1603202
Eur. Urol. 4: 46-49 (1978)
Fibrinolytic Degradation Products in Urine of Anticoagulated Transplant Patients J.J. Aguilo, E.J. W. Bowie, J.E. Woods and C.A. Owen, jr. Mayo Clinic, Mayo Graduate School of Medicine, University of Minnesota, Rochester, Minn.
Abstract. A study of the level of urinary fibrinolytic split products in 14 renal transplant patients who received oral anticoagulants postoperatively revealed a tendency toward increased levels of fibrinolytic split products that were temporally related to graft rejection. The amount of fibrinolytic split products in the urine was positively related to the severity of rejection as well as to the final status of the allograft. Thus, the urinary level of fibrinolytic split products, as determined by the latex-coated particle test, can be used as an indicator of the course of warfarin-anticoagulated patients after renal allografting.
Key Words. Fibrin fibrinogen degradation products Fibrinolysis • Transplantation, homologous ■ Warfarin
fibrinogen split products levels were determined in the urine of renal transplant patients who were effectively anticoagulated. Materials and Methods 14 renal transplant recipients were studied. 9 received a kidney from a living relative and 5 received cadaveric kidneys. All but 1 patient were bilaterally nephrectomized before transplantation. Patients were anticoagulated with subcutaneous heparin (5,000 U every 12 h) from the time of transplant to the end of the 6th postoperative day; 48 h after renal allografting, oral anticoagulation with warfarin was begun. Prothrombin times, obtained daily for all patients, were in the therapeutic range, that is, over 17 sec (controls, 10—11 sec). In 1 patient (case 7), anticoagulation was discontinued after the presence of a perirenal hema toma was suspected. In 11 patients, daily urine samples were obtained; in 3 other patients, urine samples were obtained every other day. The samples of urine were collected, starting on the 7th day after transplantation, when the urine was free of detectable blood. Patients were studied from 9 to 47 days (average, 21 days). 2 ml of fresh urine were placed immedi ately in specially provided 3-ml rubber-plugged glass tubes. The tubes contained thrombin to clot any possible fibrin ogen and soybean trypsin inhibitor to inhibit degradation of fibrin or fibrinogen. After thorough mixing, samples were frozen at —20 C and were thawed just before testing. Urine was tested undiluted, diluted fivefold, and with further serial dilutions. A drop of each dilution was stirred with one drop of previously shaken latex suspension (con taining the antibody) with an applicator stick until the mixture appeared to be homogeneous. The slide was then rocked gently for 2 min and observed against a dark background for evidence of agglutination.
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After renal allografting, the rising levels of fi brinogen split products in urine have been used as a method of detecting the rejection phenomenon. It has been thought that after renal transplantation, anticoagulation with warfarin derivatives might de crease the amount of fibrinogen split products in the urine and thus interfere with the reliable detection of rejection by this method. To determine the relationships of anticoagula tion to levels of urinary fibrinogen split products and rejection, we studied 14 anticoagulated pa tients with renal allografts. The rapid latex-screen ing test was used to measure urinary fibrinogen split products levels. Several different methods of measuring fibrinogen split products levels in urine have been devised (3—5, 8, 9), but a practical one is the rapid latex-screening test (1, 9). This is a semiquantitative test and uses antibody-coated latex particles ( 1 ). We have used warfarin as the anticoagulant during the postoperative period after renal allo grafting for the last 3 years. The aim is to prevent embolic phenomena, not to prevent rejection. The use of warfarin anticoagulants as antirejection med ication is doubtful, or at least controversial (2). The present study represents the first in which
Fibrinogen Degradation in Urine of Anticoagulated Renal Transplants
47
Table I. Relationships of levels of fibrinogen split products, rejection, and allograft status in 14 anticoagulated renal transplant patients Case No.
Kidney Maximal donor fibrinogen type split products Mg/ml
Fibrinogen split products increased before rejection (days)
Decreased fibrinogen split products in relation to méthylprednisolone
Type of rejection
Allograft status
Increased sensitivity to warfarin when rejecting
13 9 14
3
LRD LRD LRD LRD CAD CAD CAD
no 2 no no2 no2 no2 no2 no
acute none none none none none chronic
LRD
20—< 40
no
yes
chronic
4
CAD
40—< 80
no
no
acute
5
LRD*1 l LRD
80— 160
yes (1) yes (6)
no no
acute acute
7
LRD
> 160
no rejection
no2
6
CAD
> 160
yes(3)
yes
acute tubular necrosis acute
good good good died3 good good lost at 4 months lost at 30 days lost at 23 days good lost at 40 days good
no
20—< 40 20—< 40 20—< 40 20—< 40 20—< 40
no no rejection no rejection no rejection no rejection no rejection yes (8)
2
1
LRD
> 160
yes (2)
yes
acute
11 10 8
12
l
10-< 20 10-< 20
lost at 30 days lost at 14 days
no yes yes no yes no anti coagulant yes yes
Samples that agglutinated undiluted urine were con sidered to contain fibrinogen split products in a concentra tion of more than 2 pg/ml. Progressively increasing dilu tions were considered to be positive in accordance with this rule. Positive and negative urine specimens were used as controls to be certain of the reliability of the method. 60 samples from 10 healthy adults were tested to establish the normal baseline. 9 of the 10 had a positive test on undiluted urine at one time or another (fibrinogen split products, >2;Ug/ml). 3 of these 9 occasionally exhibited positive results on 1:5 diluted urine (fibrinogen split prod ucts, > 10pg/ml) but none were positive in 1:10 diluted urine.
Results Significant elevation of fibrinogen split products levels in the urine (more than 20 Mg/ml) was seen in 12 of the 14 patients (table I). Of these 12 patients, 6 had fibrinogen split products concentra tions greater than 40 Mg/ml, 5 had higher than 80 Mg/ml, and 4 had higher than 160 Mg/ml.
Of the 2 patients with fibrinogen split products values less than 20 Mg/ml, one (case 13) had a transient episode of rejection without elevation of fibrinogen split products levels that was well con trolled by increased immunosuppressive treatment. The other patient (case 9) never had evidence of rejection. Both patients had normal creatinine levels after transplantation, 1 patient at 6 months and the other at 10 months. Of the 6 patients who had fibrinogen split products levels between 20 and 40 Mg/ml, 4 never had clinically significant rejection. 3 of the 4 continued to have good functioning grafts 9 months to 1 year after transplantation. The 4th patient died of unrelated causes; at the time of death, the serum creatinine level was 2.55 mg/dl. The other 2 patients had chronic rejection and lost their allografts — one 1 month and the other 4 months after transplantation. Of the 6 patients who had fibrinogen split products levels greater than 40 Mg/ml, 5 had acute
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LRD = Living related donor; CAD = cadaveric donor. 1 Collected on alternate days. 2 Never received a high dosage. 3 Unrelated causes.
Aguilo/Bowie/Woods/Owen, jr.
48
clinical rejection. One (case 7) had prolonged acute tubular necrosis and received anticoagulants only for the first 15 days after transplantation. Of the 6, only this patient and another patient (case 5) eventually recovered their kidney function; the other 4 lost their allografts 24-30 days after transplantation. 3 of the 4 patients had fibrinogen split products levels greater than 160jUg/mfi and acute rejection occurred without recovery of kid ney function in spite of energetic immunosuppres sive treatment (fig. 1).
Comments Our study revealed that 12 of the 14 patients had elevated urinary fibrinogen split products levels sometime after kidney transplantation (ex cluding the first 2 postoperative weeks) in spite of effective anticoagulation with warfarin. This is in contrast with results of previous reports (5, 6) which report a reduction in fibrinogen split prod ucts levels in the urine. 5 patients without clini cally significant rejection had levels of fibrinogen split products between 20 and 40 ßg/ml. High levels of fibrinogen split products in the urine were
References 1 Arocha-Pinango, C.L.: A comparison of TRCII and latex-particle tests for the titration of FR-antigen. J. clin. Path. 25: 757-761 (1972). 2 Barnes, A.D.; Coles, G.A.; White, H.J.O.: A controlled trial of anticoagulants in cadaveric renal transplantation. Transplantation 11: 491-494 (1974). 3 Bennett, N.M.: Bennett, D.; Holland, N.H.; Luke, R.G.: Serum fibrin degradation products in the diagnosis of transplantation rejection. Transplantation 14: 311—316 (1972). 4Carlsson, S.; Hedner, U.; Nilsson, I.M.: Kidney transplan tation and fibrinolytic split products in serum and urine. Transplantation 10: 366—371 (1970). 5 Cash, J.D.; Clarkson, A.R.: Serum and urinary fibrin/ fibrinogen degradation products in renal disease. Scand. J. Haematol. 13: suppl., pp. 331-336 (1971).
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Fig. 1. Case 12. Example of serum creatinine, urinary fibrinogen split products levels, and prothrombin time changes.
positively correlated with rejection and irreversible damage. Whether the donor source was a cadaver or a living relative did not seem to be significant. Of the 6 patients with fibrinogen split products levels greater than 40 jug/ml, 2 had received cadav eric kidneys and 4 had received living related donor kidneys. It has been observed that elevation of the uri nary fibrinogen split products levels frequently occurs several days before the rejection phenome non (6, 7, 9). In our series, elevation of fibrinogen split products levels (> 80 /xg/ml) occurred from 24 h to 6 days before clinical evidence of rejection. Our treatment for rejection includes an increase in the dosage of intravenous méthylprednisolone, with doses as high as 2 g and 500 mg, alternated daily, to a total dosage of 12—15 g, and 450 rad of radiation in three sessions (11). Antilymphocytic globulin is not included in our treatment protocol. High dosages of méthylprednisolone were related to decreases in the fibrinogen split products con centration in the urine in 2 of the patients who had fibrinogen split products levels greater than 160 Mg/ml. Patients with fibrinogen split products levels higher than 40 ßg/ml who had rejected their allo grafts appeared to be especially sensitive to warfa rin, as reflected by sudden prolongation of their prothrombin times to 40—50 sec (cases 1, 2, 4, 6, and 12). Although the reason for this is not known, it has been suggested that, even if there is no evidence of disseminated intravascular coagula tion or systemic fibrinolysis during rejection (3), the damaged renal tubule and arteriolar endo thelium with their well-known fibrinolytic poten tial (4, 10) may contribute to the prolongation of prothrombin times.
Fibrinogen Degradation in Urine of Anticoagulated Renal Transplants
lOWardle, E.N.; Menon, I.S.; Uldall, P.R.; Swinney, J.: Proteins and fibrinolysis in recipients of renal allografts. J. clin. Path. 24: 124-128 (1971). 11 Woods, J.E.; Anderson, C.F.; DeWeerd, J.H.; Johnson, W.J.; Donadio, J.V., jr.; Leary, F.J.; Frohnert, P.P.: High-dosage intravenously administered méthylpredni solone in renal transplantation. A preliminary report. J. Am. med. Ass. 223: 896-899 (1973).
Dr. J.J. Aguilo, Clinica Quiron, Avda. Virgen de Montserrat 5, Barcelona 12 (Spain)
Downloaded by: American University of Beirut - Jafet Library 193.188.128.21 - 6/11/2019 8:10:53 AM
6 Clarkson, A.R.; Morton, J.B.; Cash, J.D.: Urinary fibrin/ fibrinogen degradation products after renal homotrans plantation. Lancet ii: 1220—1223 (1970). 7 Hall, C.L.; Pejhan, N.; Thomson, R.W.; DawsonEdwards, P.; Barnes, A.D.; Robinson, B.H.B.; Meynell, M.J.; Blainey, J.D.: Serial estimation of urinary fibrin/ fibrinogen degradation products in kidney transplanta tion. Br. med. J. iii: 204—207 (1973). 8Hedner, U.: Urinary fibrin/fibrinogen degradation prod ucts (FDP) in renal diseases and during thrombolytic therapy. Scand. J. clin. Lab. Invest. 32: 175 — 182 (1973). 9 Hulme, B.; Pitcher, P.M.: Rapid latex-screening test for detection of fibrin/fibrinogen degradation products in urine after renal transplantation. Lancet i: 6—8 (1973).
49
Eur. Urol. 4: 46-49 (1978)
Fibrinolytic Degradation Products in Urine of Anticoagulated Transplant Patients J.J. Aguilo, E.J. W. Bowie, J.E. Woods and C.A. Owen, jr. Mayo Clinic, Mayo Graduate School of Medicine, University of Minnesota, Rochester, Minn.
Abstract. A study of the level of urinary fibrinolytic split products in 14 renal transplant patients who received oral anticoagulants postoperatively revealed a tendency toward increased levels of fibrinolytic split products that were temporally related to graft rejection. The amount of fibrinolytic split products in the urine was positively related to the severity of rejection as well as to the final status of the allograft. Thus, the urinary level of fibrinolytic split products, as determined by the latex-coated particle test, can be used as an indicator of the course of warfarin-anticoagulated patients after renal allografting.
Key Words. Fibrin fibrinogen degradation products Fibrinolysis • Transplantation, homologous ■ Warfarin
fibrinogen split products levels were determined in the urine of renal transplant patients who were effectively anticoagulated. Materials and Methods 14 renal transplant recipients were studied. 9 received a kidney from a living relative and 5 received cadaveric kidneys. All but 1 patient were bilaterally nephrectomized before transplantation. Patients were anticoagulated with subcutaneous heparin (5,000 U every 12 h) from the time of transplant to the end of the 6th postoperative day; 48 h after renal allografting, oral anticoagulation with warfarin was begun. Prothrombin times, obtained daily for all patients, were in the therapeutic range, that is, over 17 sec (controls, 10—11 sec). In 1 patient (case 7), anticoagulation was discontinued after the presence of a perirenal hema toma was suspected. In 11 patients, daily urine samples were obtained; in 3 other patients, urine samples were obtained every other day. The samples of urine were collected, starting on the 7th day after transplantation, when the urine was free of detectable blood. Patients were studied from 9 to 47 days (average, 21 days). 2 ml of fresh urine were placed immedi ately in specially provided 3-ml rubber-plugged glass tubes. The tubes contained thrombin to clot any possible fibrin ogen and soybean trypsin inhibitor to inhibit degradation of fibrin or fibrinogen. After thorough mixing, samples were frozen at —20 C and were thawed just before testing. Urine was tested undiluted, diluted fivefold, and with further serial dilutions. A drop of each dilution was stirred with one drop of previously shaken latex suspension (con taining the antibody) with an applicator stick until the mixture appeared to be homogeneous. The slide was then rocked gently for 2 min and observed against a dark background for evidence of agglutination.
Downloaded by: American University of Beirut - Jafet Library 193.188.128.21 - 6/11/2019 8:10:53 AM
After renal allografting, the rising levels of fi brinogen split products in urine have been used as a method of detecting the rejection phenomenon. It has been thought that after renal transplantation, anticoagulation with warfarin derivatives might de crease the amount of fibrinogen split products in the urine and thus interfere with the reliable detection of rejection by this method. To determine the relationships of anticoagula tion to levels of urinary fibrinogen split products and rejection, we studied 14 anticoagulated pa tients with renal allografts. The rapid latex-screen ing test was used to measure urinary fibrinogen split products levels. Several different methods of measuring fibrinogen split products levels in urine have been devised (3—5, 8, 9), but a practical one is the rapid latex-screening test (1, 9). This is a semiquantitative test and uses antibody-coated latex particles ( 1 ). We have used warfarin as the anticoagulant during the postoperative period after renal allo grafting for the last 3 years. The aim is to prevent embolic phenomena, not to prevent rejection. The use of warfarin anticoagulants as antirejection med ication is doubtful, or at least controversial (2). The present study represents the first in which
Fibrinogen Degradation in Urine of Anticoagulated Renal Transplants
47
Table I. Relationships of levels of fibrinogen split products, rejection, and allograft status in 14 anticoagulated renal transplant patients Case No.
Kidney Maximal donor fibrinogen type split products Mg/ml
Fibrinogen split products increased before rejection (days)
Decreased fibrinogen split products in relation to méthylprednisolone
Type of rejection
Allograft status
Increased sensitivity to warfarin when rejecting
13 9 14
3
LRD LRD LRD LRD CAD CAD CAD
no 2 no no2 no2 no2 no2 no
acute none none none none none chronic
LRD
20—< 40
no
yes
chronic
4
CAD
40—< 80
no
no
acute
5
LRD*1 l LRD
80— 160
yes (1) yes (6)
no no
acute acute
7
LRD
> 160
no rejection
no2
6
CAD
> 160
yes(3)
yes
acute tubular necrosis acute
good good good died3 good good lost at 4 months lost at 30 days lost at 23 days good lost at 40 days good
no
20—< 40 20—< 40 20—< 40 20—< 40 20—< 40
no no rejection no rejection no rejection no rejection no rejection yes (8)
2
1
LRD
> 160
yes (2)
yes
acute
11 10 8
12
l
10-< 20 10-< 20
lost at 30 days lost at 14 days
no yes yes no yes no anti coagulant yes yes
Samples that agglutinated undiluted urine were con sidered to contain fibrinogen split products in a concentra tion of more than 2 pg/ml. Progressively increasing dilu tions were considered to be positive in accordance with this rule. Positive and negative urine specimens were used as controls to be certain of the reliability of the method. 60 samples from 10 healthy adults were tested to establish the normal baseline. 9 of the 10 had a positive test on undiluted urine at one time or another (fibrinogen split products, >2;Ug/ml). 3 of these 9 occasionally exhibited positive results on 1:5 diluted urine (fibrinogen split prod ucts, > 10pg/ml) but none were positive in 1:10 diluted urine.
Results Significant elevation of fibrinogen split products levels in the urine (more than 20 Mg/ml) was seen in 12 of the 14 patients (table I). Of these 12 patients, 6 had fibrinogen split products concentra tions greater than 40 Mg/ml, 5 had higher than 80 Mg/ml, and 4 had higher than 160 Mg/ml.
Of the 2 patients with fibrinogen split products values less than 20 Mg/ml, one (case 13) had a transient episode of rejection without elevation of fibrinogen split products levels that was well con trolled by increased immunosuppressive treatment. The other patient (case 9) never had evidence of rejection. Both patients had normal creatinine levels after transplantation, 1 patient at 6 months and the other at 10 months. Of the 6 patients who had fibrinogen split products levels between 20 and 40 Mg/ml, 4 never had clinically significant rejection. 3 of the 4 continued to have good functioning grafts 9 months to 1 year after transplantation. The 4th patient died of unrelated causes; at the time of death, the serum creatinine level was 2.55 mg/dl. The other 2 patients had chronic rejection and lost their allografts — one 1 month and the other 4 months after transplantation. Of the 6 patients who had fibrinogen split products levels greater than 40 Mg/ml, 5 had acute
Downloaded by: American University of Beirut - Jafet Library 193.188.128.21 - 6/11/2019 8:10:53 AM
LRD = Living related donor; CAD = cadaveric donor. 1 Collected on alternate days. 2 Never received a high dosage. 3 Unrelated causes.
Aguilo/Bowie/Woods/Owen, jr.
48
clinical rejection. One (case 7) had prolonged acute tubular necrosis and received anticoagulants only for the first 15 days after transplantation. Of the 6, only this patient and another patient (case 5) eventually recovered their kidney function; the other 4 lost their allografts 24-30 days after transplantation. 3 of the 4 patients had fibrinogen split products levels greater than 160jUg/mfi and acute rejection occurred without recovery of kid ney function in spite of energetic immunosuppres sive treatment (fig. 1).
Comments Our study revealed that 12 of the 14 patients had elevated urinary fibrinogen split products levels sometime after kidney transplantation (ex cluding the first 2 postoperative weeks) in spite of effective anticoagulation with warfarin. This is in contrast with results of previous reports (5, 6) which report a reduction in fibrinogen split prod ucts levels in the urine. 5 patients without clini cally significant rejection had levels of fibrinogen split products between 20 and 40 ßg/ml. High levels of fibrinogen split products in the urine were
References 1 Arocha-Pinango, C.L.: A comparison of TRCII and latex-particle tests for the titration of FR-antigen. J. clin. Path. 25: 757-761 (1972). 2 Barnes, A.D.; Coles, G.A.; White, H.J.O.: A controlled trial of anticoagulants in cadaveric renal transplantation. Transplantation 11: 491-494 (1974). 3 Bennett, N.M.: Bennett, D.; Holland, N.H.; Luke, R.G.: Serum fibrin degradation products in the diagnosis of transplantation rejection. Transplantation 14: 311—316 (1972). 4Carlsson, S.; Hedner, U.; Nilsson, I.M.: Kidney transplan tation and fibrinolytic split products in serum and urine. Transplantation 10: 366—371 (1970). 5 Cash, J.D.; Clarkson, A.R.: Serum and urinary fibrin/ fibrinogen degradation products in renal disease. Scand. J. Haematol. 13: suppl., pp. 331-336 (1971).
Downloaded by: American University of Beirut - Jafet Library 193.188.128.21 - 6/11/2019 8:10:53 AM
Fig. 1. Case 12. Example of serum creatinine, urinary fibrinogen split products levels, and prothrombin time changes.
positively correlated with rejection and irreversible damage. Whether the donor source was a cadaver or a living relative did not seem to be significant. Of the 6 patients with fibrinogen split products levels greater than 40 jug/ml, 2 had received cadav eric kidneys and 4 had received living related donor kidneys. It has been observed that elevation of the uri nary fibrinogen split products levels frequently occurs several days before the rejection phenome non (6, 7, 9). In our series, elevation of fibrinogen split products levels (> 80 /xg/ml) occurred from 24 h to 6 days before clinical evidence of rejection. Our treatment for rejection includes an increase in the dosage of intravenous méthylprednisolone, with doses as high as 2 g and 500 mg, alternated daily, to a total dosage of 12—15 g, and 450 rad of radiation in three sessions (11). Antilymphocytic globulin is not included in our treatment protocol. High dosages of méthylprednisolone were related to decreases in the fibrinogen split products con centration in the urine in 2 of the patients who had fibrinogen split products levels greater than 160 Mg/ml. Patients with fibrinogen split products levels higher than 40 ßg/ml who had rejected their allo grafts appeared to be especially sensitive to warfa rin, as reflected by sudden prolongation of their prothrombin times to 40—50 sec (cases 1, 2, 4, 6, and 12). Although the reason for this is not known, it has been suggested that, even if there is no evidence of disseminated intravascular coagula tion or systemic fibrinolysis during rejection (3), the damaged renal tubule and arteriolar endo thelium with their well-known fibrinolytic poten tial (4, 10) may contribute to the prolongation of prothrombin times.
Fibrinogen Degradation in Urine of Anticoagulated Renal Transplants
lOWardle, E.N.; Menon, I.S.; Uldall, P.R.; Swinney, J.: Proteins and fibrinolysis in recipients of renal allografts. J. clin. Path. 24: 124-128 (1971). 11 Woods, J.E.; Anderson, C.F.; DeWeerd, J.H.; Johnson, W.J.; Donadio, J.V., jr.; Leary, F.J.; Frohnert, P.P.: High-dosage intravenously administered méthylpredni solone in renal transplantation. A preliminary report. J. Am. med. Ass. 223: 896-899 (1973).
Dr. J.J. Aguilo, Clinica Quiron, Avda. Virgen de Montserrat 5, Barcelona 12 (Spain)
Downloaded by: American University of Beirut - Jafet Library 193.188.128.21 - 6/11/2019 8:10:53 AM
6 Clarkson, A.R.; Morton, J.B.; Cash, J.D.: Urinary fibrin/ fibrinogen degradation products after renal homotrans plantation. Lancet ii: 1220—1223 (1970). 7 Hall, C.L.; Pejhan, N.; Thomson, R.W.; DawsonEdwards, P.; Barnes, A.D.; Robinson, B.H.B.; Meynell, M.J.; Blainey, J.D.: Serial estimation of urinary fibrin/ fibrinogen degradation products in kidney transplanta tion. Br. med. J. iii: 204—207 (1973). 8Hedner, U.: Urinary fibrin/fibrinogen degradation prod ucts (FDP) in renal diseases and during thrombolytic therapy. Scand. J. clin. Lab. Invest. 32: 175 — 182 (1973). 9 Hulme, B.; Pitcher, P.M.: Rapid latex-screening test for detection of fibrin/fibrinogen degradation products in urine after renal transplantation. Lancet i: 6—8 (1973).
49
