Renal biopsy: Still a landmark for the nephrologist

Table 1 List of Indications for renal biopsy

Nephrotic syndrome

Acute kidney injury (when rule out obstruction, and pre-renal causes)

Systemic disease with renal dysfunction (in diabetic patients only if it presents with atypical features)

Non-nephrotic proteinuria, and in some circumstances isolated microscopic hematuria

Unexplained chronic kidney disease

Familial renal disease (may avoid biopsy in other family members affected)

Renal transplant dysfunction

Table 2 Types of complications after renal biopsy

Minor complications	Major complications
Bleeding	Bleeding
Asymptomatic haematoma	Hematoma requiring blood transfusion or invasive procedure to stop bleeding
Microscopic and gross haematuria	Urinary tract obstruction with or without AKI
Anaemia (drop in haemoglobin concentration ≥ 1 g/dL)	Hypotension related to bleeding
Pain (> 12 h)	Nephrectomy
Page kidney	Sepsis
Perinephric infection	Other organs and/or blood vessels perforation
Arteriovenous fistula	Death

AKI: Acute kidney injury.

Table 3 List of main studies (> 500 biopsies) reporting minor, major complications and mortality rate after renal biopsy

Ref.	Year of publication	No. of biopsies	% Minor complications	% Major complications	% Mortality
Fenerberg et al[24]	1998	1081	9.6	1.11	0.09
Prasad et al[28]	1998	1090	3	0.36	0
Preda et al[20]	2003	515	9.5	2.7	0
Whittier et al[51]	2004	750	6.7	6.4	0.13
Atwell et al[44]	2010	5832	-	0.7	0
Stratta et al[29]	2007	1137	24.2	0.36	0
Korbet et al[23]	2014	1055	8.1	6.6	0.09
Mai et al[21]	2013	934	5.9	0.86	0
Tøndel et al[13]	2012	9288	1.9	0.9	0
Prasad et al[28]	2015	2138	5.4	5.1	0