Rust developer Andrew Gallant describes his anti-NMDA receptor encephalitis diagnosis

Andrew Gallant, the Rust developer behind the ripgrep search tool, has published a short account of being diagnosed with anti-NMDA receptor encephalitis — an autoimmune disorder in which the body's antibodies attack the brain and cause inflammation.

The illness began with flu-like symptoms: a racing heart, night sweats, chills and trouble sleeping, but no congestion or cough. With them came a deep anxiety and panic attacks he had never experienced in 38 years, with no obvious trigger in his life or biological explanation at the time.

From jaw pain to psychosis

Over the following weeks the physical symptoms progressed to chronic jaw pain that made eating very difficult, and to balance problems: a man who had once juggled three balls could no longer catch a ball lobbed to him by his five-year-old son. The psychological symptoms were worse — suicidal ideation and psychosis, specifically delusions and auditory hallucinations.

The balance problems led to a fall in which he hit his head, and he and his wife decided he could not be safe at home. His first emergency room visit cleared him physically and sent him to an in-patient psychiatric hospital — a move he says he welcomed, because his symptoms had gone beyond what the family could manage.

Getting the right diagnosis

Anti-NMDA receptor encephalitis is commonly misdiagnosed as generalised anxiety disorder or schizophrenia. Because he had been cleared physically, leaving the psychiatric facility to see a neurologist proved difficult — the point, he writes, where the health care system let him down. A lucky connection with someone who happened to be a doctor got him out and into the neurology department at Brigham and Women's Hospital in Boston.

He spent almost a month in and out of that hospital, undergoing several MRIs, a lumbar puncture, EEGs and many more tests. An MRI revealed a lesion in his brain. Before the diagnosis was known he was already receiving intravenous immunoglobulin (IVIG) and methylprednisolone — what he now sees as a life-saving treatment protocol. Confirmation came later: the definitive test is a positive antibody test in cerebrospinal fluid, and results typically take a couple of weeks.

Prognosis and the CIELO trial

By the time the official diagnosis arrived, the IVIG and steroids had taken effect and he was feeling much better, though not back to normal. He is tapering off steroids and off medications prescribed for psychiatric symptoms before encephalitis was identified as the cause, and has enrolled in the CIELO clinical trial, which is testing satralizumab in treating anti-NMDA receptor encephalitis.

Autoimmune disorders have no known cure, but the prognosis for this form of encephalitis is very good. Gallant says his doctors told him it was caught early — despite the early detour into a psychiatric hospital — which is linked to better long-term outcomes, and that his recovery is exceeding his own expectations.

Gallant calls the episode the worst experience of his life and thanks his wife, Kaitlyn Brady, and his employer, Charlie Marsh, for their support.