Acute Respiratory Failure in a Patient with Stiff-Person Syndrome.

BACKGROUND: Stiff-person syndrome (SPS) is a rare disorder characterized by progressive muscle stiffness, rigidity, and spasms involving the axial muscles. Acute respiratory distress has rarely been reported in this condition.

METHODS: We report a case of a 49-year-old woman with autoimmune SPS diagnosed during an episode of acute respiratory failure secondary to repetitive episodes of apnea, requiring intensive care.

RESULTS: Acute respiratory failure manifesting with apneic episodes is a life-threatening and unpredictable complication of SPS. Its pathophysiology is not well known. The two suggested mechanisms are as follows: (1) apnea due to muscle rigidity and paroxysmal muscle spasms, and (2) paroxysmal autonomic hyperactivity. Sudden and unexpected deaths have been reported in SPS, and all described cases have been associated with apnea. Thus, the onset of apnea during SPS should be considered a criterion of high severity and should lead to intensive care unit (ICU) admission for continuous monitoring. In patients with severe disease who are unresponsive to symptomatic treatment with benzodiazepines and baclofen, or in patients with life-threatening complications, early immunotherapy by intravenous immunoglobulins should be considered.

CONCLUSION: Onset of apneas during SPS should be considered as a signal of possible progression toward acute respiratory failure and sudden death, and should lead to ICU admission for continuous monitoring. Early immunotherapy should be started in such situations, including intravenous immunoglobulins as the first-line treatment.