Constitutional Hypofibrinogenemia Associated with Third Trimester Hemorrhage* D

Constitutional Hypofibrinogenemia Associated with Third Trimester Hemorrhage* D. K. McROYAN, M .D.,| C. J. McROYAN, MT(ASCP)SH,t D. Z. KITAY, and P. I. LIU, M.D., Ph.D .|§ Departments of Pathology, t Obstetrics and Gynecology,$ and Medicine,§ University of South Alabama Medical Center, Mobile, AL 36617

ABSTRACT This case of a 31-year-old white woman presenting at 32 weeks gestation with vaginal bleeding supports a possible association between constitu tional hypofibrinogenemia and third trimester hemorrhage. Clot based fibrinogen assays were persistently low for the third trimester (patient: 102 to 155 mg per dl; normal range: 400 to 650 mg per dl) and at follow- up, ten months post-partum (patient: 90 mg per dl; normal range 180 to 436 mg per dl); an immunologic fibrinogen level was comparable. The patient gave an unremarkable bleeding history. Of 11 previously reported pregnancies in five hypofibrinogénémie patients, six terminated in pla cental abruption during the third trimester, two others were complicated by significant post-partum hemorrhage, and one by spontaneous abortion. This case report emphasizes that low functional levels of fibrinogen are potentially disruptive to the integrity of the uteroplacental interface. The pregnant state unmasks and amplifies an otherwise silent to mild hemo static disorder.

Introduction state may often unmask and amplify an otherwise silent to mild hemostatic dis This case and the few others previ order. ously described indicate an association Congenital quantitative and/or quali between congenitally or constitutionally tative disorders of fibrinogen are uncom low functional fibrinogen levels and the mon and can be segregated into four development of a significant third trimes categories: afibrinogenemia, hypofibri ter hemorrhage.15’22,24,27 Furthermore, nogenemia, hypodysfibrinogenemia and these cases suggest that the pregnant dysfibrinogenemia.19-2125 Individuals with congenital afibrinogenemia have no Address reprint requests to Paul I. Liu, M.D., Ph.D., Department of Pathology, University of South fibrinogen demonstrable by clot based or Alabama Medical Center, 2451 Fillingim Street, immunologic assays. These patients man Mobile, AL 36617. ifest a significant hemorrhagic diathesis 52 0091-7370/86/0100-0052 $00.90 © Institute for Clinical Science, Inc. HYPOFIBRINOGENEMIA IN PREGNANCY 53 throughout life. Congenital hypofibrino- lizing laboratory techniques unavailable genemia, however, is usually a silent to to Prichard have lent support to his spec mild hemostatic defect which may defy ulation that hemostatic measurements on detection unless specifically sought; peripheral blood may not accurately affected individuals have low fibrinogen reflect the environment at the uteropla levels, usually below 100 mg per dl, cental interface.7,1014 This case report which are similar if measured by clot assimilates some of the pertinent obser based or immunologic assays. Congenital vations in this vein. hypofibrinogenemia may represent a dis tinct autosomal dominant entity or the heterozygous state of congenital afibrino Case Report genemia, a variably penetrant autoso A 31-year-old white gravida II, ab I at 32 weeks mal recessive disorder.19 Individuals gestation was admitted for evaluation of third-trimes with congenital hypodysfibrinogenemia ter bleeding. The bleeding was initially associated or dysfibrinogenemia may manifest hem with mild abdominal pain. Subsequently, irregular uterine contractions were maintained and a diagnosis orrhage, thrombosis, or paradoxically of threatened premature labor and possible abruptio both; the diagnosis is suggested by incon placenta was made. The cervix was closed, 70 percent gruence between clot based and immu effaced with the fetus in vertex presentation and floating. Ultrasound showed a fundal placenta with nologic fibrinogen assays and confirmed no evidence of abruption. Vaginal bleeding and uter by more sophisticated and specific tech- ine contractions ceased without hemotherapy within niques. 24 hours. Liver function studies were normal. Coag ulation studies revealed hypofibrinogenemia and are The unmasking of hypofibrinogenemia detailed in table I. Diagnosis of marginal sinus sep during pregnancy and its contribution to aration was made by exclusion. the genesis of gestational hemorrhaging A urinary tract infection was treated with ampicil- lin, and the patient was discharged on the fourth hos may be related to the hemostatic milieu pital day. She had an uneventful vaginal delivery at present at the uteroplacental interface. term. Ten month post-partum her fibrinogen was 90 This hypothesis was proposed by Pri mg per dl. The patient’s past medical history was negative chard in 1961 as a possible cause of except for a single spontaneous abortion. Her men chronic abruption in his hypofibrinogé strual history was unremarkable; there was no per némie patient.24 Since then, studies uti sonal or family history of a bleeding diathesis. TABLE I

Representative Coagulation Studies

Test Normal Range 12/18-22/82 10/13/83

Platelet counts 140 - 440 x 1 0 V 380 Bleeding time 4 - 7 minutes 6 Prothrombin time 9.4 - 12.2 seconds 10.2 Activated partial thromboplastin time 24.0 - 35.0 seconds 30.5 Thombin time Control, 5 seconds 6 Quantitative-functional fibrinogen 400 - 650 mg/dl+ 138 90 (nl 180 - 463) Quantitative-immunologic plasma fibrinogen 400 - 650 mg/dl+ 166 Fibrin degradation products < 10 ug/ml <10 Antithrombin III 78 - 122% Activity/ml 110 Euglobulin lysis time > 60 minutes >60 Plasminogen 2.1 - 4.5 CTA U/ml 4.8 Plasmin 0 CTA CTA U/ml 0 Alpha-2 antiplasmin 75 - 119% Activity/ml 70 Urea solubility test > 24 hours >24

*Normal non-pregnant ranges, normal ranges in pregnancy not definitively established, reference 8; + normal range for third trimester, reference 9; CTA U: Committee on Thrombolytic Activity Units, reference 15. 54 McROYAN, McROYAN, KITAY, AND LIU Materials and Methods The euglobulin lysis time (ELT) was determined17 using the Data-Fi Euglob All laboratory testing was performed in ulin Lysis Test Kit. ® Plasma levels of plas the University of South Alabama Clinical minogen (PGEN), plasmin, alpha-2 anti- Laboratory utilizing standard published plasmin (A2AP), and antithrombin III methodologies. Blood for coagulation (AT-III) were measured13 on a Protopath testing was collected into vacutainer Fluorometerff using fluorogen tagged tubes containing 3.2 percent sodium synthetic substrates in a proteolytic citrate in a ratio of 9:1; blood for hema enzyme detection system, tt tological evaluation was collected simi larly into disodium ethylenediamine tetraacetic acid (EDTA) at a concentra Results tion of one mg per ml of blood. Platelet poor plasma for coagulation studies was Review of the coagulation studies obtained by centrifugation at 1,500 x g reveals that the patient manifested a for 10 minutes. Complete blood counts markedly decreased plasma level of clot- (CBC) and platelet counts (PLT) were table fibrinogen for the third trimester generated on a Coulter Model S-plus II. * despite normal levels of fibrin(ogen) deg The bleeding time (TBT)18 was measured radation products.10 Additionally, the using a Simplate II device, f Prothrom level of antithrombin III was normal fur bin time (PT) and activated partial ther discounting the possibility of dis thromboplastin time (APIT) were per seminated intravascular coagulopathy.7 formed on a Coagamate X-2.t The The normal platelet count and bleeding thrombin time (TT) was generated by time discount quantitative or qualitative visual inspection of end-point using platelet dysfunction. The normal euglob human thrombin.$ The urea solubility ulin lysis time, plasminogen, plasmin, test (UST), a qualitative test for factor and alpha-2-antiplasmin levels for preg XIII, was performed using 5M urea. nancy discount a disorder of systemic Quantitative-functional fibrinogen fibrinolysis.7 The normal urea solubility (FIB-CB) determinations were per test, a screen for Factor XIII deficiency, formed on a fibrometer§ using a Data- discounts this defect and dysfibrinoge- Fi Fibrinogen Determination Kit11 by nemias with a stabilization defect.19 The the method of Okuno et al.23 Quanti- normal thrombin time discounts dysfi- tative-immunologic plasma fibrinogen brinogenemias with a proteolytic phase (FIB-I) was determined^ using a radial defect. The comparability of the clot- immunodiffusion technique with a M- based and immunologic fibrinogen assays Partigen Fibrinogen Kit. 11 Fibrinogen/ is compatible with hypofibrinogenemia, Fibrin degradation products (FDP) were but it does not totally exclude the enumerated by the Thrombo-Wellco- possibility of a hypodysfibrinogene- test,** a semi-quantitative latex aggluti m ja 11,19,21,25 nation test using anti-FDP globulin. Discussion * Coulter Electronics, Inc., Hialeah, FL. t General Diagnostics, Morris Plains, NJ. This patient’s persistently low circulat ± Fibrindex-Ortho, Ortho Diagnostics, Inc., Rar itan, NJ. ing level of fibrinogen for the third § Becton, Dickinson and Co., Rutherford, NJ. trimester and a decreased level at follow- * Dade Diagnostics, Inc., Agunda, PR. up, ten months post-partum, confirm a 11 Calbiochem-Behring, La Jolla, CA. ** Welcome Reagents Ltd., Beckenham, En gland. tt American Dade, Inc., Miami, FL. HYPOFIBRINOGENEMIA IN PREGNANCY 55 hypofibrinogenemic state. The absence This effect becomes most pronounced of a remarkable family history and the during the third trimester. These find unavailability of family members for test ings have been interpreted as demon ing do not allow diagnosis of a congenital strative of impaired fibrinolysis during deficiency although it is believed this is pregnancy. The explanation for this likely. The normality of other laboratory apparent paradox has been the finding of testing and clinical observations suggest decreased circulating plasminogen acti a constitutional deficiency and not an vators and an increased level of inhibi acquired or transient lesion, e.g., dis tors.1,8,16 However, the euglobulin lysis seminated intravascular coagulation time is not specific and reflects primarily (DIC), liver disease, etc. The similarity activator activity as the euglogulin frac of a clot based and immunologic fibrin tion lacks plasmin inhibitors. Further, ogen assay suggest hypofibrinogene- there is evidence of sequestration of acti mia rather than hypodysfibrinogene- vator activity as parturition is accompa mia.11,19,21,25 However, because of the nied by sharp increases in plasminogen lack of more sophisticated investigatory activator levels which Bonnar attributed techniques in our laboratory, our data do to loss of inhibition mediated by the pla not allow us to exclude totally the pos centa.10 The euglobulin lysis time returns sibility of hypodysfibrinogenemia. 1921>25 to normal non-pregnant levels shortly In any event, it is the fibrinogenopenic after parturition.9,20 state that is the focus of this report. Fur Fletcher et al14 assaying soluble fibrin thermore, the patient’s mild bleeding monomer complexes, a measurement of history, previous spontaneous abortion, fibrin formation, fibrin(ogen)olysis and, normal menstrual history, and third therefore, fibrinogen turnover, have trimester hemorrhage are compatible shown that (1) fibrin formation rates with previous reports of congenital hypo- steadily increase fivefold by late preg fibrinogenemia and hypodysfibrinogene nancy over control values, and (2) this mia in pregnancy.15,22,24,27 correlates significantly with the progres On the basis of studies of peripheral sive increase in fibrinogen throughout blood, pregnancy has been characterized pregnancy. This progressive increase in as a “hypercoagulable” state. The levels soluble fibrin monomer complex forma of most coagulation factors increase: tion has been confirmed.6 Further, the fibrinogen, plasminogen, and factors II, level of factor XIII, fibrin stabilizing fac VII, VIII, IX, and X increase, while fac tor, falls steadily during late pregnancy, tors XI, XIII, plasminogen activators, supporting these observations.12 Fletcher and antithrombin III decrease.5,7,10 presumed that this progressive fibrino However, there is a mounting body of gen requirement involves the uteropla evidence that these peripherally based cental circulation and noted that the his measurements may not accurately reflect tologic paucity of fibrin deposition in the the hemostatic milieu at the uteroplacen term placenta supports the concept of tal interface. local fibrinogen consumption and turn The plasma fibrinogen level begins to over. rise in the first month and by late in the The data available on the uteroplacen third trimester normally reaches a level tal unit support the concept of normal of 400 to 650 mg per dl.10,14 This increase pregnancy as a progressive state of in fibrinogen is accompanied by a parallel increasingly compensated consumptive increase in plasminogen, but a decreased coagulopathy.5 The concentration of level of plasma fibrinolytic activity as fibrinogen is lower in placental and uter measured by the euglobulin lysis time.4,8 ine venular bloods compared to periph 56 McROYAN, McROYAN, KITAY, AND LIU eral blood during pregnancy.4,7 Further TABLE II more, the euglobulin lysis time in Reported Complications During Pregnancy pregnant patients has been found to be shorter in ovarian blood than in periph P a tie n t/ eral blood.4 This may be attributable to Study Pregnancy Complication elevated plasminogen activator levels in Prichard,24 1/1 3rd trimester, abruption 1961 n 32nd week , abruption the myometrium which increase in toto /3 31st week , abruption by a factor of ten in late pregnancy over /4 14th week , spontane ous abortion the non-pregnant state.3,28 However, the /5 None Hasselback et al,15 2/1 Post-partum hemorrhage plasminogen activator content of the 1963 3/1 32nd week , abruption term uterus is very low and, perhaps, is Ness et al, 22 4/1 28th week , abruption 1983 /2 30th week , abruption related to consumption by attachment to Strickland et al,27 5/1 Post-partum hemorrhage 1982 fibrin at the time of parturition.14,28 McRoyan et al, 6/1 1st trimester, spontane Trophoblastic tissue contains a larger ous abortion concentration of tissue thromboplastin /2 32nd week, marginal than any other tissue in the mammalian sinus hemorrhage organism.10,26 Also, the placenta lacks plasminogen activators and is rich in plasminogen activator inhibitors.2,7,26,29 ma fibrinogen concentration normally in The observations that plasma plasmino creases from a mean of approximately gen activator levels increase sharply after 300 mg per dl in the non-pregnancy state delivery of the placenta and that systemic to approximately 500 mg per dl in the fibrinolytic activity returns to normal third trimester or an approximate 60 to suggest that inhibition of fibrinolysis is 70 percent increase. Our patient’s non mediated directly or indirectly through pregnant baseline was 90 mg per dl and, the placenta. Taken together, the obser during the third trimester, varied from vations suggest a formidable antagonism 102 to 155 mg per dl. Although this between the plasminogen activator rich reflects an approximately proportionate uterus and the tissue thromboplastin, normal increase in fibrinogen, it is far plasminogen activator inhibitor rich pla below the normal mean for pregnancy centa. , and probably below the level required Of 11 documented pregnancies in five for uteroplacental hemostasis. hypofibrinogénémie patients, six preg Bleeding in these hypofibrinogénémie nancies have been complicated by abrup patients may be attributable to a critical tion in the third trimester, two others by dysequilibrium at the uteroplacental significant post-partum hemorrhage, and interface favoring placental fibrinolysis. one by a spontaneous abortion (table II). It is contended by us that it is this critical This rate is far in excess of the rate of dysequilibrium that has precipitated the complications in the general obstetric abruptions reported in these patients and population. Furthermore, the present the marginal sinus hemorrhage noted in patient experienced a less serious but our patient. This effect may be respon analogous lesion, a marginal sinus hem sible for unmasking this otherwise silent orrhage, at 32 weeks gestation, and a to mild hemostatic defect during preg spontaneous abortion in her previous nancy. Furthermore, Prichard’s original pregnancy. It is believed these bleeding speculation that the chronic abruptions complications reflect an inability to com in his hypofibrinogénémie patient might pensate for increased fibrinogen require be related to hemostatic requirements ments with adequate production at times not reflected in peripheral blood mea of increasing fibrin turnover. The plas- surements now seems quite reasonable. HYPOFIBRINOGENEMIA IN PREGNANCY 57

15. H a s s e l b a c k , R ., M a r io n , R . B ., and T h o m a s , References J. W. : Congenital hypofibrinogenemia in five members ofafamily. Canad. Med. Assoc. 88:19- 1. A s t e d t , B.: On fibrinolysis A. in pregnancy, 22, 1963. labour, puerperium and during treatment with 16. H e l l g r e n , M., and B l o m b a c k , M.: Studies on sex hormones. Acta Obstet. Gynec. Scand. blood coagulation and fibrinolysis in pregnancy, Suppl. 18:1—45, 1972. during delivery and in the puerperium. I. Nor 2. A s t e d t , B ., L e c a n d e r , I., B r o d in , T., L u n d b l a d , mal condition. Gynecol. Obstet. Invet. 12:141- A., and L o w , K.: Purification of a specific placen 154, 1981. tal plasminogen activator inhibitor by mono 17. K o w a l s k i, E., K o p e c , M., and N ie w a r o w s k i, S.: clonal antibody and its complex formation with Evaluation of euglobulin method for the detec plasminogen activator. Thromb. Haemost. tion of fibrinolysis. J. Clin. Path. 12:215-217, 53:122-125, 1985. 1959. 3. A s t r u p , T., B e l l e r , F. K., G l a s, P., and R a s m u s 18. K u m a r, R ., A n s e ll, J. E.,Canoss, R. L. ,a n d D E Y - s e n , J.: Fibrinolytic activity of the human uterine ki n, D. : Clinical trial of a new bleeding time tube. Obstet. Gynec. 25:853-857, 1965. device. Am. J. Clin. Path. 70:642-645, 1978. 4. B e l l e r , F. K., D o u g l a s , G. W., M o r r is , R. H., 19. M a m m e n ,E . F.: Fibrinogen abnormalities. Semin. and J o h n s o n , A. J.: The fibrinolytic system in Thromb. Hemostas. 9:2—72, 1983. pregnancy. Am. J. Obstet. Gynec. 101:587—542, 20. M a n n in g , F. A., W o d z ic k i, A., D u n b a r , L., and 1968. C o o p l a n d , A. T.: The fibrinolytic system in late 5. B e l l e r , F. K., and U s z y n sk i, M.: Disseminated pregnancy, labor, and the early puerperium. intravascular coagulation in pregnancy. Clin. Am. J. Obstet. Gynec. 110:900-907, 1971. Obstet. Gynecol. 17:250-278, 1974. 21. M c D o n a g h , R . P., C a r r e l l , N. A., R o b e r t s , 6. B e l l e r , F. K., E b e r t , C., and D a m e , W. R.: High H. R ., B l a t t , P. M ., and M c D o n a u g h , J.: molecular fibrin derivatives in pre-elamptic and Fibrinogen Chapel Hill: Hypofibrinogenemia eclamptic patients. Europ. J. Obstet. Gynec. with a tertiary polymerization defect. Am. J. Reprod. Biol. 9:105-110, 1979. Hematol. 9:23-38, 1980. B e l l e r , E b e r t , 7. F. K., and C.: The coagulation 22. N e s s , P. M., B u d z y n s k i, A. Z., O l e x a , S. A., and and fibrinolytic enzyme system in pregnancy and R o d v ie n , R . : Congenital hypofibrinogenemia in the puerperium. Europ. J. Obstet. Gynec. and recurrent placental abruption. Obstet. Reprod. Biol. 13:177-197, 1983. Gynecol. 61:519-523, 1983. 8. B o n n a r , J., M c N ic o l , G. P., a n d D o u g l a s , N . S.: 23. O k u n o , T., and S e l e n d o , V.: Plasma fibrinogen Fibrinolytic enzyme s y s te m and pregnancy. B rit. determination by automated thrombin time. M e d . J. 3:387-389, 1969. Am. J. Med. Technol. 38:196-201, 1972. 9. B o n n a r , J., M c N ic h o l , G. P., and D o u g l a s , A. S.: Coagulation and fibrinolytic mechanisms 24. P r ic h a r d , J. A. : Chronic hypofibrinogenemia and during and after normal childbirth. Brit. Med. frequent placental abruption. Obstet. Gynecol. J. 2:200-203, 1970. 18:146-151, 1961. 10. B o n n a r , F.: Haemostasis and coagulation disorders 25. R a t n o f f , O. D., and F o r m a n , W. B .: Criteria for in pregnancy. Bloom, A. L., and Thomas, D. P., the differentiation of dysfibrinogénémie states. eds. Haemostasis and Thrombosis. Edinburgh, Semin. Hematol. 13:141—157, 1976. Churchill Livingstone, 1981, pp. 454-471. 26. S c h n e id e r , C. L. : The active principle of placen 11. C a l b io c h e m -B e h r in c : M-Partigen Fibrinogen Kit, tal toxin: Thromboplastin; its activator in blood. Document Number 1B2208, La Jolla, CA, 1983. Am. J. Physiol. 149:123-129, 1947. 12. C o o p l a n d , A ., A l k ja e r s ig , N., and F l e t c h e r , A .: 27. S t r ic k l a n d , D. M., G a l e y , W. T., a n d H a u t h , Reduction of plasma factor XIII (fibrin stabilizing J. C. : Hypofibrinogenemia as a cause of delayed factor) concentration during pregnancy. J. Lab. postpartum hemorrhage. Am. J. Obstet. G y n e Clin. Med. 75:144-153, 1969. col. 243:230-231, 1982. 13. F a r e e d , J., M e s s m o r e , H. L., W a l e n g a , J. M ., 28. U szy n sk i, M., andU szy nsk a -F o l e je w s k a , R .:The and B e r m e s , E. W.: Diagnostic efficiency of plasminogen activator content of the myome newer synthetic-substrate methods for assessing trium in non-pregnant, pregnant, and parturient coagulation variables: A critical overview. Clin. women. Am. J. Obstet. Gynec. 98:825—831, Chem. 29:225-236, 1983. 1967. 14. F l e t c h e r , A . P., A l k ja e r s ig , N. K.,andBuRSTEiN, 29. U szy n sk i, M., and U szy nsk a -F o l e je w s k a , R .: Plas R.: The influence of pregnancy upon blood coag minogen activator and urokinase inhibitor in ulation and plasma fibrinolytic enzyme function. myometrium, placenta, and amniotic fluid. Am. Am. J. Obstet. Gynecol. 134:743- 751, 1979. J. Obstet. Gynec. 105:1041-1043, 1968.