Woman Diagnosed With Rare Condition Behind Decades of Dizziness and Falling

A 50-year-old woman in New York spent five years losing the ability to bend her legs, walk, or sit up before doctors finally nailed down her diagnosis: stiff person syndrome (SPS), a disorder that strikes just one or two in a million people each year.

The woman first felt discomfort in her knees and lower back about five years before she sought care. By the time she reached the hospital, she could not get out of bed, sit up, or turn to either side. Her symptoms included chronic lower-back pain, recurring fever and chills, and unexplained weight loss of more than 30 pounds (14 kilograms).

Doctors initially prescribed ibuprofen and physical therapy after her first hospital visit. Those treatments did nothing to stop the stiffness or pain. When she returned a month later, her condition had worsened dramatically.

The Blood Test That Pointed To SPS

Blood tests showed that the woman’s white blood cell count was normal, ruling out an infection. She also lacked antibodies linked to rheumatoid arthritis, HIV, Lyme disease, or Sjögren’s disease — all conditions that can cause joint stiffness and pain.

But one test result stood out. Doctors found high levels of antibodies that block the enzyme glutamic acid decarboxylase (GAD). Elevated GAD antibodies appear in up to 80% of people with SPS.

These antibodies prevent GAD from producing GABA, a chemical messenger that acts like a brake on nerve cell activity. Without enough GABA, nerve cells that control muscle contraction go into overdrive, triggering painful spasms and preventing muscles from relaxing normally.

The Treatment That Worked

There is no cure for SPS, but medication can slow the disease’s progression and manage symptoms. The woman received intravenous immune globulin, rituximab, prednisone, gabapentin, and diazepam.

Within a few days, her condition improved. She could turn in her bed unassisted, flex her left hip and knee fully, and flex her right hip fully and right knee with assistance to 110 degrees. She could stand with assistance.

At a three-month checkup after being discharged, she could stand unassisted and walk using a rolling walker. Her doctors started reducing her steroid dose but kept her on diazepam and gabapentin, plus a monthly dose of immune globulin and a maintenance dose of rituxab every six months.

Why The Diagnosis Took So Long

SPS is difficult to spot because its symptoms can look like other illnesses. The condition is often misidentified as psychiatric disorders, Parkinson’s disease, multiple sclerosis, or dystonia, a neurological disorder that causes muscle spasms.

Diagnosis typically takes about seven years from symptom onset, according to the Stiff Person Syndrome Research Foundation. It most commonly affects people ages 40 to 50, though it can appear in older adults and children. Women are affected about twice as often as men, according to the National Institute of Neurological Disorders and Stroke.

Just one or two in a million people are thought to be affected by SPS each year, although recent estimates suggest that number may be higher. The condition’s rarity and slow symptom development make it challenging for health professionals to recognize and treat.

Its mechanisms and progression are “incompletely understood,” the case report authors noted.

“Prior to discharge, the patient could turn in her bed unassisted, could flex her left hip and knee fully, could flex [her] right hip fully and right knee with assistance to 110 degrees, and could stand with assistance.”

What This Case Shows

This woman’s story is a reminder that getting the right diagnosis can take years of frustration. Her first hospital visit produced useful test results but failed to identify the underlying problem.

Her case is also unusual in how quickly her symptoms responded to the right treatment. Within a few days of starting treatment, she could move again.

SPS remains a rare and poorly understood condition. Its symptoms can mimic several other illnesses, and its diagnosis often comes late.

The woman’s case offers hope that even after years of suffering, the right treatment can bring relief.

Source material: “Woman's 5-year struggle with balance and walking was caused by a 'one-in-a-million' disorder,” Live Science.

diagnosis · medical case study · neurology · rare diseases · stiff person syndrome