The risks associated with percutaneous native kidney biopsies: a prospective study.

BACKGROUND: The known risks and benefits of native kidney biopsies are mainly based on the findings of retrospective studies. The aim of this multicentre prospective study was to evaluate the safety of percutaneous renal biopsies and quantify biopsy-related complication rates in Italy. METHODS: The study examined the results of native kidney biopsies performed in 54 Italian nephrology centres between 2012 and 2020. The primary outcome was the rate of major complications 1 day after the procedure, or for longer if it was necessary to evaluate the evolution of a complication. Centre and patient risk predictors were analysed using multivariate logistic regression. RESULTS: Analysis of 5304 biopsies of patients with a median age of 53.2 years revealed 400 major complication events in 273 patients (5.1%): the most frequent was a ≥2 g/dL decrease in haemoglobin levels (2.2%), followed by macrohaematuria (1.2%), blood transfusion (1.1%), gross haematoma (0.9%), artero-venous fistula (0.7%), invasive intervention (0.5%), pain (0.5%), symptomatic hypotension (0.3%), a rapid increase in serum creatinine levels (0.1%) and death (0.02%). The risk factors for major complications were higher plasma creatinine levels [odds ratio (OR) 1.12 for each mg/dL increase, 95% confidence interval (95% CI) 1.08-1.17], liver disease (OR 2.27, 95% CI 1.21-4.25) and a higher number of needle passes (OR for each pass 1.22, 95% CI 1.07-1.39), whereas higher proteinuria levels (OR for each g/day increase 0.95, 95% CI 0.92-0.99) were protective. CONCLUSIONS: This is the first multicentre prospective study showing that percutaneous native kidney biopsies are associated with a 5% risk of a major post-biopsy complication. Predictors of increased risk include higher plasma creatinine levels, liver disease and a higher number of needle passes.

[Membranous glomerulonephritis with crescent overlapping]. / La Glomerulonefrite membranosa con sovrapposizione crescentica.

Acute crescentic transformation is a rare but well described event in patients with membranous glomerulonephritis. We report our experience with a 66-year-old Caucasian man presented for rapid decline in renal function. For nearly 10 years, he was suffering from hypertension and mixed sensori-motor polyneuropathy. He performed therapy with prednisone and azathioprine, suspended 1 year before presentation. Moreover, six months before presentation, laboratory tests showed a serum creatinine concentration 220 mol/L and a 24-h protein excretion 0,75 g/d. The physical examination showed oedema and severe hypertension; the 24-h protein excretion was 1,1 gr/d and creatinine concentration was 550.8 mol/L; ANCA and other immunological tests were negative. There was no evidence of SLE, infection or malignancy. The kidney biopsy highlighted a membranous GN with crescentic overlap. The patient was treated with steroid and cyclophosphamide. Because there was no sign of improvement after 2 months, we stopped the cyclophosphamide therapy and the patient started chronic haemodialysis treatment. Unlike membranous nephropathy, patients with superimposed crescentic glomerulonephritis appear to have a more aggressive clinical course. The importance of recognizing this group of patients with membranous nephropathy and crescentic glomerulonephritis is that immunosuppressive therapy may ameliorate the progression of renal damage and in some cases early treatment was associated with useful recovery of renal function.

[Renal involvement in Erdheim-Chester disease]. / Il coinvolgimento renale nella Malattia di Erdheim-Chester.

The Erdheim-Chester disease is a rare form of Langherans cells. Since 1987 it is distinguished from other istiocytosis previously identified. The diagnosis of the disease relies on defined radiological (bone imaging) and pathological (histiocytic infiltration) criteria. Bone disease is crucial but systemic manifestations are reported more frequently at onset. Renal involvement is always asymptomatic at onset of disease or in the follow-up. In this review we analyze the reports of the literature; we highlight 3 pathological mechanisms of renal involvement: renal and retroperitoneal infiltration, urinary tract obstruction, renal arteries stenosis. No treatment to date has demonstrated an improvement in survival of patients with EC. Renal involvement is therefore symptomatic (ureteral stenting, percutaneous nephrostomy) or is adopted a wait-and-see attitude.

Kidney involvement in a Wegener granulomatosis case.

Wegener Granulomatosis is a systemic Anti-Neutrophil Cytoplasmic Autoantibody-associated Vasculitis, affecting small-to-medium vessels. Clinical presentation with simultaneous involvement of kidney and upper and lower respiratory tract is unusual. We report an instructive case of WG, analyzing clinical course, laboratory, and radiological features, kidney, lung, and larynx histological pictures. Besides renal biopsy, nephrology team performed larynx and lung biopsies because of unusual clinical presentation, computed tomography chest examination, and relevant malignancy risk regarding following immunosuppressant therapy.

Does systematic preliminar colour Doppler study reduce kidney biopsy complication incidence?

While ultrasonography is widely performed prior to biopsy, colour Doppler examination is often used only to discover post-biopsy complications. Aim of this paper was to evaluate the usefulness of colour Doppler examination in planning the optimal site of puncture for renal biopsy. Present analysis includes 561 consecutive percutaneous renal biopsies performed from the same operator. Until August 2000 332 biopsies were performed after a preliminary ultrasonography (Group A). From September 2000, 229 patients underwent even a preliminary colour Doppler study (Group B). Postbioptic bleeding were categorized as minor (gross hematuria or subcapsular perinephric hematoma < 4 cmq of greater diameter) or major (hematoma >4 cmq of greater diameter; requiring blood transfusion or invasive procedures; leading to acute renal failure, urine tract obstruction, septicaemia, or death). Major complications were seen in 2.1% in Group A while in Group B only one case was reported (0.43%). Minor clinically significant complications occur in 7.8% in Group A and in 3.4% of cases of Group B. Colour Doppler reduced drastically the incidence of complications observed before the introduction of routine colour Doppler examination prior to biopsy. In our opinion, these data support the use of preliminary colour Doppler study when a biopsy is planned.