A teenager brought to the emergency room is noted to be hyperventilating. Blood gas studies demonstrate both a respiratory alkalosis and a metabolic acidosis. This presentation is most suggestive of poisoning with which of the following agents?

It is woh learning the presentations of the common poisons listed in the answer choices, because a timely diagnosis can sometimes save a patient's life. The presentation of the teenager in the question is typical for salicylate poisoning, including poisoning with aspirin. Fatalities are typically due to dehydration and hypokalemia. In contrast to the acute toxicity of salicylates, acetaminophen poisoning produces nausea, vomiting, abdominal pain, and shock in some cases; it can cause irreversible hepatic failure (which can be prevented or ameliorated by administration of N-acetylcysteine) 2-6 days after ingestion. Carbon monoxide causes hypoxia, and a cherry red coloration of the lips and mucous membranes may be evident. Lead and mercury poisoning are both usually seen in their chronic forms, although mercury ingestion can produce an acute toxicity with renal tubular necrosis and necrosis of gastrointestinal epithelium. Chronic lead poisoning can cause anemia (with basophilic stippling of RBCs), neuropathy, and abdominal pain. Ref: Corbridge T., Murray P., Mokhlesi B. (2005). Chapter 102. Toxicology in Adults. In J.B. Hall, G.A. Schmidt, L.D. Wood (Eds), Principles of Critical Care, 3e.