A 30 years old male patient presents with complaints of weakness in right upper and both lower limbs of last 4 months. He developed digital infarcts involving 2nd and 3rd fingers on right side and 5th finger on left side. On examination, BP was 160/140 mm Hg, all peripheral pulses were palpable and there was asymmetrical neuropathy. Investigations showed a Hb 12 gm, TLC — 12000 Cu mm, Platelets 430,000; ESR — 49 mm. Urine examination showed proteinuria and RBC — 10-15/hpf with no casts. Which of the following is the most likely diagnosis?

**Core Concept**
The patient presents with symptoms of polyneuropathy, digital infarcts, and systemic hypertension, which suggests a systemic vasculitic process. The presence of hypertension, proteinuria, and hematuria points towards a renal involvement.

**Why the Correct Answer is Right**
The clinical presentation of digital infarcts, polyneuropathy, and systemic hypertension in a young patient is highly suggestive of **Eggshell Calcification** associated with **Buerger's disease** or **Thromboangiitis obliterans**. However, the presence of renal involvement and hypertension in this case makes **Buerger's disease** less likely. The correct answer is related to a systemic vasculitis. The patient's symptoms are consistent with **Polyarteritis nodosa (PAN)**, which is a medium-vessel vasculitis that can cause renal involvement, hypertension, and digital infarcts.

**Why Each Wrong Option is Incorrect**
**Option A:** Buerger's disease typically presents with symptoms of claudication and ischemia in the lower limbs, but it does not typically cause renal involvement or digital infarcts.
**Option B:** Thromboangiitis obliterans is a form of Buerger's disease that affects small and medium-sized arteries and veins. While it can cause digital infarcts, it is less likely to cause renal involvement or hypertension.
**Option C:** Giant cell arteritis typically affects older adults and presents with symptoms of headache, jaw claudication, and visual disturbances. It does not typically cause renal involvement or digital infarcts.
**Option D:** Kawasaki disease is a medium-vessel vasculitis that affects children and presents with symptoms of fever, rash, and lymphadenopathy. It does not typically cause renal involvement or digital infarcts.

**Clinical Pearl / High-Yield Fact**
The presence of hypertension, proteinuria, and hematuria in a young patient with digital infarcts and polyneuropathy should raise the suspicion of a systemic vasculitic process, such as Polyarteritis nodosa (PAN).

**Correct Answer:** C. Polyarteritis nodosa (PAN)

✓ Correct Answer: C. Polyaeritis nodosa