Why is sepsis not detected in blood work?

This is not correct. Sepsis can indeed be detected in blood work. There are various blood tests that can help in diagnosing and monitoring sepsis, including:

1. Complete Blood Count (CBC): A CBC measures the levels of different blood cells, including white blood cells (WBCs), red blood cells (RBCs), and platelets. In sepsis, the WBC count may be elevated due to the body's inflammatory response to infection. A low platelet count may also be seen.

2. C-Reactive Protein (CRP) Test: CRP is a protein produced by the liver in response to inflammation. Elevated CRP levels can indicate the presence of sepsis or other inflammatory conditions.

3. Procalcitonin (PCT) Test: PCT is a hormone produced by the thyroid gland. Increased PCT levels can be a sign of bacterial infection, and high PCT levels are often associated with sepsis.

4. Blood Culture: A blood culture involves taking a sample of blood and incubating it in a laboratory to see if bacteria or other microorganisms are present. A positive blood culture can confirm the presence of an infection and help identify the specific pathogen causing sepsis.

5. Lactate Level Test: Elevated levels of lactate in the blood can indicate tissue hypoxia and poor oxygen delivery, which can be associated with sepsis.

These tests, along with other clinical findings, such as vital signs, physical examination, and medical history, play a crucial role in the diagnosis and management of sepsis.