Peripheral nervous system manifestations of acute intermittent porphyria include what?

Peripheral nervous system manifestations of acute intermittent porphyria include what?

• A. Increased muscle strength
• B. Skeletal muscle weakness with risk of respiratory failure
• C. Nerve regeneration
• D. Peripheral neuropathy with paresthesias

Answer: (B)

In acute intermittent porphyria, the nervous system can be affected, but the peripheral nervous system involvement is primarily a motor neuropathy that can progressively weaken skeletal muscles, including the muscles needed for breathing. This makes respiratory failure a key and potentially life-threatening feature during an attack. While sensory symptoms like paresthesias can occur, the most clinically important peripheral nervous manifestation is the widespread skeletal muscle weakness that risks ventilatory failure. The other options don’t capture this dangerous motor progression; increased strength isn’t typical, nerve regeneration isn’t the hallmark acute finding, and while some sensory symptoms can be present, they don’t define the serious PNS involvement as clearly as respiratory-tract–impacting weakness does.

In acute intermittent porphyria, the nervous system can be affected, but the peripheral nervous system involvement is primarily a motor neuropathy that can progressively weaken skeletal muscles, including the muscles needed for breathing. This makes respiratory failure a key and potentially life-threatening feature during an attack. While sensory symptoms like paresthesias can occur, the most clinically important peripheral nervous manifestation is the widespread skeletal muscle weakness that risks ventilatory failure. The other options don’t capture this dangerous motor progression; increased strength isn’t typical, nerve regeneration isn’t the hallmark acute finding, and while some sensory symptoms can be present, they don’t define the serious PNS involvement as clearly as respiratory-tract–impacting weakness does.