Severe Headache in Primary Sjögren's Syndrome Responded to Rituximab

Primary Sjögren syndrome (pSS) is an immune systemic disease, that may affect the central nervous system. A severe headache unresponsive to treatment is the headache which is persistently nonresponsive to narcotic analgesics.

A 48-year-old woman with a 10-year history of pSS was seen in January 2021, complaining of a headache one week previously. The headache was characterised by a dull persistent pressing intensity and was not responding to paracetamol, NSAIDs or codeine. She had no previous history, nor family history. Physical examination revealed bilateral parotid glands enlargement. Laboratory tests showed anaemia, and elevated levels of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), with positive anti-La and anti-Ro antibodies. She was given topical treatment and different doses of Predlone, in addition to methotrexate10 mg/week. She had received three pulses of methylprednisolone and was started on azathioprine with a mild response to the headaches, so she received two initial IV doses of rituximab 375 mg/m², then every 2 weeks, with a clinical and laboratory response. Two years later, she had no headache.

Headache that may presented in pSS are tension headaches, migraines and cluster headaches. The therapy is disease-modifying antirheumatic drugs, hydroxychloroquine, glucocorticoids and biotherapeutics. Rituximab is used in the treatment of some patients with pSS, especially where it can affect systemic symptoms.

Rituximab treatment may be an option for severe headache in patients with pSS. The mechanism is unknown but may be due to depletion of brain auto-reactive B cells. Further research is needed.

An unresponsive headache in a patient with primary Sjögren's syndrome treated with tryptophan, opioids and NSAIDs responded successfully to B-cell depletion with rituximab.We hypothesise that brain-autoreactive B cells were involved in the pathogenesis of the headache.