe method to relieve symptoms and impede disease progression in EGPA patients, and may lead to wider usage of the technique in immune-linked disorders,” the researchers wrote.