Search

Background: Disseminated intravascular coagulation (DIC) is a life-threatening complication of septic shock; however, risk factors for its development after admission are unknown. Thromboelastography (TEG) can reflect coagulation disturbances in early non-overt DIC that are not detected by standard coagulation tests. This study investigated the risk factors including TEG findings as early predictors for DIC development after admission in septic shock patients with non-overt DIC., Methods: This retrospective observation study included 295 consecutive septic shock patients with non-overt DIC at admission between January 2016 and December 2019. DIC was defined as an International Society on Thrombosis and Hemostasis (ISTH) score ≥ 5. The primary outcome was non-overt DIC at admission that met the ISTH DIC criteria within 3 days after admission., Results: Of the 295 patients with non-overt DIC, 89 (30.2%) developed DIC after admission. The DIC group showed a higher ISTH score and 28-day mortality rate than the non-DIC group (2 vs. 3, P < 0.001; 13.6% vs. 27.0%, P = 0.008, respectively). The DIC rate increased with the ISTH score (7.7%, 13.3%, 15.8%, 36.5%, and 61.4% for scores of 0, 1, 2, 3, and 4, respectively). Among TEG values, the maximum amplitude (MA) was higher in the non-DIC group (P < 0.001). On multivariate analysis, an MA < 64 mm was independently associated with DIC development (odds ratio, 2.311; 95% confidence interval, 1.298-4.115)., Conclusions: DIC more often developed among those with admission ISTH scores ≥ 3 and was associated with higher mortality rates. An MA < 64 mm was independently associated with DIC development in septic shock patients., Competing Interests: The authors report no funding and conflicts of interest., (Copyright © 2021 by the Shock Society.)

Gastric cancer during pregnancy is extremely rare and difficult to diagnose at early stages because of its nature. Furthermore, it is often difficult to determine the appropriate treatment strategy considering both the patient's condition and the effect of the treatment on the fetus. We present a case of a 34-year-old woman with gastric cancer who was 22 weeks pregnant and had multiple liver and bone metastases at the time of diagnosis. The disease progressed to disseminated carcinomatosis of the bone marrow, in which cancer invades and spreads diffusely to the bone marrow and then presents disseminated intravascular coagulation. Fortunately, the selected systematic chemotherapy dramatically reduced the severity of the patient's cancer and she could deliver her baby successfully. There are few reports of disseminated carcinomatosis of the bone marrow from gastric cancer during pregnancy. Even in such an oncological emergency, prompt chemotherapy saved the mother's life and enabled safe delivery of the fetus.

A 39-year-old male developed bilateral periorbital oedema and tense orbits in keeping with orbital compartment syndrome (OCS) shortly after presenting to the emergency department for uncontrollable epistaxis. Bilateral lateral canthotomy and inferior cantholysis was performed within 30 minutes of onset, with the left side further decompressed via superior cantholysis. Computed tomography demonstrated bilateral proptosis and optic nerve stretch, but no intraorbital haemorrhage or haematoma. Laboratory findings were consistent with disseminated intravascular coagulation (DIC) and sepsis of unknown origin. The right visual acuity recovered to 6/6 -2 from counting fingers, but the left eye failed to improve beyond light perception. This unique case of OCS is the first associated with DIC which had no evidence of intraorbital haemorrhage.

Multidrug-resistant Streptococcus pneumoniae strains were isolated from blood and sputum of a patient with disseminated intravascular coagulation in Sapporo city, Japan. These antibiograms were only susceptible to vancomycin, linezolid, daptomycin, some carbapenems, and some fluoroquinolones. Identical antibiograms, serotypes (19F), and sequence types (ST10017) suggested a shared origin of these isolates. Only one ST10017 strain has been isolated in the same city in Japan previously (2014), and the 2014 isolate is still susceptible to macrolides. The whole genome of the blood-derived isolate was sequenced. The strain harbored resistance mutations in parC, gyrA, pbp1a, pbp2a, pbp2b, and pbp2x, and harbored the resistance genes, ermB and tetM. The nucleotide sequences of parC and pbp2x genes of strain MDRSPN001 were clearly different from those of other S. pneumoniae strains and were similar to those of oral streptococci strains. These findings suggest that strain MDRSPN001 has been rapidly and drastically evolving multidrug resistance by gene replacement and accumulation of genes originating from other strains, such as oral streptococci, Streptococcus mitis., (Copyright © 2018 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Disseminated intravascular coagulation (DIC) is a commonly encountered clinical situation characterized by thrombotic occlusion or bleeding in patients with lung cancer. DIC in patients with cancer is usually asymptomatic, taking a chronic form as a compensatory mechanism. Although acute DIC in patients with lung cancer is rarely reported, it can be fatal. We herein describe a patient with lung adenocarcinoma with an activating mutation of the epidermal growth factor receptor (EGFR) gene who developed acute DIC after minor surgical excision. The patient's condition dramatically improved immediately after administration of erlotinib. This report alerts physicians to the occurrence of acute DIC and serves as a reference in treating EGFR mutation-positive lung cancer in patients with DIC.

Uterine artery embolization (UAE) is typically not indicated in the pre-operative management of pregnancies with a live fetus, because risk of fetal death from reduced uteroplacental blood flow. However, pre-operative UAE in pregnancies with a fetal demise poses no fetal risk, and may offer maternal benefits. Patients with placental abruption resulting in fetal demise are at high-risk for developing disseminated intravascular coagulation (DIC), which could have devastating complications such as peri-operative hemorrhage and death. This case report describes the first successful execution of a pre-operative UAE that effectively prevented antepartum and postpartum hemorrhage in a patient with DIC secondary to a placental abruption and recent fetal demise.

Background: Disseminated intravascular coagulation (DIC) describes a pathologic activation of coagulation mechanisms, leading to thrombi in various organs with contribution to multiple organ failure. In clinical practice, diagnosis of DIC can often be made by laboratory values, including prolonged coagulation times, thrombocytopenia, or high levels of fibrin degradation products. DIC is frequently observed after neurotrauma, but rarely occurs in patients with primary brain tumors. There are only few case reports of DIC in patients with primary brain tumors, all sharing the highly elevated mortality. We report the case of a young patient presenting with secondary glioblastoma, who developed multiorgan failure induced by DIC after extensive intraoperative bleeding., Case Description: A 30-year-old patient was admitted in poor general condition with insomnia, severe headache, and vomiting. She had undergone surgery for secondary glioblastoma twice. Magnetic resonance imaging revealed a left temporoparietal mass lesion with indication for resection. Surgery then was complicated by diffuse intraoperative bleeding due to a high content of microvascular proliferation as shown in the histopathologic workup. Subsequently, an uncontrollable multiorgan failure developed, causing the patient's death 4 days after surgery., Conclusions: Although a rare complication, excessive intraoperative bleeding, especially in surgery for brain tumors located next to the ventricular system, DIC should be kept in mind as a possible diagnosis., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Amniotic fluid embolism is a rare and diagnostically challenging obstetric disease of high mortality rate. We present a case of a 33-year old parturient after vaginal birth, who presented with severe hemorrhagic shock with low platelet count and coagulopathy resistant to treatment with plasma, platelets and coagulation factors and despite of surgical management of bleeding. Laboratory findings revealed consumptive coagulopathy. Other symptoms included dyspnea and atelectatic changes on chest x-ray, together with augmentation of the heart with no proof of ventricular insufficiency in echocardiographic examination. The suspected reason of these alterations was amniotic fluid embolism. The patient survived and came back to her usual activity after 22 days of treatment.

Chronic disseminated intravascular coagulation (DIC) is a rare but life-threatening complication of dissecting aortic aneurysm. Although anticoagulant therapy may often proves effective for controlling DIC itself, patients would have to be hospitalized for a long period due to continuous infusion therapy. Subcutaneous injection of a highly concentrated preparation of heparin calcium may offer one alternative treatment for DIC; however, daily subcutaneous use of heparin for the treatment of DIC has impaired quality of life (QOL). The other alternative therapy is intravenous administration of recombinant human soluble thrombomodulin (rTM), which includes the active extracellular domain of thrombomodulin. Reportedly, rTM effectively resolves DIC by only 6 consecutive days of administration; however, how frequently rTM should be administered after the resolution of chronic DIC to have good control of it has been unclear. We report herein a case of chronic DIC complicated with dissecting aortic aneurysm, whose resolution of chronic DIC achieved by 6 consecutive days of rTM has been maintained by once a week administration of rTM on an outpatient basis.

A 2-month-old girl presented with cervical hemangioma associated with Kasabach-Merritt syndrome. The patient had previously undergone systemic administration of corticosteroids (prednisolone 2 mg/kg/day) and radiotherapy (0.5 Gy × 5 times), which temporarily increased the platelet count, but the effects were short-lived and thrombocytopenia gradually worsened again despite increased dosage of prednisolone to 5 mg/kg/day. Computed tomography and magnetic resonance imaging revealed a hemangioma in the left retroauricular-cervical region with a well-enhanced, ill-defined margin and bony structure involvement. Diagnostic and therapeutic angiography were carried out through the femoral route under general anesthesia. Polyvinyl alcohol particles (250-350 µm) suspended in contrast medium were slowly injected and a fibered coil was finally placed in the proximal portion of the arterial feeder. Angiography after embolization revealed a marked reduction in the tumor stain. Platelet count rapidly increased and reached the normal range on postembolization day 7. Tumor tension decreased on the day after the procedure and tumor size gradually decreased. The patient was discharged with oral corticosteroid therapy at 6 months postembolization. Corticosteroid dose was gradually decreased and coagulation parameters were normal at 1 year postembolization.

Study Objectives: To analyze the accuracy of esophageal endoscopic ultrasound (EUS) with real-time, guided fine-needle aspiration (EUS-FNA) with an on-site cytopathologist in patients with (presumed) lung cancer presenting with mediastinal lymphadenopathy (ML) or a suspect left adrenal gland (LAG)., Design: A single-center prospective study., Patients: Sixty-seven outpatients with (presumed) lung cancer with ML or a suspect LAG on either CT and/or positron emission tomography with 18F-fluorodeoxyglucose (FDG-PET) scan., Interventions: All patients underwent EUS-FNA under conscious sedation. A cytopathologist was present during all procedures., Measurements: EUS with and without fine-needle aspiration (FNA) as compared to FDG-PET was evaluated for accuracy in diagnosing cancer, safety, and rate of avoidance for further surgery., Results: Of 67 consecutive patients (56 men; median age, 64 years), malignant ML or LAG were found in 47 patients (70.1%). In 20 patients (29.9%) without EUS-FNA proof of malignancy, confirmation was obtained by surgical procedure in 13 patients (sarcoidosis [n = 5], infection [n = 1], lung cancer [n = 7]) or by clinical follow-up in 5 patients suggesting benign disease. Sixty-five patients were included in the calculation of test characteristics. With malignancy as an end point, the accuracy for EUS-FNA was 100%. This was better than EUS without FNA (accuracy, 75.4%; p < 0.001) or FDG-PET (accuracy, 75.0% [n = 28]; p = 0.0011). When using final histopathologic diagnosis as an end point, the accuracy of EUS-FNA was 92.3%, since EUS-FNA was unable to show noncaseating granulomas in those patients with sarcoidosis diagnosed after mediastinoscopy. Related to the presence of the in situ cytopathologist, there were no inconclusive samples. No adverse events were recorded, and 67.7% of surgical interventions were avoided following EUS-FNA., Conclusions: The accuracy in this series of EUS-FNA with cytopathologist-assisted rapid on-site evaluation is high. The technique is safe and greatly reduces the number of surgical interventions.

Chronic disseminated intravascular coagulation (DIC) is a well-known complication of aortic aneurysm. A 63-year-old man with bleeding tendency and a large palpable abdominal aortic aneurysm (AAA) was diagnosed as having fibrinolysis dominant DIC by the excessive activation of both coagulation and fibrinolysis (plasmin -alpha2 plasmin inhibitor complex concentration is usually >4 microg/ml). Although several treatments were tried, DIC could not be controlled until the patient was given combined therapy of danaparoid (1,250 U/12 h, bolus IV) and tranexamic acid (0.5 g x 3/day, oral administration). This therapy may be beneficial when control for bleeding is required without restricting the ambulatory movement of patients by continuous drip.

Disseminated intravascular coagulation (DIC) is an acquired coagulation disorder that occurs when the normal hemostatic balance is disturbed, primarily by excessive thrombin formation. Moreover, while DIC is a rare complication of aortic dissecting aneurysm, it is also a well-recognized one. We reported a case of DIC associated with aortic dissecting aneurysm in a 55-year-old woman who was transferred from another hospital because of chest pain radiating to her back and thrombocytopenia. Laboratory findings showed DIC with severe thrombocytopenia, and she was diagnosed as having an acute aortic dissection and DIC. After medical treatment on the aortic dissecting aneurysm, her DIC profile recovered.

This report describes a case of severe coagulopathy and bleeding related to the intraoperative use of topically applied thrombin. Commercial thrombin preparations contaminated with bovine factor V have been shown to stimulate the production of antibodies directed against factor V. These antibodies can cause coagulopathy. Our patient developed antibodies against factor V after intraoperative exposure to topical thrombin. The resulting antibody-mediated depletion of factor V caused a severe and refractory coagulopathy. Vascular surgeons should be aware that the use of topical bovine thrombin can cause severe coagulopathy.

A 54-year-old man was diagnosed as having pancreatic cancer and disseminated intravascular coagulation. His plasma tissue factor level on the 11th hospital day was 996 pg/ml (normal range, 120-270 pg/ml). He was treated with gabexate mesilate, antithrombin III, and low-molecular-weight heparin. However, he died of multiple organ failure on the 17th hospital day. The histological finding was poorly differentiated ductal adenocarcinoma of the pancreas, and the production of tissue factor in this lesion was revealed. Tissue factor is a factor that initiates blood coagulation; thus, its expression in pancreatic cancer is one of the causes of coagulation abnormalities in this disease. Although one report has demonstrated immunoreactivity for tissue factor in pancreatic cancer, the patient's detailed clinical course was not mentioned in that report. This is the first report to prove that pancreatic cancer produced tissue factor in a patient with disseminated intravascular coagulation.

The authors describe a relation between the in vivo localized consumption of In-111 platelets and results of laboratory tests in a 82-year-old man with an aortic graft prosthesis who had chronic disseminated intravascular coagulation. In-111 platelets accumulated markedly over the abdominal aortic graft with a shortened platelet survival time and reflected changes in hematologic studies, which showed low platelet counts and a high concentration of fibrinogen degradation products in the plasma. If a strong clinical likelihood of local disseminated intravascular coagulation exists, then In-111 platelets may be valuable in localizing the focus of platelet consumption.

Unusual, intense splenic radioactivity was seen on bone scintigraphy with Tc-99m HMDP in a 14-year-old boy with alveolar rhabdomyosarcoma complicated by disseminated intravascular coagulation. Abnormal splenic radioactivity was resolved after recovery from the disseminated intravascular coagulation. During treatment of disseminated intravascular coagulation and tumors, the patient received repeated blood transfusions, resulting in iron overload, but this did not prevent the abnormal splenic uptake from resolving. This case indicates that disseminated intravascular coagulation may be a cause of splenic accumulation of bone-seeking agents, and that abnormal splenic uptake can be resolved.

Background: It is known that disseminated intravascular coagulation (DIC) may occur along with aortic aneurysms. To assess the localization of the active consumption site we performed 111In-oxine labeled platelet scintigraphy in patients with chronic aortic aneurysms., Methods: Images were obtained using 111In-oxine labeled autologous platelets in 45 patients. Planar images were taken twice (at 4 and 48 hrs) after injection. A visual inspection of the radioactivity uptake and special analysis in regions of interest were performed., Results: Thirty-five patients (78%) showed a focal accumulation of radioactivity in the aortic aneurysm. Six of 13 patients (46%) with dissecting aortic aneurysm, and 4 of 32 patients (12.5%) with true aneurysms were evaluated as negative uptake by scintigram (p < 0.05). The aneurysm/heart ratio was 0.85 +/- 0.16 (mean +/- SD) (4 hrs) and 1.09 +/- 0.15 (48 hrs) after injection; the aneurysm/liver ratio was 0.56 +/- 0.16 (4 hrs) and 0.38 +/- 0.09 (48 hrs); the aneurysm/spleen ratio was 0.39 +/- 0.07 (4 hrs) and 0.39 +/- 0.08 (48 hrs)., Conclusions: When the probability of DIC is clinically high in patients with aortic aneurysms, 111In-oxine labeled platelet scintigraphy provides useful preoperative information regarding the location of the functionally active consumption focus.

The purpose of this report is to provide an illustrative case of spontaneous hepatic and renal hematomas that occurred during a pregnancy complicated by preeclampsia and the HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome. The sonographic and computed tomographic findings included intrahepatic, subcapsular hepatic, and extracapsular perihepatic hematomas in addition to a large subcapsular renal hematoma. Since hepatic and renal hematomas that occur in association with preeclampsia and the HELLP syndrome are rare but potentially life-threatening complications, prompt laboratory and radiologic evaluations are essential and may reduce the associated morbidity and mortality.

Pulmonary lymphangiomatosis is a rare clinical and pathological entity which is distinct from lymphangiomyomatosis and from pulmonary lymphangiectasis. We report a case of a 20 year old man with diffuse lymphangiomatosis involving the mediastinum, lungs and retroperitoneum. The patient's intrathoracic lymphangiomatosis produced restrictive and obstructive impairment of his pulmonary function, but did not result in chylothorax or chylopericardium, which are two common manifestations of the disease. The patient's clinical course was remarkable for the concomitant development of chronic disseminated intravascular coagulation (DIC). Lymphangiomatosis involving both the mediastinum and pulmonary parenchyma is rare, and DIC is a very unusual complication of lymphangiomatosis.

Background: Congenital disseminated intravascular coagulation (DIC) has been reported in a variety of clinical settings, but to our knowledge, it has never been documented before birth. We describe prenatal identification of an umbilical cord vascular tumor and echogenic foci in the fetal liver leading to the diagnosis of fetal DIC by funipuncture., Case: A large vascular tumor of the umbilical cord was identified using prenatal sonography. At 31 weeks' gestation, echogenic areas, which were thought to represent infarcts or thrombi, were seen in the liver. When funipuncture revealed florid fetal DIC, delivery was accomplished by cesarean to prevent intracranial bleeding. Pathologic examination of the umbilical cord tumor showed it to be a large arteriovenous malformation., Conclusion: Arteriovenous malformations may cause fetal coagulopathy. This case illustrates that funipuncture may be used to diagnose this condition and that timely cesarean delivery may contribute to a favorable outcome.

Technetium bone scintigraphy was performed in four patients with fulminant meningococcemia and extensive peripheral gangrene. The bone scans showed variable levels of absent uptake in all extremities of the four patients who subsequently required quadrimembral amputations. In 13 limbs, the level of amputation was determined primarily by the bone scan findings, and operation was successful in 84% of those limbs. These findings suggest that bone scanning is a useful adjunct in differentiating viable from nonviable tissues in patients with extensive peripheral gangrene secondary to fulminant meningococcemia and thus helps determine the appropriate level of amputation in such patients.

The authors describe a seventy-six-year-old man with aortic graft, which became the focus of chronic disseminated intravascular coagulation (DIC). The patient had abdominal aortic aneurysm (AAA) and the size had increased up to 38 mm in diameter. The AAA was excised and replaced by Dacron graft. Ten months later, the DIC became chronic with renal dysfunction. Indium 111-labeled platelets scintigraphy showed increased accumulation of radioactivity over the graft. In the treatment of chronic DIC, low-dose subcutaneous heparin injection (5,000-10,000/day) was effective, and he was discharged. In this case there was also suspicion of lung cancer and recurrent aortic aneurysm, which were a more reasonable cause of chronic DIC. This case suggests that an aortic graft prosthesis may be a cause of localized chronic DIC and that indium 111-labeled platelets scintigraphy is useful for the detection of localized chronic DIC. Moreover, subcutaneous heparin administration may be effective for chronic DIC in patients with an abdominal aortic graft prosthesis.

We report the case of a premature female newborn of the 35th gestational week with a congenital mesoblastic nephroma. The tumor was prenatally diagnosed in the 32nd week of gestation. By close sonographic controls, rapid enlargement was verified towards the end of the 35th week of gestation. This was probably caused by hemorrhage into the tumor. Anemia and postnatal disseminated intravascular coagulation followed. Cesarean section was done, because the anemia was suspected by Doppler sonographic evaluation. Disseminated intravascular coagulation could not be sufficiently controlled by conservative means but only by surgical removal of the tumor. The tumor turned out to be a congenital mesoblastic nephroma by histologic evaluation. Despite postoperative anuria and catecholamine dependency, our patient eventually showed a very favourable outcome. Diagnosis, clinical behavior and therapy of this tumor with a generally good prognosis are described and discussed.

The importance of delayed or secondary brain insults in the eventual outcome of closed-head trauma has been documented in experimental models. To understand this phenomenon in the clinical setting, we studied a series of head-injured patients in whom multiple cranial computed tomographic (CT) scans were obtained. Patients whose follow-up CT studies revealed new intracranial lesions or worsening, compared with admission findings, were considered to have delayed cerebral injury. One hundred forty-nine (44.5%) of 337 consecutively studied patients developed delayed brain injury. There were highly significant associations (P < 0.001) between the appearance of delayed cerebral insults and the severity of the initial brain injury, the need for cardiopulmonary resuscitation in the field, the presence of coagulopathy at admission, and subdural hematoma on the initial CT scan. In addition, delayed injury was associated (P < 0.001) with higher mortality, slowed recovery, and poorer outcome at 6 months. Delayed brain injury was not significantly associated with patient age, sex, injury mechanism, associated injury, the need for endotracheal intubation in the field, early talking, CT abnormality other than intracranial hematoma, or type of residual neurological deficits. We used multiple regression analysis to explore the relationship between severity of injury, delayed insults, and outcome. As expected, the severity of the initial brain trauma contributed significantly to neurological outcome. The presence of delayed cerebral injury makes the outcome dramatically worse for each category of initial injury severity. The relationship between initial and secondary brain injury is discussed.

A 24-year-old man was brought to casualty after a fall. He suffered from head injury and multiple fractures. On arrival he was apneic and the heart was at a standstill. Resuscitation was successful and the patient was taken to the CT room to assess the extent of his head trauma. At the end of the procedure, maintaining adequate ventilation proved to be very difficult; the blood pressure was rapidly falling and the ECG showed severe bradycardia. Asystole followed and resuscitation was unsuccessful. Postmortem CT scanning of the chest revealed that the tracheobronchial tree was flooded with blood and coagulation profile showed the picture of disseminated intravascular coagulopathy. CT may be useful in the diagnosis of some pathological conditions when autopsy is difficult to perform.

Abnormalities of renal perfusion can be recognised more readily by sequential CT than by a plain CT scan or after "static" enhancement with contrast medium. Haemodynamically significant stenoses of the renal arteries and total, or partial, infarct can be diagnosed in this way. Intrarenal and capsular collaterals can be recognised by slow contrast accumulation in the infarcted area, or by the development of contrast in the sub-capsular portion of the cortex. Renal cortical necrosis is very well demonstrated by the absence of cortical perfusion; this is seen, for instance, in the DIC syndrome or during rejection after renal transplant.

Two patients are described who developed subarachnoid haemorrhage during pregnancy and the puerperium. In both patients there was clinical, haematological, histological, and renal angiographic evidence of the intravascular coagulation syndrome. No source of intracranial bleeding was demonstrated by bilateral carotid angiography in either patient. We suggest that the subarachnoid haemorrhage was a result of the intravascular coagulation syndrome in both patients.

In addition to a recently published case study, we present another three cases in which we observed both lung and renal uptake of technetium Tc 99m sulphur colloid which was related to a period of disseminated intravascular coagulation. Being familiar with this relationship may influence the diagnosis and course of the illness in certain patients.

Thirteen patients with acute subdural and epidural hematomas were found to have fresh, unclotted blood at the time of surgical decompression several hours after injury. Computed tomographic (CT) scans of these patients demonstrated areas of hyperdensity, corresponding to clotted hematoma, admixed with areas of isodensity, corresponding to liquid blood. Active bleeding from identifiable loci was found in 11 patients, 4 of whom had massive hemorrhages. Clotting abnormalities ranging from slightly elevated laboratory test results to a full-blown clinical picture of disseminated intravascular coagulation occurred in 8 patients. We describe the CT pictures of these "hyperacute" lesions, and we postulate that such CT presentations indicate either the presence of ongoing active intracranial bleeding or the onset of a coagulopathy complicating the management of these lesions.

Bovine fibrinogen was labelled with 125I using the chloramine T method or the iodogen method and the clottability of the preparations was studied in vitro and in vivo. Three days after radioiodination the in vitro clottability was 82.3% (chloramine T) and 80.4% (iodogen), respectively. When the solutions were allowed to stand at 4 degrees C for 13 days, the in vitro clottability decreased to 70% or 60%, respectively; either preparation was practically unclottable after 25 days. The preparations were administered to rats three days following radioiodination. They showed the same elimination rate and, on thrombin infusion, the same clottability. 125I-labelled (chloramine T) bovine fibrinogen stored in solution at -20 degrees C for 38 days showed a clottability of 76%, the in vivo clottability was unchanged.