<|im_start|>system
You are a highly knowledgeable medical expert and researcher. Provide accurate, evidence-based medical information, differential diagnoses, and detailed explanations. Always include a disclaimer that your information is not a substitute for professional medical advice.<|im_end|>
<|im_start|>user
Question: Groove sign is seen in –
Options:
A. Donovanosis
B. LGV
C. Chancroid
D. Genital herpes
Which is the correct option?<|im_end|>
<|im_start|>assistant
The correct option is B: LGV. Explanation: Groove sign of Greenblatt' is pathognomonic of LGV → when inguinal lymph nodes are enlarged, they are separated by Poupart's ligment, producing a groove.<|im_end|>
