Buckthorn Berry Intoxication

Epidemiology

  • Due to ingestion of fruit from the flowering shrub/small tree, Karwinskia humboldtiana (aka Coyotillio or Humboldt Coyotillo) in the buckthorn family (Rhamnaceae)
  • Geographic Distribution: Karwinskia humboldtiana plant is found in the southwestern US and Mexico
  • Prevalence in Humans: children are the most commonly affected
  • Prevalence in Animals: cattle and goats are the most commonly affected
    • Cattle are the most susceptible
    • In animals, disease is called “Limberleg”: presents with incoordination and ataxia

Physiology

  • Exposure: ingestion of buckthorn fruit (Karwinskia humboldtiana)
    • Severity of toxicity is proportionate to the amount of fruit ingested
  • Toxic Substance: Peroxisomicine (aka T-514, Tullidol)
  • Mechanism
    • Peroxisomicine destroys peroxisomes -> generation of free radicals -> lipoperoxidation of cell membranes -> cell death
    • Peroxisomicine specifically targets thick, distal nerve segments, resulting in demyelination
    • Histologically, there is widening of the periaxonal space and a redistribution of axonal organelles to a marginal position
    • Eventually, axons undergo wallerian degeneration

Clinical

Neurologic Adverse Effects

  • Demyelinating Peripheral Neuropathy (see Peripheral Neuropathy)
    • Diagnosis
      • LP: normal CSF
    • Clinical
      • Latency of Onset: 5-20 days after ingetsion
      • Course: rapid progression
      • Motor Findings
        • Lower>upper extremity weakness
        • May progress to severe quadriparesis with bulbar and respiartory involvement
        • Cranial Nerves: normal
      • Sensory Findings: mild and distal
      • Pathology
        • Segmental demyelination ± axonal swelling and loss
        • Experimental: axonal loss (motor) is more prominent with systemic experimental administration of toxin
        • Occasional degeneration of skeletal muscle fibers
    • Treatment: supportive care
    • Prognosis: may improve spontaneously over 3-12 mo
  • Muscle Cramps

Pulmonary Adverse Effects

Other Adverse Effects

  • Diarrhea (see Diarrhea)
  • Fever (see Fever)
  • Headache (see Headache)
  • Hepatic Necrosis
  • Degeneration of Cardiac Muscle Fibers: occasional
  • Micturition Difficulty/Urinary Retention

References

  • http://neuromuscular.wustl.edu/nother/toxic.htm
  • Intoxication with buckthorn (Karwinskia humboldtiana): report of three siblings. Pediatr Dev Pathol. 2007 Jan-Feb;10(1):66-8 [MEDLINE]
  • Karwinskia humboldtiana (buckthorn) fruit causes central nervous system damage during chronic intoxication in the rat. Toxicon. 2009 May;53(6):645-51 [MEDLINE]