A 48 year old male presents with non-itchy generalised papulo-nodular lesion of three months duration. Physical examination does not show any other abnormaly.Slit smear from a nodule does not show AFB. Blood VDRL is reactive 1:2 dilution.The most likely diagnosis is-

**Core Concept**
The patient's presentation of non-itchy generalized papulo-nodular lesions, negative AFB (Acid-Fast Bacilli) on slit smear, and reactive VDRL (Venereal Disease Research Laboratory) test suggests a diagnosis related to a systemic disease with skin manifestations.

**Why the Correct Answer is Right**
The patient's reactive VDRL test indicates the presence of a treponemal infection, which is consistent with **Syphilis**. The absence of AFB on slit smear rules out Leprosy, a common cause of papulo-nodular lesions. The non-itchy nature of the lesions and the generalised distribution also make other dermatological conditions less likely. The reactive VDRL test is a specific indicator of a treponemal infection, which is a hallmark of Syphilis.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it would require more specific diagnostic evidence, such as a positive AFB test or a different pattern of skin lesions.
* **Option B:** This option is incorrect because it doesn't account for the reactive VDRL test, which is a key indicator of a treponemal infection.
* **Option C:** This option is incorrect because it would require a different pattern of skin lesions and possibly other systemic symptoms.

**Clinical Pearl / High-Yield Fact**
Reactive VDRL test is a key diagnostic indicator of Syphilis, and the absence of AFB on slit smear helps to rule out Leprosy.

**Correct Answer: C. Secondary Syphilis**

✓ Correct Answer: D. Secondary syphilis