**Question:** A patient develops red eye, 2 two days after an episode of Malaria Probable cause is -

A. Allergic reaction
B. Vitamin deficiency
C. Rhinitis
D. Malaria

**Core Concept:** Malaria is a parasitic infection caused by Plasmodium species, transmitted to humans through the bite of infected Anopheles mosquitoes. Clinical symptoms can include fever, chills, headache, and general malaise. In some cases, complications such as respiratory distress, renal failure, and neurological manifestations can occur. Malaria can also lead to the redness of the eye, known as **retinal changes**.

**Why the Correct Answer is Right:** The correct answer, D. Malaria, is right because the red eye (retinal changes) is a common complication of malaria infection. The Plasmodium parasites invade red blood cells and cause hemolysis, leading to microangiopathic changes in the retina. These changes include hemorrhages, exudates, and papilledema.

**Why Each Wrong Option is Incorrect:**

A. Allergic reaction (Option A) is incorrect because malaria infection directly causes the red eye symptoms, not an allergic response.

B. Vitamin deficiency (Option B) is not a correct answer because malaria does not cause red eye symptoms due to vitamin deficiency.

C. Rhinitis (Option C) is unrelated to the red eye symptoms caused by malaria infection. Rhinitis refers to inflammation of the nasal mucosa, while malaria affects the retina.

**Clinical Pearl:** Malaria, despite being a parasitic infection, can present with ocular manifestations like red eye. A thorough examination, including fundoscopy, is essential to diagnose malaria in suspected cases, especially when fever and other symptoms are not present or not severe. Prompt diagnosis and treatment are crucial to prevent severe complications and improve patient outcomes. Additionally, recognizing the ocular manifestations can aid in raising suspicion for malaria in areas where the disease is endemic, although the infection is typically confirmed through blood smear examination.