Sunder Lal, 28 year old farmer is found convulsing in the farm. Heart rate is 100/min and blood pressure is 180/110 mm Hg. Diarrhea, sweating and urination are apparent. Pupils are pin point. Drug poisoning is suspected. Most probable cause is:
**Core Concept**
The patient's symptoms, including convulsions, hypertension, diarrhea, sweating, urination, and pinpoint pupils, suggest a diagnosis of organophosphate poisoning. Organophosphates are a class of chemical compounds used as insecticides, which can cause a cholinergic crisis when ingested or absorbed through the skin.
**Why the Correct Answer is Right**
The patient's symptoms are consistent with a cholinergic crisis, which occurs when acetylcholine binds to muscarinic and nicotinic receptors in excess. Organophosphates inhibit acetylcholinesterase, the enzyme responsible for breaking down acetylcholine. As a result, acetylcholine accumulates in the synaptic cleft and binds to its receptors, leading to overstimulation of the parasympathetic nervous system. This causes symptoms such as bradycardia, hypotension, diarrhea, sweating, urination, and pinpoint pupils, as well as seizures and muscle weakness.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not relevant to the patient's symptoms. While certain medications can cause seizures and hypertension, the combination of symptoms presented by Sunder Lal is more consistent with organophosphate poisoning.
**Option B:** This option is incorrect because the patient's symptoms do not suggest a diagnosis of opioid overdose. Opioid overdose typically presents with respiratory depression, miosis (not pinpoint pupils), and decreased bowel activity.
**Option C:** This option is incorrect because the patient's symptoms do not suggest a diagnosis of sympathomimetic toxicity. Sympathomimetic toxicity typically presents with tachycardia, hypertension, and mydriasis (not pinpoint pupils).
**Clinical Pearl / High-Yield Fact**
In cases of suspected organophosphate poisoning, atropine and pralidoxime are the mainstay of treatment. Atropine blocks the effects of excess acetylcholine at muscarinic receptors, while pralidoxime reactivates acetylcholinesterase.
**Correct Answer: D. Organophosphate poisoning.**