PURPOSE: The aim of this study was to evaluate the clinical usefulness of measurement of beta2 microglobulin (beta2 MG), N-acetyl-beta-D-glucosaminidase (NAG) of spot urine samples as indices of renal tubular damage and microalbumin of spot urine samples as a parameter of glomerular damage in children with vesicoureteral reflux (VUR) or renal defects. METHODS: We studied 91 children with previous UTI. The children were classified as 62 children without VUR and renal defects (group I), 10 children with VUR, without renal defects (group II), and 19 children with VUR and renal defects (group III). Patients having VUR were separated according to the degree of VUR (mild VUR: VUR grade I-III, severe VUR: VUR grade IV-V). Urinary excretion of beta2 microglobulin (beta2 MG), microalbumin, N-acetyl-beta-D-glucosaminidase (NAG), creatinine were measured in samples of morning urine specimens. Children with VUR or renal defects detected by voiding cystourethrography (VCUG) and DMSA renal scan were investigated. RESULTS: Microalbumin/Cr ratio of spot urine was significantly increased in group III compared group I (42.3+/-27.2 mg/gCr vs 25.2+/-10.9 mg/gCr, P<0.05). NAG/Cr ratio of spot urine was significantly increased in group II compared group I (3.70+/-23.4 mg/gCr vs 18.7+/-12.7 mg/gCr, P<0.05). There was no statistically significant difference of beta2 MG/Cr ratio among three groups. CONCLUSION: Urinary microalbumin excretion of morning urine sample may be a simple and reliable clinical indicators for early identification of renal damage in children with VUR and renal defects. Urinary microalbumin excretion may be useful marker to predict the the severity of VUR.
Acetylglucosaminidase ; Child ; Creatinine ; Humans ; Succimer ; Vesico-Ureteral Reflux

BACKGROUND: Routine renal function tests are not sensitive enough to detect early renal complication of diabetes. To detect the complication as soon as possible, we measured urine N-Acetyl-beta-D-glucosaminidase(NAG) and evaluated in comparison with microalbumin and beta2-microglobulin(beta2-MG). METHODS: 87 patients with type II diabetes visited Catholic University Hospital of Taegu Hyosung during the period October 1995 to March 1996. We collected 24 hour urine samples and measured NAG, albumin excretion rate (AER), beta2-MG. urinalysis, BUN, creatinine(Cr) Cr clearance(CrCl), fasting and 2 hour postprandial blood sugar and hemoglobin A1c. RESULTS: The average age of the patients was 53+/-15 years old and their average disease duration was 5.8+/-5.0 years. Abnormal rates of each renal function tests were as follows : NAG/gCr 52.1%, AER 51.7%, CrCl 42.5%, BUN 18.4%, beta2-MG 13.8% and creatinine 6.9% in order. From 36 patients whose AER was within normal limit, 13 of them(36.1%) showed increased level of NAG/gCr. Of 38 patients with increased NAG/gCr results, the 31 patients (81.6%) recorded abnormal results of renal function tests. Among 87 patients studied 60 patients(68.5%) showed increased level of NAG/gCr or AER results. Compared with AER test alone. the combined tests with NAG/gCr increased 16.8% of detection rates of renal complication in type II diabetes. CONCLUSION: Urine NAG/gCr and AER tests were very useful for detecting the early renal complication of type n diabetes. As increase of NAG/gCr suggest the proximal tubule damage, it is necessary to have further evaluation about the proximal tubule damage of renal complication in type II diabetes.
Acetylglucosaminidase* ; Blood Glucose ; Creatinine ; Daegu ; Fasting ; Humans ; Urinalysis

NAG activity has been measured in the urine of hypertension, diabetes mellitus and renal disease subjects. Results have shown significantly higher levels of Urinary NAG in hypertension, diaetes and renal disease subjects compared to normal control Subjects group(P<0.001). Urinary NAG measurement is simple and accurate and it provides a valuable information in the early detection of renal dysfunction in hypertension and diabetes subjects and also in the follow up of these patients.
Acetylglucosaminidase* ; Diabetes Mellitus* ; Follow-Up Studies ; Humans ; Hypertension*

PURPOSE: Considering that renal biopsy is not routinely indicated in nephrotic syndrome in children and the risk of the procedure, we studied that it is possible to predict steroid responsiveness in nephrotic syndrome and the difference in responsivenss is related with the histopathologic type using urinary beta2-microglobulin and N-Acetyl-beta-D-Glucosaminidase activity as a safe and noninvasive method. METHODS: We measured serum creatinine, albumin, cholesterol and urinary creatinine, protein, B2M, NAG at the time of admission and after 2 weeks of treatment in 37 cases of primary nephrotic syndrome in children who were admitted to the Pediatric department of Chung-Ang Medical Center between March 1, 1994 and June 30, 1996. RESULTS: The results were as follows : 1) When urinary B2M value of less than 1000microgram/g creatinine was used as the cut-off value, the test identified steroid responsiveness with a sensitivity of 100%, a specificity of 80%. When urinary NAG activity of less than 100U/hr/mg creatinine was used as the cut-off value, the test identified steroid responsiveness with a sensitivity of 100%, a specificity of 81.8%. 2) Pretreatment urinary B2M levels in Good-response and Poor-response group were 559.8+/-718.5microgram/g creatinine, 3599.1+/-4956.7microgram/g creatinine, respectively. There was statistical significance between the two groups (P<0.05). 3) Pretreatment urinary NAG activity in Good-response and Poor-response group were 42.6+/-23.6U/hr/mg creatinine, 79.6+/-80.1U/hr/mg creatinine, respectively. There was statistical significance between the two groups (P<0.05). CONCLUSIONS: In conclusion, measurement of urinary B2M level and NAG activity for early detection of renal tubular damage is helpful in prediction of steroid responsiveness of primary nephrotic syndrome. If the urinary B2M level and NAG activity are elevated, the patient is suspected to steroid resistance. Therefore, prolonged steroid therapy should be avoided in such patients because of their greater chance of not responding. This approach would reduce the many serious side effects of prolonged treatment in patients who are unlikely to benefit.
Acetylglucosaminidase* ; Biopsy ; Child ; Cholesterol ; Creatinine ; Humans ; Nephrotic Syndrome* ; Sensitivity and Specificity

PURPOSE: Urinary N-acetyl-beta-D-glucosaminidase(NAG) and beta 2-microglobulin(B2M) is considered to be a marker of tubulointerstitial injury. The aim of this study was to examine the urinary levels of NAG and B2M in children with various renal diseases. METHODS: We studied 21 children(8.9+/-4.5 years, Male:Female=14:7) and they were divided into three groups: group I(steroid-sensitive nephrotic syndrome-4 patients), group II(various kinds of glomerulonephritis-4 patients), and group III(normal urinalysis or non-glomerular renal diseases-13 patients). RESULTS: Urinary NAG levels in groups I and II were significantly higher than those in group III(19.4+/-11.5 and 30.0+/-30.1 vs. 4.7+/-3.9, P=0.01), while urinary B2M levels did not differ among the 3 groups, although urinary NAG levels were positively correlated with urinary B2M levels(r=0.49, P=0.03). Urinary NAG and B2M levels were all correlated with proteinuria(r=0.79, P<0.001 and r=0.68, respectively, P=0.001) serum albumin(r=-0.72, P<0.001 and r=-0.57, respectively, P=0.01) and cholesterol(r=0.58, P=0.006 and r=0.56, respectively, P=0.013) levels. Conclusions: Urinary excretions of NAG and B2M are increased in children with steroid-sensitive nephrotic syndrome and various kinds of glomerulonephritis, suggesting tubular dysfunction might be present in these diseases.
Acetylglucosaminidase ; beta 2-Microglobulin ; Child ; Glomerulonephritis ; Humans ; Nephrotic Syndrome ; Urinalysis

In this study, we measured the activity of the erythrocyte pyrimidine 5'-nucleotidase (P5N) and urinary N-acetyl-beta-D-glucosaminidase (NAG) from 154 workers exposed to lead and 43 workers not exposed. We analyzed the correlation of the P5N activity and NAG activity with other biological exposure indices of lead such as blood lead (PbB) and zinc protoporphyrin (ZPP). The measurement was performed by using high performance liquid chromatography (HPLC), spectrophotometer and atomic absorption spectrophotometer. The results are as follows: 1. The mean value of P5N activity for workers exposed to lead was 9.50+/-.13 micromol uridine/hr/g Hb and 11.60+/-.2 micromol uridine/hr/g Hb for workers not exported. The P5N activity showed a normal distribution, but the other indices of lead showed logarithmic normal distributions. 2. The P5N activity and ZPP were decreased as PbB wag increased. But the NAG activity had no correlation with changes of PbB. 3. The correlation coefficients of the P5N activity with other biological exposure indices of lead such as PbB, ZPP, NAG activity were -0.72, -0.55, and 0.05, respectively. We speculated that the P5N activity can be used as a reliable biological exposure index of lead but NAG activity can be used as a biological management index of lead.
5'-Nucleotidase* ; Absorption ; Acetylglucosaminidase* ; Chromatography, Liquid ; Erythrocytes* ; Zinc

In order to identify the necessary information of biochemical indices for renal effect of lead for the early detection in medical surveillance of lead worker, the reference values of urinary N-acetyl-beta-D-glucosaminidase(NAG) activities were studied with 205 office workers in one industrial complex area who were not exposed to lead occupationally. While study variables selected for lead exposure were blood lead (pbB), blood zinc protoporphyrin(ZPP) and delta-aminolevulinic acid (DALA) in urine, those for renal effect were urinary N-acetyl-beta-D-glucosaminidase(NAG), blood urea nitrogen(BUN), serum creatinine(cr), serum uric acid (Ua), and urinary total protein (U-Tp). The results obtained were as follows: 1. The mean values of blood lead, ZPP and DALA in all subjects were 14.39+/-4.02 microgram/dl, 21.61+/-8.00 microgram/dl, and 2.73+/-0.90 microgram/l respectively. 2. The mean value of urinary NAG activities in all subjects was 3.51+/-2.01 U/l. The mean value of urinary NAG activities, which calculated from NAG activities divided by urinary creatinine concentration (CNAG), was 5.42+/-5.53 U/g creatinine and logarithmic normal distributed. 3. The reference value of urinary NAG activity was 12.06 U/g creatinine (95% CI=10.57-14.76U/g creatinine). 4. Logarithmic CNAG(r=0.781 P<0.01), U-TP(r=0.670 p<0.01) and ZPP (r=0.172 p<0.05)showed statistically significant correlation with CNAG.
Acetylglucosaminidase* ; Aminolevulinic Acid ; Creatinine ; Occupations ; Reference Values ; Urea ; Uric Acid ; Zinc

The influence of lead exposure on renal function was studied. Three hundred forty two male lead exposed workers who worked in 3 storage battery factories, 5 secondary smelting factories and 3 litharge making factories, and 60 male control workers who were not exposed to lead occupationally were chosen for this study. Blood lead (PbB), zinc protoporphyrin in whole blood (ZPP) and delta-aminolevulinic acid in urine (DALA) were selected as indicators of lead exposure. As indicators of renal function blood urea nitrogen(BUN) , serum creatinine(S-Cr), serum uric acid (S-UA), N-acetyl-beta-D-glucosaminidase in urine (NAG) and urine protein (U-TP) were selected. While the mean values of lead exposure indicators of lead workers were significantly different from non-exposed ones, the mean values of renal function indicators of exposed except S-UA were significantly different from non-exposed. The frequency of workers whose value of renal function indicators were over the nor mal criteria (BUN>20 mg/dl ; S-Cr>1.2 mg/dl ; S-UA>7.0 mg/dl ; NAG>8.0 U/liter; U-TP>8.0 mg/dl) by the level of lead absorption in terms of PbB, ZPP and DALA were calculated. Age adjusted odds ratio of over the normal value of BUN and NAG were statistically significant by the level of ZPP and that of BUN only showed the dose-dependant relationship. But the frequency of over the normal criteria of renal function indicators were not increased by the level of PbB and DALA. On stepwise multiple regression using renal function indicators as a dependent variable and each lead exposure indicator and age as independent variables, only BUN, NAG and U-TP were contributed by the lead exposure indicators. It was found that only NAG of renal function indices was most reliable indicator who showed dose-response relationship with lead exposure and the measurement of NAG for lead workers whose relatively high exposure is highly recommended.
Absorption ; Acetylglucosaminidase ; Aminolevulinic Acid ; Humans ; Male ; Occupations* ; Odds Ratio ; Osmeriformes ; Reference Values ; Urea ; Uric Acid ; Zinc

To provide the basic for assessment of renal dysfunction related to silicosis, urinary N-acetyl-beta-D-glucosaminidase(NAG) activity known as a sensitive markers for early renal damage were measured in 58 silicosis patients, and control subjects of 40 pulmonary tuberculosis patients and 51 official workers. The results were summarized as follows. 1. The values of blood urea nitrogen and serum creatinine in all subjects were within reference limits. But the mean value of urinary NAG activity(7.25+/-7.31 U/g creatinine) was beyond reference value and more sensitive test than others. 2. The mean value of urinary NAG activity in silicosis group was 11.98+/-9.05 U/g creatinine and significantly higher than in tuberculosis and healthy group(p<0.01), but the mean values of NAG activity in tuberculosis and healthy group were not different(p>0.05). 3. The value of NAG activity in tuberculosis had a tendency to be increased according to severity of disease, but that was not significant(p>0.05). The value of NAG activity was increased significantly by use of nephrotoxic antituberculosis drugs(p<0.05). 4. The value of NAG activity in silicosis had a tendency to be increased according to the size of nodule, use of nephrotoxic antituberculosis drugs and shortness of onset duration, but the increase was not significant(p>0.05). 5. After excluding the users of nephrotoxic antituberculosis drugs, the mean values of NAG activity in healthy control and in tuberculosis control were same as 3.63 U/g creatinine and 3.60 U/g creatinine, respectively. But the mean value of NAG activity in silicosis group was remarkably increased as 10.90 U/g creatinine(p<0.01). As above results, even though there are no abnormal findings in screening renal function test, silicosis can be related with renal dysfunction. And it will be very useful to apply urinary NAG activity in health management of workers exposed to dust.
Acetylglucosaminidase* ; Blood Urea Nitrogen ; Creatinine ; Dust ; Humans ; Mass Screening ; Reference Values ; Silicosis* ; Tuberculosis ; Tuberculosis, Pulmonary

BACKGROUNDS: N-acetyl-beta-D-glucosaminidase (NAG) is one of many enzymes that exist in the renal proximal tubular cells. It is said that functional impairment of renal tubule can be detected by checking NAG in the urine. But, it has never been known whether urinary NAG value can be used as a predictor for the prognosis of patients with glomerulonephritis. In this study, we evaluated the relationship between urinary NAG level and the degree of injury in cortical interstitium which has been known to influence the prognosis of renal function in glomerulonephritis closely. METHODS: Before renal biopsy was performed in each patient, urinary NAG(isoenzyme A and B), urinary beta2-microglobulin, serum blood urea nitrogen (BUN), serum creatinine, serum albumin, creatinine clearance and 24 hour urinary protein excretion were measured. Then, we calculated volume density of cortical interstitium [Vv(i/c)] in each specimen using point count morphometry method after getting a confirmative diagnosis from pathologist. Simple correlation analysis and multivariate regression analysis were carried out. RESULTS: The number of total patients was 32(male:16), whose median age was 60(32-80). Vv (i/c) had significant correlation with serum creatinine, creatinine clearance and serum BUN. But it was not correlated well with urinary NAG and urinary beta2-microglobulin. Urinary NAG concentration(2.131 2.549unit/mmol Cr) was higher than that of normal control and showed significant correlation with urinary beta2-microglobulin, serum albumin and 24 hour urinary protein excretion in patients. CONCLUSION: Urinary NAG had no significant correlation with Vv(i/c) that has been known as an important prognostic factor for the renal function in glomerulonephritis, but had significant correlation with urinary protein excretion. We concluded that urinary NAG was not regarded to be an appropriate marker for predicting the prognosis of renal function in patient with glomerulonephritis.
Acetylglucosaminidase ; Biopsy ; Blood Urea Nitrogen ; Creatinine ; Diagnosis ; Glomerulonephritis* ; Humans ; Prognosis ; Serum Albumin