Diabetic nephropathy: Is it time yet for routine kidney biopsy?

Table 1 Diabetic nephropathy stages

Stage 1 Early hyperfunction and hypertrophy	ACR < 30 mg/g creatinine
Stage 2 Morphologic lesions without signs of clinical disease	ACR > 30 and < 300 mg/g creatinine
Stage 3 Microalbuminuria	ACR > 300 mg/g creatinine and/or persistent
	proteinuria with serum concentration of creatinine 2.0 mg/dL
Stage 4 Overt nephropathy	Serum concentration of creatinine 2.0 mg/dL with proteinuria
Stage 5 End-stage renal disease with uremia	On dialysis

ACR: Albumin to creatinine ratio.

Table 2 Comparison of diabetic nephropathy and non-diabetic renal disease prevalence reported in the literature

Ref.	Country	Population	Type 1 or 2 DM	% DN	% NDRD	% Mixed
Mazzucco et al[23]	Italy	393	2	39.7	43	17.3
Christensen et al[24]	Denmark	51	2	68.6	13.8	NR
Zhang et al[37]	China	130	2	73.9	26.1	NR
Zhuo et al[50]	China/Japan	216	2	6.5	82.9	10.7
Sharma et al[51]	United States	620	2	37	36	27
Hironaka et al[52]	Japan	35	1 and 2	71.4	14.3	14.3
Wong et al[53]	China	68	2	35	46	19
Prakash et al[55]	India	23	2	56.5	30.5	13
Mak et al[56]	China	51	2	67	16	17
Biensebach et al[57]	Austria	84	2	78.5	21.5	NR
Richards et al[58]	United Kingdom	68	1 and 2	61	32	3
Parving et al[59]	Denmark	35	2	77.1	20	2.9
Cordonnier et al[60]	United Kingdom	26	2	85	15	NR
Nzerue et al[61]	United States	31	2	41.9	19.4	38.7
Lee et al[62]	South Korea	22	2	36.4	50	13.6
Izzedine et al[63]	France	21	1 and 2	62	38	NR
Castellano et al[64]	Spain	20	2	45	55	NR
Serra et al[65]	Spain	35	2	74.3	17.2	8.5
Premalatha et al[66]	India	18	2	50	50	NR
Rychlík et al[67]	Czech Republic	163	2	42.4	47.5	10.1
Tone et al[68]	Japan	97	2	36	16.5	47.5
Moger et al[69]	India	26	2	34.6	23.1	42.3
Soni et al[70]	India	160	2	42.5	27.5	30
Pham et al[71]	United States	233	2	27.5	53.2	19.3
Kharrat et al[72]	Tunisia	72	2	34.1	69.5	NR
Akimoto et al[73]	Japan	50	2	68	26	6
Huang et al[74]	China	52	2	55.7	38.5	5.8
Lin et al[75]	Taiwan, China	50	2	48	22	30
Ghani et al[76]	Kuwait	31	2	54.8	NR	45.2
Arif et al[77]	Pakistan	73	2	27.3	49.3	NR
Hashim Al-Saedi et al[78]	Iraq	80	1 and 2	NR	NR	100
Mou et al[79]	China	69	2	47.8	52.2	NR
Haider et al[80]	Austria	567	1 and 2	68	17.4	NR
Chang et al[81]	South Korea	119	2	36.2	53.8	10
Bi et al[82]	China	220	2	54.5	NR	45.5
Chong et al[83]	Malaysia	110	2	62.7	18.2	19.1
Harada et al[84]	Japan	55	2	54.5	34.5	10.9
Oh et al[85]	South Korea	126	2	39.7	51.6	8.7
Yaqub et al[86]	Pakistan	68	2	31	52	17

DN: Diabetic nephropathy; NDRD: Non-diabetic renal disease; DM: Diabetes mellitus.