UMEM Educational Pearls

Category: Toxicology

Title: Intermediate Syndrome

Keywords: organophosphates, intermediate syndrome (PubMed Search)

Posted: 9/6/2012 by Ellen Lemkin, MD, PharmD
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  • Exposure to organophosphates can lead to “intermediate syndrome.”
  • It is a syndrome characterized by weakness of neck flexors and proximal limbs, cranial nerve palsies, and respiratory muscle weakness, which can lead to respiratory paralysis.
  • It follows acute cholinergic syndrome and precedes a delayed neuropathy, thus it is an “intermediate syndrome,” typically developing 24-96 hours post exposure.
  • The pathophysiology of IMS remains unclear.
  • Serum cholinesterase levels and electrophysiological studies are helpful in confirming the diagnosis.
  • With supportive therapy, including artificial ventilation, complete recovery occurs within 5-18 days.