Thrombin generation in Cushing's Syndrome: do the conventional clotting indices tell the whole truth?

Evaluation of coagulation profile in dogs with ACTH-dependent hyperadrenocorticism compared to healthy dogs by rotational thromboelastometry (ROTEM)

Despite their low morbidity, thromboembolic events in hyperadrenocorticism are associated with high mortality. Identifying the main hemostatic abnormalities will improve the prophylactic approach of these canine patients. The aim of this study was to evaluate hemostatic alterations related with ACTH-dependent HAC and its association with hypercoagulable state. For this purpose, 25 dogs diagnosed with ACTH-dependent HAC were compared with 28 healthy dogs as a control group. The hemostatic variables included platelet count, antithrombin, fibrinogen, D-dimer, PT, aPTT, rotational thromboelastometry (ROTEM) and platelet aggregation. Results showed a hypercoagulable state in 32% (8/25) dogs by ROTEM, which had at least 2 of the next features: decreased coagulation time (CT) or clot formation time (CFT) on INTEM (5/25) or EXTEM (4/25); increased maximum clot firmness (MCF) on INTEM (9/25), EXTEM (6/25) and FIBTEM (9/25). These same variables had a significant difference (P≤ 0.05) compared with the control group, as well as the parameters of α-angle and CT. Median fibrinogen levels (310 vs.178 mg/dL), mean platelet aggregation (11.1 vs. 7.9 Ohms), median platelet count (360 vs. 225 ×103/µL) and mean antithrombin activity (140 vs. 119%) were increased in ACTH-dependent HAC dogs compared to control group. PT (7.1 vs. 8.0 seconds) and aPTT (11.6 vs. 15.2 seconds) were also shortened in ACTH-dependent HAC dogs. Our findings confirm the presence of a hypercoagulable tendency in dogs with HAC. Although multifactorial, fibrinogen concentration and MCF FIBTEM showed the relevance of this protein for hypercoagulability in HAC.

Hemostatic balance between pro- and anticoagulant is maintained during glucocorticoid treatment

BACKGROUND

Glucocorticoids are associated with an increased risk of venous thrombosis. Glucocorticoid treatment increases coagulation factor and anticoagulant levels; however, its effect on hemostatic function remains unclear. This study aimed to investigate the changes in comprehensive coagulation profiles after glucocorticoid treatment in noninflammatory diseases to elucidate the direct contribution of glucocorticoids to hemostatic function.

PROCEDURE

Patients diagnosed with primary immune thrombocytopenia requiring glucocorticoid treatment were prospectively enrolled in this study. Changes in coagulation factors and anticoagulants during glucocorticoid treatment and changes in thrombin generation potential were determined in the absence and presence of soluble thrombomodulin (sTM).

RESULTS

Seven treatment cases (four for steroid pulse therapy and three for oral glucocorticoid therapy) in six patients with immune thrombocytopenia were examined. After glucocorticoid treatment, activated partial thromboplastin time significantly shortened, and activities of factor VIII, IX, XI, and XII significantly increased, except for von Willebrand factor antigen. Moreover, antithrombin and protein C (PC) activities significantly increased after glucocorticoid treatment. Two major parameters of thrombin generation potential, endogenous thrombin potential (ETP) and peak thrombin (Peak), significantly increased in the absence of sTM after glucocorticoid treatment. However, no significant increases in either parameter were observed in the presence of sTM. ETP-TM and Peak-TM ratios, which represent resistance to the anticoagulant effect of the PC pathway, significantly decreased after glucocorticoid treatment, suggesting that anticoagulant function via the PC pathway is elevated after glucocorticoid treatment.

CONCLUSIONS

As glucocorticoids increase intrinsic coagulation factor and anticoagulant levels, hemostatic balance between pro- and anticoagulant functions is maintained.

Blood coagulation dynamics during adrenocorticotropic hormone therapy in pediatric patients with infantile spasms

INTRODUCTION

Adrenocorticotropic hormone (ACTH) therapy is a first-line treatment for infantile spasms, which may rarely cause intracranial hemorrhage. However, the changes in blood coagulation during ACTH therapy are poorly understood, with little description in the management guidelines.

OBJECTIVE

To assess the changes in blood coagulation during ACTH therapy.

PATIENTS/METHODS

This retrospective study reviewed the medical records of 10 patients diagnosed with infantile spasms and treated with ACTH therapy, between January 2015 and March 2021. The underlying diseases included intracranial hemorrhage, hypoxic-ischemic encephalopathy, tuberous sclerosis, and cerebral infarction. Antiepileptic drugs administered were valproic acid (VPA), vitamin B6, zonisamide, topiramate, clobazam, clonazepam, and phenobarbital.

RESULTS

The 10 patients had a median age of 8 months (4-17 months) and included eight males. The median fibrinogen (Fbg) level before ACTH therapy was 202 mg/dL (125-392 mg/dL); however, this significantly decreased to 108.5 mg/dL (65-135 mg/dL) during treatment at a median of 12 days after (days 8-17) (p < 0.01). Decreased Fbg levels were observed with and without VPA. This suggests the possible influence of ACTH therapy on Fbg levels, irrespective of the VPA combination. Additionally, prothrombin time and activated partial thromboplastin time were significantly shortened when compared to those before ACTH therapy and at the lowest of Fbg levels.

CONCLUSIONS

Careful coagulation monitoring, especially during the second week of treatment, is necessary for the safe completion of ACTH therapy, with or without concomitant VPA.

Evaluation of procoagulant imbalance in Cushing's syndrome after short- and long-term remission of disease

OBJECTIVE

Patients with Cushing's syndrome (CS) are at high risk of venous thromboembolism related to a hypercoagulability due to procoagulant imbalance. However, whether these alterations are reversible after disease remission is still unclear. The endogenous thrombin potential (ETP) measured with and without the addition of thrombomodulin provides a global representation of coagulation and previous data confirmed hypercoagulable profile in patients with active hypercortisolism. Aim of this study was to assess the short- and long-term modification of ETP in patients with CS after disease remission.

DESIGN AND METHODS

Nineteen patients with CS for whom surgical remission was achieved, were prospectively evaluated for clinical characteristics, cortisol secretion profile and ETP at different time points: (i) before surgical intervention; (ii) after 6 months and (iii) 5 years from the time of persistent remission. Nineteen healthy subjects matched for age and gender were also evaluated as control group.

RESULTS

Before surgery, patients showed higher ETP-ratio (with/without thrombomodulin) than controls (0.62 ± 0.09-vs-0.56 ± 0.09, p = 0.034). No significant correlation between ETP-ratio and cortisol secretion was found. 6 months after remission, ETP-ratio was still significantly increased compared to controls (0.64 ± 0.09-vs-0.56 ± 0.09, p = 0.01), but was similar to baseline (0.64 ± 0.09-vs-0.62 ± 0.09, p = 0.87). At 5 years, ETP-ratio showed a significant decrease (0.55 ± 0.14-vs-0.62 ± 0.09, p = 0.02) and was comparable to controls (0.55 ± 0.14-vs-0.56 ± 0.09, p = 0.7).

CONCLUSIONS

Plasma hypercoagulability detected in patients with active hypercortisolism persists at short-term evaluation and seems to be completely reversible after long-term remission of disease. These data, as part of a whole evaluation of thrombotic risk, can contribute to make appropriate therapeutic choice in these patients.

Thrombin Generation Assay and Hemostatic Profile for Elucidating Hypercoagulability in Endogenous Canine Hyperadrenocorticism

Canine hyperadrenocorticism is a common endocrine disorder caused by chronic secretion of glucocorticoid, often associated with hypercoagulability and secondary thrombosis. The thrombin generation assay (TGA) evaluates hemostasis globally by measuring endogenous thrombin potential. We aimed to determine whether TGA is suitable for assessing hypercoagulability in dogs with endogenous hyperadrenocorticism (HAC), and to correlate TGA with coagulation markers including fibrinogen, antithrombin (AT), D-dimer, prothrombin time (PT) and activated partial thromboplastin time (aPTT), and with routine laboratory tests for elucidating prothrombotic mechanisms and evaluating their utility as hypercoagulability screening tests. Thrombin generation performed with high activator concentration showed significantly higher endogenous thrombin potential (ETP) (P = .0239) and peak thrombin (P = .0281) in Cushing patients. Fibrinogen (P = <.0001) and AT (P = .0444) activities were significantly higher in the HAC group, while those of PT (P = .0046) and aPTT (P = .0002) were lower. Basal cortisol levels correlated positively with fibrinogen (r = 0.4503; P = .0355) and negatively with AT activity (r = -0.4580; P = .0280). Fibrinogen and hematocrit values were inversely correlated (r = -0.4853; P = .0076). Our study confirmed the presence of higher thrombin generation in dogs with HAC. However, TGA performed with lower activator concentrations was unsuitable for detecting hypercoagulability. Higher AT and fibrinogen levels and lower aPTT activity were identified in dogs with HAC relative to controls suggesting a potential role for the combined use of these assays when assessing hypercoagulability in canine hyperadrenocorticism.

A multidisciplinary approach to the management of adrenal incidentaloma

An adrenal incidentaloma (AI) is an adrenal neoplasm incidentally discovered during an imaging unrelated to suspected adrenal disease. The aim of the present review is to offer practical guidance on the multidisciplinary approach of AIs.Areas covered:The prevalence of AI is high in the aging population (up to 5-8%); however, hormonally active or malignant conditions are rare. After the discovery of an AI, it is suggested to assess in parallel if the mass is potentially malignant and functionally active. The answer to the former question is mainly based on medical history (extra-adrenal malignancies, new-onset of signs or symptoms) and imaging (conventional radiology and/or nuclear medicine). The answer to the latter question is a complete endocrine evaluation of both cortical (glucocorticoids, mineralocorticoids) and medullary (catecholamines) secretion.Expert opinion:A multidisciplinary discussion is suggested for patients with adrenal disease, after the exclusion of nonfunctioning benign cortical adenoma, in order to plan a close and tailored follow-up for the suspected malignant or functioning forms. Surgery is advised for patients with malignant disease (adrenocortical cancer) or with clinically relevant secreting neoplasm (primary aldosteronism, Cushing's syndrome, and pheochromocytoma).

Thromboembolic disease in hypercortisolism

PURPOSE OF REVIEW

Endogenous Cushing's syndrome (CS) is associated with increased patient morbidity (hypertension, diabetes mellitus, dyslipidemia, visceral obesity, osteoporosis, cognitive alterations, and impaired quality of life). Both arterial and venous thromboembolic events (TE) due to alterations in the hemostatic system and prothrombotic state are widely reported in patients with CS, more so postoperatively. Increased mortality, if not appropriately treated, is largely due to cardiovascular events and infections.

RECENT FINDINGS

Patients with CS have markedly increased risk of thromboembolic episodes compared to the general population. The prothrombotic state is mediated by increased levels of procoagulant factors, but also by an impaired fibrinolytic capacity. All contribute to TE, atherosclerosis, and subsequent cardiovascular morbidity and mortality. Some abnormalities progressively improve after CS remission, but do not fully normalize for at least 1 year or more.

SUMMARY

Due to the additional thrombotic risk of surgery or any invasive procedure, anticoagulation prophylaxis should be at least considered in patients with CS and balanced with individual bleeding risk. However, a clear protocol of thromboprophylaxis is lacking and increased awareness regarding risks per se is needed. Large prospective trials will clarify, which patients with CS are at the highest risk and the optimal prevention protocol to minimize risks and maximize efficacy.

Use of Glucocorticoids and Risk of Venous Thromboembolism: A Narrative Review

Glucocorticoids are potent anti-inflammatory agents that are widely used for the treatment of many inflammatory, autoimmune, and neoplastic disorders. However, their beneficial effect is associated with several side effects, including an increased risk of cardiovascular complications, such as myocardial infarction and stroke. Whether their use also contributes to a procoagulant state, and therefore increases the risk of venous thromboembolism (VTE), is still a matter of debate. As an increased risk of venous thrombotic events is described in patients with Cushing's syndrome, which is characterized by endogenous hypercortisolism, it is reasonable to speculate that the chronic administration of glucocorticoids may induce a hypercoagulable state. However, it seems virtually impossible to separate the role of the drug from the underlying condition, which itself predisposes to the development of VTE. Actually, some evidence suggests that the use of exogenous glucocorticoids for the treatment of underlying disease and its exacerbations may further amplify the risk of VTE. Moreover, a procoagulant state has also been reported in healthy participants receiving oral glucocorticoids versus placebo. We have performed a concise narrative review on available data on the influence of exogenous glucocorticoids on hemostasis and their clinical impact on the risk of VTE.

Hypercoagulability in Cushing's syndrome: From arterial to venous disease

Cushing's syndrome (CS) is associated with multisystemic complications; the hematological system is not spared. Alteration in hemostatic parameters and in vivo endothelial dysfunction lead to increased thrombotic events. Arterial and venous thrombotic events carry significant morbidity and mortality. Death from cardiovascular and pulmonary embolism account for more than 50% of mortality. Surgery is a critical period; close to 50% of events occur in the 1-2 months after intervention. The evaluation and risk stratification of patients with CS is key to prevent events, balancing the risk-benefit of anticoagulation in this population. This current review will focus on up-to-date data on epidemiology, pathophysiology and management of hypercoagulability in CS.

The haemostatic system in acromegaly: a single-centre case-control study

PURPOSE

Although the mortality from acromegaly is due in most cases to an increased cardiovascular risk, no study has globally evaluated the haemostatic balance in acromegaly to ascertain the presence of hypercoagulability. We endeavoured to assess the overall coagulation profile in patients with acromegaly using both traditional and global coagulation assays.

METHODS

Consecutive outpatients with a diagnosis of acromegaly were enrolled and matched with healthy subjects. Whole blood thromboelastometry and impedance aggregometry, procoagulant, anticoagulant and fibrinolytic factors, as well as thrombin-generation assay and circulating endothelium-derived microvesicles were measured.

RESULTS

Forty patients (M/F 14/26, median age 59 years) with either new diagnosis (naïve, 14 cases) or treated acromegaly (26 cases) were enrolled in this study. Median time from diagnosis was 11 years. Levels of factor VIII and fibrinogen were significantly higher in acromegalic patients vs. controls (p = 0.029 and < 0.003, respectively). Overall, thromboelastometry parameters showed a faster coagulation formation with a more stable clot. Acromegaly patients showed significantly higher endogenous thrombin potential [ETP] and thrombin peak compared to controls (p = 0.016 and p < 0.001, respectively). ETP remained significantly higher (p < 0.001) when thrombomodulin was added. Endothelial-derived microvesicles were significantly higher in acromegaly patients than controls (52 [40.5-67] MVs/µL and 30 [18-80] MVs/µL, p = 0.03). Patients with untreated (naïve) acromegaly showed significantly reduced ETP with and without thrombomodulin vs. patients with treated acromegaly (p = 0.01).

CONCLUSION

Hypercoagulability in acromegaly is mainly due to higher levels of fibrinogen, factor VIII and thrombin generation, and appears to be more linked to the chronic phase of the disease.

Cushing's syndrome: Overview of clinical presentation, diagnostic tools and complications

Cushing's syndrome (CS) is a severe condition that results from chronic exposure to elevated circulating cortisol levels; it is a rare but potentially life-threating condition, especially when not timely diagnosed and treated. Even though the diagnosis can be straightforward in florid cases due to their typical phenotype, milder forms can be missed. Despite the availability of different screening tests, the diagnosis remains challenging as none of the available tools proved to be fully accurate. Due to the ubiquitous effect of cortisol, it is easy understandable that its excess leads to a variety of systemic complications including hypertension, metabolic syndrome, bone damages and neurocognitive impairment. This article discusses clinical presentation of CS with an eye on the most frequent cortisol-related comorbidities and discuss the main pitfalls of first- and second-line tests in endogenous hypercortisolism diagnostic workup.

Effects of pasireotide treatment on coagulative profile: a prospective study in patients with Cushing's disease

INTRODUCTION

Cushing's disease (CD) is characterized by procoagulative profile. Treatment with cortisol-reducing medications might normalize the coagulation impairment potentially eliminating the risk of thromboembolic complications.

AIM

The aim of this prospective study is to evaluate the effectiveness of 6-12 months of treatment with pasireotide (Signifor®, Novartis) 600 µg twice daily on coagulative factors in 21 patients (16 females, mean age 46 ± 12.2 years) with CD. Biochemical, hormonal (urinary free cortisol, UFC; late night salivary cortisol, LNSC; ACTH) and coagulative parameters as Protrombin time (PT), aPTT, factors VIII, IX and XI, antithrombin III, protein C, protein S, fibrinogen, were evaluated at baseline and during therapy.

RESULTS

UFC showed a significant reduction from baseline (3.2 ± 1.8 vs. 1.0 ± 0.8, p < 0.0001) with normalization in 13/21 (61.9%) and in 7/16 (43.8%) at 6 and 12 months, respectively. On the same way LNSC returned to normal in 5/11 at 6 months, showing a trend to reduction (8.6 ± 5 vs. 4.1 ± 2.9), even though without statistical significance (p = 0.07). Throughout the treatment period there was an increase in serum glycaemia (5.5 ± 2.3 vs. 6.8 ± 2.3 mmol/L, p = 0.09), with a concomitant significant increase in HbA1c after 6 months (40.7 ± 8.4 vs. 50.7 ± 12.3 mmol/mol, p = 0.006). Regarding coagulative parameters, no differences were found neither in clotting nor in anticoagulant factors during therapy. No patients developed thrombotic complication during treatment.

CONCLUSIONS

Pasireotide resulted an effective treatment in controlling hypercortisolism in more than half of CD patients with partial restoration also of circadian cortisol secretion. No significant improvements were observed on clotting factors; this fact might depend on persistence of typical alteration of CD, such as obesity and hypertension, and reflects also on the worsening in glucide metabolism induced by the drug. Clinical implications of persistent procoagulative impairment while on medical therapy should be considered.

Relationship between serum cortisol level and degree of false lumen thrombosis in patients with uncomplicated type B aortic dissection

Partial thrombosis of the false lumen in uncomplicated type B aortic dissection (uTBAD) is associated with an increased late mortality risk. Whether the serum cortisol level can affect false lumen thrombosis in patients with uTBAD has not been well characterized. This study was performed on 87 patients with uTBAD. A curve-fitting method was used to analyze the relationship between serum cortisol and partial thrombosis of false lumen. Univariate and multivariate logistic regression analyses were used to identify false lumen partial thrombosis–associated serum cortisol. Curve-fitting’s result revealed a characteristic U shape, and 14.0 µg/dL was considered as the cutoff point for serum cortisol. The results of univariate and multivariate logistic regression analyses suggested that when trisecting the serum cortisol level into three parts, the low and high levels of serum cortisol could significantly affect the occurrence of false lumen partial thrombosis compared with the middle level. The odds ratio value of the low and high levels of serum cortisol was 6.12 and 4.65, respectively, in the univariate analysis, and 24.32 and 3.93, respectively, in the multivariate analysis. Low or high levels of serum cortisol might influence the natural result of uTBAD through affecting the false lumen thrombosis.

Hypercoagulability and Risk of Venous Thromboembolic Events in Endogenous Cushing's Syndrome: A Systematic Meta-Analysis

Background: Hypercortisolism has been implicated in the development of venous thromboembolic events (VTE). We aimed to characterize VTE risk in endogenous Cushing's syndrome (CS) patients, compare that risk to other pathologies, and determine if there are any associated coagulation factor changes. Methods: Medline and Scopus search for "hypercortisolism" and "thromboembolic disease" from January 1980 to April 2017 to include studies that reported VTE rates and/or coagulation profile of CS patients. A systematic review and meta-analysis were performed. Results: Forty-eight studies met inclusion criteria. There were 7,142 CS patients, average age was 42 years and 77.7% female. Odds ratio of spontaneous VTE in CS is 17.82 (95%CI 15.24-20.85, p < 0.00001) when comparing to a healthy population. For CS patients undergoing surgery, the odds ratio (both with / without anticoagulation) of spontaneous VTE is 0.26 (95%CI 0.07-0.11, p < 0.00001)/0.34 (0.19-0.36, p < 0.00001) when compared to patients undergoing hip fracture surgery who were not treated with anticoagulants. Coagulation profiles in patients with CS showed statistically significant differences compared to controls, as reflected by increases in von Willebrand factor (180.11 vs. 112.53 IU/dL, p < 0.01), as well as decreases in activated partial thromboplastin time (aPTT; 26.91 vs. 30.65, p < 0.001) and increases in factor VIII (169 vs. 137 IU/dL, p < 0.05). Conclusion: CS is associated with significantly increased VTE odds vs. general population, but lower than in patients undergoing major orthopedic surgery. Although exact timing, type, and dose of anticoagulation medication remains to be established, clinicians might consider monitoring vWF, PTT, and factor VIII when evaluating CS patients and balance advantages of thromboprophylaxis with risk of bleeding.

Hypercoagulability in overweight and obese subjects who are asymptomatic for thrombotic events

The role of circulating microparticles (MP) of different origin and tissue factor (TF)-bearing in overweight and obese patients with and without metabolic syndrome is still a matter of debate. In a case-control study, the presence of hypercoagulability was evaluated in overweight and obese patients by measuring MP, thrombin generation (TG) and FVIIa-AT complexes. Twenty overweight patients (body mass index [BMI] range 25–29.9 kg/m2), 20 with I degree (30–34.9 kg/m2), 20 with II degree (35–39.9 kg/m2) and 20 with III degree obesity (≥ 40 kg/m2) were enrolled and compared to 40 age and gender-matched normal weight individuals. A significant increase in median levels of all MP subtypes was observed in the three degrees of obese patients compared to controls. Overweight patients had higher levels of annexin V-MP (AMP), endothelial-derived, leukocyte-derived and TF-bearing MP than controls. Obese patients had a significantly shorter median lag time (p< 0.05), higher median peak thrombin (p< 0.01) and increased median endogenous thrombin potential [ETP] (p< 0.001) compared to controls. Overweight subjects had significantly increased ETP compared to controls (p< 0.05). Both AMP levels and ETP were found to positively correlate with BMI, waist circumference, and inflammatory parameters. No significant increase in FVIIa-AT complex was seen in cases compared to controls. We conclude that obesity is associated with overproduction of procoagulant MP and increase TG. Interestingly, hypercoagulability is found in overweight patients free of metabolic syndrome and increases with the severity of obesity. Assessment of MP and TG may be helpful in the early characterisation of the prothrombotic state in obese patients.

Circulating microparticles in carriers of prothrombin G20210A mutation

Factor V Leiden (FVL) and prothrombin gene mutation G20210A (PTM) are the two most common genetic polymorphisms known to predispose carriers to venous thromboembolism (VTE). A recent study in FVL carriers showed that circulating levels of microparticles (MP) may contribute to their thrombogenic profile. To further elucidate the prothrombotic state linked to genetic thrombophilia, we extended this study to carriers of PTM. The plasma level of annexin V-MP, endothelial- MP (EMP), platelet-MP (PMP), tissue factor-bearing MP (TF+) and the MP procoagulant activity (PPL) was measured in 124 carriers of PTM (105 heterozygous and 19 homozygous) and in 120 age- and gender-matched healthy individuals. Heterozygous and homozygous carriers of PTM showed significantly increased levels of annexin V-MP (2930 [1440–4646] MP/μl and 3064 [2412–4906] MP/μl, respectively) and significantly shorter PPL clotting time (54 [46–67] sec and 55 [46–64] sec) compared to controls (1728 [782–2122] MP/μl and 71 [61–75] sec, respectively; p<0.01). Similarly, heterozygous and homozygous subjects presented with significantly higher levels of EMP, PMP and TF+ than controls (p<0.05). PTM carriers with a VTE history had significantly higher MP numbers and activity than controls. No significant difference was seen between carriers with and without a VTE history. We conclude that the higher levels of circulating MP found in PTM carriers may play a role in the development of VTE possibly by increasing thrombin generation. Further studies are needed to better define the role of MP as triggering factors for the thrombotic complications characterizing mild genetic thrombophilic defects.

Hypercoagulability in patients with Cushing disease detected by thrombin generation assay is associated with increased levels of neutrophil extracellular trap-related factors

Patients with Cushing disease (CD) are at increased risk of venous thromboembolism (VTE). It was surmised, but not conclusively shown that the risk is related to plasma hypercoagulability secondary to the glucocorticoids effect. This study is aimed at detecting hypercoagulability in patients with CD. Case-control study of 48 CD patients and controls enrolled at two Italian clinics for whom we assessed the thrombin-forming-potential in the presence of optimal activation of protein C obtained by adding into the assay system its main endothelial activator, thrombomodulin. These experimental conditions mimic more closely than any other test the in vivo situation. We observed enhanced thrombin-generation in CD patients, as shown by the modification of thrombin-generation parameters [i.e., shortened lag-time and time-to-peak, increased thrombin peak and endogenous thrombin potential (ETP)]. Moreover, the ETP ratio (with/without thrombomodulin), recognized as an index of hypercoagulability, was increased in patients as compared to controls. We attempted to explain such hypercoagulability by measuring both procoagulant and anticoagulant factors, and some other non-coagulation parameters (i.e., neutrophil extracellular traps (NET), recently associated with the VTE risk and/or increased hypercoagulability. We showed that the hypercoagulability in patients with CD is associated with increased levels of factor VIII and NET-related variables. We detected plasma hypercoagulability in patients with CD and found experimental explanation for its occurrence. Whether this hypercoagulability can entirely explain the occurrence of VTE in patients with CD should be investigated by ad-hoc clinical trials. However, until these studies will be available the evidence supports the concept that patients with CD are candidates for antithrombotic prophylaxis.

A venous thromboembolism risk assessment model for patients with Cushing's syndrome

Cushing's syndrome (CS) is associated with an incidence of venous thromboembolism (VTE) about ten times higher than in the normal population. The aim of our study was to develop a model for identifying CS patients at higher risk of VTE. We considered clinical, hormonal, and coagulation data from 176 active CS patients and used a forward stepwise logistic multivariate regression analysis to select the major independent risk factors for thrombosis. The risk of VTE was calculated as a 'CS-VTE score' from the sum of points of present risk factors. VTE developed in 20 patients (4 pulmonary embolism). The group of CS patients with VTE were older (p < 0.001) and had more cardiovascular events (p < 0.05), infections and reduced mobility (both p < 0.001), higher midnight plasma cortisol levels (p < 0.05), and shorter APTT (p < 0.01) than those without. We identified six major independent risk factors for VTE: age ≥69 years and reduced mobility were given two points each, whereas acute severe infections, previous cardiovascular events, midnight plasma cortisol level >3.15 times the normality and shortened APTT were given one point each. A CS-VTE score <2 anticipated no risk of VTE; a CS-VTE score of two mild risk (10 %); a CS-VTE score of three moderate risk (46 %); a CS-VTE score ≥4 high risk (85 %). Considering a score ≥3 as predictive of VTE, 94 % of the patients were correctly classified. A simple score helps stratify the VTE risk in CS patients and identify those who could benefit from thromboprophylaxis.

Mechanisms in endocrinology: The spectrum of haemostatic abnormalities in glucocorticoid excess and defect

Glucocorticoids (GCs) target several components of the integrated system that preserves vascular integrity and free blood flow. Cohort studies on Cushing's syndrome (CS) have revealed increased thromboembolism, but the pathogenesis remains unclear. Lessons from epidemiological data and post-treatment normalisation time suggest a bimodal action with a rapid and reversible effect on coagulation factors and an indirect sustained effect on the vessel wall. The redundancy of the steps that are potentially involved requires a systematic comparison of data from patients with endogenous or exogenous hypercortisolism in the context of either inflammatory or non-inflammatory disorders. A predominant alteration in the intrinsic pathway that includes a remarkable rise in factor VIII and von Willebrand factor (vWF) levels and a reduction in activated partial thromboplastin time appears in the majority of studies on endogenous CS. There may also be a rise in platelets, thromboxane B2, thrombin-antithrombin complexes and fibrinogen (FBG) levels and, above all, impaired fibrinolytic capacity. The increased activation of coagulation inhibitors seems to be compensatory in order to counteract disseminated coagulation, but there remains a net change towards an increased risk of venous thromboembolism (VTE). Conversely, GC administered in the presence of inflammation lowers vWF and FBG, but fibrinolytic activity is also reduced. As a result, the overall risk of VTE is increased in long-term users. Finally, no studies have assessed haemostatic abnormalities in patients with Addison's disease, although these may present as a consequence of bilateral adrenal haemorrhage, especially in the presence of antiphospholipid antibodies or anticoagulant treatments. The present review aimed to provide a comprehensive overview of the complex alterations produced by GCs in order to develop better screening and prevention strategies against bleeding and thrombosis.

Perioperative thromboprophylaxis in Cushing's disease: What we did and what we are doing?

PURPOSE

Cushing's disease (CD) is associated with an increased risk of thrombotic events, particularly after surgery. No guidelines are available on the management of patients with CD undergoing pituitary transsphenoidal surgery (TSS). We aimed to compare the effectiveness of different prophylactic procedures on the prevention of thrombotic events after surgery in CD.

METHODS

We retrospectively collected data on 78 consecutive patients who underwent TSS for CD between 2001 and 2012 at Padova's Neurosurgical Unit, recording their hemostatic, hormonal and anthropometric parameters. Patients were divided into two groups according to their perioperative management. Group A (34 patients) received fractionated heparin for a maximum of 14 days after surgery. Patients in group B (44 patients) were given no early glucocorticoid replacement therapy, and treated with subcutaneous enoxaparin 4,000-8,000 U/daily (depending on their weight) for 30 days plus graduated elastic stockings until mobilization, and early ambulation.

RESULTS

The whole cohort of patients had clotting and anticoagulant factors significantly higher than the normal range. The two groups were comparable for age, BMI, ACTH, urinary free cortisol levels, outcome of surgery, and main clotting parameters. The surgical procedure did not change during the study period. Three venous thrombotic events [venous thromboembolic events (VTE), 2 associated with pulmonary embolism] were recorded in group A, none in group B (p = 0.079). No hemorrhagic events were reported.

CONCLUSIONS

Provoked thrombotic events pose a major problem in the management of CD patients after surgery, regardless of the procedure's outcome. The prophylactic regimen proposed in this paper afforded an efficacy prophylaxis against postoperative VTE in patients with CD. Due to the rarity of CD, a multicenter study on a larger sample of cases would be warranted in order to collect more thrombotic events.