**Question:** All of the following cause increased ESR except

A. Anemia
B. Hypothyroidism
C. Chronic kidney disease
D. Malaria

**Core Concept:** Erythrocyte sedimentation rate (ESR) is an inflammation-based test that measures the rate at which red blood cells (erythrocytes) sediment in a blood sample over one hour. Increased ESR indicates an elevated inflammatory response in the body.

**Why the Correct Answer is Right:** Option D, Malaria, is an infectious disease caused by Plasmodium parasites. While malaria can cause fever, chills, and other symptoms, it does not typically lead to increased ESR due to its specific mode of action. Malaria primarily affects red blood cells, causing hemolysis and anemia, which can lead to decreased ESR.

**Why Each Wrong Option is Incorrect:**

A. Anemia (Option A) is a condition characterized by a decrease in the number of red blood cells or hemoglobin levels. As anemia results in reduced oxygen-carrying capacity, it can lead to increased ESR.

B. Hypothyroidism (Option B) is a disorder of the thyroid gland, causing low levels of thyroid hormones. Although hypothyroidism can lead to various symptoms and complications, it typically does not cause significant inflammation that would result in increased ESR.

C. Chronic kidney disease (Option C) is a long-term condition affecting the kidneys, leading to impaired renal function. Chronic kidney disease can cause inflammation due to the accumulation of waste products and uremic toxins, which may increase ESR. However, in comparison to anemia, hypothyroidism, and malaria, chronic kidney disease is less likely to directly cause increased ESR.

**Clinical Pearl:** An elevated ESR can be indicative of inflammation or infection. However, interpretation of ESR values should be combined with clinical context, patient history, and examination findings to make a proper diagnosis and guide management decisions.

**Correct Answer:** Option D (Malaria) is correct because it does not directly cause increased ESR, unlike anemia, hypothyroidism, and chronic kidney disease, which can lead to inflammation and increased ESR due to their respective pathophysiologies.