This is an open-label dynamic whole-body PET/CT (positron emission tomography/computed tomography) study for investigation of radiation dosimetry, plasma pharmacokinetics, biodistribution, safety and diagnostic performance of 18F-FDS in healthy volunteers and patients with suspected infection. A single dose of nearly 370 MBq 18F-FDS will be intravenously injected into healthy volunteers and patients with suspected infection. Visual and semiquantitative method will be used to assess the PET/CT images. Changes of blood pressure, pulse, respiration, temperature, routine blood and urine tests, serum alanine aminotransferase, albumin, and creatinine, and any adverse events will be collected from the volunteers. Adverse events will also be observed in the patients.

In clinical microbiology, pathogenic enterobacteriaceae are differentiated from other organisms by selectively metabolizing sorbitol. They exclusively express the enzyme sorbitol-6-phosphate dehydrogenase, which is the enzyme responsible for initiating sorbitol metabolism. 2-[18F]-fluorodeoxysorbitol (18F-FDS) is a positron-emitting analog of sorbitol. The substitution of the hydroxyl group by fluorine at the C-2 position, however, completely abrogates the recognition by mammalian sorbitol dehydrogenase.18F-FDS could be a suitable probe to selectively label and tomographically image enterobacteriaceae in vivo.

For further interests in clinical translation of 18F-FDS, an open-label dynamic whole-body PET/CT study was designed to investigate radiation dosimetry, plasma pharmacokinetics, biodistribution, safety and diagnostic performance of 18F-FDS in healthy volunteers and patients with suspected infection. A single dose of nearly 370 MBq 18F-FDS will be intravenously injected into healthy volunteers and patients with suspected infection. Visual and semiquantitative method will be used to assess the PET/CT images. Changes of blood pressure, pulse, respiration, temperature, routine blood and urine tests, serum alanine aminotransferase, albumin, and creatinine, and any adverse events will be collected from the volunteers. Adverse events will also be observed in the patients.

Inclusion Criteria:

• Healthy volunteers:

  o Males and females, ≥18 years old

• Infectious patients:

  • Males and females, ≥18 years old
  • Characteristic clinical signs, symptoms and laboratory tests suggesting the diagnosis of infectious disease.
  • The diagnosis of infection is based on The Centres for Disease Control and Prevention (CDC) criteria for diagnosing infection. They rely on a combination of clinical, radiological, operative, microbiological, and histological findings, in addition to results of other laboratory tests, such as the white blood cell count, erythrocyte sedimentation rate, and C reactive protein value.

Exclusion Criteria:

• Females planning to bear a child recently or with childbearing potential
• Renal function: serum creatinine >3.0 mg/dL (270 μM/L)
• Liver function: any hepatic enzyme level more than 5 times upper limit of normal.
• Known severe allergy or hypersensitivity to IV radiographic contrast.
• Patients not able to enter the bore of the PET/CT scanner.
• Inability to lie still for the entire imaging time because of cough, pain, etc.
• Inability to complete the needed examinations due to severe claustrophobia, radiation phobia, etc.
• Concurrent severe and/or uncontrolled and/or unstable other medical disease that, in the opinion of the Investigator, may significantly interfere with study compliance.