The spectacular fossil plant assemblage preserved in the non-marine Mount Flora Formation of the northern Antarctic Peninsula represents the diverse Jurassic flora that once covered the Gondwanan ...continents at high paleolatitudes. The depositional facies of the formation plays a key role in the tectonic interpretations and basin evolution models that attempt to reconcile large igneous province magmatism, continental break up, and magmatic arc development throughout the Jurassic and Cretaceous. Limited U–Pb in situ geochronology reported from the Mount Flora Formation and adjacent units lack the necessary resolution to overcome ambiguous correlations and biostratigraphic discrepancies. We present two high-precision U–Pb zircon ages (CA-ID-TIMS method) from a distinct tuffaceous interval of the Mount Flora Formation at Hope Bay, which document a terminal Middle Jurassic age (Callovian Stage) for the formation and its paleoflora. In excess of 1400 new collected fossil plant specimens exhibit a highly diverse Jurassic plant association that dominated the Antarctic Peninsula nearly 17 million years after its disappearance from northern Patagonia. This suggests similar paleoecological conditions were established diachronously throughout basins of southern Gondwana, possibly facilitating floral migrations in response to local climate change. The depositional facies of the Mount Flora Formation, its age proximity to the marine Nordenskjöld Formation in the Antarctic Larsen Basin and its coincidence with a regional unconformity in the northern Patagonia point out to a complex interplay among magmatic arc development, tectonic extension and continental break up that dominated the geologic and paleoenvironmental evolution of southern Gondwana near the end of the Middle Jurassic.
Pretransplant donor biopsy (PTDB)‐based marginal donor allocation systems to single or dual renal transplantation could increase the use of organs with Kidney Donor Profile Index (KDPI) in the ...highest range (e.g. >80 or >90), whose discard rate approximates 50% in the United States. To test this hypothesis, we retrospectively calculated the KDPI and analyzed the outcomes of 442 marginal kidney transplants (340 single transplants: 278 with a PTDB Remuzzi score <4 median KDPI: 87; interquartile range (IQR): 78–94 and 62 with a score = 4 median KDPI: 87; IQR: 76–93; 102 dual transplants median KDPI: 93; IQR: 86–96) and 248 single standard transplant controls (median KDPI: 36; IQR: 18–51). PTDB‐based allocation of marginal grafts led to a limited discard rate of 15% for kidneys with KDPI of 80–90 and of 37% for kidneys with a KDPI of 91–100. Although 1‐year estimated GFRs were significantly lower in recipients of marginal kidneys (−9.3, −17.9 and −18.8 mL/min, for dual transplants, single kidneys with PTDB score <4 and =4, respectively; p < 0.001), graft survival (median follow‐up 3.3 years) was similar between marginal and standard kidney transplants (hazard ratio: 1.20 95% confidence interval: 0.80–1.79; p = 0.38). In conclusion, PTDB‐based allocation allows the safe transplantation of kidneys with KDPI in the highest range that may otherwise be discarded.
This study shows that the standardized assessment of formalin‐fixed pretransplant biopsies helps recover donors with KDPI in the highest range that would be otherwise discarded, and by providing the expected graft outcomes based on KDPI and pretransplant biopsy, it guides the clinician facing the difficult decision whether to accept or reject these organs. See editorial by Gupta et al on page 2444.
Background
Medullary sponge kidney is generally considered a benign condition, gold standard for the diagnosis is urography but it has almost been replaced by UroCT that did not present the same ...sensibility. Although it is really rare, our sonography’s findings were consistent with medullary sponge kidney in the transplanted kidneys.
Case presentation
A 45-year-old woman with a long history of double-kidney transplantation complained of frequent urinary tract infections, a history of vague loin pain and came to our attention for sonography follow-up. Her kidney function was normal, we did not find signs of infections in the transplanted kidneys and urinary findings were normal. Curiously, the transplanted kidneys came from a newborn and the patient received a double-kidney transplantation in order to guarantee a satisfactory renal function.
Conclusions
Despite a long history of kidney transplantation, genetic disease should not be forgotten when symptoms and images recall to specific inherited alterations. Sonography has to be considered in diagnostic path of kidney cystic disease.
MR Brain Screening in ADPKD Patients Capelli, I.; Zoli, M.; Righini, M. ...
Clinical neuroradiology (Munich),
03/2022, Letnik:
32, Številka:
1
Journal Article
Recenzirano
Odprti dostop
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.
Although optimization of immunosuppressive schemes in renal transplantation have minimized acute posttransplant complications, long-term outcomes are still not optimal and most of the chronic graft ...damage is drug-related. Therefore, to define the best long-term maintenance immunosuppressive regimen is of major importance in renal transplantation. To assess this objective, we undertook a large, multicenter cohort study in Italy.
We retrospectively analyzed data of 5635 patients (enrolled from 1983 to 2012) and we assessed the impact of 3 major immunosuppressive regimens (calcineurin inhibitors+antimetabolites+corticosteroids CNI+ANT+CS vs CNI+mammalian target-of-rapamycin (mTOR) inhibitors+CS CNI+mTOR-I+CS vs CNI+CS) on long-term clinical outcomes by employing several statistical algorithms.
The overall difference in the incidence of outcome over time was not statistically different within the first 5 years of follow-up (P = .13); however, it became significant at 10 years and 20 years (P < .01), with the CNI+CS group showing the lowest cumulative incidence of outcome. Compared with the CNI+ANT+CS group, the CNI+mTOR-I+CS group patients had a significantly higher risk of outcome (hazard ratio HR, 1.30; P = .024); the difference remained significant and even increased in magnitude after adjustment for potential confounders (HR, 1.38; P = .006). Similarly, patients in the CNI+CS group had a significantly higher risk of the outcome (HR, 1.64; P < .001).
Our data confirm that CNI+ANT+CS is the “gold standard” therapy in renal transplantation, but, whenever required, the introduction of mTOR-Is instead of ANT may not dramatically modify major clinical outcomes. The use of mTOR-I could be a valuable pharmacologic tool to minimize CNI complications and insure adequate immunosuppression.
•Calcineurin inhibitor+antimetabolite+steroid is still the “gold standard” in immunosuppressive therapy.•Mammalian target-of-rapamycin inhibitors (mTOR-Is), instead of antimetabolites, do not modify major long-term clinical outcomes.•mTOR-I+CNI represents a valuable immunosuppressive strategy in transplantation.
Introduction:
Renal allograft biopsy is the gold standard for the detection of histological lesions of chronic allograft dysfunction. The identification of a noninvasive routine test would be ...desirable. Elastosonography is used to assess tissue stiffness according to viscosity, and no data are available on the use of point quantification shear-wave elastography (ElastPQ) for the evaluation of renal chronic lesions.
Research Question:
To evaluate the feasibility of ElastPQ to assess cortical allograft stiffness and to determine the correlation of clinical, biological, and pathological factors with the diagnostic accuracy of kidney stiffness values in patients with histological lesions.
Design:
Forty-two patients underwent kidney transplant biopsy and 10 valid measurements of ElastPQ, blindly performed by 2 operators. The interobserver reproducibility was assessed according to intraclass correlation coefficient. The ElastPQ measurements and the clinical data were compared using the Spearman correlation analysis.
Results:
97.6% reliable measurements were obtained using ElastPQ, with an excellent interobserver agreement. The kidney stiffness was significantly higher in the patients with a time since transplantation >12 months and was correlated with chronic lesions (interstitial fibrosis, tubular atrophy transplant glomerulopathy, and mesangial matrix), with the interstitial fibrosis/tubular atrophy, score and with the sum of the scores of the chronic lesions. Mesangial matrix increase is the only independent determinant of kidney stiffness.
Discussion:
ElastPQ is a noninvasive, reproducible, and sensitive diagnostic tool able to detect moderate/severe chronic lesions. Its routine use during follow-up can identify patients eligible for biopsy, which remains the gold standard exam for detecting chronic allograft dysfunction.
Electrocardiogram (ECG) has proven to be useful for early detection of cardiac involvement in Anderson-Fabry disease (AFD); however, little evidence is available on the association between ECG ...alterations and the progression of the disease.
To perform a cross sectional comparison of ECG abnormalities throughout different left ventricular hypertrophy (LVH) severity subgroups, providing ECG patterns specific of the progressive AFD stages. 189 AFD patients from a multicenter cohort underwent comprehensive ECG analysis, echocardiography, and clinical evaluation.
The study cohort (39% males, median age 47 years, 68% classical AFD) was divided into 4 groups according to different degree of left ventricular (LV) thickness: group A ≤ 9 mm (
= 52, 28%); group B 10-14 mm (
= 76, 40%); group C 15-19 mm (
= 46, 24%); group D ≥ 20 mm (
= 15, 8%). The most frequent conduction delay was right bundle branch block (RBBB), incomplete in groups B and C (20%,22%) and complete RBBB in group D (54%,
< 0.001); none of the patients had left bundle branch block (LBBB). Left anterior fascicular block, LVH criteria, negative T waves, ST depression were more common in the advanced stages of the disease (
< 0.001). Summarizing our results, we suggested ECG patterns representative of the different AFD stages as assessed by the increases in LV thickness over time (Central Figure). Patients from group A showed mostly a normal ECG (77%) or minor anomalies like LVH criteria (8%) and delta wave/slurred QR onset + borderline PR (8%). Differently, patients from groups B and C exhibited more heterogeneous ECG patterns: LVH (17%; 7% respectively); LVH + LV strain (9%; 17%); incomplete RBBB + repolarization abnormalities (8%; 9%), more frequently associated with LVH criteria in group C than B (8%; 15%). Finally, patients from group D showed very peculiar ECG patterns, represented by complete RBBB + LVH and repolarization abnormalities (40%), sometimes associated with QRS fragmentation (13%).
ECG is a sensitive tool for early identification and long-term monitoring of cardiac involvement in patients with AFD, providing "instantaneous pictures" along the natural history of AFD. Whether ECG changes may be associated with clinical events remains to be determined.
Abstract Introduction It is widely accepted that the risk of malignancies is significantly increased among patients with end-stage kidney disease (ESKD) and after kidney transplantation compared with ...the general population. Only a few data are available on kidney transplantation waiting list patients. The aim of this study was to investigate solid organ cancer incidence among subjects on the waiting list at a single center. Materials and Methods We retrospectively reviewed the records of all patients enrolled on our kidney transplantation waiting list between August 1, 2008 and July 31, 2010, seeking to evaluate the causes of withdrawal from the list, incidence of cancer, type of neoplasm, and its correlation with clinical features. We estimated the ratio of observed to expected numbers of cancers, the standardized incidence ratio (SIR). Results Among 1184 patients, we excluded 569 patients from the waiting list including 26 (4.56%) who displayed malignancies. The overall incidence of cancer was 0.11 events/person-months and the overall prevalence of cancer was 2.2%. In 97% of patients, the malignant disease was confined to the primitive organ of origin without secondary dissemination. We observed a prevalence of cancers related to ESKD (17; 65.38%). The SIR for all cancer types in our population compared with the general population was 2.22. The SIR for native kidney and thyroid cancers among our population compared with the general population was >10. Conclusion The incidence of cancer was significantly increased among kidney transplantation waiting list patients compared with the general population. Our study highlighted the importance of a careful, targeted neoplastic screening. It could be particularly important for ESKD-related malignancies like native kidney tumors or thyroid cancers.
Paget's disease is the second most common bone disease after osteoporosis and causes an excessive bone turnover. Moreover, chronic kidney failure causes an impairment of bone mineral metabolism and ...electrolytes and PTH homeostasis. As far as we know, this is the first reported case of Paget's disease in a hemodialysis patient: the patient was also affected by secondary hyperparathyroidism and was successfully treated with clodronate, cinacalcet and paracalcitol. The safety and efficacy of this combined therapy was periodically revised in a 12-month follow-up considering the common markers of bone turnover as well as the dosage of OPG, RANKL, IL-6 and MCSF, involved in the pathophysiology of Paget's disease.
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