Critical Kennedy’s disease with Guillain-Barré syndrome and respiratory failure

Rationale: Spinal and bulbar muscular atrophy (SBMA, Kennedy disease) is a rare X-linked progressive neurodegenerative disorder. Evidence on the intensive care management of severe SBMA with acute decompensation remains scarce, and superimposed treatable immune-mediated neuropathies are often overlooked in such clinical scenarios. Patient concerns: A 61-year-old man with a 35-year history of progressive limb weakness and 3 months of worsening dysphagia was transferred to our hospital for acute respiratory failure. He had developed progressive dyspnea, ineffective cough, and secretion retention over 15 days, and had been intubated for hypoxemic respiratory failure at the referring facility. Diagnoses: Genetic testing confirmed SBMA as the underlying diagnosis, accounting for the patient’s chronic progressive weakness, bulbar dysfunction, and chronic neurogenic electrophysiologic changes. Superimposed probable Guillain–Barré syndrome was suspected based on acute monophasic deterioration, generalized areflexia, sensorimotor axonal neuropathy, and positive anti-ganglioside antibodies, though diagnostic certainty was limited by normal cerebrospinal fluid protein and confounding chronic SBMA pathology. Concurrent conditions included pneumonia, acute segmental pulmonary embolism, and acute respiratory failure. Interventions: Multidisciplinary management was delivered, including invasive respiratory support, targeted antimicrobial therapy, therapeutic anticoagulation, aggressive bronchoscopic airway clearance, and structured pulmonary and neuromuscular rehabilitation. Four cycles of therapeutic plasma exchange were administered given ongoing suspicion of immune-mediated polyradiculoneuropathy. Outcomes: Oxygenation and muscle strength improved gradually with combined interventions, and no single treatment could be identified as the sole contributor. The patient experienced extubation failure on hospital day 18 due to persistent airway protection deficits, and underwent tracheostomy on day 26. He was successfully weaned from invasive ventilation and discharged to a rehabilitation facility on hospital day 44. Lessons: Acute neurological deterioration in patients with SBMA should prompt evaluation for superimposed, potentially treatable neuromuscular disorders, rather than being attributed exclusively to baseline disease progression. Integrated multidisciplinary care is essential to optimize outcomes in severe SBMA complicated by acute respiratory decompensation.