infection mini lecture 2013

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THE ROLE OF NUCLEAR

MEDICINE IN

INFECTION/INFLAMMATIO

N

A.Hussein S. Kartamihardja

Department of Nuclear Medicine and

Molecular Imaging

Faculty of Medicine Universitas Padjadjaran

Dr. Hasan Sadikin General Hospital

Infection

• a major cause of mortality and morbidity not only in the developing countries, but globally.

• Multi drug resistant and tuberculosis are increasing and provide diagnostic, therapeutic and infection control challenges.

• In most of case the diagnosis of infection is very clear based on history, physical examination and identification of microorganisms in pus, blood, or body secretion.

• But in many cases imaging modalities are needed to detect and locate the site of infection.

Department of Nuclear Medicine and Molecular Imaging

Padjadjaran University – Dr. Hasan Sadikin Hospital

IMAGING TECHNIQUES FOR DIAGNOSIS AND

LOCALIZATION OF INFECTION AND INFLAMMATION

• Based on anatomical changes

1.

Conventional x-ray

2.

CT scan

3.

MRI

4.

USG

• Based on physiological changes

• Nuclear medicine

Nuclear medicine techniques are often used in the context of fever of unknown origin or suspected bacterial infection to aid diagnosis and to establish the need for antimicrobial treatment.

NUCLEAR MEDICINE IN INFECTION AND

INFLAMMATION

• Detection of infection / inflammation is a challenging problem in clinical practice, because it may have important implications for the management of patients with infectious or inflammatory diseases.

• NM played an important role in the diagnosis and localization of infection and inflammation since the use of Gallium-67 citrate in 1970 ’ s

Department of Nuclear Medicine and Molecular Imaging

Padjadjaran University – Dr. Hasan Sadikin Hospital

RADIOPHARMACEUTICAL FOR INFECTION AND

INFLAMMATION

The radiopharmaceutical used for imaging infection and inflammation accumulates in the infectious/inflammatory lesion due to the locally changed physiological condition.

Characterized by :

enhanced blood flow

enhanced vascular permeability

influx of white blood cells

Non specific

Ga-67 citrate

Tc-99m albumin

Specific process

In-111 oxine-wbc

Tc-99m HMPAO-wbc

Tc-99m Nano colloid Peptide labeled

F-18 FDG

Specific disease

Tc-99m cyprofloxacine

Monoclonal antibody

Tc-99m UBI

Polyclonal-antibody (Tc-99m-HIg) Tc-99m Ethambutol

The ideal radiopharmaceutical for infection/inflammat ion imaging

1. efficient accumulation and good retention in inflammatory foci

2. rapid clearance from background

3. no accumulation in non-inflamed tissues

4. no side-effects

5. low cost (Tc-99m) and easy preparation (kit formulation)

6. discrimination between infection and non-microbial inflammation

Department of Nuclear Medicine and Molecular Imaging

Padjadjaran University – Dr. Hasan Sadikin Hospital

• Ability to image osteoblastic activity.

• Widely available, accurate and costeffective examination

• The increased Tc-99m MDP uptake is a good indicator of infection or loosening with 100% sensitivity and

72% specificity.

(Weiss et al 1979)

• Recommended as an initial study.

Negative results could be treated conservatively.

• To improve the accuracy in hip prosthesis, the baseline scan should be done 9-12 months after surgery and at a time when the patients develop symptoms

• Three-phase bone imaging.

• Combines dynamic and static bone imaging

• Arterial, soft-tissue and bonemetabolic phase

BONE IMAGING

WHITE BLOOD CELL LABELING

• Leukocytes are the major component on inflammatory and immune responses

• Normally about 90% of neutrophil pool is in the bone marrow, only 2-

3% is in the circulation

• In an acute inflammatory, neutrophils migrate toward an attractant

(chemotaxis), increase their adhesiveness, aggregate, adhere to endothelial surface, phagocytize the infectious agents or foreign bodies and enzymatically destroy it within cytoplasmic body.

• Neutrophils survive in tissue only 2-3 days

• In-111 oxine or Tc-99m HMPAO

• In-111 is cyclotron produced radionuclide

• Half life 67 hrs

• Gamma photon 173 keV and 247 keV

• In-111 oxine label blood cell indiscriminately

• Labeling wbc with I-111 oxine will take about 2 hours

• Careful handling is necessary to avoid damaging the cell and other contaminations

• Labeling efficiencies of more than

75% is sufficient

• Increased lung uptake can be used as a parameter of poor labeling quality due to cell damage

In-111-labeled white blood cell

89-year-old male with FUO

Tc-99 m HMPAO WBC

• Hexamethylpropyleneamineoxine, is a lipophilic and readily crosses the white cell membrane

• Intracellularly, it changes into a hydrophilic complex and becomes trapped, bound to mitochondria and the nucleus

• Widely use for diagnosing and localizing infection and inflammation

• Preparation and procedure of imaging is similar to In-111 oxine, except photopeak at 140 keV.

Both the 90 min peptide and

24 h in vitro -labeled leukocyte images demonstrate focal, intense uptake in the distal third of the left tibia of a 45-year-old man with osteomyelitis of this bone.

Tc-99m ciprofloxacin

• There are many radiopharmaceutical have been used for diagnosing and localizing of infection and inflammation, but to differentiate bacterial infection from sterile inflammation is still a problem until 1995 when Infecton was discovered.

• Infecton, basically is cyprofloxacine, a broad spectrum antibiotic

• Invitro studies showed, that infecton can be trapped by living pathogen bacteria and destroy DNA gyrase, but not nonpathogen bacteria

• Infecton still can be trapped in bacterias resistant to cyprofloxacine

Tc-99m HMPAO-WBC

Department of Nuclear Medicine

Padjadjaran University – Dr. Hasan Sadikin Hospital

Tc-99m Infecton

THE USE OF 99MTC-CIPROFLOXACIN (INFECTON) SCINTIGRAPHY

IN DETECTION OF CERVICAL LYMPHADENITIS.

AISYAH ELLIYANTI*, KURNIADI**, A.HUSSEIN S KARTAMIHARDJA*, AND J OHAN S MASJHUR*

*DEPARTMENT OF NUCLEAR MEDICINE **DEPARTMENT OF SURGERY DR. HASAN SADIKIN

HOSPITAL BANDUNG-INDONESIA

23 subjects with cervical lymphadenopathy; histopathologic examination by open biopsy

Results :

• Positive scan : 16

1 / 16: tumor metastases.

• Negative scan : 7

2 / 7: tuberculous infection treated by tuberculoustatic for one year and amoxicillin

Sensitivity

Specificity

93%

71%

Positive predictive value 88%

Negative predictive value 83%

Tc-99m Ciprofloxacin

Spondylitis Tuberculosis

• Specific antituberculous

• Micoic acid in baterial wall

• Tc-99m labelled

Three serious foot complications of diabetes mellitus

 Foot ulcerations,

 infections, and

 Charcot neuropathic osteoarthropathy

• It is needed to determine

• which of treatments are most effective.

• How to effectively prevent those ulcerations which are leading to amputation

• The detection of diabetic foot infection can be difficult.

With clinical examination, it is difficult to differentiate between soft-tissue infection and osteomyelitis.

• The erythrocyte sedimentation rate is not specific.

• Bone biopsy is not always performed because it is an invasive procedure that loses its reliability when the biopsy fragment is contaminated by cutaneous bacteria.

• Imaging modalities are valuable for the diagnosis and crucial in the evaluation of infections in DM.

the journal of nuclear medicine • vol. 52 • no. 7 • july 2011

Hell J Nucl Med 2010; 13(2):150-157

• SPECT/CT can represent a potential tool for diagnosing diabetic foot infection by 99m Tc-HMPAO–labeled leukocytes by differentiating between bone and soft-tissue involvement and by more precisely defining the extent of the disease, thus supporting treatment planning and avoiding more invasive procedures

• TPBS is a useful clinical tool to assist the orthopedist in making a more objective decision regarding the amputation level of ischemic lower limbs and surgical procedure to be employed, prior to surgery

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