SARS-CoV-2 systemic infection in a kidney transplant recipient: sequence analysis in clinical specimens

OBJECTIVE

Herein we report clinical and virological data in a patient with COVID-19 infection and a prior history of kidney transplantation who had a good clinical recovery despite systemic infection.

PATIENTS AND METHODS

Reverse transcriptase quantitative PCR analysis for the RdRp, N and E target genes detected viral RNA in different types of biological specimens. Whole viral genome sequences were obtained and analyzed from respiratory tract, feces and blood.

RESULTS

Viral sequences showed high (~99.9%) homology with the Wuhan seafood market pneumonia virus. Phylogenetic analysis assigned of the SARS-CoV-2 strains to clade G. A rare variant in the orf1ab gene was present in both sequences, while a missense variant was detected only in viral RNA from stool.

CONCLUSIONS

The evolution of the COVID-19 systemic infection in the patient presented here was favorable to the hypothesis that immunosuppressive therapy in organ transplant recipients might be involved in viral dissemination. A missense mutation was present in only one specimen from the same patient implying the occurrence of a mutational event in viral RNA, which is suggestive for the presence of an active virus, even though viral isolation is necessary to demonstrate infectivity.

Is population genetic structure of vascular plants shaped more by ecological or geographic factors? A study case on the Mediterranean endemic Centaurea filiformis (Asteraceae)

All known populations of the Sardinian endemic Centaurea filiformis Viv. (Asteraceae) were studied in order to understand the impact of both geographic and ecological factors on the genetic structuring of this species. Fourteen populations and 234 individuals were sampled. The demographic structure of the populations and the reproductive ecology were estimated in 28 plots. Population genetic analyses were based on SSR markers. Genetic structure was investigated by spatial Bayesian methods. Average densities of 0.51 individuals m^-2 were detected, with a prevalence of adults. Ten species of pollinators were identified; C. filiformis ability to self-pollinate and myrmecochory were demonstrated experimentally. The populations displayed an average heterozygosity value of H_e  = 0.576 and high genetic differentiation (overall F_ST  = 0.218). Bayesian analysis suggests that five is the most probable number of gene pools of origin. A strong correlation between geographic distances and genetic distances among populations was highlighted. The demographic population structure of C. filiformis is dominated by adults, suggesting that it is a stable-regressive or senile species, investing more in local persistence than colonisation ability. Despite the scattered distribution, the populations studied do not present evidence of genetic erosion. The analysis of genetic differentiation reveals very high differentiation levels among populations, thus indicating that effective barriers exist against gene flow. A general conclusion is that population distribution results in a clear genetic structure for the populations studied, and that geography and not ecology is shaping the present distribution of this species.

Humoral immunity response to human endogenous retroviruses K/W differentiates between amyotrophic lateral sclerosis and other neurological diseases

BACKGROUND AND PURPOSE

Human endogenous retroviruses (HERV) K/W seem to play a role in fostering and exacerbation of some neurological diseases, including amyotrophic lateral sclerosis (ALS). Given these findings, the immunity response against HERV-K and HERV-W envelope surface (env-su) glycoprotein antigens in serum and cerebrospinal fluid (CSF) was investigated for ALS, multiple sclerosis (MS) and Alzheimer's disease patients and in healthy controls.

METHODS

Four antigenic peptides derived respectively from HERV-K and HERV-W env-su proteins were studied in 21 definite or probable ALS patients, 26 possible or definite relapsing-remitting MS patients, 18 patients with Alzheimer's disease and 39 healthy controls. An indirect enzyme-linked immunosorbent assay was set up to detect specific antibodies (Abs) against env-su peptides.

RESULTS

Amongst the measured levels of Abs against the four different HERV-K peptide fragments, only HERV-K env-su_19-37 was significantly elevated in ALS compared to other groups, both in serum and CSF. Instead, amongst the Abs levels directed against the four different HERV-W peptide fragments, only HERV-W env-su_93-108 and HERV-W env-su_248-262 were significantly elevated, in the serum and CSF of the MS group compared to other groups. In ALS patients, the HERV-K env-su_19-37 Abs levels were significantly correlated with clinical measures of disease severity, both in serum and CSF.

CONCLUSIONS

Increased circulating levels of Abs directed against the HERV-W env-su_93-108 and HERV-W env-su_248-262 peptide fragments could serve as possible biomarkers in patients with MS. Similarly, increased circulating levels of Abs directed against the HERV-K env-su_19-37 peptide fragment could serve as a possible early novel biomarker in patients with ALS.

Identification of a HERV-K env surface peptide highly recognized in Rheumatoid Arthritis (RA) patients: a cross-sectional case-control study

Endogenous retroviruses (HERV) are believed to be pathogenic in several autoimmune diseases. Among them, HERV-K viruses have been reported recently to be involved in the pathogenesis of rheumatoid arthritis (RA). In this study we have explored the role of humoral immune response against HERV-K as a potential pathogenetic mechanism in RA. Four different peptides from the extracellular portion of the env protein of HERV-K (env-su_19-37 , env-su_109-126 , env-su_164-186 , env-su_209-226 ) were selected by bioinformatic analysis on the basis of their putative immunogenicity. Indirect enzyme-linked immunosorbent assay (ELISA) was then carried out to quantify antibodies against those peptides on blood samples of 70 consecutive RA patients and 71 healthy controls (HC). Differences between the two groups were analysed using the Mann-Whitney test. Potential correlations between RA laboratory, clinical descriptors and immunoglobulin (Ig)G levels were explored by bivariate regression analysis. Serum autoantibodies against one of four tested peptides of HERV-K (env-su_19-37 ) were significantly higher in RA than in HC (19 versus 3%, P = 0·0025). Subgroup analysis showed no association between anti-HERV-K peptide humoral response and clinical, serological and clinimetric RA disease descriptors. Serum from RA patients in our series reacted significantly against HERV-K env-su_19-37 peptide in comparison to the general population suggesting a role for the HERV-K- related, secondary antigenic-driven immune response in the pathogenesis of RA. Further studies are needed to confirm these results and to explore the role of this HERV-K surface peptide as a potential therapeutic target.

Combining HLA-DRB1-DQB1 and Mycobacterium Avium Subspecies Paratubercolosis (MAP) antibodies in Sardinian multiple sclerosis patients: associated or independent risk factors?

BACKGROUND

Amongst Sardinians the human leukocyte antigen (HLA) DRB1-DQB1 haplotypes *15:02-*06:01, *16:01-*05:02, *14:01-4-*05:03 are protective for multiple sclerosis (MS), while *13:03-*03:01, *04:05-*03:01, *03:01-*02:01, *15:01-*06:02 and Mycobacterium avium subspecies paratubercolosis (MAP) are predisposing factors. We studied the correlation between MAP and HLA.

METHODS

Five hundred thirty-one patients were searched for anti-MAP2694 antibodies, DRB1-DQB1 genotyping was performed. The haplotypes were classified as predisposing, neutral or protective.

RESULTS

Anti-MAP2694 were found in 23 % of subjects carrying one protective HLA versus 32 % without (p = 0.04).

CONCLUSIONS

We showed a lower frequency of Abs in patients with protective HLA. These haplotypes could have a protective role for both MS and MAP.

Multiple sclerosis-associated retrovirus and optic neuritis

One prognostic factor for early multiple sclerosis (MS) patients to develop a definite MS may be the presence of the MS-associated retrovirus (MSRV) in the cerebrospinal fluid (CSF). We designed a specific study on a cohort of optic neuritis (ON) patients to evaluate the MSRV-dependent conversion to MS relative to the prediction conferred by magnetic resonance imaging (MRI) and CSF abnormalities. At follow-up, 33.3% MSRV+ and 0% MSRV− ON patients developed MS ( P=0.03). The prediction value is lower than that given by CSF and MRI abnormalities (42.3%). This intriguing finding is discussed in the light of the abundant discrepancies observed in the MSRV literature.

Multiple sclerosis-associated retrovirus in early multiple sclerosis: a six-year follow-up of a Sardinian cohort

The human endogenous retroviruses (HERV)-W family contains an extracellular particle detected in multiple sclerosis (MS) patients and designated as MS-associated retrovirus (MSRV). Through nested RT-PCR assays specific for pol MSRV gene, we preliminary reported that its presence in the cerebrospinal fluid (CSF) of early MS patients could be indicative of a poor prognosis upon a three-year follow-up. In the present clinical study, we enlarged our blind observation up to six years. At study entry, 10 MS patients were MSRV- and eight were MSRV+ in the CSF, both groups having a similar mean age and Expanded Disability Status Scale (EDSS) score. After six year follow-up, the mean EDSS significantly differed between the MSRV- and MSRV+ cohorts (4.3 versus 2.2; P = 0.004), as did the annual relapse rate (0.5 in the MSRV- versus 0.3 in the MSRV+; P = 0.01). Finally, two MSRV- patients entered the progressive phase, whilst none of the MSRV+ group entered this phase, and 9/10 MSRV- versus 2/8 MSRV+ patients were treated with immunomodulatory or immunosuppressive drugs (P = 0.009). In conclusion, we found that the presence of MSRV virions in the CSF at the onset of MS is associated, not only with disability accumulation, but also with a higher rate of clinical re-exacerbations. With the known potential pathogenic effects of MSRV given in the literature, further investigations on MSRV are warranted.

Immune response induced by Epstein-Barr virus and Mycobacterium avium subsp. paratuberculosis peptides in current and past infectious mononucleosis: a risk for multiple sclerosis?

BACKGROUND AND PURPOSE

Infectious mononucleosis (IM) caused by Epstein-Barr virus (EBV) has been associated with increased risk of multiple sclerosis (MS). However, the mechanism linking these pathologies is unclear. Different reports indicate the association of EBV, and recently Mycobacterium avium subsp. paratuberculosis (MAP), with MS. For a better understanding of the role of these pathogens, the host response induced by selected antigenic peptides in subjects with a history of IM that significantly increases the risk of MS was investigated.

METHODS

Both humoral and cell-mediated response against peptides able to induce a specific immune activation in MS patients deriving from lytic and latent EBV antigens BOLF1(305-320), EBNA1(400-413), from MAP MAP_4027(18-32), MAP_0106c(121-132) and from human proteins IRF5(424-434) and MBP(85-98) in subjects with current and past IM were examined.

RESULTS

EBNA1 and MAP_0106c peptides were able to induce a humoral immune response in subjects with a history of clinical IM in an independent manner. Moreover, these peptides were capable of inducing pro-inflammatory cytokine interferon γ by CD4+ and CD8+ T lymphocytes and interleukin 6 and tumour necrosis factor α by CD14+ monocyte cells.

CONCLUSION

Our results highlight that EBV and MAP may be involved independently in the same causal process leading to MS in subjects with a history of IM.

HPV infection in HIV-positive females: the need for cervical cancer screening including HPV-DNA detection despite successful HAART

PURPOSE

To identify the presence of Human Papilloma Virus (HPV) infection and evaluate the role of Highly Active Antiretroviral Treatment (HAART) in patients with HIV-HPV co-infection. We also compared cytological screening results with HPV-DNA detection to implement screening programs and prevention of invasive cervical cancer (ICC) in HIV-infected females.

PATIENTS AND METHODS

We enrolled HIV-infected females presenting for routine clinical evaluation. HPV-DNA of high/intermediate and low-risk types was detected from cervical specimens by nucleic acid hybridization assay with signal-amplification. Patients were divided into two groups according to the presence of HPV co-infection (HPV+) or not (HPV-).

RESULTS

We enrolled 57 HIV-infected females. Median age was 40 (IQR 35-44) years, mean CD4 count was 547 ± 227 cells/mm(3), 45 (78.9%) had undetectable HIV-RNA and 52 (91.2%) received HAART. Globally, 19/57 (33.3%) patients were HPV-infected, 16/57 (28.1%) with high/intermediate and 3/57 (5.3%) with low-risk types. Five of the 19 (26.3%) HPV+ patients carried both types. Correlating high-risk genotype HPV-DNA detection with cytology, 17.5% of women with negative cytology, 36.4% with ASCUS (Atypical Squamous Cells of Uncertain Significance) and 83.4% of women with positive cytology (50% of LSIL: low-grade squamous intraepithelial lesion and 100% of HSIL: high grade SIL) were HPV positive. No statistical difference when comparing HPV+ and HPV-patients in age, CD4 cell count, in the proportion of previous intravenous-drug use, previous AIDS and of those receiving HAART with undetectable HIV-RNA was observed.

CONCLUSIONS

Cervical cancer screening including HPV-DNA detection should be implemented in HIV infected females across Europe, also when receiving successful HAART, to early identify the HIV patients at risk for ICC to be submitted to more frequent follow up and proper treatment.

Multiple sclerosis-associated retrovirus and progressive disability of multiple sclerosis

Retrovirus-like particles containing the multiple sclerosis-associated retrovirus RNA, significantly found in the cerebrospinal fluid of patients with multiple sclerosis, have been preliminarily associated with a short-term poor clinical and radiological prognosis of the disease. We asked whether these prognostic indications are still measurable after a long-term clinical evaluation (10 years). Our 10-year blind observational study confirms that the presence of multiple sclerosis-associated retrovirus in the cerebrospinal fluid of early multiple sclerosis patients is associated with a significantly greater rate of relapse-unrelated unremitting disability and secondary progression of the disease.

p73 modulates HIV-1 Tat transcriptional and apoptotic activities in human astrocytes

HIV-1 Tat is a potent transcriptional activator of the viral promoter with the ability to modulate a number of cellular regulatory circuits including apoptosis. Tat exerts its effects through interaction with viral as well as cellular proteins. Here, we studied the influence of p73, a protein that is implicated in apoptosis and cell cycle control, on Tat apoptotic function in the central nervous system. We recently demonstrated the ability of Tat to associate with p73, and that this association modulates Tat transcriptional activity (Amini et al., Mol Cell Biol 2005; 18: 8126-8138). We demonstrated that p73 interferes with Tat-mediated apoptosis by preventing the up-regulation of Bax and down-regulation of Bcl-2 proteins in astrocytes. Thus, the interplay between Tat and p73 may affect Tat contribution to apoptotic events in the brain, limiting its involvement in the neuropathology often observed in the brains of HIV-1 patients.

Multiple sclerosis-associated retrovirus and MS prognosis: an observational study

MS-associated retrovirus (MSRV) in the CSF may have gliotoxic properties and could be associated with a more disabling MS. The authors tested this hypothesis in 15 untreated patients with MS: 6 MSRV- and 9 MSRV+ at the time of CSF withdrawal. After a 3-year mean follow-up, MSRV- patients showed a stable MS course, whereas MSRV+ patients had a progressive course (p = 0.01).

Apathetic Graves' disease and acquired hemophilia due to factor VIIIc antibody

Acquired hemophilia due to autoantibody to Factor VIII coagulant (Factor VIIIc) is a rare event which may be observed in patients with different autoimmune diseases. To our knowledge, this association has been reported only once in patients with autoimmune thyroid disease. Here we describe a patient presenting with a severe hemorrhagic disorder due to Factor VIIIc antibody in whom biochemical screening for thyroid diseases led to a diagnosis of hyperthyroid Graves' disease not associated to overt clinical features. This case underlines the importance of carrying out a complete screening for autoimmunity, including thyroid autoimmune disease, in all patients with apparently isolated serum Factor VIIIc inhibitors.

Multiple sclerosis-associated retrovirus (MSRV) in Sardinian MS patients

Blood and CSF of Sardinian patients with MS and neurologic control subjects were tested for MS-associated retrovirus (MSRV). CSF detection in MS was 50% at clinical onset, increasing with temporal disease progression, and 40% in control subjects. In blood, MSRV was detected in all MS patients, in most patients with inflammatory neurologic diseases, and rarely in healthy blood donors. MSRV may represent a marker of neurologic diseases of inflammatory origin.

Multiple sclerosis and multiple sclerosis-associated retrovirus in Sardinia

The island of Sardinia has a high and increasing incidence of multiple sclerosis (MS). In a search for environmental factors that may account for this anomalously high incidence, we looked for evidence of multiple sclerosis-associated retrovirus (MSRV) that has previously been found in the plasma and cerebrospinal fluid of MS patients. We studied 25 MS patients and 25 matched healthy controls of ascertained Sardinian lineage. Blood samples were processed for extracellular RNA extraction. RNAs underwent reverse transcription/nested polymerase chain reaction (RT-PCR) with primers specific for MRSV-pol gene. We found a striking correlation between MSRV positivity and MS disease, but the virus was found also only in controls (100% and 12% respectively; Fisher's exact test, p<0.00001). It is unclear whether MSRV exerts any pathogenic role in MS. It is possible that this is simply an epiphenomenon, but even then, it may constitute a diagnostic marker.

Fibrinopeptide A, prothrombin fragment 1 + 2, thrombin-antithrombin complex and D dimer before and after injection of a nonionic contrast medium (iohexol)

The principal aim of this study was to evaluate, on biochemical grounds, whether injection of a low-osmolar nonionic contrast medium (iohexol) can induce a prothrombotic state and/or a change in fibrinolysis. Fifteen patients were submitted to urographic examination and the assays listed below were performed: before the injection (T0), 1 h after (T1), and 24 h after (T24) the injection of the contrast medium. The following assays were performed: fibrinopeptide A (FPA), prothrombin fragment 1+2 (F1+2), thrombin-antithrombin complex (TAT) and D dimer (D-D). The assays were carried out on 6 of the patients to whom a saline infusion was administered. Only a mild statistically significant increase was found in FPA levels at 1 h after injection of the contrast medium (mean and CI 95%: T0 4.4, 3.7-5.5; T1 6.0, 4.9-9.1; p = 0.003). F1+2, TAT and D-D did not show any significant change after the injection. These findings show that after injection of iohexol, only a mild, though statistically significant, increase in FPA levels was observed as an expression of increased thrombin activity. In the absence of any significant increases in TAT, F 1+2 and D-D, we have no evidence of a prethrombotic state.

Are prothrombin fragment 1 + 2 and thrombin-antithrombin complexes useful in the management of oral anticoagulant therapy?

We investigated the behavior of prothrombin fragment F1 + 2 and thrombin-antithrombin complexes in 70 patients treated with chronic anticoagulant therapy. Moreover, in a longitudinal study 37 patients were evaluated twice and 16 patients three times. Twenty-eight age- and sex-matched healthy subjects were also studied as a control group. Prothrombin fragment F1 + 2 or thrombin-antithrombin values among patients with different International Normalized Ratios, nor in the same patients studied two or three times. Our results confirm that oral anticoagulant treatment can effectively reduce thrombin activity. However, strong anticoagulation does not induce a further significant decrease in fragment F1 + 2 values. Therefore, we feel measurement of fragment F1 + 2 might be less useful than thought in optimizing oral anticoagulant therapy.

Is there a hypercoagulable state in military fighter pilots?

BACKGROUND

A hypercoagulable state is associated with an increased incidence of cardiovascular disease, the most important cause of permanent grounding of flying personnel.

HYPOTHESIS

The aim of our study was to investigate whether a hypercoagulable state is present in jet pilots, and whether it can be due to flight activity.

METHOD

To this purpose we studied Fibrinopeptide A (FPA), Thrombin-Antithrombin complexes (TAT) and D-Dimer (DD), sensitive biochemical markers of blood coagulation and fibrinolysis activation, in 10 jet pilots after a standardized training flight mission, and in a control group. Also evaluated before flight were 6 jet pilots.

RESULTS

We were able to show increased thrombin and plasmin activity both in jet pilots compared to the control group, and after flight in the 6 pilots who were evaluated twice.

CONCLUSION

We conclude that a hypercoagulable state due to flight activity is present in jet pilots after flight. Possible mechanisms involve an effect of psycho-physical stress mediated by a neuroendocrine response to flight activity, or an effect of chronic +Gz exposure on cardiovascular structure and function.

Controlled vitamin K content diet for improving the management of poorly controlled anticoagulated patients: a clinical practice proposal

The aim of our study was to investigate the effect of a diet with a known vitamin K content on the monitor test for oral anticoagulant therapy. We studied 10 poorly controlled patients (7 women and 3 men, mean age 48 +/- 15 years) in therapy with acenocoumarol for at least 1 year. Another group of 10 poorly controlled patients was considered as a control group. After a baseline period, during which a free diet was allowed, patients were administered a diet with a controlled vitamin K content; in the same period, control subjects were not subjected to any dietary restriction. Thrombotest (Nyegaard, Oslo) was employed for monitoring oral anticoagulant therapy, with a therapeutic range between 2.3 and 4.8 INR. We found a significant difference by thrombotest between the percentages within the therapeutic range obtained before and during dietary treatment (p = 0.0001). The difference in percentages was -0.31 and the 95% CI, of the difference ranged from -0.45 to -0.17. No significant difference was shown in the control group in the same periods. Our data suggest that a diet with a controlled vitamin K content is effective in increasing the percentage of tests within the therapeutic range in patients with poorly controlled anticoagulation.

Activation of blood coagulation and fibrinolysis in Graves' disease

We studied blood coagulation and fibrinolysis activities in hyperthyroidism before and after methimazole or 131I. Fibrinopeptide A and B beta 15-42, in vivo indicators of thrombin and plasmin activity, were measured by RIA, while fibrinogen by the Clauss method. We studied 50 patients, affected by toxic diffuse goiter. We evaluated 21 of them before and after treatment. Fibrinogen, fibrinopeptide A, and B beta 15-42 were higher in patients than in controls (p less than 0.0001). There was no difference in fibrinopeptide A nor in B beta 15-42 before or after treatment. In euthyroidism fibrinogen returned to normal values. Inflammation of the thyroid gland secondary to autoimmunity may activate blood coagulation by release of tissue factor. High fibrinogen before treatment may be explained as an aspecific response. Since it persists in euthyroidism, autoimmunity could account for high fibrinopeptide A and B beta 15-42 aftertreatment.

[Streptococcus mitis endocarditis. Description of a clinical case]

The diagnostic iter of a case of Streptococcus mitis endocarditis is reported. Bacterial endocarditis was diagnosed in a 32-year-old patient following ultrasound cardiography and microbiological tests. The paper stresses the importance of ultrasound cardiography in the diagnosis of bacterial endocarditis.

Bleeding time is prolonged during oral anticoagulant therapy

We have performed the BT test in 55 patients undergoing oral anticoagulant therapy monitored by means of Thrombotest (TT). Patients in steady state of anticoagulation showed longer BT than normal controls; patients in overdose phase had longer BT values than either controls or patients in steady state. After recovery the overdose phase patients showed BT values not different from those of the controls. Moreover we were able to find in our patients a significant linear correlation between BT and TT. Impairment in primary haemostasis could be due either to a scarce fibrin deposition in the haemostatic plug or to deficiency of a possible vitamin K dependent vascular "bleeding factor".

Is the imbalance between thrombin and plasmin activity in diabetes related to the behaviour of antiplasmin activity?

The aim of this study was to evaluate the balance between thrombin and plasmin activity in a group of 79 diabetic patients (IDDM and NIDDM). For this purpose we determined fibrinopeptide A (FPA) and B beta 15-42, specific products of thrombin and plasmin activity. Moreover we investigated the behaviour of antithrombin III and alpha 2 antiplasmin, important inhibitors of blood coagulation and fibrinolysis. Results show an increase both in FPA and B beta 15-42 in IDDM and NIDDM patients when compared to healthy controls. However the ratio between B beta 15-42 and FPA was lower than in controls indicating an imbalance between thrombin and plasmin activity. Antithrombin III levels were not different from the controls and no correlation was found with Hb A1c. alpha 2 antiplasmin was found to be higher in IDDM when compared both with NIDDM and controls. A non linear correlation was found between Hb A1c and alpha 2 AP in both diabetic groups. We conclude that the imbalance between thrombin and plasmin activity may have a role in determining fibrin deposition. These subclinical abnormalities, unrelated to vascular complications and duration of the disease, may progressively contribute to the development of the vascular complications in diabetes.

[Activity of the coagulation and fibrinolysis in non-insulin-dependent diabetes mellitus. In vivo study]

In vivo study of blood coagulation and fibrinolysis activities in non insulin dependent diabetes mellitus. The aim of the study was to investigate in vivo blood coagulation and fibrinolysis activities in a group of diabetic patients NIDDM with and without vascular complications. For this purpose we determined two sensitive indicators in vivo of blood coagulation and fibrinolytic activities such as fibrinopeptide A and B beta 15-42 respectively. Moreover, we computed the ratio between B beta 15-42 and fibrinopeptide A in order to investigate a possible imbalance in vivo between blood coagulation and fibrinolysis. Control groups were 15 healthy subjects and 28 non diabetic patients affected by atherosclerotic disease. Fibrinopeptide A and B beta values were significantly higher in the diabetic patients than controls but there was no difference between the former group and the atherosclerotic patients. Also, no correlation was found for FPA, B beta, B beta/FPAr and HbAlc, fructosamine and blood glucose levels. There was no difference in B beta, FPA and B beta/FPAr values for patients treated with insulin and for those treated with either hypoglycemic agents or diet. Our data indicate that in diabetic patients fibrinolysis activity is increased, but it cannot counterbalance thrombin activity which appears much more enhanced. Finally, the lack of correlation for FPA, B beta, B beta/FPAr and HbAlc, fructosamine and blood glucose suggests that blood coagulation and fibronolysis abnormalities are not related to the degree of blood glucose control.

Subclinical activation of fibrinolysis in atherosclerotic disease detected by B beta 15-42 assay

Plasma B beta 15-42 and fibrinopeptide A (FPA) concentrations, which are respectively indicators of plasmin and thrombin in vivo activity, were measured in 46 patients with ischemic arterial disease without signs of acute thrombosis. In the group as a whole, an increase in both B beta 15-42 and FPA was found. When the patients were divided in two groups on the basis of their reversible (transitory ischemic attacks and unstable angina) or irreversible (stroke and myocardial infarction) ischemic episodes, the levels of B beta 15-42 were significantly elevated only in the former group when compared to controls (p less than 0.01). In the latter group we found significantly increased levels of FPA with respect to both controls (p less than 0.01) and patients with reversible and transient ischemic episodes (p less than 0.05). Moreover, the B beta 15-42/FPA ratio was significantly lower in patients with irreversible ischemic episodes than in controls (p less than 0.01) and patients with transient ischemic episodes (p less than 0.01), while no difference was found between the latter group and controls, although FPA and B beta 15-42 were significantly higher. These results suggest that in patients with transient and reversible ischemic episodes fibrinolytic activity is able to counterbalance an increased thrombin activity, while this does not appear to occur in patients with irreversible ischemic episodes.

Evidence for a relationship between high fibrinogen levels and decreased thrombin activity in vivo in elderly subjects

In order to investigate whether high fibrinogen levels were associated with elevated thrombin activity, we measured fibrinogen and fibrinopeptide A in 37 elderly healthy subjects ranging from 60 to 93 years. Fibrinogen levels (519.1 +/- 127.0 mg/dl) and fibrinopeptide A (5.9, 0.9-18.1 ng/ml) were significantly higher than in younger controls. A highly significant negative linear correlation was found between fibrinogen and fibrinopeptide A in the elderly subjects (p less than 0.01). However, a polynomial regression showed that this negative relationship was present at the fibrinogen levels ranging between 420 and 700 mg/dl. Our results suggest that high fibrinogen levels in elderly subjects do not necessarily mean that their thrombin activity is concomitantly increased.

Thrombin activity and oral anticoagulant therapy: a preliminary study

The aim of this work was to investigate whether the thrombin activity is related to the degree of anticoagulation induced by oral anticoagulants. Moreover, we tried to detect an optimal anticoagulation range at which the lowest possible thrombin activity can be reached. We investigated 28 patients (19 women and 9 men, mean age 54 +/- 9 years). Anticoagulation had been induced by acenocoumarol for at least 1 year before the beginning of this study. The degree of anticoagulation was monitored by the thrombotest coagulation method. The therapeutic range was 5-13%. The thrombin activity was measured by means of the fibrinopeptide A radioimmunological assay. In 15, 7, and 6 of the patients, thrombotest and fibrinopeptide A were carried out twice, once, and three times, respectively. Our results show first of all a significant positive relationship between thrombotest and fibrinopeptide A (p less than 0.001). Once this result was obtained, we tried to improve our identification of the behaviour of the thrombin activity in relation to the degree of anticoagulation assessed by thrombotest. For this purpose we employed a third-degree polynomial regression analysis which showed a better fit of the data. Since the curve became steeper from about 10% thrombotest levels, we divided the FPA values on the basis of thrombotest ranges. FPA values for the 14- to 25% thrombotest range were significantly different from those in the thrombotest range of 4-10%. Moreover, FPA levels in the 11 to 13% thrombotest range were significantly different from those in the thrombotest range of 4-10%. Our results suggest that a significant decrease in thrombin activity may be achieved only with a deep anticoagulation.

Fibrinogen and fibrinolytic activity in hyperthyroidism before and after antithyroid treatment

Plasma concentration of fibrinogen and B beta 15-42, a specific product of fibrinogen metabolism induced by plasmin, were measured in a group of patients with untreated hyperthyroidism and in controls. Significantly increased plasma levels of both parameters were observed in hyperthyroid patients. The restoration of euthyroidism either by antithyroid drug or by radioiodine caused a significant decrease of fibrinogen and B beta 15-42. These data indicate that hyperthyroidism is another clinical condition associated with increased concentration of fibrinogen and B beta 15-42.

Fibrinopeptide A and B beta 15-42 in liver cirrhosis

In order to detect even minimal fibrinolysis activation in liver cirrhosis, we measured fibrinopeptide B beta 15-42 (B beta 15-42), an indicator of plasmin activity in vivo and alpha 2-antiplasmin (alpha 2-AP) in a group of cirrhotic patients. The second goal of this study was to investigate whether an increased fibrinolytic activity is related to a chronic disseminated intravascular coagulation. For this purpose we concomitantly measured fibrinopeptide A (FPA), marker of thrombin activity in vivo. Results show significantly higher levels of B beta 15-42 in cirrhotic patients than in control (p less than 0.01). In patients with high FPA levels we found significantly higher values than in patients with normal FPA (p less than 0.01). alpha 2-AP was lower in patients with high FPA levels than in patients with normal FPA (p less than 0.05). A significant negative correlation was found between FPA and alpha 2-AP only in patients with high FPA (p less than 0.05). There was no relationship between B beta 15-42 and FPA nor between B beta 15-42 and alpha 2-AP when all patients were considered. These findings confirm that in liver cirrhosis fibrinolysis activation may occur. The primary pathogenetic role of DIC may be important in this respect. However the lack of correlation between FPA and B beta 15-42 suggests that other pathogenetic factors may be involved in determining fibrinolysis activation.