Faculty Bibliography

Amlodipine is a potent vasodilator with a long half-life and delayed onset of action that is particularly concerning after an overdose. Vasodilation occurs through stimulation of nitric oxide release with increased cyclic guanosine monophosphate (cGMP) production. Methylene blue inhibits guanylate cyclase. This enzyme is responsible for the production of cGMP. Methylene blue also has the ability to scavenge nitric oxide, as well as inhibit nitric oxide synthase. We report the use of methylene blue for refractory shock in a patient with amlodipine toxicity

Metals such as iron and copper are critical to living organisms, whereas other metals such as lead and arsenic have no known biologic role. Any metals in large amounts may cause toxicity. Many metals cause pervasive systemic effects involving the nervous system, which can be subtle in some cases. Although challenging, the diagnosis and treatment of metal poisoning can be made based on history, physical examination, and the proper use of metal testing. This article focuses on the use, and misuse, of chelation in the diagnosis and management of metal intoxication

OBJECTIVES: In the treatment of acetaminophen toxicity, clinicians believe that N-acetylcysteine (NAC) artificially elevates prothrombin time (PT), potentially obscuring signs of liver damage. However, the effect of NAC on human blood coagulation remains unverified. The purpose of this study was to evaluate the effect of NAC on PT prolongation in human plasma. METHODS: The authors obtained blood samples from 33 volunteer subjects. The blood plasma samples were divided into four 1-mL aliquots. The first aliquot was used as a control. To three additional aliquots, varying amounts of NAC were added, maintaining constant volume with a maximum dilution of 0.5%. The four concentrations of NAC (control, 250, 500, or 1,000 mg/L) were incubated at 37 degrees C for 1 hour, and PT was measured. PT values were compared using fixed effects regression. RESULTS: Mean (+/- standard deviation [SD]) PT values for the control, 100, 500, and 1,000 mg/L NAC values were 13.9 (+/-1.01), 14.2 (+/-1.08), 15.5 (+/-1.21), and 17.4 (+/-1.72) seconds, respectively. At the 1,000 mg/L concentration, two PTs exceeded 22 seconds, and half exceeded 17 seconds. PT increased with NAC concentrations (fixed effects regression p < 0.001) in a dose-dependent manner. CONCLUSIONS: In this in vitro human model, NAC had a dose-dependent effect on PT

OBJECTIVE: Abrus precatorius is cultivated in many subtropical areas. The seeds exist in a variety of colors such as black, orange, and most commonly, glossy red. A black band is found at the end of the seed. The plant contains multiple pods which typically contain three to five Abrus seeds. The seeds contain abrin, which inhibits ribosomal function, halting protein synthesis and leading to cellular death. A unique aspect of this case is the use of the internet to order a potentially lethal poison as well as transmission of a picture to identify the seed. CASE REPORT: A 20-year-old man presented to the emergency department complaining of vomiting and watery diarrhea for 6-8 h prior to arrival. He denied any medication use, recent illness, travel, or changes in his diet. Initial vital signs were normal. The patient was diagnosed with viral gastroenteritis. During his evaluation, the patient admitted to feeling suicidal. While awaiting psychiatry evaluation, the patient's father arrived with a box of small hard red seeds, which he believed that his son ingested in a suicide attempt. The seeds could not be identified by the staff. A picture of the seeds was transmitted by e-mail to the New York City Poison Control Center, allowing their identification as A. precatorius. The patient was reinterviewed and admitted to chewing and swallowing 10 seeds. Given the potential toxicity of abrin, the patient was admitted to the intensive care unit. He continued to have frequent episodes of emesis as well as diarrhea. He gradually improved over 2 days. He admitted to ordering a box of Abrus seeds online from Asia after reading on the Internet about their use in suicide. He was eventually discharged for outpatient follow-up with no permanent sequelae. CONCLUSION: Abrin has an estimated human fatal dose of 0.1-1 mug/kg. Most cases of Abrus seed ingestions are unintentional and occur in children. Ingesting the intact seeds typically results in no clinical findings, as they pass through the gastrointestinal tract due to their hard shell. Abrin released during chewing is poorly absorbed systemically from the gastrointestinal tract. This causes the vomiting and diarrhea with resultant hypovolemia and electrolyte disturbances, which can be severe and life threatening, particularly in areas with less advanced health care systems. Management is primarily supportive