INFECTION & INFLAMMATION IMAGING

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1 INFECTION & INFLAMMATION IMAGING Radiopharmaceutical Drug Interactions & Other Interesting Case Studies MICHELLE RUNDIO, CNMT NCT MBA PCI NUCLEAR

2 IN-111 WHITE BLOOD CELL IMAGING Interactions, Imaging Parameters & Interesting Case Studies

3 CLINICAL INDICATIONS infection and inflammation in fever of unknown origin to survey for site of infection in febrile post operative patients without signs of symptoms evaluation of infection that may exist with fluid collections and or healing wounds (CT and MRI ineffective) inflammatory bowel disease site location osteomyelitis vascular graft and shunt infections and mycotic aneurysms

4 IMAGING PROTOCOLS injection of Radiopharmaceutical with 1-2 hours of cell labeling 1-4 hour delays hour delays planar and WB images (10 mins / mins) 173 and 247keV photo peak windows (MEHR)

5 BIODISTRIBUTION spleen (critical organ) liver diffuse bone marrow major blood vessels can be seen no bowel or bladder*

6 POSITIVE TESTING 30-50% of infections are visualized by 4h post injection! more than 90% of sites are visualized by 24 hours post injection

7 POTENTIAL DRUG INTERACTIONS WITH WBC IMAGING antibiotics / corticosteroids lidocaine! penicillin and other abx decreased or absent uptake into abscess!! visualization of the colon

8 CAUSES OF FALSE NEGATIVE non-pyogenic abscess vertebral osteomyelitis chronic low grade infection parasitic infections hyperglycemia corticosteroid therapy

9 CAUSES OF FALSE POSITIVES GI Bleeding Healing Fractures Swallowed Leukocytes (lung or oropharyngeal disease) Hematomas Tumors Accessory Spleen Renal Transplant Pseudoaneurysm

10 INTERESTING CASES AND VARIANTS

11 POSITIVE TEST FOR POSTOPERATIVE ABDOMINAL WOUND INFECTION

12 UPTAKE IN A PATIENT WITH ASPLENIA

13 PATIENT WITH SPLEENOMEGALY

14 DUAL IMAGING In-111 WBC and Tc99m MDP Imaging Parameters & Interesting Case Studies

15 IMAGING PROTOCOLS AND CLINICAL USES simultaneous imaging can be effective for diagnosing osteomyelitis, patients with bone hardware or previous break, or distinguishing other areas of infection with known bone infection Dual In-111 WBC / Bone Marrow Dual imaging is also helpful to detect infected hardware/ prosthetics

16 IMAGING SPECIFICS Tc99m injection on the same day as In111 WBC Imaging (24 hour delay) acquired with 2 windows running concurrently (140keV and 247 kev windows), or images acquired immediately following each other with the same patient positioning Images usually acquired to 50K counts simultaneously

17 POTENTIAL DRUG INTERACTIONS FOR MDP iron compounds decreased bone uptake gentamicin, vinchristine, increased renal uptake amphotericin corticosteroids absent bone activity; especially at major joints estrogens uptake of RP in the breast aluminum containing antacids uptake in the liver

18 CASE STUDY #1 61 y/f - right 4th and 5th metatarsal fractures 12 yrs ago s/p open reduction and internal fixation 2 to 3 years ago. Postoperatively developed staphylococcus infection of right foot - Rx antibiotics. In 4/2008 there was 5th metatarsal hardware loosening s/p removal. There is concern for recurrence of infection.

19 INTERESTING CASES - DUAL IMAGING

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28 CASE STUDY #2 62-YEAR-OLD FEMALE STATUS POST EXPLANTATION OF A TOTAL HIP ARTHROPLASTY 2 MONTHS AGO, COMPLETED ANTIBIOTICS 6 WEEKS PRIOR TO THIS EXAM**; RECENT HIP ASPIRATION PERFORMED!

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33 HIP TAP RESULTS Polymorphonuclear leukocytes No organisms on gram stain No growth PROPOSED POST-HIP ASPIRATION INFLAMMATION

34 CASE STUDY #3 67 year old woman with left ankle osteoarthritis status post left ankle arthroplasty in March There is clinical concern for infection.! Dual Isotope Imaging + SPECT CT Indium WBC Study

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40 CASE STUDY #4 65 year old male status post liver transplant in 2007, Ascending aortic aneurysm repair and aortic valve replacement on 03/23/2010. Now presents with chills.

41 INITIAL FINDINGS & RECOMMENDATIONS! CT Scan shows no obvious sources for infection Referred to nuclear medicine to rule out infection Which study would you recommend?

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43 LEUKOCYTE SCINTIGRAPHY WITH TOMOGRAPHY (SPECT-CT) 8/5/2010

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46 LEUKOCYTE SCINTIGRAPHY WITH TOMOGRAPHY (SPECT-CT) 8/5/ Pattern most compatible with a focus of infection in the ascending portion of the aortic graft, with extension of activity into the soft tissue just deep to the sternotomy site.! 2. Another focus of increased activity along the prosthetic aortic valve may represent a second area of infectious involvement.

47 DISCHARGE NOTES The patient has recurrent bacteremia and most likely has a graft infection as well. He should be treated as prosthetic valve endocarditis with vancomycin, rifampin and gentamicin. The patient was discharged on 08/10/2010 on antibiotics.

48 CASE STUDY #4 PATIENT WITH FEVER OF UNKNOWN ORIGIN, REST OF HISTORY WITH HELD IN-111 WBC SCAN TO R/O INFECTION!

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51 CT SCAN

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54 DIAGNOSES! Colitis Osteomyelitis of L2-L3 confirmed with spinal biopsy (enterococcus)

55 GALLIUM VS. INDIUM WBC IMAGING

56 WHEN IS EACH APPROPRIATE? Indium is preferred for abdominal infection because of lack of normal bowel activity. Indium has a low sensitivity for spine infection, osteomyelitis and discitis. More than 60% of spine infections may appear photopenic, which is a nonspecific finding.! Ga-67 is taken up in cortical bone as well as marrow, so there is increased uptake with bone remodeling. Gallium can be useful for discitis because there is often a soft tissue component.

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58 GALLIUM IMAGING Not preferred for abdominal sources of infection due to biodistribution more extensive gut uptake taken up in areas of inflammation and infection can show inflammation that happens with extensive infection

59 POTENTIAL DRUG INTERACTIONS FOR GALLIUM IMAGING amiodarone, addictive drugs of abuse, chemotherapy agents iron / vinchristine certain antibiotics diffuse pulmonary uptake increased renal elimination & decreased abscess uptake localization of RP in the bowel, thymus, and potential increased soft tissue uptake

60 CASE STUDY # 5 57 year old with back pain patient had L4 / L5 Lumbar Fusion in 2008 CT scan suggested possible source of infection if clinically the infection was warranted gallium study ordered to look for source of infection in lower back

61 L4-4/18/2008 L5-4/18/2008 L4-08/05/2008 L5-08/05/2008

62 L4 L5

63 g 2008

64 L4 L5

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67 THE FUTURE OF WHITE BLOOD CELL IMAGING In-WBC Imaging has become even more effective when paired with other diagnostics: Dual Imaging (MDP / SC) SPECT CT Supplemental Gallium Imaging PET scans

68 THANK YOU!! Images Courtesy of Dr. Akash Sharma & Dr. Barry Seigel Mallinckrodt Institute of Radiology - Barnes Jewish Hospital St. Louis MO