NMP 2 - SPECT AND SPECT/CT

Gallium-67 Citrate (Ga-67)

● Binds to lactoferrin released from dying leukocytes.

● Binds to bacterial siderophores.

● Localizes at infection sites due to increased vascular permeability and inflammatory response.

● Offers the best image resolution due to optimized energy for gamma camera, reduced background activity, and short half-life that allows for the administration of higher dose

Indium-111 Oxine–Labeled Leukocytes (In-111 WBCs)

● Uses diapedesis & chemotaxis to migrate toward inflammatory sites.

● Directly labels circulating leukocytes, which then move to areas of infection.

● High specificity for inflammation and infection.

Technetium-99m Hexamethylpropyleneamine Oxime (Tc-99m HMPAO)– Labeled Leukocytes

● Similar to In-111 WBCs but clears faster from the blood.

● Uptake at sites of infection is due to migration of labeled leukocytes.

Fluorine-18 Fluorodeoxyglucose (F-18 FDG)

● Increased uptake in activated granulocytes and macrophages at infection sites.

● Cellular glucose metabolism is upregulated in inflammatory processes

Antigranulocyte Monoclonal Antibodies (Tc-99m Sulesomab, In-111 Fanolesomab)

● Antibody-antigen binding to activated leukocytes at inflammation sites
● Somab are antibodies used for localization of active inflammation

Chemotactic Peptides and Cytokines (Tc-99m IL-8)

● Bind to specific cell-surface receptors on neutrophils.
● Stimulate chemotaxis, leading to rapid localization at infection sites

Tc-99m Ciprofloxacin

● Antibody-antigen binding to activated leukocytes at inflammation sites
● Ciprofloxacin is an antibiotic very specific for damaging bacterial DNA