Positron emission tomography in the diagnostic pathway for intracystic infection in adpkd and "cystic" kidneys. a case series

Efficacy of 18F-Fluorodeoxyglucose positron emission tomography/computed tomography for detecting renal cell carcinoma in patients with end-stage renal disease

PURPOSE

Dialysis patients are at an increased risk of developing renal cell carcinoma (RCC); however, differentiating between RCC and benign cysts can sometimes be difficult using modalities, such as computed tomography (CT) and ultrasonography. 18F-Fluorodeoxyglucose positron emission tomography (FDG-PET)/CT efficiently detects malignant tumors; however, physiological accumulation of FDG in the kidney limits its efficacy in detecting renal tumors. However, in patients with severely impaired renal function, the renal accumulation of FDG is decreased, possibly improving the detection of renal malignancies in this patient population. This study evaluated the usefulness of FDG-PET/CT as a screening tool for detecting RCC in patients with end-stage renal disease.

MATERIALS AND METHODS

This prospective study recruited 150 participants from 2012 to 2016 who were on dialysis or underwent renal transplantation and were on dialysis until transplantation. FDG-PET/CT was performed to screen for RCC. Three radiologists independently evaluated the images. No protocol was defined for the additional management of positive examinations, leaving decisions to the discretion of each participant. Negative examinations were observed until the end of 2019.

RESULTS

In total, 150 participants (mean age, 58 ± 13 years; 105 men) underwent FDG-PET/CT. Twenty patients (13.4%) were diagnosed as positive. Fifteen patients underwent additional examinations and/or procedures, and RCC was found in seven patients. Of the four patients who underwent surgical resection, the pathological results were clear cell RCC in one, papillary RCC in one, and acquired cystic disease-associated RCC in two. Two participants were diagnosed with RCC on bone biopsy, and one was diagnosed on dynamic CT but opted for observation. The sensitivity, specificity, and negative predictive value were 100%, 93.9%, and 100%, respectively.

CONCLUSION

FDG-PET/CT was useful for detecting RCC in patients with end-stage renal disease. Our findings show the potential use of FDG-PET/CT as a screening tool for RCC in this patient population.

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.

EASL Clinical Practice Guidelines on the management of cystic liver diseases

The advent of enhanced radiological imaging techniques has facilitated the diagnosis of cystic liver lesions. Concomitantly, the evidence base supporting the management of these diseases has matured over the last decades. As a result, comprehensive clinical guidance on the subject matter is warranted. These Clinical Practice Guidelines cover the diagnosis and management of hepatic cysts, mucinous cystic neoplasms of the liver, biliary hamartomas, polycystic liver disease, Caroli disease, Caroli syndrome, biliary hamartomas and peribiliary cysts. On the basis of in-depth review of the relevant literature we provide recommendations to navigate clinical dilemmas followed by supporting text. The recommendations are graded according to the Oxford Centre for Evidence-Based Medicine system and categorised as 'weak' or 'strong'. We aim to provide the best available evidence to aid the clinical decision-making process in the management of patients with cystic liver disease.

Role of Fluorodeoxyglucose-PET in Interventional Radiology

Fluorodeoxyglucose (FDG)-PET has expanding applications in the field of interventional radiology. FDG-PET provides both qualitative and quantitative assessments of malignancy, infection, and inflammation. These assessments can assist interventional radiologists in selecting the most appropriate treatment options for their oncology patients. FDG-PET is also useful for evaluating the response to interventional treatments and in predicting the prognosis of oncology patients. Finally, FDG-PET can assist the interventional radiologist in diagnosing and monitoring response to treatment of infection and inflammation. Nevertheless, there is a need for additional prospective studies to further establish the role of FDG-PET in these applications.

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.

FDG PET/CT for Detection of Infectious Complications Following Solid Organ Transplantation

Infectious complications after solid organ transplantation (SOT) are often more severe and remain a diagnostic challenge due to vague and atypical clinical presentations. Diagnostic performance of conventional diagnostic tools is frequently inadequate which may lead to delayed diagnosis with the risk of poorer outcomes. This literature review aimed to investigate the current evidence on the use of ¹⁸F-fluoro-deoxy-glucose (FDG) Positron Emission Tomography (PET)/computer tomography (CT) in infectious complications after SOT. Based on search in PubMed, Medline, and Cochrane databases, 13 articles and 46 case reports were included. For inclusion, articles were to include data on patients with infectious complications after SOT, and where FDG PET/CT was part of the work-up. Final searches were conducted on 02 September 2020. Overall, in the absence of initial diagnostic clues, FDG PET/CT should be considered as the imaging technique of choice as it may guide further investigations and eventually reveal the diagnosis in most of the patients. However, the available literature of the role of FDG PET/CT in SOT recipients with infectious complications is scarce and well-designed prospective studies including control groups are warranted to establish the role of FDG PET/C/ in SOT recipients. The main drawback of FDG PET/CT is the lack of ability to differentiate between cancer and infectious diseases which are both highly prevalent in this patient group. Accordingly, the main reasons for "false" results of FDG PET/CT is the misdiagnosis of cancer in benign inflammatory or infectious processes, information which nonetheless can be useful.

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.

In-hospital management of acute complicated urinary tract infections

Upper tract urinary tract infections that require hospitalization have been the focus of national recommendations in 2018 by the French society of infectious diseases (Spilf). We here propose to discuss several complex-challenging situations: severe infection with sepsis, pyelonephritis in the pregnant woman, management of infections involving multiresistant bacteria and infection in polycystic kidney disease.

[18F-FDG positron emission tomography in non-oncological renal pathology: Current indications and 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.

Infected cyst in patients with autosomal dominant polycystic kidney disease: Analysis of computed tomographic and ultrasonographic imaging features

Purpose

To investigate the imaging features of cyst infection in autosomal dominant polycystic kidney disease (ADPKD) patients using computed tomography (CT) and ultrasonography (US).

Materials & methods

The institutional review board approved this retrospective study. Fifty-one episodes with proven cyst infection in forty-three ADPKD patients were included. Two experienced abdominal radiologists reviewed CT and US images and evaluated the following imaging features in consensus: cyst size, location, cyst shape, intracystic attenuation, intracystic echogenicity, intracystic heterogeneity, wall thickness, the presence of fluid-fluid level, septation, intracystic gas, pericystic fat infiltration, and pericystic hyperemia. Intracystic attenuation was measured for all infected cysts and two presumed normal cysts and compared using the Wilcoxon rank-sum test.

Results

On CT scans, the median size of infected cysts was 5.5 cm (range: 2.3–18.8 cm) and 46 of 51 (90.2%) infected cysts were located in the subcapsular region. Most (48 of 51, 94.1%) infected cysts showed lobulated, focal bulging or irregular shape. Discernible wall thickening (84.1%) was the most frequently found imaging feature of infected cysts followed by relatively higher intracystic attenuation compared to normal cysts (79.1%) and pericystic fat infiltration (52.9%). Fluid/fluid level was found in 3 of 51 (5.9%) infected cysts and intracystic gas was found in 3 of 51 (5.9%) infected cysts, respectively. For hepatic cysts, 11 of 14 (78.6%) infected cysts showed pericystic hyperemia. Intracystic attenuation was significantly higher in infected cysts (median; 19.0 HU) than in presumed normal cysts (median; 8.5 HU) (P<0.001), and exceeded 25 HU in 18 (35.3%) of 51 infected cysts. Among the 41 infected cysts for which US images were available, 35 (85.1%) showed heterogeneous echogenicity.

Conclusion

Minute imaging features such as minimal wall thickening or relatively high attenuation compared to normal cysts would be helpful to detect infected cysts in ADPKD patients.

18F-FDG PET/CT in Autosomal Dominant Polycystic Kidney Disease Patients with Suspected Cyst Infection

The objective of this study was to determine the value of ¹⁸F-FDG PET/CT for diagnosing renal or hepatic cyst infection in patients with autosomal dominant polycystic kidney disease (ADPKD). Methods: This retrospective, single-center study included all patients who had ADPKD and underwent ¹⁸F-FDG PET/CT because of suspected cyst infection between 2010 and 2017. Results: Thirty ¹⁸F-FDG PET/CT scans of 30 individual patients were included; 19 of them had positive results for cyst infection. According to a previously established clinical and biochemical reference standard, ¹⁸F-FDG PET/CT achieved a sensitivity of 88.9%, a specificity of 75.0%, a positive predictive value of 84.2%, and a negative predictive value of 81.8% for the diagnosis of cyst infection. In 5 cases, ¹⁸F-FDG PET/CT suggested that the symptoms could be explained by a different pathologic process, including pneumonia (n = 1), generalized peritonitis (n = 1), pancreatitis (n = 1), colitis (n = 1), and cholangitis (n = 1). The total duration of the hospital stay and the duration between the ¹⁸F-FDG PET/CT scan and hospital discharge for patients with ¹⁸F-FDG PET/CT scan results that were positive for cyst infection were significantly longer than those for patients with negative scan results (P = 0.005 and P = 0.009, respectively). Creatinine levels were significantly higher in patients with ¹⁸F-FDG PET/CT scan results that were positive for cyst infection than in patients with negative scan results (P = 0.015). Other comparisons of clinical parameters (age, sex, presence of fever [>38.5°C] for more than 3 d, abdominal pain, history of solid-organ transplantation and nephrectomy, and immune status), laboratory values (C-reactive protein level, leukocyte count, and estimated glomerular filtration rate), and microbiologic test results (blood and urine cultures) were not significantly different (P = 0.13-1.00) in patients with positive and negative ¹⁸F-FDG PET/CT scan results. Conclusion: ¹⁸F-FDG PET/CT is a useful imaging modality for the evaluation of patients with ADPKD and suspected cyst infection.

FDG-PET/CT for diagnosis of cyst infection in autosomal dominant polycystic kidney disease

Purpose

Cyst infections are a common complication in autosomal dominant polycystic kidney disease (ADPKD). Diagnosing these infections often remains challenging. Conventional imaging techniques such as ultrasonography, computed tomography (CT), and standard magnetic resonance imaging have several drawbacks and disadvantages. The purpose of this pictorial essay was to illustrate and discuss the potential value of ¹⁸F-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET)/CT in diagnosing cyst infection in ADPKD.

Methods

Exemplary (ADPKD) patients who underwent FDG-PET/CT as part of their routine clinical work-up in our institution are presented to show the potential value and drawbacks of this imaging technique in diagnosing cyst infection. In addition, the current literature and guidelines on this topic were reviewed.

Results

FDG-PET/CT appears to be a sensitive method for the detection of cyst infection, but it is not infallible. Furthermore, FDG uptake in cysts and cyst-like lesions is not specific and clinical and radiological correlations are essential to improve specificity and minimize the risk of falsely discarding other diseases, in particular malignancy.

Conclusion

FDG-PET/CT seems to be a useful imaging modality to diagnose cyst infections in ADPKD. However, its exact diagnostic value has not been established yet due to the lack of a reliable reference standard in previous studies on this topic.

The Role of PET Scanning in the Evaluation of Patients With Kidney Disease

Patients with underlying kidney disease are often required to undergo imaging for a variety of purposes including diagnosis and prognosis. A test that is being increasingly used with for this group of patients is the positron emission test (PET) scan. In addition, combining the nuclear medicine technique (PET) with computed tomography scan allows additional imaging advantages over either alone. These imaging modalities are commonly used for a number of extrarenal indications (ie, cancer, coronary artery disease, central nervous system disease, infectious diseases, and others). They have also been used for diagnosis of acute tubulointerstitial nephritis, evaluation and management of retroperitoneal fibrosis, identifying infection within kidney and liver cysts, and distinguishing complex kidney cysts from kidney cancer in patients with underlying CKD. We will review PET scan utility in patients with kidney disease.

Diagnostic Algorithm in the Management of Acute Febrile Abdomen in Patients with Autosomal Dominant Polycystic Kidney Disease

Background

Acute febrile abdomen represents a diagnostic challenge in patients with autosomal dominant polycystic kidney disease (ADPKD). Although criteria have been proposed for cyst infection (CyI) and hemorrhage (CyH), there is a lack of comparative assessments. Furthermore, distinguishing cystic from non-cystic complications remains problematic.

Design

ADPKD patients presenting with abdominal pain and/or fever between 01/2005 and 06/2015 were retrospectively identified in a systematic computerized billing database. CyH was defined as spontaneous intracystic density above 50 Hounsfield units on computed tomography (CT). CyI was definite if confirmed by cyst puncture, and probable if 4 criteria were met: 3-day fever, loin/liver tenderness, C-reactive protein (CRP) plasma levels >50mg/L and no CT evidence for CyH. Other episodes were grouped as inflammation of unknown origin (IUO).

Results

Among a cohort of 173 ADPKD patients, 101 presented with 205 episodes of abdominal pain (n = 172) and/or fever (n = 33). 20 patients experienced 30 CyH, whereas 16 presented 23 episodes of definite (n = 11) or probable (n = 12) CyI. 35 IUO were observed in 31 patients. Clinically, fever was observed in 7% vs. 100% vs. 66% of CyH, CyI and IUO, respectively. Biologically, CRP cut-off at 70 mg/dl showed 92% sensitivity and 81% specificity in CyI diagnosis. Urine or blood cultures remained sterile in >90% of CyH, but were contributive in 53.4% of CyI and IUO, with a 74.2% prevalence for E. coli. Radiologically, ultrasounds, CT and magnetic resonance diagnosed CyI in 2.6%, 20% and 16.7% of cases, respectively. ¹⁸F-FDG positron-emission tomography (PET)/CT was done within a median period of 7 days post antibiotics, and significantly changed patient management in 71.4%.

Conclusions

This retrospective single-center series underscores the usefulness of clinical–fever–and biological–CRP–parameters, but emphasizes the limitations of bacteriological and radiological investigations in cases of acute febrile abdomen in ADPKD patients. ¹⁸F-FDG-PET/CT imaging may be helpful in such condition.

Diagnostic performance of [(18)F]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 [(18)F]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.

Autosomal-dominant polycystic kidney disease (ADPKD): executive summary from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

Autosomal-dominant polycystic kidney disease (ADPKD) affects up to 12 million individuals and is the fourth most common cause for renal replacement therapy worldwide. There have been many recent advances in the understanding of its molecular genetics and biology, and in the diagnosis and management of its manifestations. Yet, diagnosis, evaluation, prevention, and treatment vary widely and there are no broadly accepted practice guidelines. Barriers to translation of basic science breakthroughs to clinical care exist, with considerable heterogeneity across countries. The Kidney Disease: Improving Global Outcomes Controversies Conference on ADPKD brought together a panel of multidisciplinary clinical expertise and engaged patients to identify areas of consensus, gaps in knowledge, and research and health-care priorities related to diagnosis; monitoring of kidney disease progression; management of hypertension, renal function decline and complications; end-stage renal disease; extrarenal complications; and practical integrated patient support. These are summarized in this review.

[Infectious complications in autosomal dominant polycystic kidney disease]

Despite advances in the management of autosomal dominant polycystic kidney disease over the past two decades, infection of liver and kidney cysts remains a serious and potentially threatening complication. Kidney cyst infection is the most frequent complication. It is differentiated from hemorrhage by the clinical presentation (mainly the severity and duration of fever), C-reactive protein (CRP) and white blood cells levels, and the density of the suspected cyst on computed tomography. Liver cyst infection occurs more frequently in patients with large cysts volumes. It can be life threatening and has a tendency to recur. In both infections, the best radiological imaging technique is positron emission tomography after intravenous injection of [18F]-fluorodeoxyglucose combined with computed tomography. Treatment with a fluoroquinolone should be continued for 6 weeks. Cyst aspiration is necessary only when cysts are very large and/or when infection is resistant to antibiotic treatment. In patients who are candidates to kidney transplantation, a history of recurrent kidney cyst infection justifies pre-transplant nephrectomy, while a past history of recurrent liver cyst infection or angiocholitis leads to consider liver transplantation. Among extrarenal and extrahepatic complications of polycystic disease, colic diverticulosis is reported to be associated with increased risk of infection in patients on hemodialysis and after kidney transplantation. However, this observation needs to be confirmed.

Systematic review: the management of hepatic cyst infection

BACKGROUND

Cyst infection is a severe complication of hepatic cystic disease. However, an evidence-based treatment strategy is not available.

AIM

To assess the available treatment strategies and provide a treatment advice for de novo hepatic cyst infection.

METHODS

We systematically searched PubMed (1948-2014), EMBASE (1974-2014), and the Cochrane Library (until 2014) for studies involving humans (≥18 years) treated for a hepatic cyst infection. We extracted data on patient characteristics, treatment and follow-up.

RESULTS

We identified 41 articles; all were case series or case reports, implicating a high risk of bias. We included 54 hepatic cyst infection cases (male 39%; mean age 63 ± 12 years; diabetes 6%; dialysis 19%; transplant recipients 30%). Initial therapy consisted of antimicrobial (56%), percutaneous (31%) or surgical treatment (13%). We identified 42 antimicrobial regimens consisting of 23 different combinations. Most used antibiotic classes were quinolones (34%) and cephalosporins (34%). Antimicrobials failed in 70% of cases, eventually requiring percutaneous or surgical treatment in, respectively, 37% and 27%. Recurrent hepatic cyst infection was frequent (20%). Median time to recurrence was 8 weeks (IQR 3-24 weeks). In 46%, recurrence occurred in renal transplant recipients. Cyst infection related deaths occurred in 9%, of whom 40% were on dialysis.

CONCLUSIONS

The literature shows that treatment of hepatic cyst infection is highly heterogeneous. We recommend first line treatment with oral ciprofloxacin. In case of failure, percutaneous cyst drainage needs to be considered.

Diagnosis and management of polycystic liver disease

Polycystic liver disease (PLD) is arbitrarily defined as a liver that contains >20 cysts. The condition is associated with two genetically distinct diseases: as a primary phenotype in isolated polycystic liver disease (PCLD) and as an extrarenal manifestation in autosomal dominant polycystic kidney disease (ADPKD). Processes involved in hepatic cystogenesis include ductal plate malformation with concomitant abnormal fluid secretion, altered cell-matrix interaction and cholangiocyte hyperproliferation. PLD is usually a benign disease, but can cause debilitating abdominal symptoms in some patients. The main risk factors for growth of liver cysts are female sex, exogenous oestrogen use and multiple pregnancies. Ultrasonography is very useful for achieving a correct diagnosis of a polycystic liver and to differentiate between ADPKD and PCLD. Current radiological and surgical therapies for symptomatic patients include aspiration-sclerotherapy, fenestration, segmental hepatic resection and liver transplantation. Medical therapies that interact with regulatory mechanisms controlling expansion and growth of liver cysts are under investigation. Somatostatin analogues are promising; several clinical trials have shown that these drugs can reduce the volume of polycystic livers. The purpose of this Review is to provide an update on the diagnosis and management of PLD with a focus on literature published in the past 4 years.