Imaging for infection: from visualization of inflammation to visualization of microbes

Leptospirosis-Induced Septic Shock and Multi-Organ Dysfunction Syndrome: A Complex Case of Zoonotic Infection in a Young Female Patient

Leptospirosis, a zoonotic infection caused by the Leptospira bacteria, can manifest with varying clinical severities, ranging from subclinical disease to severe multiorgan failure. This progression to severe multiorgan failure, also known as multi-organ dysfunction syndrome (MODS), is a life-threatening condition characterized by the dysfunction of two or more organ systems. Often, MODS is a consequence of events triggered by underlying pathologies, such as severe infections, including those caused by Leptospira. Here, we present a case report of a 29-year-old female patient who initially sought care for increased temperature, fatigue, diarrhea, and vomiting. The patient exhibited signs of septic shock (SS). Her medical history raised suspicion of multiple potential sources of infection. She experienced cat scratch several days before admission, accompanied by an enlarged inguinal lymph node and a history of frequent interaction with animals, as well as freshwater exposure, which prompted investigations into various zoonotic infections. Empiric treatment was started, and, subsequently, after several days, Leptospira titer came back positive. Over the hospitalization course, the patient developed multi-organ failure, which was attributed to the underlying Leptospira infection. The complexity and severity of the patient's condition underscore the far-reaching impact of leptospirosis in precipitating a spectrum of systemic complications culminating in multiorgan failure. The treatment interventions yielded successful outcome, and the patient recovered in one month. This case report highlights the difficulties in diagnosing and treating patients with multiple possible sources of infection. it emphasizes the need for a careful history-taking and high level of suspicion for zoonotic infections in patients with a history of animal exposure and clinical symptoms suggestive of infectious diseases.

Preclinical Research Highlighting Contemporary Targeting Mechanisms of Radiolabelled Compounds for PET Based Infection Imaging

It is important to constantly monitor developments in the preclinical imaging arena of infection. Firstly, novel radiopharmaceuticals with the correct characteristics must be identified to funnel into the clinic. Secondly, it must be evaluated if enough innovative research is being done and adequate resources are geared towards the development of radiopharmaceuticals that could feed into the Nuclear Medicine Clinic in the near future. It is proposed that the ideal infection imaging agent will involve PET combined with CT but more ideally MRI. The radiopharmaceuticals currently presented in preclinical literature have a wide selection of vectors and targets. Ionic formulations of PET-radionuclides such 64CuCl2 and 68GaCl2 are evaluated for bacterial infection imaging. Many small molecule based radiopharmaceuticals are being investigated with the most prominent targets being cell wall synthesis, maltodextrin transport (such as [18F]F-maltotriose), siderophores (bacterial and fungal infections), the folate synthesis pathway (such as [18F]F-PABA) and protein synthesis (radiolabelled puromycin). Mycobacterial specific antibiotics, antifungals and antiviral agents are also under investigation as infection imaging agents. Peptide based radiopharmaceuticals are developed for bacterial, fungal and viral infections. The radiopharmaceutical development could even react quickly enough on a pandemic to develop a SARS-CoV-2 imaging agent in a timely fashion ([64Cu]Cu-NOTA-EK1). New immuno-PET agents for the imaging of viruses have recently been published, specifically for HIV persistence but also for SARS-CoV2. A very promising antifungal immuno-PET agent (hJ5F) is also considered. Future technologies could include the application of aptamers and bacteriophages and even going as far as the design of theranostic infection. Another possibility would be the application of nanobodies for immuno-PET applications. Standardization and optimization of the preclinical evaluation of radiopharmaceuticals could enhance clinical translation and reduce time spent in pursuing less than optimal candidates.

Infection as an under-recognized precipitant of acute heart failure: prognostic and therapeutic implications

As the prevalence of heart failure (HF) continues to rise, prompt diagnosis and management of various medical conditions, which may lead to HF exacerbation and result in poor patient outcomes, are of paramount importance. Infection has been identified as a common, though under-recognized, precipitating factor of acute heart failure (AHF), which can cause rapid development or deterioration of HF signs and symptoms. Available evidence indicates that infection-related hospitalizations of patients with AHF are associated with higher mortality, protracted length of stay, and increased readmission rates. Understanding the intricate interaction of both clinical entities may provide further therapeutic strategies to prevent the occurrence of cardiac complications and improve prognosis of patients with AHF triggered by infection. The purpose of this review is to investigate the incidence of infection as a causative factor in AHF, explore its prognostic implications, elucidate the underlying pathophysiological mechanisms, and highlight the basic principles of the initial diagnostic and therapeutic interventions in the emergency department.

99mTc-Labeled, Colistin Encapsulated, Theranostic Liposomes for Pseudomonas aeruginosa Infection

Infectious diseases are still the major issue not only due to antibiotic resistance but also causing deaths if not diagnosed at early-stages. Different approaches including nanosized drug delivery systems and theranostics are researched to overcome antibiotic resistance, decrease the side effects of antibiotics, improve the treatment response, and early diagnose. Therefore, in the present study, nanosized, radiolabeled with ^99mTc, colistin encapsulated, neutral and cationic liposome formulations were prepared as the theranostic agent for Pseudomonas aeruginosa infections. Liposomes exhibited appropriate physicochemical properties thanks to their nano-particle size (between 173 and 217 nm), neutral zeta potential value (about - 6.5 and 2.8 mV), as well as encapsulation efficiency of about 75%. All liposome formulations were radiolabeled with over 90% efficiency, and the concentration of stannous chloride was found as 1 mg.mL^-1 to obtain maximum radiolabeling efficiency. In alamar blue analysis, neutral liposome formulations were found more biocompatible compared with the cationic formulations. Neutral colistin encapsulated liposomes were found to be more effective against P. aeruginosa strain according to their time-dependent antibacterial effect, in addition to their highest bacterial binding capacity. As conclusion, theranostic, nanosized, colistin encapsulated, neutral liposome formulations were found as promising agents for the imaging and treating of P. aeruginosa infections.

Acute liver injury in COVID-19 patients hospitalized in the intensive care unit: Narrative review

In recent years, humanity has been confronted with a global pandemic due to coronavirus disease 2019 (COVID-19), which has caused an unprecedented health and economic crisis worldwide. Apart from the respiratory symptoms, which are considered the principal manifestations of COVID-19, it has been recognized that COVID-19 constitutes a systemic inflammatory process affecting multiple organ systems. Across the spectrum of organ involvement in COVID-19, acute liver injury (ALI) has been gradually gaining increasing attention by the international scientific community. COVID-19 associated liver impairment can affect a considerable proportion of COVID-19 patients and seems to correlate with the severity of the disease course. Indeed, COVID-19 patients hospitalized in the intensive care unit (ICU) run a greater risk of developing ALI due to the severity of their clinical condition and in the context of multi-organ failure. The putative pathophysiological mechanisms of COVID-19 induced ALI in ICU patients remain poorly understood and appear to be multifactorial in nature. Several theories have been proposed to explain the occurrence of ALI in the ICU setting, such as hypoperfusion and ischemia due to hemodynamic instability, passive liver congestion as a result of congestive heart failure, ischemia-reperfusion injury, hypoxia due to respiratory failure, mechanical ventilation itself, sepsis and septic shock, cytokine storm, endotheliitis with concomitant coagulopathy, drug-induced liver injury, parenteral nutrition and direct cytopathic viral effect. It should be noted that no specific therapy for COVID-19 induced ALI exists. Therefore, the therapeutic approach lies in preventive measures and is exclusively supportive once ALI ensues. The aim of the current review is to scrutinize the existing evidence on COVID-19 associated ALI in ICU patients, explore its clinical implications, shed light on the underlying pathophysiological mechanisms and propose potential therapeutic approaches. Ongoing research on the particular scientific field will further elucidate the pathophysiology behind ALI and address unresolved issues, in the hope of mitigating the tremendous health consequences imposed by COVID-19 on ICU patients.

Imaging and Clinical Parameters for Distinction between Infected and Non-Infected Fluid Collections in CT: Prospective Study Using Extended Microbiological Approach

The aim of this investigation was to evaluate predictive CT imaging features and clinical parameters to distinguish infected from sterile fluid collections. Detection of infectious agents by advanced microbiological analysis was used as the reference standard. From April 2018 to October 2019, all patients undergoing CT-guided drainages were prospectively enrolled, if drainage material volume was at least 5 mL. Univariate analysis revealed attenuation (p = 0.001), entrapped gas (p < 0.001), fat stranding (p < 0.001), wall thickness (p < 0.001) and enhancement (p < 0.001) as imaging biomarkers and procalcitonin (p = 0.003) as clinical predictive parameters for infected fluid collections. On multivariate analysis, attenuation > 10 HU (p = 0.038), presence of entrapped gas (p = 0.027) and wall enhancement (p = 0.028) were independent parameters for distinguishing between infected and non-infected fluids. Gas entrapment had high specificity (93%) but low sensitivity (48%), while wall enhancement had high sensitivity (91%) but low specificity (50%). CT attenuation > 10 HU showed intermediate sensitivity (74%) and specificity (70%). Evaluation of the published proposed scoring systems did not improve diagnostic accuracy over independent predictors in our study. In conclusion, this prospective study confirmed that CT attenuation > 10 HU, entrapped gas and wall enhancement are the key imaging features to distinguish infected from sterile fluid collections on CT.

Diagnostic challenges in postoperative intra-abdominal sepsis in critically ill patients: When to reoperate?

The present paper was done to review common diagnostic techniques used to help surgeons find the most suitable way to diagnose postoperative intra-abdominal sepsis (IAS). The topic was searched on MEDLINE, Embase, and Cochrane Library databases. Collected articles were classified and checked for their quality. Findings of selected research were included in this study and analyzed to find the best diagnostic method for intra-abdominal sepsis. IAS presents severe morbidity and mortality, and its early diagnosis can improve the outcome. Currently, there is no consensus among surgeons on a single diagnostic modality that should be used while deciding reoperation in patients with postoperative IAS. Though it has a high sensitivity for abdominal infections, computed tomography has limited applications due to mobility and time constraints. Diagnostic laparoscopy is a safe process that produces usable images, and can be used at the bedside. Diagnostic peritoneal lavage (DPL) has high sensitivity, and the patients testing positive through DPL can be subjected to exploratory laparotomy, depending on severity. Abdominal Reoperation Predictive Index (ARPI) is the only index reported as an aid for this purpose. Serial intra-abdominal pressure measurement has also emerged as a potential diagnostic tool. A proper selection of diagnostic modality is expected to improve the outcome in IAS, which presents high mortality risk and a limited time frame.

Microbial-based cancer therapy-bugs as drugs: History & the essential role of medical imaging

Microbial-based cancer therapy aims to use tumor-specific infectious microbes to fulfill the unmet medical needs for patients with difficult-to-treat malignancies. The NIH is calling to revisit the old concept from new perspectives, by incorporating advances in science and technology, to establish an alternative to the traditional categories of cancer managements. Medical imaging offers unique insight into the mechanisms of action, assessment of success/failure, and advantages/pitfalls of microbial-based cancer therapy, which in turn should facilitate the advances of this new initiative in modern medical oncology.

Molecular Imaging of Inflammatory Disease

Inflammatory diseases include a wide variety of highly prevalent conditions with high mortality rates in severe cases ranging from cardiovascular disease, to rheumatoid arthritis, to chronic obstructive pulmonary disease, to graft vs. host disease, to a number of gastrointestinal disorders. Many diseases that are not considered inflammatory per se are associated with varying levels of inflammation. Imaging of the immune system and inflammatory response is of interest as it can give insight into disease progression and severity. Clinical imaging technologies such as computed tomography (CT) and magnetic resonance imaging (MRI) are traditionally limited to the visualization of anatomical information; then, the presence or absence of an inflammatory state must be inferred from the structural abnormalities. Improvement in available contrast agents has made it possible to obtain functional information as well as anatomical. In vivo imaging of inflammation ultimately facilitates an improved accuracy of diagnostics and monitoring of patients to allow for better patient care. Highly specific molecular imaging of inflammatory biomarkers allows for earlier diagnosis to prevent irreversible damage. Advancements in imaging instruments, targeted tracers, and contrast agents represent a rapidly growing area of preclinical research with the hopes of quick translation to the clinic.

Challenges of Modeling Outcomes for Surgical Infections: A Word of Caution

Background: We developed a novel analytic tool for colorectal deep organ/space surgical site infections (C-OSI) prediction utilizing both institutional and extra-institutional American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP) data. Methods: Elective colorectal resections (2006-2014) were included. The primary end point was C-OSI rate. A Bayesian-Probit regression model with multiple imputation (BPMI) via Dirichlet process handled missing data. The baseline model for comparison was a multivariable logistic regression model (generalized linear model; GLM) with indicator parameters for missing data and stepwise variable selection. Out-of-sample performance was evaluated with receiver operating characteristic (ROC) analysis of 10-fold cross-validated samples. Results: Among 2,376 resections, C-OSI rate was 4.6% (n = 108). The BPMI model identified (n = 57; 56% sensitivity) of these patients, when set at a threshold leading to 80% specificity (approximately a 20% false alarm rate). The BPMI model produced an area under the curve (AUC) = 0.78 via 10-fold cross- validation demonstrating high predictive accuracy. In contrast, the traditional GLM approach produced an AUC = 0.71 and a corresponding sensitivity of 0.47 at 80% specificity, both of which were statstically significant differences. In addition, when the model was built utilizing extra-institutional data via inclusion of all (non-Mayo Clinic) patients in ACS-NSQIP, C-OSI prediction was less accurate with AUC = 0.74 and sensitivity of 0.47 (i.e., a 19% relative performance decrease) when applied to patients at our institution. Conclusions: Although the statistical methodology associated with the BPMI model provides advantages over conventional handling of missing data, the tool should be built with data specific to the individual institution to optimize performance.

99mTc-Leukocyte Scintigraphy Revealed Viral Pulmonary Infection in a COVID-19 Patient

Tc-leukocyte scintigraphy was performed on a 40-year-old woman with spiking fevers. A focus of intense uptake in the right upper thorax was identified, concerning for infection along the central line in the superior vena cava. Additionally, heterogeneously increased uptake in both lungs was noted, which suggested pulmonary infection. CT images of the chest showed patchy ground-glass changes in both lungs and a large consolidation in the right lower lobe, which were consistent with changes for COVID-19 (coronavirus disease 2019). Severe acute respiratory syndrome coronavirus 2 RNA test was positive. This case demonstrates that leukocyte uptake in bilateral lungs could reveal viral pulmonary infection in COVID-19.

Preparation of technetium-99m labeled ibuprofen by direct route and technetium-99m tricarbonyl route: a comparison of in vivo behaviors

In the current study, ibuprofen (ibu) which is a non-steroidal anti-inflammatory drug (NSAID) was radiolabeled with ^99mTc using two different methods: stannous chloride method (direct route) and technetium-99m tricarbonyl [^99mTc(CO)₃]⁺ route. Thus, it's aimed to investigate the radiolabeling potential of ibu for inflammation detection and to monitor if there is any difference in in vivo distribution depending on the radiolabeling route. Quality control studies of both radiolabeled ibu were performed by radiochromatographic methods (Thin Layer Liquid Radio Chromatography and High Performance Liquid Radio Chromatography). Radiolabeling yields of ^99mTc-ibu and ^99mTc(CO)₃-ibu were determined as 99.05 ± 0.83% and 91.79 ± 3.30% (n = 5), respectively. Experimental lipophilicities of both radiolabeled ibu were determined. The biological behavior of both radiolabeled ibu was investigated in healthy Albino Wistar male rats by in vivo biodistribution studies. It was seen that both radiolabeled ibuprofen showed renal excretion while organ uptakes of ^99mTc-ibu and ^99mTc(CO)₃-ibu differ against time.

Imaging Inflammation and Infection in the Gastrointestinal Tract

A variety of seemingly non-specific symptoms manifest within the gastrointestinal (GI) tract, particularly in the colon, in response to inflammation, infection, or a combination thereof. Differentiation between symptom sources can often be achieved using various radiologic studies. Although it is not possible to provide a comprehensive survey of imaging gastrointestinal GI tract infections in a single article, the purpose of this review is to survey several topics on imaging of GI tract inflammation and infections. The review discusses such modalities as computed tomography, positron emission tomography, ultrasound, endoscopy, and magnetic resonance imaging while looking at up-an-coming technologies that could improve diagnoses and patient comfort. The discussion is accomplished through examining a combination of organ-based and organism-based approaches, with accompanying selected case examples. Specific focus is placed on the bacterial infections caused by Shigella spp., Escherichia coli, Clostridium difficile, Salmonella, and inflammatory conditions of diverticulitis and irritable bowel disease. These infectious and inflammatory diseases and their detection via molecular imaging will be compared including the appropriate differential diagnostic considerations.

Towards clinical application of non-invasive imaging to detect bacterial infections

In vivo imaging technologies offer a great potential for the diagnosis of difficult-to-treat bacterial infections. A major limitation of conventional imaging modalities is the lack of specificity to distinguish the site of bacterial infection from sterile inflammation. Targeted approaches like antibiotics linked to imaging tracers for detection of various bacterial pathogens or species-specific antibodies combined with anatomical imaging modalities are currently being evaluated to overcome this problem. Considering the recent progress in optical and targeted imaging that may accelerate preclinical development programs, clinical implementation of in vivo imaging modalities to detect bacterial infection foci becomes realistic in the future.

Synthesis and evaluation of a [18F]formyl-Met-Leu-Phe derivative: A positron emission tomography imaging probe for bacterial infections

The tripeptide formyl-Met-Leu-Phe (fMLF) is a prototype of N-formylated chemotactic peptides for neutrophils owing to its ability to bind and activate the G protein-coupled formyl peptide receptor (FPR). Here, we developed an ¹⁸F-labeled fMLF derivative targeting FPR as a positron emission tomography (PET) imaging probe for bacterial infections. The study demonstrates that the fMLF derivative fMLFXYk(FB)k (X = Nle) has a high affinity for FPR (Ki = 0.62 ± 0.13 nM). The radiochemical yield and purity of [¹⁸F]fMLFXYk(FB)k were 16% and >96%, respectively. The in vivo biodistribution study showed that [¹⁸F]fMLFXYk(FB)k uptake was higher in the bacterial infected region than in the non-infected region. We observed considerably higher infection-to-muscle ratio of 4.6 at 60 min after [¹⁸F]fMLFXYk(FB)k injection. Furthermore, small-animal PET imaging studies suggested that [¹⁸F]fMLFXYk(FB)k uptake in the bacterial infected region was clearly visualized 60 min after injection.

Preclinical evaluation of potential infection-imaging probe [68 Ga]Ga-DOTA-K-A9 in sterile and infectious inflammation

The development of bacteria-specific infection radiotracers is of considerable interest to improve diagnostic accuracy and enabling therapy monitoring. The aim of this study was to determine if the previously reported radiolabelled 1,4,7,10-tetraazacyclododecane-N,N',N″,N‴-tetraacetic acid (DOTA) conjugated peptide [68 Ga]Ga-DOTA-K-A9 could detect a staphylococcal infection in vivo and distinguish it from aseptic inflammation. An optimized [68 Ga]Ga-DOTA-K-A9 synthesis omitting the use of acetone was developed, yielding 93 ± 0.9% radiochemical purity. The in vivo infection binding specificity of [68 Ga]Ga-DOTA-K-A9 was evaluated by micro positron emission tomography/magnetic resonance imaging of 15 mice with either subcutaneous Staphylococcus aureus infection or turpentine-induced inflammation and compared with 2-deoxy-2-[18 F]fluoro-D-glucose ([18 F]FDG). The scans showed that [68 Ga]Ga-DOTA-K-A9 accumulated in all the infected mice at injected doses ≥3.6 MBq. However, the tracer was not found to be selective towards infection, since the [68 Ga]Ga-DOTA-K-A9 also accumulated in mice with inflammation. In a concurrent in vitro binding evaluation performed with a 5-carboxytetramethylrhodamine (TAMRA) fluorescence analogue of the peptide, TAMRA-K-A9, the microscopy results suggested that TAMRA-K-A9 bound to an intracellular epitope and therefore preferentially targeted dead bacteria. Thus, the [68 Ga]Ga-DOTA-K-A9 uptake observed in vivo is presumably a combination of local hyperemia, vascular leakiness and/or binding to an epitope present in dead bacteria.

Prospective of 68Ga Radionuclide Contribution to the Development of Imaging Agents for Infection and Inflammation

During the last decade, the utilization of ⁶⁸Ga for the development of imaging agents has increased considerably with the leading position in the oncology. The imaging of infection and inflammation is lagging despite strong unmet medical needs. This review presents the potential routes for the development of ⁶⁸Ga-based agents for the imaging and quantification of infection and inflammation in various diseases and connection of the diagnosis to the treatment for the individualized patient management.

(68)Ga-labeled phage-display selected peptides as tracers for positron emission tomography imaging of Staphylococcus aureus biofilm-associated infections: Selection, radiolabelling and preliminary biological evaluation

INTRODUCTION

Staphylococcus aureus is a major cause of skin and deep-sited infections, often associated with the formation of biofilms. Early diagnosis and initiated therapy is essential to prevent disease progression and to reduce complications that can be serious. Imaging techniques are helpful combining anatomical with functional data in order to describe and characterize site, extent and activity of the disease. The purpose of the study was to identify and (68)Ga-label peptides with affinity for S. aureus biofilm and evaluate their potential as bacteria-specific positron emission tomography (PET) imaging agents.

METHODS

Phage-displayed dodecapeptides were selected using an in vitro grown S. aureus biofilm as target. One cyclic (A8) and two linear (A9, A11) dodecapeptides were custom synthesized with 1,4,7,10-tetraazacyclododecane-N,N',N″,N‴-tetraacetic acid (DOTA) conjugated via a lysine linker (K), and for A11 also a glycine-serine-glycine spacer (GSG). The (68)Ga-labeling of A8-K-DOTA, A9-K-DOTA, and A11-GSGK-DOTA were optimized and in vitro bacterial binding was evaluated for (68)Ga-A9-K-DOTA and (68)Ga-A11-GSGK-DOTA. Stability of (68)Ga-A9-K-DOTA was studied in vitro in human serum, while the in vivo plasma stability was analyzed in mice and pigs. Additionally, the whole-body distribution kinetics of (68)Ga-A9-K-DOTA was measured in vivo by PET imaging of pigs and ex vivo in excised mice tissues.

RESULTS

The (68)Ga-A9-K-DOTA and (68)Ga-A11-GSGK-DOTA remained stable in product formulation, whereas (68)Ga-A8-K-DOTA was unstable. The S. aureus binding of (68)Ga-A11-GSGK-DOTA and (68)Ga-A9-K-DOTA was observed in vitro, though blocking of the binding was not possible by excess of cold peptide. The (68)Ga-A9-K-DOTA was degraded slowly in vitro, while the combined in vivo evaluation in pigs and mice showed a rapid blood clearance and renal excretion of the (68)Ga-A9-K-DOTA.

CONCLUSION

The preliminary in vitro and in vivo studies of the phage-display S. aureus biofilm-selected (68)Ga-A9-K-DOTA showed desirable features for a novel bacteria-specific imaging agent, despite of relative fast blood degradation in vivo.

Evolving role of radiolabeled particles in detecting infection and inflammation, preliminary data with 99mTc-phytate in rats

PURPOSE

The aim of this study was to evaluate the ability of phytate radiolabeled with technetium-99m (Tc-phytate) to identify inflammatory processes.

MATERIALS AND METHODS

Radiolabeling efficiency analyses were carried out by thin-layer chromatography on silica gel strips, yielding a radiochemical purity of 92%. In addition, the partition coefficient of Tc-phytate, obtained in a mixture of n-octanol/water (1 : 1), showed hydrophilic features of the radiopharmaceutical. After Tc-phytate was administered into the tail vein of healthy and inflammation focus-bearing rats, induced, in the right tight, by zymosan suspension at 5% (w/v), blood clearance evaluation was performed and showed a short plasma half-life (2.7 min). In the inflammation focus-bearing rats, Tc-phytate scintigraphic images were obtained at 2, 4, and 8 h after radiotracer injection.

RESULTS

A significant radiopharmaceutical uptake was found in mononuclear phagocyte system organs (liver and spleen) and in the inflammation focus (compared with contralateral muscle). Histopathological analysis showed an intense mononuclear infiltration in the inflamed muscle, suggesting that macrophages may be responsible for the greater radiotracer uptake in the inflamed site. Furthermore, the target-to-nontarget ratio (%ID/g of inflamed muscle-to-%ID/g of control muscle ratio) obtained by scintigraphic images performed at 2 h after the radiotracer injection was 10.24±3.49, remaining without any significant difference at 4 and 8 h.

CONCLUSION

Inflammation focus was evident in the scintigraphic images from 2 to 8 h after Tc-phytate administration, suggesting that this radiopharmaceutical could be a potential alternative to identify inflamed regions.