Polycystic intrahepatic infection caused by Enterococcus casseliflavus: a case report and literature review.

BACKGROUND: Enterococcus casseliflavus is a rare pathogenic bacterium that is characterized by vancomycin resistance and can lead to multiple infections in the human body. This report describes a rare case of polycystic intrahepatic infection with E. casseliflavus which necessitated antibiotic treatment and surgical intervention involving cystic drainage. CASE PRESENTATION: A 59-year-old woman, a long-term hemodialysis patient, was hospitalized due to a 5-day history of fever, abdominal pain, and diarrhea, which were possibly caused by the ingestion of contaminated food. Her blood culture yielded a positive result for E. casseliflavus, and she was initially treated with piperacillin/tazobactam and linezolid. Later, the antibiotic regimen was adjusted to include meropenem and linezolid. Despite treatment, her body temperature remained elevated. However, subsequent blood cultures were negative for E.casseliflavus.Conventional CT scans and ultrasound examinations did not identify the source of infection. However, a PET-CT examination indicated an intrahepatic cyst infection. Following MRI and ultrasound localization, percutaneous intrahepatic puncture and drainage were performed on the 20th day. Fluoroquinolones were administered for 48 days. On the 32nd day, MRI revealed a separation within the infected cyst, leading to a repeat percutaneous drainage at a different site. Subsequently, the patient's temperature returned to normal. The infection was considered resolved, and she was discharged on the 62nd day. Follow-up results have been favorable thus far. CONCLUSIONS: Based on the findings from this case, it is recommended to promptly conduct PET-CT examination to exclude the possibility of intracystic infection in cases of polycystic liver infection that are challenging to control. Furthermore, timely consideration should be given to puncture drainage in difficult cases.

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.

Background: 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. Methods: 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 (≥70 mg/L), absence of any other cause of inflammation and favourable 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 with the uptake in the hepatic parenchyma. Statistics were performed using SAS version 9.4. Results: 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. Conclusions: 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.

Management of a Suspected Renal Cyst Infection With Intracystic Hemorrhage in a Patient With Autosomal Dominant Polycystic Kidney Disease.

Renal cyst infections are a serious complication in patients with autosomal dominant polycystic kidney disease (ADPKD). Cyst infections are challenging to treat and have a high incidence of complications such as sepsis and death. No guideline or evidence-based strategy for diagnosis or treatment of cyst infection currently exists. This lack of standardized guidance leads to individualized medical decision-making for each individual case, despite the high risk of morbidity and mortality associated with the infection. This case describes a 33-year-old female with a past medical history of ADPKD that presented with hematuria, increased urinary frequency, and left flank pain. On computed tomography (CT) imaging, she was found to have a large intracystic hemorrhage with an associated hematoma formation. Laboratory evaluation was remarkable for leukocytosis with left shift but normal renal function. Urinalysis displayed hematuria and the presence of protein, but the culture resulted in no growth. In the presence of clinical signs of infection, she was suspected to have an infected renal cyst that did not have glomerular communication, given the bland urinalysis and negative urine culture. Her hemoglobin stabilized, and she did not require embolization or percutaneous drainage of the cyst. Intravenous levofloxacin was initiated, and the patient clinically improved with the normalization of leukocytosis. Blood cultures remained negative, and she was discharged to home with a course of oral levofloxacin with a resolution of symptoms.

Microbiome of infected cysts, feces and saliva in patients with autosomal dominant polycystic kidney disease.

Cyst infection is a frequent and serious complication of autosomal dominant polycystic kidney disease (ADPKD). Hematogenous spread via bacterial translocation in the intestine is considered to be the main cause, so intestinal flora may be involved. However, the exact role of the intestinal flora in cyst infection in ADPKD is unknown. We report a 66-year-old woman and a 56-year-old man with ADPKD who had severe hepatic cyst infection. We analyzed the microbiome of infected cyst content, feces, and saliva in these two patients. The microbiome of patient 1 showed various bacteria in an infected cyst, whereas that of patient 2 showed only one bacterium. In both patients, the composition of the microbiome of the cyst content was quite different from those of feces and saliva, and the main bacteria in the infected cyst content represented a small proportion of those in feces and saliva. Lactobacilli were not almost detected in the infected cyst content though some lactobacilli are endemic in the gastrointestinal tract and the saliva. The association between bacteria in cysts and those in feces or saliva remains uncertain, and further research on this topic is needed.

Hepatic Cyst Infection Following Recurrent Biliary Obstruction in Polycystic Liver Disease.

An 89-year-old man with polycystic liver disease (PCLD) received uncovered self-expandable metallic stent (SEMS) placement above the papilla for malignant biliary obstruction caused by cholangiocarcinoma. He developed cholangitis ten months later due to SEMS occlusion caused by tumor ingrowth, and 2 plastic biliary stents were placed inside the SEMS across the papilla. Fever and right costal pain appeared two weeks after reintervention. Suspecting hepatic cyst infection based on imaging studies, percutaneous transhepatic cyst drainage was performed. Increased inflammatory cells and the presence of pathogens in the cyst fluid led to a definitive diagnosis of hepatic cyst infection. Following drainage, the hepatic cyst shrank with resolution of the symptoms. SEMS occlusive-related cholangitis or retrograde infection due to duodenal-biliary reflux after reintervention was considered as the cause of the hepatic cyst infection. Careful clinical and imaging evaluation should be performed in patients with PCLD undergone biliary stenting, because cyst infection may occur following stent occlusion or subsequent biliary reintervention.

The Importance of Radiologic Imaging Modalities in Autosomal Dominant Polycystic Kidney Disease.

Autosomal dominant polycystic kidney disease (ADPKD) is a common disorder that occurs in approximately one in 1000 live births. Patients may be asymptomatic or present with symptoms such as hypertension, hematuria, proteinuria, or renal function impairment. It can present with extra renal complications like cerebral aneurysms, hepatic and pancreatic cysts, infected cysts, cardiac valve disease, colonic diverticula, abdominal wall and inguinal hernia, and seminal vesicle cyst. Imaging studies such as ultrasonography (US), computed tomography (CT), and magnetic resonance imaging (MRI) provide vital information regarding the diagnosis of the disease, monitoring of the progression of the disease, and detection of complications from the disease. We present the case of a 40-year-old male who developed extra-renal complications, and how different imaging modalities facilitated and enabled us to optimize the care of this patient in a timely manner.

First case of a renal cyst infection caused by Desulfovibrio: a case report and literature review.

BACKGROUND: Genus Desulfovibrio species is a sulphate-reducing anaerobic gram-negative rod that resides in the human oral cavity and intestinal tract. It was reported as the causative pathogen of bacteraemia and abdominal infections, but not renal cyst infection, and Desulfovibrio fairfieldensis has higher pathogenicity than other Desulfovibrio species. CASE PRESENTATION: A 63-year-old man was on haemodialysis for end-stage renal failure due to autosomal dominant polycystic kidney disease. On admission, he had a persistent high-grade fever, right lumbar back pain, and elevated C-reactive protein levels. His blood and urine cultures were negative. He received ciprofloxacin and meropenem; however, there was no clinical improvement. Contrast-enhanced computed tomography and plain magnetic resonance imaging revealed a haemorrhagic cyst at the upper pole of the right kidney. The lesion was drained. Although the drainage fluid culture was negative, D. fairfieldensis was detected in a renal cyst using a polymerase chain reaction. After the renal cyst drainage, he was treated with oral metronidazole and improved without any relapse. CONCLUSIONS: To the best of our knowledge, this is the first reported case of a renal cyst infection with Desulfovibrio species. D. fairfieldensis is difficult to detect, and polymerase chain reaction tests can detect this bacterium and ensure better management for a successful recovery.

Incidence, Risk Factors and Outcomes of Kidney and Liver Cyst Infection in Kidney Transplant Recipient With ADPKD.

Introduction: Cyst infection is a known complication of autosomal dominant polycystic kidney disease (ADPKD). Here, we describe incidence, risk factors, clinical presentation, and outcomes of cyst infection in kidney transplant recipient. Methods: We conducted a single-center retrospective cohort study of patients with ADPKD with renal allografts between January 1, 2009, and October 31, 2020. Cyst infection diagnosis was based on previously described clinical and radiological criteria, using positron emission tomography when available. Results: A total of 296 patients with ADPKD with renal allografts were included, and 21 patients experienced 22 episodes of cyst infection over a median follow-up of 4 (2-7) years. The cumulative incidence rate was 3% at 1 year, 6 % at 5 years, and 12% at 10 years after transplantation. In multivariate analysis, history of cyst infection before transplantation was the only significant risk factor identified to predict the occurrence of cyst infection after kidney transplantation (hazard ratio [HR] 3.47, 95% CI 1.29-9.31). The clinical presentation at diagnosis of cyst infection included isolated fever in 5 (23%) episodes, acute kidney injury in 12 (55%), and severe sepsis/septic shock in 3 (14%) episodes. Among the 16 (73%) episodes with culture positivity, Escherichia coli was the most common pathogen. There was no difference between early (≤1 year after transplantation) and late (>1 year) cyst infection episodes in terms of clinical presentation and outcomes. Cyst infection was significantly associated with graft loss (HR 3.93, 95% CI 1.21-12.80), but no causal relationship could be established. Conclusion: Incidence of cyst infection in ADPKD after kidney transplantation is low, history of cyst infection representing the main risk factor.

Repetitive Refractory Renal Cyst Infection in Autosomal Dominant Polycystic Kidney Disease for which Renal Transcatheter Arterial Embolization Was Effective in Preventing Recurrence.

Renal cyst infection is a frequent and serious complication of autosomal dominant polycystic kidney disease (ADPKD) that is often difficult to treat and can be fatal. While nephrectomy is the standard therapy for severe refractory renal cyst infection, it can be associated with severe adverse events. We experienced a case of repetitive renal cyst infection in a 58-year-old Japanese man with ADPKD on dialysis. He underwent renal transcatheter arterial embolization (TAE) four months after the last episodes of renal cyst infection, and his renal cyst infection has not recurred since renal TAE. This case suggested that renal TAE is effective for preventing repetitive renal cyst infection.

Case Report: Liver Cysts and SARS-CoV-2: No Evidence of Virus in Cystic Fluid.

Background: In December 2019, an outbreak of pneumonia, caused by a new type of coronavirus, named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It quickly spread worldwide, resulting in a pandemic. The clinical manifestations of SARS-CoV-2 range from mild non-specific symptoms to severe pneumonia with organ function damage. In addition, up to 60% of patients have liver impairment or dysfunction, confirmed by several studies by the presence of SARS-CoV-2 in the liver tissue. Methods: We report two cases of symptomatic liver cyst requiring fenestration after recent SARS-CoV-2 infection. Both patients had hospital admission due to documented SARS-CoV-2 infection. Recently, after the infection, they developed symptoms caused by an enlarged hepatic cyst: one had abdominal pain, and the other had jaundice. They underwent surgery after two negative swab tests for SARS-CoV-2. Results: Cystic fluid was sent for microbiological test, and real-time fluorescence polymerase chain reaction COVID-19 nucleic-acid assay of the cyst fluid was found to be negative in both cases. Discussion: Although there are no current data that can document a viral contamination of cystic fluid, there are data that document a hepatotropism of COVID-19 virus. Herein we report that after viral clearance at pharyngeal and nasal swab, there is no evidence of viral load in such potential viral reservoir.

Modified Sistrunk procedure in a pediatric population: Infected thyroglossal duct cysts as a risk factor for recurrence and review of the literature.

AIM: To analyze the rate of recurrence and possible risk factors after surgical treatment in pediatric patients with thyroglossal ductus cyst (TGDC), who underwent the Modified Sistrunk Procedure (MSP). DESIGN: Retrospective study. INSTITUTION: The pediatric otorhinolaryngology clinic of a university. MATERIALS AND METHODS: The study included a total of 251 pediatric patients aged between 2 and 17 years, whose histopathological diagnosis was confirmed and who underwent MSP due to TGDC over a period of 10 years from January 2009 to December 2019. The chi-square test was used to determine the relationship between the independent variables and the dependent variables. Parameters used in the study: The parameters were age, gender, the history of infected TGDC before surgery (cellulitis, abscess), incision and drainage in patients with abscess, number of cysts detected in ultrasonographic imaging, postoperative histopathology, and the number of recurrences. RESULTS: The study included a total of 251 pediatric patients. The mean age of the children was 6.2 years (2-17 years), the mean follow-up period was 4.8 years (2-6 years), and 38 (15.13%) recurrences were observed after 251 MSP applications. Five risk factors were found to be statistically significant in terms of recurrence rates (p<0.05). These risk factors were surgery during the school period (6-10 years), history of infected TGDC, abscess formation, incision/drainage before MSP, and multicystic cyst in ultrasonographic evaluation. CONCLUSION: The main determinant for the five significant risk factors among the causes of MSP recurrence is a history of infected TGDC before surgery. When there is no history of TGDC infection in pediatric patients before surgery, surgery should be planned under appropriate conditions before infection occurs. The risk of infected TGDC, cellulitis, and abscess formation increases at school age in particular due to frequent upper respiratory tract infections. When there is a cyst infection, antibiotic treatment should be applied, and incision and drainage should be avoided as much as possible in the presence of an abscess.

A case of autosomal dominant polycystic kidney disease with amelioration of refractory cyst infections following prolonged hemodialysis time.

Renal cyst infection is a frequent and serious problem in patients with autosomal dominant polycystic kidney disease (ADPKD). Cyst infection is often a refractory complication of treatment that leads to sepsis and death in patients with ADPKD. It was previously reported that a higher dose of dialysis demonstrated clearly better survival than shorten-time dialysis. The relationship between the frequency of cyst infection episodes in hemodialysis (HD) patients with ADPKD and the dialysis dose has not yet been fully elucidated. In this report, we describe a case of an HD patient with ADPKD that was provided elongation of HD time from 4-h twice weekly HD to 8-h thrice weekly nocturnal HD. As a result, the frequency of cyst infection episodes decreased from 10.0 to 1.5 days a month. Our findings suggest that prolonged HD time might contribute to amelioration of refractory cyst infections in patients with ADPKD.

PET/CT Imaging for Personalized Management of Infectious Diseases.

Positron emission tomography combined with computed tomography (PET/CT) is a nuclear imaging technique which is increasingly being used in infectious diseases. Because infection foci often consume more glucose than surrounding tissue, most infections can be diagnosed with PET/CT using 2-deoxy-2-[18F]fluoro-D-glucose (FDG), an analogue of glucose labeled with Fluorine-18. In this review, we discuss common infectious diseases in which FDG-PET/CT is currently applied including bloodstream infection of unknown origin, infective endocarditis, vascular graft infection, spondylodiscitis, and cyst infections. Next, we highlight the latest developments within the field of PET/CT, including total body PET/CT, use of novel PET radiotracers, and potential future applications of PET/CT that will likely lead to increased capabilities for patient-tailored treatment of infectious diseases.

The use of a visual 4-point scoring scale improves the yield of 18F-FDG PET-CT imaging in the diagnosis of renal and hepatic cyst infection in patients with autosomal dominant polycystic kidney disease.

PURPOSE: [18F]FDG PET/CT (PET/CT) proved useful in the diagnosis of renal and hepatic cyst infection (CyI) in patients with autosomal dominant polycystic kidney disease (ADPKD). However, the definition of CyI by PET/CT is unclear. Here, we characterize the [18F]FDG uptake in CyI in order to infer a visual 4-point diagnostic scale. METHODS: All ADPKD patients hospitalized between 2007 and 2019 for suspected CyI and who underwent an [18F]FDG PET/CT scan were listed. CyI was defined by 5 concomitant criteria: fever ≥ 38 °C; abdominal pain; peak plasma CRP ≥ 70 mg/L; no other cause of inflammation; and favorable outcomes after antibiotics for ≥ 21 days. First, all PET/CT images were visually interpreted. Next, the [18F]FDG uptake around the suspected CyI was scored using a semiquantitative 4-point scale in comparison to blood and liver activities. RESULTS: Sixty [18F]FDG PET/CT scans were performed for suspected CyI in 38 ADPKD patients. Twenty-nine episodes met the gold-standard criteria for CyI. The visual assessment of PET/CT images reached a sensitivity of 73.1% and a specificity of 70.6%. Using the 4-point scale, an [18F]FDG score ≥ 3 (i.e., cyst uptake > liver) improved the specificity to 85.3%. CONCLUSION: [18F]FDG PET-CT is helpful in CyI diagnosis in ADPKD, and the use of a 4-point scoring of [18F]FDG uptake improves its diagnostic yield, with positive and negative predictive values of 78.3 and 78.4%, respectively. External validation is required.

Huge solitary-infected liver cyst successfully managed by deroofing operation to remove 3.8 l of pus.

Simple liver cysts are usually asymptomatic, and complications are uncommon. However, infection of cysts can very occasionally occur, and this troublesome complication requires treatment. An 87-year-old woman admitted for dyspnea, abdominal discomfort, fever, and mild icterus underwent ultrasonographic (US) and computed tomography (CT) examinations, and a huge cystic lesion was identified in the right hepatic lobe. The diagnosis of an infected gigantic liver cyst was made by abdominal CT and percutaneous transhepatic drainage under ultrasonographic guidance. The pus viscosity was so high that pus drainage was ineffective. Bacterial culture was positive for Klebsiella pneumoniae. The cyst diameter was approximately 21 cm, and the total pus discharge was 3.8 l. Emergency operation to fenestrate the cyst wall relieved the patient's critical condition. This report is clinically significant because 3.8 l of pus may be one of the largest reported quantity of drained pus from an infected cyst. We found no reports of > 3.8 l of drained pus in an English literature search. It is also very rare that imaging identified postoperative liver regeneration filling the huge empty space previously occupied by the cyst. Large liver cysts in older people should be carefully followed, preparing for the rare possibility of infection.

Cyst infection in autosomal dominant polycystic kidney disease: our experience at Toranomon Hospital and future issues.

Cyst infection is a frequent and serious complication of autosomal dominant polycystic kidney disease (ADPKD) that is often difficult to treat and can be fatal. However, much is still unknown about cyst infection. Positron emission tomography (PET) is generally recommended for detecting infected cysts, but it has the disadvantages of limited availability, high cost, and radiation exposure. We have devised magnetic resonance imaging (MRI) diagnostic criteria for cyst infection. Lipid-soluble antibiotics such as fluoroquinolones show good penetration into cysts and are recommended for cyst infection. However, we reported that fluoroquinolone-resistant microorganisms showed a high prevalence in cyst infection. We should, therefore, reconsider the empirical use of fluoroquinolones for ADPKD patients with cyst infection. We have suggested a new antibiotic strategy according to the severity of cyst infection. It may be important to consider the drug half-life in serum in addition to the drug susceptibility when selecting antibiotics Cyst drainage is necessary for some patients with refractory cyst infection; however, cyst drainage can be associated with severe adverse events. We suggest adaptation criteria for cyst drainage in patients with cyst infection in ADPKD. Most causative bacteria of cyst infection are enterobacteria, and hematogenous spread via bacterial translocation in the intestine is considered the main cause of cyst infection. Therefore, intestinal flora may be important for cyst infection. The role of the intestinal flora in cyst infection in ADPKD is unknown and should be explored in future research.

Delayed bleeding complication due to internal mammary artery injury after ultrasound-guided percutaneous catheter drainage for liver cyst infection.

BACKGROUND: Ultrasound-guided percutaneous catheter drainage (PCD) is widely accepted as a primary treatment for pyogenic liver abscess. Severe PCD-related complications have been reported; however, delayed bleeding complications due to internal mammary artery injury are unknown. CASE PRESENTATION: An 84-year-old man undergoing hemodialysis owing to chronic kidney disease due to focal segmental glomerulosclerosis was admitted to our hospital for liver cyst infection. Ultrasound-guided PCD was carried out through the normal liver at the upper abdominal midline at the level of the sixth intercostal space. Two days later, an abdominal hematoma occurred at the puncture site. Contrast-enhanced computed tomography revealed extravasation of the distal right internal mammary artery, which was successfully treated with percutaneous coil embolization. CONCLUSION: Internal mammary artery injury should be considered as a differential diagnosis when a progressing hematoma develops after PCD.

18F-FDG PET/CT in cyst infection in autosomal dominant polycystic kidney disease.

Infection of a cyst within an autosomal dominant polycystic kidney disease (ADPKD) is a serious complication. Diagnosis with conventional imaging techniques such as ultrasonography, computed tomography (CT), and magnetic resonance imaging can be sometimes challenging. The definite diagnosis is analysis of the cyst fluid, but cyst punctures can cause bleeding, rupture, and contamination of adjacent cysts. Recently, FDG PET/CT has been reported as a sensitive tool for detection of cyst infection. We describe a case of 63-year-old woman with infected cysts in the left kidney, in whom accurate diagnosis was made on FDG PET/CT. FDG PET/CT is an important investigation in patients with fever of uncertain etiology, where renal cyst infection is a possible cause, but other etiologies also need to be ruled out.

Mediastinal cyst infection followed by bacteremia due to Streptococcus anginosus after endobronchial ultrasound-guided transbronchial needle aspiration.

We herein report a case of recurrent mediastinal cyst infection followed by bacteremia after endobronchial ultrasound-guide transbronchial needle aspiration (EBUS-TBNA). A 65-year-old Japanese male with sarcoidosis presented with 4 L progressive lymph node adenopathy and was diagnosed with mediastinal cyst by EBUS-TBNA. After bronchoscopy, he suffered from a high fever. Chest computed tomography showed enlargement of the 4 L lymph node with low attenuation areas, the elevation of mediastinal fat concentration. Blood cultures were positive for Streptococcus anginosus. Antimicrobial agents were administered for a total of 12 weeks, at which point the size of the lymph node was reduced. However, at 5 months after the discontinuation of antimicrobial agents, the mediastinal cyst infection recurred. It is important to conduct careful follow-up because mediastinal cyst infection following ebus-tbna may relapse with conservative treatment without invasive surgery.