Progression of Kidney Damage in Balkan Endemic Nephropathy: A 15-Year Follow-Up of Patients with Kidney Biopsy Examination

Figures & data

Table 1. Basic data of BEN patients

	Age (years)		Proteinuria (mg/L)		Hemoglobin (g/dL)		Systolic blood pressure (mmHg)		Diastolic blood pressure (mmHg)
	At biopsy	Last exam	At biopsy	Last exam	At biopsy	Last exam	At biopsy	Last exam	At biopsy	Last exam
BEN without RF	54.8 ± 7.8	69.8 ± 6.5	182 ± 47	175 ± 84	14.1 ± 0.73a	12.6 ± 1.16b	125.8 ± 11.1	148.3 ± 11.6	88.3 ± 5.1	91.6 ± 2.7
BEN with incipient RF	54.1 ± 3.7	69.4 ± 5.7	177 ± 64	280 ± 95	11.9 ± 1.48	10.8 ± 1.64	145.0 ± 18.9	142.1 ± 9.94	90.7 ± 9.3	90.1 ± 9.0
BEN with advanced RF	59.0 ± 3.5	67.6 ± 4.9	235 ± 31	106 ± 28	10.1 ± 0.23	8.90 ± 0.68	145.0 ± 15.1	145.9 ± 11.3	91.4 ± 5.9	92.3 ± 6.2

Values are mean ± SD; RF, renal failure.

^aVersus groups 2 and 3, p< 0.05.

^bVersus group 3, p< 0.05.

Table 2. Renal size and function of BEN patients

	Left kidney (cm)		Right kidney (cm)
	At biopsy	Last exam	At biopsy	Last exam	^99mDTPA clearance (mL/min/1.72 m^2)	Yearly decrease of GFR (mL/min)
BEN without RF	12.1 ± 0.4	11.7 ± 0.5	12.4 ± 0.6	12.0 ± 0.7	103.5 ± 21.3	1.89
BEN with incipient RF	11.4 ± 0.6	10.7 ± 1.2	11.1 ± 0.8	10.1 ± 1.1	65.5 ± 11.3	3.10
BEN with advanced RF	10.0 ± 1.2a	8.9 ± 0.9b	10.1 ± 1.1a	8.8 ± 1.0a	28.0 ± 6.2c	3.31

Values are mean ± SD; RF, renal failure.

^aVersus groups 1 and 2, p< 0.05.

^bVersus group 1, p< 0.05.

^cVersus groups 1 and 2, p< 0.01.

Table 3. Renal interstitial capillaries in different stages of BEN

	Number of cap per 0.1 mm^2	Length density of cap in mm^2	Area of cap per 0.1 mm^2× 10^3 µm^2	Mean area of cap in µm^2
Control	43 ± 2	862 ± 40	3.51 ± 0.39	81 ± 7
BEN without RF	36 ± 5a	720 ± 100a	2.85 ± 0.40	78 ± 10
BEN with incipient RF	20 ± 6b	420 ± 115b	1.41 ± 0.21b	68 ± 9
BEN with advanced RF	17 ± 5b	350 ± 120b	1.15 ± 0.16b	61 ± 4c

Values are means ± SD; RF, renal failure; cap, capillaries.

^aVersus group 1, p< 0.01.

^bVersus group 1, p< 0.001.

^cVersus group 1, p< 0.05.

Figure 1. Varying extent of kidney cortex damage in two BEN patients. (A) Small scattered areas of discrete interstitial sclerosis with apparently normal tubuli. Segmental widening of the mesangium and discrete periglomerular sclerosis. Trichrom Masson × 100. (B) Discrete interstitial sclerosis and apparently normal proximal tubular epithelial cells on a larger magnification. A small arterial blood vessel with a thickened, partly hyalinized wall and narrowed lumen, similar to that in benign nephroangiosclerosis. Trichrom Masson × 200. (C) Larger areas of acellular interstitial sclerosis accompanied by tubular atrophy. Two glomeruli are seen: one in advanced sclerosis and the other with widening of the mesangium. Marked periglomerular sclerosis. Trichrom Masson × 100. (D) Juxtamedullary cortex with advanced acellular interstitial sclerosis and tubular atrophy. Trichrom Masson × 100.