Hepatopulmonary syndrome with large pulmonary arteriovenous malformations: CT findings with emphasis on its association with a mosaic pattern of the lung parenchyma.

We present a case of a 54-year-old patient with cirrhosis, progressive dyspnea, and platypnea. Thoracic computed tomography (CT) showed multiple pulmonary arteriovenous malformations (PAVM), confirming the diagnosis of hepatopulmonary syndrome (HPS). Besides precisely identifying the number and location of PAVM, CT also demonstrated a striking mosaic pattern of the lung parenchyma, characterized by the presence of alternating geographic areas of low attenuation (showing pulmonary vessels with a decreased diameter) with regions of relatively increased attenuation (showing pulmonary vessels with a normal diameter). This mosaic pattern of the lung parenchyma has scarcely been described in patients with HPS since it is not always present and usually requires a post-processing of the CT images in order to increase the contrast between the low attenuation areas (representing hypoperfused regions) and the areas with a relatively increased attenuation (representing better perfused regions). The decision was made to embolize the major PAVM, achieving an improvement of both the oxygen partial pressure and the patient's symptoms. This improvement allowed the patient to become an acceptable candidate for liver transplantation. We believe that, unlike other radiological signs of HPS, the mosaic pattern has not been sufficiently described in the scientific literature. If the association of the mosaic pattern on CT with HPS is confirmed in larger studies, it could become a useful sign for detecting hypoperfused pulmonary areas related to small nonvisible PAVM.

Oral Sodium Chloride in the Prevention of Contrast-Associated Acute Kidney Injury in Elderly Outpatients: The PNIC-Na Randomized Non-Inferiority Trial.

OBJECTIVE: We aimed to test the non-inferiority of oral versus intravenous hydration in the incidence of contrast-associated acute kidney injury (CA-AKI) in elderly outpatients undergoing a contrast-enhanced computed tomography (CE-CT) scan. METHODS: PNIC-Na (NCT03476460) is a phase-2, single-center, randomized, open-label, non-inferiority trial. We included outpatients undergoing a CE-CT scan, >65 years having at least one risk factor for CA-AKI, such as diabetes, heart failure, or an estimated glomerular filtration rate (eGFR) of 30-59 mL/min/1.73 m². Participants were randomized (1:1) to oral sodium-chloride capsules or intravenous hydration. The primary outcome was an increase in serum creatinine >0.3 mg/dL or a reduction in eGFR >25% within 48 h. The non-inferiority margin was set at 5%. RESULTS: A total of 271 subjects (mean age 74 years, 66% male) were randomized, and 252 were considered for the main analysis (per-protocol). A total of 123 received oral hydration and 129 intravenous. CA-AKI occurred in 9 (3.6%) of 252 patients and 5/123 (4.1%) in the oral-hydration group vs. 4/129 (3.1%) in the intravenous-hydration group. The absolute difference between the groups was 1.0% (95% CI -4.8% to 7.0%), and the upper limit of the 95% CI exceeded the pre-established non-inferiority margin. No major safety concerns were observed. CONCLUSION: The incidence of CA-AKI was lower than expected. Although both regimens showed similar incidences of CA-AKI, the non-inferiority was not shown.

Prospective long-term experience in the treatment of renal tumors with cryotherapy: follow-up with computed tomography scan and contrast-enhanced ultrasound.

Introduction: The aim of this article was to evaluate the oncological results and safety of cryotherapy for the treatment of renal tumors. Material and methods: This study was a prospective review and follow-up of patients who underwent cryotherapy from January 2008 to May 2021. Cryotherapy was offered to patients with bilateral tumors, tumors in solitary kidneys, or comorbid patients. Follow-up consisted of a computed tomography (CT) scan and contrast-enhanced ultrasound (CEUS), with analysis of concordance (kappa index). Overall survival and kidney survival were analyzed (Kaplan-Meier). Results: Cryotherapy was performed 71 times in 67 patients. A total of 74.6% of patients were men. The mean age of patients was 69.7 years (standard deviation (SD) 11.3]. Mean follow-up was 52.7 months (SD 36.2). Mean tumor size was 26.2 mm (SD 7.6). 90% were cT1a, 10% cT1b stage. Type of access was open in 1 patient, laparoscopic in 8, percutaneous US-guided in 8 and percutaneous CT-guided in 54 patients. Biopsy was taken in 60 patients (84.5%) and consisted of renal cell carcinoma (22), oncocytoma (9), papillary carcinoma (4), angiomyolipoma (1), sarcoma (1), and non-conclusive (23).There were 22 complications such as pain in 2 patients, hematoma in 8 and 2 cases of bleeding, all resolved conservatively except for one case of bleeding which required embolization.Recurrences occurred in 16 cases (22.5%). Management was cryotherapy in 25%, radical nephrectomy in 31.3% and surveillance in 43.8%. Concordance between contrast-enhanced ultrasound and CT was 0.8 (excellent).Mean glomerular filtration did not change. One patient developed metastasis.No cancer-specific mortality was found. Overall survival at 12, 24 and 48 months was 98.5%, 96.8% and 76.9% respectively. Kidney survival at 12, 24 and 48 months was 97%, 93.5% and 93.5% respectively. Conclusions: Cryotherapy for renal tumors is a safe treatment for comorbid or solitary kidney patients, with rare major complications and good oncological outcome.

[Renal allograft transplant vascular complications. Diagnostic and treatment.] / Complicaciones vasculares del trasplante renal. Diagnóstico y tratamiento.

Vascular complications remain common after renal transplantation, occurring in 3% to 15% of patients. These complications can compromise graft function,with graft loss rates ranging from 12.6 to 66.7%.Vascular abnormalities of the graft, specifically the presence of multiple vessels, represent the most frequently studied risk factor for the development of vascular complications. Other risk factors identified for the development of vascular complications are linked to the characteristics of the recipient, or thromboembolic diseasesharing atherosclerosis and/or hypercoagulant state aspathogenic features.Although the most frequent vascular complication is renal artery stenosis, we will also address the complications according to their early or late on set in order to highlightthe potentially more severe complications that may affectgraft survival during the follow-up period.Early vascular complications include mainly arterial and venous thrombosis and lacerations or disruptions of artery and/or vein, as well as arterio-venous fistulas or intrarenal pseudoaneurysms. In contrast, late-onset complications include stenosis or kinking of the renal artery-and less commonly of the renal vein-, as well as extrinsic compression as a consequence of the presence of perigraft fluid collections. Finally, extrarenal pseudoaneurysm is a potentially severe complication in the late post-transplant period.Finally, this article explores special transplant situations such as complications derived from the paediatric donor in adult recipients, transplantation in the paediatric recipient and emerging techniques like robotic renal transplantation.

Las complicaciones vasculares siguen siendo frecuentes después del trasplante renal, ocurriendo entre el 3% y el 15% de los pacientes. Estas complicaciones pueden comprometer la función del injerto,con unas tasas de pérdida del injerto que varían entreel 12,6 ­ 66,7%.Las anomalías vasculares del injerto, y concretamente la presencia de múltiples vasos, representan el factor de riesgo más frecuente y estudiado para el desarrollo de complicaciones vasculares. Otros factores de riesgo de complicaciones vasculares se han relacionado con las características del receptor, o la enfermedad tromboembólica, compartiendo como características patogénicas la aterosclerosis y/o el estado hipercoagulante. Aunque la complicación vascular más frecuente está constituida por la estenosis de la arteria renal, expondremos las complicaciones en función de su presentación clínica temprana o tardía en un intento de destacar para el lector las complicaciones potencialmente más severas y que en cada momento del tiempo pueden condicionar la supervivencia del injerto.Las complicaciones de presentación preferentemente perioperatoria incluyen fundamentalmente la trombosis arterial y venosa y las laceraciones o disrupciones de arteria y/o vena, así como las fístulas arterio-venosas opseudoaneurismas intrarrenales. Por el contrario, otras complicaciones tienen comúnmente una presentación clínica más tardía. En este grupo incluimos la estenosiso acodamiento de la arteria renal y excepcionalmente de la vena renal, así como la compresión extrínseca de los vasos del injerto como consecuencia de la presencia de colecciones peri-injerto. Finalmente, una complicación severa que puede manifestarse de forma tardía enla evolución del receptor, es el pseudoaneurisma extrarrenal. Finalmente, haremos brevemente referencia a situaciones especiales del trasplante como las complicaciones derivadas del donante pediátrico en receptores adultos,del trasplante en el receptor pediátrico y de técnicas emergentes como el trasplante renal robótico.