Background: Arteriovenous Fistula (AVF) surveillance is required to detect early dysfunction (thrombosis, stenosis) and its timely correction prolongs access-patency. Clinical examination (CE) and doppler have been used as screening/surveillance of AVF, for early detection of AVF dysfunction. Since there was inadequate evidence for KDOQI to make recommendations on AVF surveillance and on secondary failure rate. We compared CE, doppler and fistulogram as surveillance modalities in detecting a secondary failure in matured AVF. Methodology: This prospective-observational, single-center study, was done between December 2019-April 2021. CKD stage 5 patients on dialysis/Not-on-dialysis with matured AVF were included at third month. CE, doppler (blood flow, vein diameter, depth), and fistulogram were done at third and sixth month. Secondary failure was assessed at sixth month classifying AVF to patent/functional and failed group. Diagnostic tests were performed by comparing three methods considering fistulogram as gold-standard. Residual urine output is also monitored to look for any contrast induced residual renal function loss. Results: Of total 407 created AVF, 98 (24%) had primary failure. Twenty-five (6%) had surgical complications including unsuccessful AVF and aneurysm/rupture, 156 lost follow-up at third month, 104 consented patients were enrolled, 16 lost to follow-up subsequently, and 88 patients’ data were analyzed at the end. At the sixth month, 76(86.4%) had patent AVF, 8 (9.1%) had secondary failure (Thrombosis-4, Central Venous Stenosis-4), and 4 (4.1%) patients expired. Considering fistulogram as a diagnostic standard, CE showed 87.5% sensitivity, and 93.4% specificity (cohen’s kappa value of 0.66). Doppler had sensitivity and specificity of 87% and 96% respectively (cohen’s kappa value of 0.75), Combination of clinical examination with doppler showed sensitivity and specificity of 100% and 89% respectively. Conclusion: Although the secondary AVF failure rate is less than the primary, CE is an important and valuable tool in the diagnosis and surveillance of AVF in detecting its dysfunction. Moreover, CE with doppler can be used as a surveillance protocol that can detect early AVF dysfunction at par with Fistulogram.

End-stage kidney disease (ESKD) patients who were on maintenance hemodialysis require a stable, permanent vascular access as a lifeline. Venous mapping during prearteriovenous fistula (AVF) construction does not include central vein assessment. The guidelines on angiographic assessment of central veins during pre-AVF construction are yet to be streamlined. Moreover, during COVID pandemic, assess difficulty in catheterization laboratory and interventional radiology created devastating situation. We report 15 ESKD cases of central venous stenosis presented during the COVID pandemic time from February 2020 to July 2021. Patients' basic details were collected and initial clinical examination findings were recorded; they were subjected to Doppler and fistulogram. After the combined decision of nephrologist, interventional cardiologist, and vascular surgeon, the management (fistula closure/repair) was planned. Of 15 patients, 13 were males. Basic disease is chronic glomerulonephritis in 9, diabetic nephropathy in 4, and chronic interstitial nephritis in 2. Average number of central vein cannulation prior to AVF creation was 2.6. The median time to the development of symptoms after fistula creation was 13 months. Major initial symptoms were swelling of the upper limb in 4, dilatation of outflow veins in 5, swelling and dilatation in 2, poor flow during dialysis in 3, and dilatation of neck and chest vein in 1. Arm elevation test was positive in most of the cases. On Doppler assessment, dilated veins (>12 mm) with high outflow (>2000 ml/min) in 5, 4 patients showed low flow (<400 ml/min), and six patients showed normal findings. In fistulogram, the common location of stenosis/thrombosis was brachiocephalic vein (BV) in 5 and subclavian vein (SC) in 3, BV vein + SC vein in 4, and superior vena cava in 3. Out of 15, 3 underwent balloon dilatation, 7 underwent fistula closure, 1 no intervention done, 3 lost to follow-up, and 1 expired. This is the first case series of central vein stenosis (CVS) brought in light during COVID pandemic. CVS is a serious issue, which might result in permanent vascular access failure. Further study is needed on impact of previous central vein catheterization leading to stenosis and role of pre-AVF creation angiographic assessment to avoid this type of devastating AVF complication.

Minimal change disease has been associated with different types of vaccinations, and several case reports have associated the development of this disease with COVID vaccinations as well. We present here a case report of a 19-year-old male who developed minimal change nephrotic syndrome following the second dose of Covishield ChAdOx1 nCoV vaccine. He had received his first dose 2 months prior which was uneventful. He developed fever 3 days after second vaccination and 1 week later developed edema, frothuria, and oliguria. His reports showed a 24-h urine protein of 3.7 g per day, serum creatinine of 1.9 mg/dL, and serum albumin of 1.9 g/dL. He underwent a kidney biopsy which showed features consistent with minimal change disease. He was started on prednisolone at 1 mg/kg body weight. He responded well to treatment and attained complete remission after 33 days of steroids with 24-h urine protein of 195 mg/day, serum creatinine of 0.6 mg/dL, and serum albumin of 5.1 g/dL. This case highlights the possibility of occurrence of minimal change disease post Covishield vaccination even after the second dose despite an uneventful first dose.

A 35-year-old gentleman who was on maintenance hemodialysis for last 20 months presented with progressive swelling of the left upper limb. Initially, he had right nontunneled internal jugular vein (IJV) catheter followed by left nontunneled IJV catheter through which he received dialysis for 2 months. Further, his left brachiocephalic fistula (BCF) was created 18 months back. Since then, he was on regular thrice weekly dialysis through BCF. He started developing swelling of the left upper limb 8 months after fistula creation, which was gradually increasing. Blood flow was found to be normal during dialysis, examination suggestive of entire left upper limb swelling with thick induration. Doppler showed dilated outflow veins with high flow without any narrowing/stenosis of veins. Computed tomography venography done showed left brachiocephalic vein stenosis. He was found to have mega-fistula secondary to central vein stenosis which was managed successfully being discussed in this case report. Undiagnosed occult central venous stenosis in the prearteriovenous fistula (AVF) construction can manifest in various ways; one of them is as mega-fistula. It is the generalized aneurysmal dilatation of the entire outflow vessels of an AVF. Management option for this condition is limited depending on the etiology, fistula flow has to be reduced either by banding of the vessel or by fistula closure. Assessment of central veins before AVF construction and regular access surveillance in dialysis patients may prevent complications like these.