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Infection Imaging
When the infection is well localized—that is, there are symptoms such as redness, swelling or heat—
sophisticated testing is not required. For many infections, however, the symptoms are not nearly so well
defined. These are generally referred to as "occult infections." Such infections may be seen in the post-operative
period or in patients with impaired immune systems. In order to properly treat patients with these problems, a
method for rapid diagnosis is necessary. Once the source of infection is located, appropriate treatment can be
instituted.
Inflamation foci
 blood flow
 vessels permeability
 migration of neutrophils to the site of infection
deposit of transferrin
3-phase bone scan
nanocoloide
leucocyte scan
Gallium sc.
67-Ga scintigraphy
67-Ga T1/2=78 h, g-emiter
binds with transferrin in the serum, lactofferin in the leukocytes, ferrytin of macrophages, siderophores (low
molecular weight compounds that facilitate iron uptake by microorganisms) of bacterias
uptake: bones., liver, spleen, bowel, salivary glands, thymus, breasts
Indications: chronic process, oportunistic infections, FUO, osteomyelitis
overall accuracy is over 90% for infections
- 60% for infections in the abdomen
In patients who are HIV positive, gallium imaging may provide the first sign of dangerous lung infections
Gallium is very accurate in finding bone infections
Gallium scan showing uptake throughout the
lungs in an HIV-positive patient with fever and
an unknown source of infection. The findings
indicated a diffuse pneumonia, not well seen on
the x-ray.
In vitro-labelled leukocyte scan
111-In-oxine, chinolinone (0,5 mCi)
99m-Tc-exametazime (HMPAO) (3-15 mCi)
dyfusion to leukocyte
bound with the nucleus and the mitochondrium
necessity of leukocytes isolation from the patients
aqusition after 1, 3, 24 h p.i., possibly SPECT
Indications
acute inflamatory process
FUO
abscessus of abdomen
osteomyelitis
Infection near endoprothesis
inflamation of the bowel
In vivo-labelled leukocyte scan - LeukoScan
99m-Tc-MOAB against nonspecific cross-reacting antigen (NCA-90)
sensitivity 90%
alergic reaction (HAMA) 40%
indications:
osteomyelitis, soft tissue infection, abscessus, vascular prothesis infection
Policlonal IgG
labelled with 111-In, 99m-Tc
visualisation of any infection, inflamatory process, tumors
sensitivity 92%
the best quality of images after 2-3 days
Nanocolloids
human serum albumin Ø <80 nm
passive transport through vessel wall
aquisiton after 1 h
uptake in the liver and th spleen
TUMORS
67-Ga scintigraphy
HD, NHL - residual mass after therapy,
response to therapy, recurence
Uptake in the lymph nodes:
mediastinum, neck (60-70%)
periaortal, spleen (30%)
groin, thigh (10%)
uptake corelates with activity of the disease
Lung cancer
Liver cancer (hepatoma)
99m-Tc-MIBI scintigraphy
Mitochondrial uptake
reflect P-gp expression (permeability glycoprotein)
Indications:
Parathyroid adenoma
Gliomas
Breast cancer
Thyroid cancer
Lung cancer
Lymphomas