**Question:** A 25-year old male had pigmented macules over the palms, soles and oral mucosa. He also had anemia and pain in abdomen. The most probable diagnosis is:

A. Leishmaniasis
B. Pernicious anemia
C. Leprosy
D. Sickle cell anemia

**Core Concept:** The clinical presentation described in the question involves the involvement of skin, gastrointestinal tract, and blood picture with anemia. These findings are indicative of a systemic disease process.

**Why the Correct Answer is Right:**

D. Sickle cell anemia is a genetic disorder characterized by hemolytic anemia and hemoglobin S (HbS) polymerization leading to sickle-shaped red blood cells. The clinical features include anemia, fever, bone pain, and frequent infections. The skin findings described such as pigmented macules are a result of chronic hypoxia leading to increased melanin production. The abdominal pain is due to the sickle-shaped red blood cells blocking blood vessels, leading to infarction of the affected tissues.

**Why Each Wrong Option is Incorrect:**

A. Leishmaniasis: This is a parasitic infection caused by Leishmania species and presents with skin lesions, mucosal lesions, and lymphadenopathy, but not anemia or abdominal pain.

B. Pernicious anemia: This is a vitamin B12 deficiency-induced macrocytic anemia which typically presents with oral and gastrointestinal symptoms. The skin findings are not as prominent as in sickle cell anemia.

C. Leprosy: This is a chronic granulomatous infection caused by Mycobacterium leprae, presenting with cutaneous lesions, peripheral nerve dysfunction, and hypoesthesia. Anemia is not a common feature, while abdominal pain is not a typical presentation.

**Clinical Pearl:** Hemolytic anemia caused by sickle cell trait or sickle cell anemia presents with a combination of skin, gastrointestinal, and systemic symptoms due to the abnormal hemoglobin structure leading to vascular occlusion and organ damage. It is essential for students to differentiate between these conditions based on the clinical features mentioned in the question to avoid misdiagnosis and inappropriate treatment.