ANNALS OF CLINICAL AND LABORATORY SCIENCE, Vol. 8, No. 3 Copyright © 1978, Institute for Clinical Science

The Serial Thrombin Time in the Diagnosis of Consumptive Coagulopathy

KENNETH B. ALONSO, M.D.

Laboratory Procedures® South, A Division of the Upjohn Company, Decatur, GA 30035

ABSTRACT

Acute consumptive coagulopathy may be initiated by diverse events. It is frequently necessary to establish the diagnosis with urgency. Rational therapy can only be approached with knowledge of the relative impact the primary consumption exerts upon hemostasis as well as the effects of sec­ ondary fibrinolysis. A constellation of interlocking tests within the capability of the small laboratory is presented. This includes the prothrombin time, the activated partial thromboplastin time, the serial thrombin time, the heat precipitation fibrinogen level, the platelet count, red cell morphology, the levels of fibrin (fibrinogen) degradation products and selected factor assays. This series can be completed within 45 minutes. Interpretation, with particular emphasis upon the stage in the natural history of the process when evaluation is instituted, and underlying diseases which modify typical patterns are discussed. The discriminant function of the serial thrombin time is stressed.

Introduction products inhibit the coagulant action of Acute consumptive coagulopathy may thrombin and the polymerization of be initiated by diverse events. The syn­ fibrin monomer.13 Furthermore, plas­ drome has been recognized in an ever min degrades factors V1 and VIII.7 As growing number of clinical settings.8 The vessels are occluded with porous clots, clinical and laboratory expression of these anoxia occurs, red cells are hemolyzed initiating processes is similar although not and further activation of the clotting cas­ identical. The primary cycle of consump­ cade and fibrinolytic mechanisms occurs. tion is initiated with the consumption of The cycles tend to be self perpetuating platelets, fibrinogen, factor II, factor V, with massive bleeding and diffuse vessel factor VIII and factor X. The presence of damage resulting.12 fibrin, the release of vasculokinase from The diagnosis of the clean cut case of damaged vessels and perhaps the activa­ acute consumption is not difficult. How­ tion of factor XII,10 all result in the conver­ ever, subtle cases can be difficult to dis­ sion of plasminogen to plasmin with activa­ tinguish from other conditions. The cycle tion of the fibrinolytic cycle. Degradation of consumption or the cycle of fibrinolysis 228 0091-7370/78/0500-0228 $00.90 © Institute for Clinical Science, Inc. SERIAL THROMBIN TIME IN CONSUMPTIVE COAGULOPATHY 2 2 9 may be prominent. Frequently, other ac­ able from sample #1, a heat precipitation quired coagulopathies may be super­ fibrinogen assay was set up.9 The initial imposed (i.e., as in hepatic disorders).4'5 thrombin time14 was then performed on Interpretation of laboratory data may be the plasma from sample #1 and a serial treacherous. The greatest difficulty is the thrombin time begun. The serial throm­ need for rapid diagnosis. That constella­ bin time is a thrombin time performed on tion of interlocking tests which may give plasma samples incubated at 37°C for the largest amount of information in a varying time periods.14 If the initial short time is emphasized. Performed are thrombin time was abnormal, an attempt the prothrombin time, activated partial was made for correction with normal thromboplastin time, thrombin time and plasma and with protamine sulfate. An serial thrombin time. Specific levels of activated partial thromboplastin time and fibrinogen and fibrinogen/fibrin degrada­ a prothrombin time were performed. The tion products are also determined. This fibrinogen was then read. At 30 minutes, manuscript presents the experience ob­ nearly all tests are complete. The rapid tained in 37 patients, hospitalized in a 175 latex test was performed on sample #3 bed suburban general hospital, who were for degradation products and the smears evaluated for significant acute bleeding in were examined. Plasma remained availa­ settings predisposed to acute consump­ ble for selected factor assays. tive episodes. Results and Conclusions M ethod The laboratory results on the 37 pa­ The laboratory procedure involved tients evaluated for significant acute drawing the following samples with a two bleeding are shown in table I. In no in­ syringe technique: stance was an episode of primary fibri­ nolysis uncovered. The diagnosis of 1. Ten ml of whole blood anticoagu­ acute consumptive coagulopathy was lated with 0.1M balanced citrate strongly considered if (1) the prothrom­ were drawn. In the infant, 5 ml may bin time, the activated partial thrombo­ be sufficient although all tests may plastin time and the thrombin time were not be run in duplicate. Blue top prolonged, (2) low levels of platelets and vacuum tubes are permissible sub­ fibrinogen were present, and (3) stitutes. Samples should be col­ fibrinogen/fibrin degradation products lected in ice. could be demonstrated. 2. Five ml of whole blood anticoagu­ Certain results are clear. First, the lated with ethylendiamine-tetra- presence of schistocytes was noted only acetic acid (EDTA) were drawn. in cases diagnosed clinically as an acute Lavender top vacuum tubes are consumptive coagulopathy. In no in­ permissible substitutes. stance other than acute consumptive 3. Two ml of whole blood were drawn coagulopathy were schistocytes seen. in a glass tube containing soy bean Fragmented erythrocytes, though, were trypsin inhibitor (3600 NF units) present in some patients on chemo­ and bovine thrombin (20 NIH therapy. Second, the presence of abnor­ units). mal levels of fibrinogen/fibrin degrada­ Sample #1 was immediately cen­ tion products is associated with an acute trifuged. While sample #1 was being consumptive coagulopathy but is not centrifuged, a phase platelet count and a diagnostic of the same. Conversely, peripheral smear were prepared from equivocal levels of fibrinogen/fibrin de­ sample #2. As soon as plasma was avail­ gradation products may also be as- 2 3 0 ALONSO

T A B L E I

Clinical Cases Examined

PLT I Hct No. Sex D isorder PT APTT TT STT (xlO^) (mg/dl) FDP (v o l/d l) Smear Other

No Evidence of Hepatic or Consumptive Disorders

1 M Aortic valve 1 2 . 8 5 0 .0 1 1 . 0 * 70 150 - 38 11 ATIII 49.2 sec endocarditis 2 F CGL 13.9 45.0 1 3 .9 * 41 130 _ 31 _ I I 92% A T III 2 9 .8 s< 3 M Cirrhosis 17.0 65.2 11.4 * 161 125 - 30 - I I 42% 4 M AV canal 16.8 46.4 17.0 * 43 75 / 42 - I I 26%; V I I I 112% 5 F Fetal death 13.5 41.3 11.3 * 369 150 - 30 - 6 M Sepsis 14.5 50.2 1 3 .8 * 473 158 - 35 - V I I 143% ; IX 45% 7 M AGL 1 4 .9 5 1 .7 1 3 .8 * 9 1 0 0 - 28 - I I 74%; V I I I 250% 8 F Infant 15.7 73.5 14.2 * 250 325 - 37 - IX 10%; I I 26% 9 M Sepsis 14.9 6 6 . 6 1 2 . 2 * 92 2 0 0 + 39 - II 51%; VII 49%; IX

Hepatic but Not Consumptive Disorders

1 0 M I n f a n t 1 2 . 8 6 0 .6 1 7 .8 * 6 150 / 37 - 1 1 M Cirrhosis 28.5 86.3 18.1 * 53 150 - 35 - I I 14%; V I I I 90% 1 2 M C i r r h o s i s 1 4 .0 3 7 .8 9 .7 * 80 1 0 0 - 30 - 13 F Hepatic 16.7 1 1 7 .0 1 4 .0 t 33 1 1 0 - 23 “ I I 28% A T II I 1 4 .2 s< f a i l u r e SBE 14 M Hepatitis 16.5 66.9 1 4 .5 t 36 1 2 0 _ 43 _ I I 41% 15 M C i r r h o s i s 1 5 .2 5 1 .6 1 2 . 0 t 14 160 - 2 0 - I I 6 8 % 16 M Hepatorenal 16.8 104.6 1 3 .8 t 57 190 - 27 - I I 69% A T II I 1 6 .4 Si sy n d ro m e 17 M C i r r h o s i s 17.4 8 2 .2 1 3 .0 + 258 1 1 0 _ 30 - I I 29% 18 F Cirrhosis 18.2 96.1 17.3 t 259 250 - 30 - I I 37%; V 65% 19 F Hepatitis 17.8 60.1 10.3 t 96 240 - 34 - I I 72%; V I I 175% 2 0 M Cirrhosis 15.5 92.8 15.3 t 17 50 - 29 - I I 27% 2 1 M C i r r h o s i s 14.7 46.1 18.5 t 91 1 1 0 - 32 - 2 2 M Cirrhosis 16.0 9 7 .6 1 5 .1 t 332 240 - 29 - II 38%; IX 5% 23 M H e p a t i t i s 3 4 .3 1 2 0 . 0 2 3 .0 t 395 140 - 35 - I I 19%; V I I I 19% 24 M Hepatitis 19.8 72.8 23.0 t 77 150 - 40 - I I 21%

Consumptive Disorders

25 M I n f a n t 2 2 . 6 49.2 18.0 § 358 140 + 44 (0 I I 30% 26 F I n f e c t i o n 1 2 .9 4 8 .9 11.0 § 204 1 2 0 ” 42 Cl) II 97%; V 26%; ATIII 18.8 sec 27 F SLE 1 4 .9 5 3 .5 1 9 .0 § 53 150 + 32 + I I 29% 28 F HUS 1 9 .4 72.2 23.0 § 140 420 + 32 + I I 23% 29 M I n f a n t 4 0 .7 1 2 0 . 0 5 9 .8 § 125 75 + 24 to I I 11% 30 F SLE 2 2 . 0 4 0 .0 1 1 .5 § 85 1 1 0 + 29 co VII 75%; ATIII 15.4 31 M S e p s is 2 6 .3 1 0 2 . 8 2 1 .5 § 42 60 / 35 (1) II 20%; VII 44%; IX 32 F C h o r io ­ 1 2 .5 3 8 .7 1 2 1 § 130 560 / 37 Ü) c a rc in o m a 33 M I n f a n t 1 8 .2 1 2 8 .4 1 9 .4 § 79 90 + 45 co 34 M Infant 18.0 48.2 18.6 § 36 1 1 0 - 28 ID 35 MTTP 17.0 31.1 26.4 § 15 187 + 2 0 to 36 F P o is o n in g 41.3 118.4 50.0 § 186 15 + 44 to 37 F Pneumonia 18.6 42.6 34.6 § 52 188 + 36 CO

PT = Prothrombin Time - normals 12 ± 2 secs. APTT = Activated Partial Thromboplastin Time - normals 35+2 s e c s . TT = Thrombin Time - normals 12 ± 2 secs. STT = Serial Thrombin Time PLT = Platelets I = Fibrinogen FDP = Fibrinogen/Fibrin Degradation Products Hct = Hematocrit ATIII = Serum Antithrombin III - activity normals 52.0 ± 18.0 secs. ♦Linear tNon-linear tail §Non-linear -Negative /Equivocal +Positive coSchistocytes CGL = chronic granulocytic leukemia AV canal = common atrioventricular orifice (canal) AGL = acute granulocytic leukemia SLE = systemic lupus erythematosis SBE = subacute bacterial endocarditis HUS = hemolytic uremic syndrome TTP = thrombotic thrombocytopenic purpura

sociated with an acute consumptive to permit a diagnosis of acute consump­ coagulopathy. This was seen in three pa­ tive coagulopathy to be made with these tients. Third, low levels of platelets, low tests alone. Similarly, selected factor as­ levels of fibrinogen and abnormal pro­ says are limited to the information pro­ thrombin and partial thromboplastin vided. Classically, the acute reactive pro­ times are not sufficiently discriminatory coagulants, factor VIII, fibrinogen, and SERIAL THROMBIN TIME IN CONSUMPTIVE COAGULOPATHY 2 3 1 platelets rebound to supranormal levels screening tests with a linear serial and decay to normal levels in the order thrombin time. listed following an acute initiating event. C ase #7 If the patient is evaluated at a time other A 45 year old white male with acute granulocytic than when all procoagulants are de­ leukemia on combined therapy began to bleed pressed, the laboratory parameters pre­ briskly from the nose and oropharynx. Physical sent a confusing picture. Case #30 shows examination revealed pallor and petechiae. The hematocrit was 28 vol per dl and the leukocyte this difficulty. count was 2500 mm-3. Laboratory data obtained at this time incubated: C a se #30 PT 14.9 sec (12.0 sec control) APTT 51.7 (35.6) A 35 year old Indian (Lakota) female with sys­ TT 13.8 (10.2) temic lupus erythematosus (SLE) was evaluated for STT 0 min 13.8 sec a persistent, refractory anemia. The hematocrit was 15 15.5 29 vol per dl. A reticulocyte count eas 3.2 percent. 30 17.3 Coombs tests were negative. A bone marrow 45 19.1 examination showed mild erythroid hyperplasia and 60 23.7 no overt bleeding was noted. Abnormal coagulation tests values were present. Pits 9,000 I 100 mg per dl Prothrombii time FDP Negative (PT) 22.0 sec (11.6 sec control) II 74 percent Activated partial thromboplastin time VIII 250 percent (APTT) 40.0 sec (34.8 sec control) Smear Negative Thrombin time (TT) 11.5 sec (11.2 sec control) With plasma and platelet transfusions, the bleeding Serial thrombin time ceased and the PT, APTT and TT returned to nor­ (STT) Omin 11.5 sec mal. 15 13.0 30 14.8 The serial thrombin time looks at acute 45 17.7 60 22.5 protolytic and thrombolytic activity.3 In those patients with hepatic disor­ Alpha adrenergic blockade was attempted. Platelets rose to 328,000 mm-3, fibrinogen to 150 mg per dl ders, significant deviation from linearity and fibrinogen/fibrin degradation products were occurs at the later incubation periods as is negative. illustrated in Case 10, an infant felt to manifest intravascular platelet throm­ An abnormal throm bin time is the most bosis. sensitive screening test of abnormal con­ sumption or fibrinolysis in our hands. Case #10 However, it was normal initially in three A 23 year old healthy white female in her first patients with consumption. pregnancy delivered spontaneously a 3.2 kg male infant at term. The infant was taken to the nursery The serial thrombin time is one which for routine care. At one day of age, the infant was effectively discriminates between con­ noted to have numerous ecchymoses and to be sumptive and nonconsumptive states. bleeding from the umbilicus. Laboratory examina­ tion showed: Fourth, three distinct patterns were PT 12.8 sec (12.0 sec control) noted in the serial thrombin time. The APTT 60.6 (35.2) “normal” response as first described with TT 17.8 (11.2) citrated plasma and human thrombin6 STT 0 min 17.8 sec and also seen here with bovine thrombin 15 19.0 30 20.4 is a slight linear increase in thrombin 45 21.5 time with plasma incubation from 0 to 60 60 23.0 minutes. (A constant percentage accelera­ Pits 6,500 tion of the serial thrombin time after 37 0 I 100 mg per dl FDP Equivocal incubation has also been described with HCT 37 mol per dl oxalate as the anticoagulant.2 The curve, Smear Negative however, is not linear). This is shown in Heparin aggravated the bleeding. The infant re­ figure 1. Case #7 contrasts abnormal sponded to Vitamin K. 2 3 2 ALONSO

Fifth, hepatic disorders proved to be On the third day of continued bleeding, the labo­ the most common single organ system ratory examination showed: abnormalities which interfered with in­ PT 20.3 sec (12.0 sec control) terpretation of laboratory data. In the in­ APTT 65.0 (34.5) TT 13.7 (10.2) fant with an immature liver, or the adult Pits 13,000 with parachymal disease, diminished I 125 mg per dl levels of plasminogen as well as pro­ Following heparin therapy the laboratory values coagulants may mask both consumption returned to normal. and fibrinolysis. Conversely, diminished C a se #28 clearing of plasminogen as well as acti­ vated procoagulants (X“) may accentuate An 18 year old healthy white female in her second pregnancy delivered spontaneously a 3.5 kg female the consumptive picture. The thrombin infant at term. No irregular antibodies were found time, then, may be nonspecifically pro­ in prenatal screening of the mother’s blood. The infant did well in the hospital and was discharged to longed. The serial thrombin time enables the mother’s care. At six weeks of age, following a the identification of hepatic interference “flu-like” illness, the infant was anorectic and irrit­ to be made.11 Finally, in those patients able. The urine was dark. The infant was admitted to the neonatal intensive care unit. Generalized with both consumptive and fibrinolytic bleeding was noted. The hematocrit was 32 vol per processes, significant deviation from dl with a leukocyte count of 15,000-3 consisting linearity is noted early in the incubation predominantly of polys. A BUN was 35 mg per dl and Coombs tests were negative. Laboratory period and is illustrated by Cases #32, 28 examination showed: and 30. PT 19.4 sec (11.6 sec control) APTT 72.2 (34.7) C ase #32 TT 23.0 (11.0) A 23 year old white female underwent curettage STT 0 min 23.0 sec during a workup for secondary amenorrhea. The 15 28.0 uterus was perforated during the procedure and a 30 35.0 hysterectomy was performed. Choriocarcinoma was 45 50.0 discovered in the specimen. Mild bleeding was 60 not done noted from venipuncture sites following surgery. Initial laboratory examination showed: Pits 140,000 I 420 mg per dl PT 12.5 sec (11.9 sec control) FDP Positive APTT 38.7 (34.7) Smear Schistocytes TT 12.1 (10.0) STT 0 min 12.1 sec Heparinization was instituted in this clinical set­ 15 14.0 ting and laboratory values returned to normal. 30 17.4 45 21.3 C ase #30 60 25.5 Pits 130,000 Case #30, which was described previ­ I 560 mg per dl FDP Equivocal ously, particularly illustrates the value of HCT 37 vol per dl the serial thrombin time in the evaluation Smear Negative of the chronic consumptive states. In fi­ The patient was then begun on a chemotherapy. brinolysis, the serial thrombin time She continued to bleed on the following day from measures plasmin activity.2 The euglobu- venipuncture sites. The second laboratory examina­ tion showed: lin lysis time looks at plasminogen activa­ tion and may further separate consump­ PT 13.1 sec (12.2 sec control) tive from primary fibrinolytic episodes.3 APTT 46.5 (35.2) TT 13.2 (10.3) In table II are shown the patterns of the STT 0 13.2 sec serial thrombin time. 15 16.5 30 21.0 45 26.7 Conclusion 60 32.0 The addition of the serial thrombin Pits 45,000 I 300 mg per dl time to the rapid screening laboratory FDP Positive procedures employed in settings dis- SERIAL THROMBIN TIME IN CONSUMPTIVE COAGULOPATHY 233

TABLE I I

Serial Thrombin Time* Patterns After Different Periods of Incubation at 37°C

Incubation Time 0 Minutes 15 Minutes 30 Minutes 45 Minutes 60 Minutes

No evidence of hepatic disease 12.5 ± 1.5* 13.6 ± 1.2* 14.8 ± 1.6* 17.0 ± 1.7* 18.0 ± 1.5* or consumptive coagulopathy Hepatic disease 14.3 ± 4.3* 16.5 ± 4.6* 18.8 ± 5.0* 21.2 ± 4.8* 25.4 ± 6.3* Consumptive coagulopathy 18.2 ± 6.0* 21.5 ± 6.8* 25.7 ± 6.8* 31.5 ± 7.0* 38.9 ±10.3*

*Serial thrombin time given in seconds.

posed to acute consumptive coagulop­ 6. Ingram, G. and M a tc h e tt, M.: The ‘serial athy enables the physician to separate thrombin time’ method for measuring fibrino­ lytic activity in plasma. Nature .288:674-675, consumptive episodes and is instrumen­ 1960. tal in making therapeutic decisions. Once 7. L ew is, J., H o u r, A., and F e rg u s o n , J.: the defect is established, however, Thrombin formation II. J. Clin. Invest. 28:1507-1510, 1949. monitoring the levels of the classic pro­ 8. M inna, J. D., Robboy, S. J., and C olm an, R. coagulants may be more useful.2 W.: Disseminated Intravascular Coagulation in Man. Springfield, Charles C Thomas, 1974. 9. M oore, J., Meva, P., Perry, S., G rangerg, References P., Chang, N., and Crooks, W.: The assess­ ment of fibrinogen deficiencies in pregnancy. 1. Alagille, D. and S oulie r, J.: Action des en­ Amer. J. Obst. Gynec. 83:1036-1044, 1962. zymes protrolytiques surle sang total ‘in vitro’. 10. O gston, D., O gston, C., Ratnoff, O., and Sem. Hop. 32:355-359, 1956. Forbes, C.: Studies on a complex mechanism 2. B rodsley, I., Meyer, A., Kahn, B., and Ross, for the activation of plasminogen by kaolin and E.: Laboratory diagnosis of disseminated in- by chloroform. J. Clin. Invest. 48:1786-1801, travascular coagulation. Amer. J. Clin. Path. 1969. 50:211-4, 1968. 11. Reid, W. O.: The relationship of liver insuffi­ 3. B rodsley, I., Ross, E., and Reid, W. O.: The ciency to fibrinolytic hemorrhage as demon­ use of the serial thrombin time in evaluating strated by the serial thrombin time. Metabo­ therapy with epsilon amino caproic acid in lism i2:631-641, 1963. massive thrombolysis and proteolysis. Amer. J. 12. Simpson, J. and S ta lk e r, A.: The concept of Clin. Path. 41:589-96, 1964. DIC. Clin. Hemat. 2:189-198, 1973. 4. DeNichola, P. and Soardi, F.: Fibrinolysis 13. T riantophyllopaulos , D. and T r ia n - in liver diseases. Thromb. Diath. Haemorrh. TOPHYLLOPAULOS, E.: Physiological affects of 2:290-299, 1958. fibrinogen degradation products. Throm. Diath. 5. Fl e t c h e r , A., Biederm an, O., Mo o re, S., Haemorrh. Suppl. 39:175-186, 1970. Alkjaersig, N., and Sherry, S.: Abnormal 14. ZUCK, T.: Modification of the method of Van plasminogen-plasmin system activity in pa­ Kaulla. Handbook of Hemostasis. Denver, tients with hepatic cirrhosis. J. Clin. Invest. Fitzsimmons Army Medical Center, 1973, 43:681-695, 1964. pp. 58-60.