Diagnosis Of Cyst Infection Research Articles

Standardized 4-point scoring scale of [18F]-FDG PET/CT imaging helps in the diagnosis of renal and hepatic cyst infections in patients with autosomal dominant polycystic kidney disease: a validation cohort.

Autosomal dominant polycystic kidney disease (ADPKD) is prone to multiple complications, including cyst infection (CyI). 2-Deoxy-2-[18F]fluoro-d-glucose positron emission tomography/computed tomography ([18F]-FDG PET/CT) imaging has proved useful in the diagnosis of renal and hepatic CyI. A 4-point scale comparing the uptake of [18F]-FDG in the suspected infected cyst versus the hepatic physiological background has been recently proposed. We performed an independent validation of this semi-quantitative scoring system. All ADPKD patients hospitalized between January 2009 and November 2019 who underwent an [18F]-FDG PET/CT for suspected CyI were retrospectively identified using computer-based databases. Medical files were reviewed. CyI was conventionally defined by the combination of fever (≥38°C), abdominal pain, increased plasma C-reactive protein levels (≥70mg/L), absence of any other cause of inflammation and favourable outcome after ≥21days of antibiotics. [18F]-FDG uptake of the suspected CyI was evaluated using a 4-point scale comparing the uptake of [18F]-FDG around the infected cysts with the uptake in the hepatic parenchyma. Statistics were performed using SAS version 9.4. Fifty-one [18F]-FDG PET/CT scans in 51 patients were included, of which 11 were cases of CyI. The agreement between the 4-point scale and the gold-standard criteria of CyI was significant [odds ratio of 6.03 for CyI in case of a score ≥3 (P = .014)]. The corresponding sensitivity, specificity, and positive and negative predictive values of [18F]-FDG PET/CT using the 4-point scale were 64% [Clopper-Pearson 95% confidence interval (CI) 30%-89%], 78% (95% CI 62%-89%), 44% (95% CI 20%-70%) and 89% (95% CI 73%-97%), respectively. Our independent validation cohort confirms the use of a semi-quantitative 4-point scoring system of [18F]-FDG PET/CT imaging in the diagnosis of CyI in patients with ADPKD. Considering its performance metrics with high specificity and negative predictive value, the scoring system is particularly useful to distinguish other causes of clinical inflammation than CyI and as such avoid unnecessarily long antibiotic treatment.

Standardized 4-point scoring scale of [18F]-FDG PET/CT imaging helps in the diagnosis of renal and hepatic cyst infections in patients with autosomal dominant polycystic kidney disease: A validation cohort

Autosomal dominant polycystic kidney disease (ADPKD) is prone to multiple complications, including cyst infection (CyI). [18F]-FDG PET/CT imaging proved useful in the diagnosis of renal and hepatic CyI. A 4-point scale comparing the uptake of [18F]-FDG in the suspected infected cyst versus the hepatic physiological background has been proposed. We performed an independent validation of this semi-quantitative scoring system. All ADPDK patients hospitalized between January 2009 and November 2019 who underwent an [18F]-FDG PET/CT for suspected CyI were retrospectively identified using computer-based databases. Medical files were systematically reviewed. CyI was conventionally defined by the combination of fever (> 38 °C), abdominal pain, increased plasma CRP levels (≥ 70 mg/L), absence of any other cause of inflammation, and favorable outcome after ≥ 21 days of antibiotics. [18F]-FDG uptake of the suspected CyI was evaluated using a 4-point scale comparing the uptake of [18F]-FDG around the infected cysts to the uptake in the hepatic parenchyma. Statistics were performed using SAS version 9.4. Fifty-one [18F]-FDG PET/CT scans in 51 patients were included, of which 11 cases of CyI. The agreement between the 4-point scale and the gold-standard criteria of CyI was significant, with an odds ratio of 6.03 for CyI in case of a score ≥ 3 ( P 0.014). The corresponding sensitivity and specificity of [18F]-FDG PET/CT using the 4-point scale were 63.6% and 77.5%, respectively. Our independent validation cohort confirms the use of a semi-quantitative 4-point scoring system of [18F]-FDG PET/CT imaging in the diagnosis of CyI in patients with ADPKD.

MO011: The Use of a 4-Point Scoring Scale in 18F-FDG-PET/CT Imaging Helps for Diagnosis of Renal and Hepatic CYST Infections in Patients with Autosomal Dominant Polycystic Kidney Disease: A Validation Cohort

Abstract BACKGROUND AND AIMS Autosomal dominant polycystic kidney disease (ADPKD) is prone to multiple complications, including cyst infection (CyI). 18F-FDG PET/CT imaging proved useful in the diagnosis of renal and hepatic CyI. A 4-point scale comparing the uptake of 18F-FDG in the suspected infected cyst versus the hepatic physiological background has been proposed. We performed an independent validation of this semi-quantitative score system. METHOD All ADPDK patients hospitalized between January 2007 and March 2019 who underwent an 18F-FDG PET/CT for suspected CyI were retrospectively identified using computer-based databases. Medical files were systematically reviewed. CyI was conventionally defined by: fever (>38°C), abdominal pain, increased plasma CRP levels (≥70 mg/dL), absence of any other cause of inflammation and favorable outcomes after ≥21 days of antibiotics. The 18F-FDG uptake around the suspected CyI was evaluated using the 4-point scale. Stats were performed using SAS version 9.4. RESULTS Our cohort included 51 18F-FDG PET/CT in 51 patients, including 11 cases of CyI according to the above-detailed definition. The agreement between the 4-point scale and the gold-standard criteria of CyI was significant, with an odds ratio of 6.03 for CyI in case of a score ≥3 (P, 0.014). The corresponding sensitivity and specificity of PET/CT using the 4-point scale were 63.3% and 77.5%, respectively. CONCLUSION Our independent validation cohort confirms that the use of a semi-quantitative 4-point scoring system helps in the diagnosis of CyI by 18F-FDG PET/CT imaging in patients with ADPKD.

The Use of a Visual Four-Score Scale Improves the Yield of 18F-FDG PET-CT Imaging in the Diagnosis of Cyst Infection in Patients with Autosomal Dominant Polycystic Kidney Disease

The Use of a Visual Four-Score Scale Improves the Yield of 18F-FDG PET-CT Imaging in the Diagnosis of Cyst Infection in Patients with Autosomal Dominant Polycystic Kidney Disease

La tomographie par émission de positons au 18F-FDG en pathologie rénale non oncologique : indications actuelles et perspectives

Positron emission tomography combined with computed tomography (PET/CT) is a nuclear imaging technique which provides anatomical and functional information. PET/CT is increasingly used in non-oncological nephrology since conventional radiological approaches after injection of contrast agents are relatively contra-indicated in patients with chronic kidney disease (CKD). PET/CT after i.v. injection of 18F-fluoro-deoxy-glucose (FDG) is not toxic and is characterized by a high sensitivity. The level of irradiation (∼5mSv) is acceptable. CKD does not significantly influence tissue uptake of 18F-FDG. The purpose of the present review aims at detailing the non-oncological indications of 18F-FDG PET/CT in general nephrology and after kidney transplantation. Particularly, 18F-FDG PET/CT appears useful in the diagnosis of cyst infection in patients with autosomal dominant polycystic kidney disease, as well as in the characterization of retroperitoneal fibrosis. In kidney transplant recipients, 18F-FDG PET/CT may help in the diagnostic work-up of suspected acute rejection, thereby eventually avoiding unnecessary kidney transplant biopsy. Perspectives in 18F-FDG PET/CT imaging are discussed, including innovative approaches of image analysis.

Diagnostic performance of [18F]fluorodeoxyglucose positron emission tomography–computed tomography in cyst infection in patients with autosomal dominant polycystic kidney disease

Cyst infection is a common complication of autosomal dominant polycystic kidney disease (ADPKD). Diagnosis is challenging with standard imaging techniques. We aimed to evaluate the diagnostic performance of [18F]fluorodeoxyglucose positron emission tomography–computed tomography (18-FDG PET–CT) for the diagnosis of cyst infections among ADPKD patients, in comparison with computed tomography (CT) and magnetic resonance imaging (MRI). All APKD patients who underwent 18-FDG PET–CT for suspected cyst infection between 2006 and 2013 in a French teaching hospital were included. Diagnosis of cyst infection was retained a posteriori on an index of clinical suspicion. 18-FDG PET–CT findings were was considered to be positive in cases of cyst wall hypermetabolism. CT or MRI findings were were considered to be positive in cases of cyst wall thickening (and enhancement if contrast medium was injected) and infiltration of the adjacent fat. A control group of ADPKD patients with 18-FDG PET–CT performed for other reasons was included. Thirty-two 18-FDG PET–CT scans were performed in 24 ADPKD patients with suspected cyst infection. A diagnosis of cyst infection was retained in 18 of 32 cases: 14 with positive 18-FDG PET–CT findings, and four false negatives. There were no false positives and no hypermetabolism of cyst walls in nine ADPKD control patients. 18-FDG PET–CT had a sensitivity of 77%, a specificity of 100%, and a negative predictive value of 77%. 18-FDG PET–CT allowed a differential diagnosis in three patients. In contrast, CT had a sensitivity of 7% and a negative predictive value of 35% (p <0.001 vs. 18-FDG PET–CT). Only eight MRI scans were performed. The diagnostic performance of 18-FDG PET–CT is superior to that of CT in cyst infections, for comparable radiation doses and with no injection of nephrotoxic contrast medium, in ADPKD patients.

Cyst infection in autosomal dominant polycystic kidney disease: causative microorganisms and susceptibility to lipid-soluble antibiotics

Cyst infection is a frequent and serious complication of autosomal dominant polycystic kidney disease (ADPKD). Lipid-soluble antibiotics like fluoroquinolones show good penetration into cysts and are recommended for cyst infection, but causative microorganisms are often resistant to these agents. This study investigated the profile of the microorganisms causing cyst infection in ADPKD, their susceptibility to lipid-soluble antibiotics, and clinical outcomes. This retrospective study reviewed all ADPKD patients admitted to Toranomon Hospital with a diagnosis of cyst infection from January 2004 to March 2014. All patients who underwent cyst drainage and had positive cyst fluid cultures were enrolled. Patients with positive blood cultures who satisfied our criteria for cyst infection or probable infection were also enrolled. There were 99 episodes with positive cyst fluid cultures and 93 episodes with positive blood cultures. The majority of patients were on dialysis. The death rate was high when infection was caused by multiple microorganisms or when there were multiple infected cysts. Gram-negative bacteria accounted for 74-79% of the isolates in all groups, except for patients with positive hepatic cyst fluid cultures. The susceptibility of Escherichia coli to fluoroquinolones was very low in patients with hepatic cyst infection, especially those with frequent episodes and those with hepatomegaly. Fungi were detected in two episodes. Fluoroquinolone-resistant microorganisms showed a high prevalence in cyst infection. It is important to identify causative microorganisms to avoid the overuse of fluoroquinolones and to improve the outcome of cyst infection in ADPKD.

Diagnosis of cyst infection in patients with autosomal dominant polycystic kidney disease: attributes and limitations of the current modalities

Cyst infection is a diagnostic challenge in patients with autosomal dominant polycystic kidney disease (ADPKD) because of the lack of specific manifestations and limitations of conventional imaging procedures. Still, recent clinical observations and series have highlighted common criteria for this condition. Cyst infection is diagnosed if confirmed by cyst fluid analysis showing bacteria and neutrophils, and as a probable diagnosis if all four of the following criteria are concomitantly met: temperature of >38°C for >3 days, loin or liver tenderness, C-reactive protein plasma level of >5 mg/dL and no evidence for intracystic bleeding on computed tomography (CT). In addition, the elevation of serum carbohydrate antigen 19-9 (CA19-9) has been proposed as a biomarker for hepatic cyst infection. Positron-emission tomography after intravenous injection of 18-fluorodeoxyglucose, combined with CT, proved superior to radiological imaging techniques for the identification and localization of kidney and liver pyocyst. This review summarizes the attributes and limitations of these recent clinical, biological and imaging advances in the diagnosis of cyst infection in patients with ADPKD.