Intracranial aneurysms in autosomal dominant polycystic kidney disease

Autosomal Dominant Polycystic Kidney Disease: Extrarenal Involvement

Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary kidney disorder, but kidneys are not the only organs involved in this systemic disorder. Individuals with the condition may display additional manifestations beyond the renal system, involving the liver, pancreas, and brain in the context of cystic manifestations, while involving the vascular system, gastrointestinal tract, bones, and cardiac valves in the context of non-cystic manifestations. Despite kidney involvement remaining the main feature of the disease, thanks to longer survival, early diagnosis, and better management of kidney-related problems, a new wave of complications must be faced by clinicians who treated patients with ADPKD. Involvement of the liver represents the most prevalent extrarenal manifestation and has growing importance in the symptom burden and quality of life. Vascular abnormalities are a key factor for patients' life expectancy and there is still debate whether to screen or not to screen all patients. Arterial hypertension is often the earliest onset symptom among ADPKD patients, leading to frequent cardiovascular complications. Although cardiac valvular abnormalities are a frequent complication, they rarely lead to relevant problems in the clinical history of polycystic patients. One of the newest relevant aspects concerns bone disorders that can exert a considerable influence on the clinical course of these patients. This review aims to provide the "state of the art" among the extrarenal manifestation of ADPKD.

Impact of kidney function and kidney volume on intracranial aneurysms in patients with autosomal dominant polycystic kidney disease

Presently, only personal or family history of intracranial aneurysm/subarachnoid hemorrhage (IA/SAH) has been established as a risk factor for IA in autosomal dominant polycystic kidney disease (ADPKD). This study aimed to verify the association between kidney function/volume and IAs in patients with ADPKD. This study included 519 patients with ADPKD. At baseline IA screening, the median age and estimated glomerular filtration rate were 44 years and 54.5 mL/min/1.73 m², respectively. Family IA/SAH history was confirmed in 18.1% of the patients, and 54.3% of the patients had hypertension. The IA point prevalence was 12.5%. During clinical follow up of 3104 patient-years, de novo IA was detected in 29 patients (0.93% patient-years). The IA period prevalence was 18.1% (median age, 60 years). Multivariable logistic regression demonstrated that total kidney volume (TKV) ≥ 1000 mL (odds ratio [OR] = 2.81), height-adjusted TKV ≥ 500 mL (OR = 2.81), Mayo imaging classification Class 1D-1E (OR = 2.52), and chronic kidney disease stages 3-5 (OR = 2.31) were significantly associated with IA formation. IAs in patients with ADPKD may be associated not only with general risk factors for IAs but also with declining kidney function and increased KV. Kidney disease progression may contribute to effective IA screening and treatment planning in patients with ADPKD.

MR Brain Screening in ADPKD Patients : To Screen or not to Screen?

BACKGROUND

Adult polycystic kidney disease (ADPKD) still represents a major cause of renal failure and intracranial aneurisms (IA) have a higher prevalence in ADPKD than in the general population. Current guidelines suggest performing brain MRI only in the subjects with a positive familiar history of IAs or subarachnoid hemorrhage (SAH). This is a retrospective case-control analysis to evaluate the usefulness of a MR screening program in ADPKD patients.

METHODS

We retrospectively analyzed all ADPKD patients followed in our outpatient clinic between 2016 and 2019 who underwent a brain MRI screening. We evaluated the presence of IAs and others brain abnormalities and compared our results with a non-ADPKD population (n = 300). We performed univariate and multivariate regression analysis to evaluate if general and demographic features, laboratory findings, clinical parameters and genetic test results correlated with IAs or other brain abnormalities presence.

RESULTS

Among the patients evaluated 17 out of 156 (13.6%) ADPKD patients had IAs, compared to 16 out of 300 (5.3%) non-ADPKD controls (p < 0.005). Considering ADPKD patients presenting IAs, 12 (70.6%) had no family history for IAs or SAH. Genetic analysis was available for 97 patients: in the sub-population with IAs, 13 (76.5%) presented a PKD1 mutation and none a PKD2 mutation. We found that arachnoid cysts (AC) (p < 0.001) and arterial anatomical variants (p < 0.04) were significantly more frequent in ADPKD patients.

CONCLUSION

In our population ADPKD patients showed a higher prevalence of IAs, AC and arterial variants compared to non-ADPKD. Most of the IAs were found in patients presenting a PKD1 mutation. We found a significant number of alterations even in those patients without a family history of IAs or SAH. The practice of submitting only patients with familial IAs or kidney transplantation candidates to MRI scan should be re-evaluated.

PKD1-Associated Arachnoid Cysts in Autosomal Dominant Polycystic Kidney Disease

OBJECTIVES

the prevalence of intracranial aneurysms and arachnoid cysts is higher in patients with autosomal dominant polycystic kidney disease (ADPKD) than in the general population. A genotype correlation was reported for intracranial aneurysms, but it is unclear for arachnoid cysts. Therefore, the genotype correlation with intracranial aneurysms and arachnoid cysts was investigated in ADPKD.

MATERIALS AND METHODS

intracranial aneurysms and arachnoid cysts were screened by magnetic resonance imaging (MRI), and PKD genotypes were examined using next-generation sequencing for 169 patients with ADPKD.

RESULTS

PKD1-, PKD2- and no-mutation were identified in 137, 24 and 8 patients, respectively. Intracranial aneurysms and arachnoid cysts were found in 34 and 25 patients, respectively, with no significant difference in frequency. Genotype, sex, estimated glomerular filtration rate and age at ADPKD diagnosis significantly affected the age at brain MRI. The proportional hazard risk analyzed using the age at brain MRI adjusted by these four variables was 5.0-times higher in the PKD1 group than in the PKD2 group for arachnoid cysts (P = 0.0357), but it was not different for intracranial aneurysms (P = 0.1605). Arachnoid cysts were diagnosed earlier in the PKD1 group than in the PKD2 group (54.8 vs 67.7 years, P = 0.0231), but no difference was found for intracranial aneurysms (P = 0.4738) by Kaplan-Meier analysis.

CONCLUSIONS

this study demonstrated the correlation between arachnoid cysts and PKD1 mutation. The reported association of arachnoid cysts with advanced renal disease may be due to the common correlation of these factors with PKD1 mutation.

Imaging for Treated Aneurysms (Including Clipping, Coiling, Stents, Flow Diverters)

Intracranial aneurysms are common in the adult population and carry a risk of rupture leading to catastrophic subarachnoid hemorrhage. Treatment of aneurysms has evolved significantly, with the introduction of new techniques and devices for minimally invasive and endovascular approaches. Follow-up imaging after aneurysm treatment is standard of care to monitor for recurrence or other complications, and the preferred imaging modality and schedule for follow-up are areas of active research. The modality and follow-up schedule should be tailored to treatment technique, aneurysm characteristics, and patient factors.

Aneurysm morphology in patients with autosomal dominant polycystic kidney disease: A case-control study

PURPOSE

Approximately 8% of patients with autosomal dominant polycystic kidney disease (ADPKD) develop intracranial aneurysms. The reason for development of intracranial aneurysms in ADPKD patients might be related to interactions between the presence of hypertension and the basic mechanism underlying the disease, which leads to weakness of the connective tissue. In this study, we aimed to identify differences in aneurysm morphology between ADPKD patients and a location-matched set of controls.

METHODS

A total of 42 ADPKD patients and 49 control patients with 122 aneurysms were included. Aneurysm size, location, and morphology were evaluated by two neuroradiologists. Aneurysm morphology was classified into one of three groups: regular saccular, irregular saccular, and fusiform. Continuous variables were compared with chi-squared tests and categorical variables were compared with student's t-test.

RESULTS

When considering all patients, there was no significant difference in aneurysm morphology or size (4.5 ± 2.6 mm vs 5.4 ± 2.9 mm; p = 0.09) between the ADPKD and control group. In a subgroup analysis of medium and large aneurysms (n = 61), there was a significantly lower incidence of regular saccular aneurysms (28% vs. 56%; p = 0.03) and higher incidence of fusiform aneurysms (12% vs 0%; p = 0.03) in the ADPKD group compared to a control group.

CONCLUSION

When excluding categorically "small" aneurysms, there is a reduced incidence of regular saccular aneurysms and increased incidence of fusiform aneurysms in ADPKD patients compared to a control group. Further study of this population of patients is warranted to better understand their risks of aneurysm rupture and indications for treatment.

Subarachnoid Hemorrhage in Hospitalized Renal Transplant Recipients with Autosomal Dominant Polycystic Kidney Disease: A Nationwide Analysis

Background: This study aimed to evaluate the hospitalization rates for subarachnoid hemorrhage (SAH) among renal transplant patients with adult polycystic kidney disease (ADPKD) and its outcomes, when compared to non-ADPKD renal transplant patients. Methods: The 2005–2014 National Inpatient Sample databases were used to identify all hospitalized renal transplant patients. The inpatient prevalence of SAH as a discharge diagnosis between ADPKD and non-ADPKD renal transplant patients was compared. Among SAH patients, the in-hospital mortality, use of aneurysm clipping, hospital length of stay, total hospitalization cost and charges between ADPKD and non-ADPKD patients were compared, adjusting for potential confounders. Results: The inpatient prevalence of SAH in ADPKD was 3.8/1000 admissions, compared to 0.9/1000 admissions in non-ADPKD patients (p < 0.01). Of 833 renal transplant patients with a diagnosis of SAH, 30 had ADPKD. Five (17%) ADPKD renal patients with SAH died in hospitals compared to 188 (23.4%) non-ADPKD renal patients (p = 0.70). In adjusted analysis, there was no statistically significant difference in mortality, use of aneurysm clipping, hospital length of stay, or total hospitalization costs and charges between ADPKD and non-ADPKD patients with SAH. Conclusion: Renal transplant patients with ADPKD had a 4-fold higher inpatient prevalence of SAH than those without ADPKD. Further studies are needed to compare the incidence of overall admissions in ADPKD and non-ADPKD patients. When renal transplant patients developed SAH, inpatient mortality rates were high regardless of ADPKD status. The outcomes, as well as resource utilization, were comparable between the two groups.

Polycystic kidney disease among 4,436 intracranial aneurysm patients from a defined population

OBJECTIVE

To define the association of autosomal dominant polycystic kidney disease (ADPKD) with the characteristics of aneurysmal subarachnoid hemorrhage (aSAH) and unruptured intracranial aneurysm (IA) disease.

METHODS

We fused data from the Kuopio Intracranial Aneurysm database (n = 4,436 IA patients) and Finnish nationwide registries into a population-based series of 53 IA patients with ADPKD to compare the aneurysm- and patient-specific characteristics of IA disease in ADPKD and in the general IA population, and to identify risks for de novo IA formation.

RESULTS

In total, there were 33 patients with ADPKD with aSAH and 20 patients with ADPKD with unruptured IAs. The median size of ruptured IAs in ADPKD was significantly smaller than in the general population (6.00 vs 8.00 mm) and the proportion of small ruptured IAs was significantly higher (31% vs 18%). Median age at aSAH was 42.8 years, 10 years younger than in the general IA population. Multiple IAs were present in 45% of patients with ADPKD compared to 28% in the general IA population. Cumulative risk of de novo IA formation was 1.3% per patient-year (vs 0.2% in the general IA population). Hazard for de novo aneurysm formation was significantly elevated in patients with ADPKD (Cox regression hazard ratio 7.7, 95% confidence interval 2.8-20; p < 0.0005).

CONCLUSIONS

Subarachnoid hemorrhage occurs at younger age and from smaller IAs in patients with ADPKD and risk for de novo IAs is higher than in the general Eastern Finnish population. ADPKD should be considered as an indicator for long-term angiographic follow-up in patients with diagnosed IAs.

Natural history of intracranial aneurysms in autosomal dominant polycystic kidney disease

Autosomal-dominant polycystic kidney disease (ADPKD) is a relatively frequent genetic disorder that is associated with increased prevalence of intracranial aneurysms (IAs). However, evidence on the natural history of IAs in ADPKD is suboptimal. That leads to difficulties in development of recommendations on surveillance on patients with IAs in their medical history, or the need for repeat imaging for IAs in those with a negative result of the initial screening. The aim of the article is to present our experience on the natural history of IAs in ADPKD patients.

MATERIAL AND METHODS

Thirty-four ADPKD patients, managed at our outpatient department, with imaging for intracranial aneurysms performed at least twice, were included into present retrospective analysis.

RESULTS

Among 8 patients with an IA in their medical history, no new IA was observed during 93 patient-years of follow-up. In 6 patients with untreated, unruptured IAs, IA growth was observed in 2 cases during 32 patient-years of follow-up. Finally, among 20 patients with a negative result of initial screening, 2 new IAs were noticed during 115 patient-years of follow-up, including 1 patient with a positive family history for an IA, and 1 patient without a family history.

CONCLUSIONS

Our observations support repeat imaging for IAs in patients with ADPKD, positive family history of IA, and negative result of initial screening. Additionally, efforts should be made to develop clinical and/or laboratory risk factors for IAs development in ADPKD patients without family history of IA, which enable to identify patients who should undergo repeat imaging for IAs.

Is Regular Screening for Intracranial Aneurysm Necessary in Patients with Autosomal Dominant Polycystic Kidney Disease? A Systematic Review and Meta-analysis

BACKGROUND

The prevalence of intracranial aneurysm in patients with autosomal dominant polycystic kidney disease (ADPKD) is higher than that among the general population. We performed a systematic review and meta-analysis on the prevalence and natural history of intracranial aneurysm among patients with ADPKD.

METHODS

Medline, Embase, Web of Science and Scopus, from inception to July 2016, were searched for studies reporting the occurrence of intracranial aneurysms among participants with ADPKD. Two authors independently assessed the eligibility of all retrieved studies and extracted data. Information on the prevalence of intracranial aneurysms and their natural history in participants with ADPKD was collected from all included studies.

RESULTS

Fifteen studies with 1,490 participants with ADPKD were pooled to study about the prevalence of intracranial aneurysm in participants with ADPKD, and the prevalence rate was found to be 10% (95% CI 7-13%). Studies from China, Japan and Europe (Germany, Poland) reported a higher prevalence of intracranial aneurysm. Having a family history of haemorrhagic stroke or intracranial aneurysm was a risk factor for aneurysm occurrence. Twenty-three percent (95% CI 15-31%) of the participants had multiple aneurysms. Most of the aneurysms were small (<6 mm) and located in the anterior circulation. Five studies with 171 participants (83 with 106 aneurysms at baseline and 88 without) were analyzed to understand the natural history of aneurysms, with an incidence of aneurysm growth, new aneurysm and aneurysm rupture of 1.84% (followed up for 435 person-years), 0.57% (1,227 person-years) and 0.13% (792 person-years) respectively.

CONCLUSIONS

Screening for intracranial aneurysm is recommended in patients with ADPKD when there is a family history of haemorrhagic stroke or intracranial aneurysm and when they are from China, Japan or Europe (Germany, Poland). Based on existing data, regular imaging follow-up is not supported. High-quality, prospective studies are needed in the future.

Intracranial aneurysms in patients with autosomal dominant polycystic kidney disease: prevalence, risk of rupture, and management. A systematic review

BACKGROUND

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disorder associated with high incidences of intracranial aneurysms. We performed a systematic review with the purpose of clarifying the prevalence, risk of rupture, and appropriate management of intracranial aneurysms in the ADPKD population.

METHOD

PRISMA guidelines were followed. We conducted a comprehensive literature search of three databases (PubMed, Ovid MEDLINE, and Ovid EMBASE) on all series reporting ADPKD patients with intracranial aneurysms.

RESULTS

Our systematic review included 16 articles with a total of 563 patients with ADPKD and intracranial aneurysms. The prevalence of unruptured aneurysms was 11.5% (95% CI = 10.1-13%), whereas 1.9% (95% CI = 1.3-2.6%) of aneurysms were ruptured. Hypertension was present in 79.3% of patients with ADPKD and renal impairment in 65%. The mean size of ruptured aneurysms was slightly higher than unruptured (6 mm vs. 4.4 mm). The most common locations of unruptured and ruptured aneurysms were the ICA (40.5%) and MCA (45%), respectively. Asymptomatic patients studied with four-vessel angiography experienced 25% transient complications. Overall, 74% unruptured aneurysms were surgically treated with lower complication rates compared to endovascular treatment (11% vs. 27.7%). Among conservatively treated aneurysms, 2.9% ruptured at follow-up (rupture rate 0.4%/patient-year). Finally, the growth rate was 0.4% per patient-year, and the incidence of de novo aneurysm formation was 1.4% per patient-year.

CONCLUSIONS

The prevalence of unruptured intracranial aneurysms in the ADPKD population is approximately 11%. Given the non-negligible rate of procedural complications, the management of these patients must be cautious and individualised. The rupture rate appears comparable to that of the general population. On the other hand, the 1.4% rate per patient-year of de novo aneurysms is non-negligible. These findings should be considered when counselling ADPKD patients regarding the appropriate management of intracranial aneurysms.

A Review of the Genetics of Intracranial Berry Aneurysms and Implications for Genetic Counseling

Here we review the current understanding of the genetic architecture of intracranial berry aneurysms (IBA) to aid in the genetic counseling of patients at risk for this condition. The familial subtype of IBA, familial intracranial aneurysms (FIA), is associated with increased frequency of IBA, increased risk of rupture, and increased morbidity and mortality after rupture. Family history is the strongest predictor for the development of IBA. However, a genetic test is not yet available to assess risk within a family. Studies using linkage analysis, genome-wide association, and next-generation sequencing have found several candidate loci and genes associated with disease onset, but have not conclusively implicated a single gene. In addition to family history, a separate or concurrent diagnosis of autosomal dominant polycystic kidney disease is a strong genetic risk factor for IBA formation. We also discuss the relative risk for developing IBA in several Mendelian syndromes including vascular Ehlers-Danlos syndrome, Marfan syndrome, Neurofibromatosis Type I, and Loeys-Dietz syndrome.

Diagnostic Imaging of Autosomal Dominant Polycystic Kidney Disease

Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common genetic disorders caused by a single gene mutation. The disease usually manifests itself at the age of 30-40 years and is characterized by formation of renal cysts along with the enlargement of kidneys and deterioration of their function, eventually leading to renal insufficiency. Imaging studies (sonography, computed tomography, magnetic resonance imaging) play an important role in the diagnostics of the disease, the monitoring of its progression, and the detection of complications. Imaging is also helpful in detecting extrarenal manifestations of ADPKD, most significant of which include intracranial aneurysms and cystic liver diseases.

Headache as a manifestation of intracranial aneurysm in autosomal dominant polycystic kidney disease

BACKGROUND

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disorder that affects 1 in 1.000 people in the general population, and is connected to increased risk for intracranial aneurysms (ICANs). In this work, we made an attempt to identify risk factors for subarachnoid hemorrhage (SAH) due to a rupture of an ICAN.

METHODS

Retrospective analysis of series of cases including 8 ADPKD patients who passed a nonfatal stroke due to the rupture of an ICAN.

RESULTS

The mean age at SAH was 40.13 years. In 88% of patients the renal function at SAH was normal. At least 63% of patients were hypertensive. The family history for ICAN and/or SAH was positive in 38% of patients, and in 63% of patients there were neurological symptoms preceding SAH, with headache as the most common one.

CONCLUSIONS

Similarly to ICAN and/or SAH in the family history, headache and/or other neurological symptoms should be indication for screening for ICANs in all ADPKD patients irrespectively of their age. We propose a set of criteria, which may enable detection of most cases of ICANs in ADPKD patients.