Ambulatory sports in asthma improves physical fitness and reduces asthma-induced hospital stay

BACKGROUND: Prevention of posttransfusion non-A,non-B hepatitis in recipients of blood components improved considerably with the introduction of the second-generation of hepatitis C virus (HCV) antibody tests. In 1993, third-generation HCV antibody assays were introduced in Europe. STUDY DESIGN AND METHODS: The performance of three generations of anti-HCV enzyme-linked immunosorbent assay (ELISA) (ELISA-1, -2, -3) was compared in routine blood donor screening (99,394 donations were tested with ELISA-1, 167,999 donations with ELISA-2, and 262,090 donations with ELISA-3) and in serial samples from nine patients with documented acute posttransfusion HCV infection. RESULTS: Eight (0.01%) repeat donors, previously negative in ELISA-1, were found positive in ELISA-2 and were confirmed as positive in second-generation recombinant immunoblot assay and/or cDNA polymerase chain reaction. In the donor population, no difference in the sensitivity of ELISA-2 and -3 was observed. The specificity of the three generations of ELISAs was comparable (99.8, 99.7, and 99.7%). In seroconversion samples, ELISA-2 and -3 detected HCV antibodies at the same time in seven patients, but in two patients, ELISA-3 found HCV antibodies, respectively, 63 and 77 days earlier than ELISA-2 did. In the seroconversion samples, ELISA-2 and -3 were significantly more sensitive than second- and third-generation recombinant immunoblot assays. CONCLUSION: ELISA-3 did not detect more HCV-infected individuals in a donor population that previously tested negative in ELISA-2, but it did detect HCV antibodies earlier in some patients with acute HCV infection. ELISA-2 and -3 were significantly more sensitive than second- and third-generation recombinant immunoblot assays.     

Effect of natural antioxidants, superoxide dismutase and hydrogen peroxide on capacitation of frozen-thawed bull spermatozoa

This study comprised 100 persons with antibodies to hepatitis C virus (HCV), including 77 intravenous drug users (IVDUs). They were tested with serological HCV typing assays (Murex HCV serotyping 1-6 assay; Chiron RIBA HCV Serotyping SIA). Patients with a positive polymerase chain reaction (PCR) for HCV (n = 66) were tested with genotyping molecular assays (Inno-Lipa HCV II test; Sorin GEN-ETI-K HCV typing assay). Comparison of the results of these tests showed that (a) 92% of samples could be typed by one test at least; 44% could be typed by all four tests; 88% could be typed by one serological test at least and 66% by one molecular test at least; (b) 81% of the samples successfully tested with both serological tests gave comparable results; 95% of the samples successfully tested with both molecular tests gave comparable results; (c) when serological and molecular tests yielded different results, sequences in the 5'-non-coding (5' NC) or E1 regions always confirmed the results of the molecular tests; (d) in case of discrepancy between the results of the molecular tests the E1 region sequences confirmed the Sorin test results. It is concluded that the molecular tests compared gave similar results. The fact that the Murex serological test gave comparable results in more than 80% of cases indicates that it is an alternative to the molecular tests for routine diagnosis. However, comparison of the results of this test with those obtained in patients consulting a hepatology department showed that it gave the best results in a population of patients not exposed repeatedly to HCV.     

Multivariate analysis of risk factors for hepatocellular carcinoma in patients with hepatitis C virus-related liver cirrhosis

To elucidate the risk factors for hepatocellular carcinoma (HCC) in hepatitis C virus (HCV)-related liver cirrhosis (LC), we examined 204 cirrhotic patients negative for hepatitis B surface antigen and positive for HCV antibodies. The independent influence of various clinical characteristics in these patients was analyzed by multiple logistic regression, and the risk factors for HCC were identified. Multiple logistic regression analysis identified and ranked the following four risk factors: male sex (P < 0.001), habitual heavy drinking (P < 0.005), hepatitis B virus antibody positivity (anti-HBs and/or anti-HBc, P < 0.05), and age greater than 60 years (P < 0.05). The odds ratio of HCC was 4.20 (95% confidence interval; CI, 1.80-9.78) in male patients, 3.27 (95% CI, 1.46-7.30) in habitual heavy drinkers, 2.01 (95% CI, 1.01-3.99) in patients positive for hepatitis B virus antibodies, and 2.06 (95% CI, 1.00-4.23) in patients older than 60 years. The cumulative occurrence rates of HCC after blood transfusion were significantly higher in habitual heavy drinkers (4.8%, 49.4%, and 74.7% at 10, 20, and 30 years, respectively) than in non-drinkers (0%, 21.0%, and 23.3% at 10, 20, and 30 years, respectively, P < 0.0003). The mean interval for progression to LC after blood transfusion was significantly shorter in the habitual heavy drinkers than in the non-drinkers (22.4 +/- 4.4 years vs 28.4 +/- 3.9 years; P < 0.0003). This multivariate analysis revealed that habitual heavy drinking and hepatitis B virus antibody positivity are significant risk factors for HCC in HCV-related liver cirrhosis.     

Patterns of sexual and injecting risk behaviours in French intravenous drug users not reporting HIV and hepatitis C virus seropositivities

AIMS: To characterize and identify determinants of risk behaviour patterns of intravenous drug users (IDUs) independently of changes due to knowledge of HIV or hepatitis C Virus (HCV) seropositivity. DESIGN: A cross-sectional survey using a structured questionnaire concerning sexual, injecting and HIV and HCV antibody testing practices. SETTING: IDUs were interviewed in the Paris region at 10 treatment or psychosocial centres. PARTICIPANTS: Six hundred and twelve consecutive sexually active IDUs over 18 years able to answer the questionnaire. MEASUREMENTS: Five hundred and ninety-five IDUs completed the questionnaire. The risk-behaviour patterns of the 328 IDUs not reporting HIV or HCV seropositivity were analysed by phi correlation. Risk factors for each risk behaviour were determined by regression logistic models yielding odds ratios (OR) and their 95% confidence intervals (95% CI). FINDINGS: Several risk behaviour patterns were suggested: (1) lending, borrowing; (2) not or inconsistently testing HIV and HCV serology and not or inconsistently using condoms; (3) having multiple partners and prostitution; and (4) not using clean equipment. Alcohol abuse was independently and specifically associated with lending (OR = 3.8; 95% CI: 2.1-7.0) and borrowing (OR = 3.3; 95% CI: 1.8-6.1); homelessness with injecting risk behaviours and with prostitution (OR = 2.7; 95% CI: 1.2-6.1); low educational level and having children with not or inconsistently using condom and serology testing; and cocaine use with not or inconsistently using condoms (OR = 0.4; 95% CI: 0.3-0.7) and serology testing and not using clean equipment (OR = 0.4; 95% CI: 0.2-0.8). Having multiple partners and prostitution had no common risk factors. CONCLUSIONS: Identifying specific risk factors could help to target drug harm reduction programmes for each risk behaviour pattern among IDUs not reporting HIV and HCV seropositivity.     

High prevalence of serum cryoglobulins in multitransfused hemophilic patients with chronic hepatitis C

The prevalence, clinical relevance, and risk factors of serum cryoglobulins in hemophilic patients with chronic hepatitis C virus (HCV) infection are unknown. We studied 135 consecutive hemophilic patients (median age, 31 years; range, 10 to 69 years) with chronic hepatitis C, exposed to the virus for 10 to 41 years. A total of 67 patients were coinfected with the human immunodeficiency virus (HIV), and 3 (2%) had signs of cirrhosis. Serum samples were tested for the presence of cryoglobulins, hepatitis B virus (HBV) markers, including HBV-DNA by hybridization assay, and antibody to HCV by enzyme immunoassay (EIA). Serum HCV-RNA was tested by polymerase chain reaction and typed with a hybridization technique. Samples were also tested for antitissue antibodies, immunoglobulins, rheumatoid factor, and C3 and C4 proteins of complement. Forty-two hemophiliacs (31%) circulated cryoglobulins (median levels, 166 mg/L; range, 66 to 480) predominantly type III (62%; and 29% type II). None of the patients had clinical signs or symptoms of systemic vasculitis. Cryoglobulinemic patients had more often serum HCV-RNA (95% v 80%, P < .05), rheumatoid factor (20% v 6%, P < .05), higher levels of IgG (2,354 +/- 682 mg/dL v 1,928 +/- 557 mg/dL, P < .0005) and IgM (323 +/- 226 mg/dL v 244 +/- 243 mg/dL, P < .05), and lower levels of serum C4 (19 +/- 8 mg/dL v 24 +/- 8 mg/dL, P < .05) than patients without cryoglobulins. The risk of producing cryoglobulins was greater for 114 patients circulating HCV-RNA than for 21 nonviremic patients (odds ratio [OR] = 4.9, 95% confidence interval [CI] = 1.1 to 22.0) and for the 31 patients with longer exposure to HCV (more than 26 years) than for the 24 patients with shorter (17 years or less) exposure (OR = 4.4 95% CI = 1.1 to 18.0). In conclusion a large number of multitransfused hemophiliacs with chronic HCV infection circulated serum cryoglobulins but none had clinical signs or symptoms of vasculitis. The risk of developing cryoglobulins parallels the duration of exposure to HCV.     

Lack of familial clustering of hepatitis C virus infection

BACKGROUND: Although transmission of hepatitis C virus (HCV) through parental exposure is well documented, it is still controversial whether familial clustering of HCV occurs. METHODS: To investigate risk factors for HCV infection, 109 cases and 84 non-infected controls were studied. In addition, 250 family members (104 men, 146 women) of cases and 170 family members of controls (64 men, 106 women) were tested for HCV infection using an anti-HCV antibody, alanine aminotransferase (ALT), and reverse transcribed polymerase chain reaction (RT-PCR). RESULTS: In the case-control analysis, people aged > or =60 were almost three times more likely to be infected by HCV than those aged <40. Risk of HCV infection was most strongly related to a history of blood transfusion (OR = 12.6, 95% CI: 4.3-36.5) followed by a history of jaundice (OR = 4.1, 95% CI: 1.3-12.6). Only one family member of cases and no-one related to the controls had HCV infection. CONCLUSIONS: These results suggest that, in Korea, age and parenteral exposure, such as a blood transfusion, are risk factors for HCV infection and familial clustering of HCV infection, if it occurs, is rare.     

Physical and psychological effects of anogenital warts on female patients

To evaluate whether hepatitis C virus (HCV) infection is an occupational hazard in the dental environment, serum samples collected in 1990-1991 from 461 dentists were tested for the antibody to HCV (anti-HCV) with first- and second-generation HCV enzyme-linked immunoassays (EIAs). Five of the 363 (1.38%) serum samples were reactive by the first-generation (C100-3) HCV EIA. Of the same 363 samples and the other 98 samples, 3 (0.65%) were reactive by the second-generation test. Of the 5 first-generation EIA reactive samples, only the 2 samples showing an absorbance of greater than 2.0 were also reactive to the second-generation EIA. The other 3 low-absorbance samples became negative and were regarded as false positives. Among the 358 samples negative by the first-generation EIA, 1 was reacted by the second-generation EIA. Those samples positive by the first- and/or second-generation HCV EIA were analyzed further by cDNA/polymerase chain reaction (PCR) to detect the presence of HCV RNA. Only 1 of the 5 first-generation EIA reactive samples was positive by PCR, but 2 of the 3 second-generation EIA reactive samples were PCR positive. These results are comparable to the anti-HCV prevalence of healthy blood donors (0.95% by C100-3 assay) and pregnant women (0.63% by recombinant immunoblot assay). We conclude that the prevalence of HCV infection among dentists in Taiwan is low, and there is no increased risk of HCV infection through the practice of dentistry, at least in our area.     

Demographic determinants of hepatitis C virus seroprevalence among blood donors

OBJECTIVE: To measure demographic determinants of hepatitis C virus (HCV) seroprevalence among blood donors in the United States. DESIGN: Cross-sectional epidemiological study. SETTING: Five blood centers in different regions of the United States. SUBJECTS: A total of 862,398 consecutive volunteer blood donors with one or more nonautologous donations from March 1992 through December 1993. METHODS: Demographic data collection, serological screening with second-generation anti-HCV enzyme immunoassay, and confirmation with anti-HCV recombinant immunoblot. RESULTS: There were 3126 donors with at least one blood donation confirmed HCV-seropositive, for a crude prevalence of 3.6 per 1000. Age-specific HCV seroprevalence rose from 0.5 per 1000 donors younger than 20 years to a maximum of 6.9 per 1000 in donors aged 30 to 39 years and declined in older age groups. There was interaction between age and educational attainment, with 30- to 49-year-olds with less than a high school diploma at highest risk of HCV infection (odds ratio [OR], 33.0; 95% confidence interval [CI], 23.0 to 47.2 compared with those younger than 30 years with a bachelor's degree or higher degree). Other independent risk factors for HCV seropositivity included male sex (OR, 1.9; 95% CI, 1.8 to 2.1), black race (OR, 1.7; 95% CI, 1.6 to 1.9), Hispanic ethnicity (OR, 1.3; 95% CI, 1.1 to 1.5), previous blood transfusion (OR, 2.8; 95% CI, 2.5 to 3.1), and first/only time donor status (OR, 4.2; 95% CI, 3.9 to 4.5 compared with repeat donors). Seropositivity for human T-lymphotropic virus types I and II, human immunodeficiency virus, or hepatitis B core antigen was highly associated with HCV seropositivity (OR, 10.4; 95% CI, 9.6 to 11.4 for one vs no marker). CONCLUSIONS: Despite a low overall HCV prevalence in blood donors in the United States, there is a marked variation in HCV seroprevalence by demographic subgroup, even after controlling for prior blood transfusion, a recognized risk factor for HCV. Further study of the prevalence of other parenteral risk factors such as past injection drug use among blood donors is needed.     

Molecular epidemiology of HIV-1 infection in the Philippines, 1985 to 1997: transmission of subtypes B and E and potential emergence of subtypes C and F

OBJECTIVES: to identify the risk factors for hepatitis B (HBV) and hepatitis C (HCV) virus infections in drug users attending two drug treatment centres in Northwest England, and to evaluate the effect of both needle exchange and hepatitis B vaccination on the prevalence of hepatitis B and hepatitis C infections. METHODS: a retrospective, cross-sectional study performed at the Regional Infectious Disease Unit and a Primary Care Centre for drug users in Liverpool. The study population included 773 drug users who had hepatitis serology performed between January 1992 and April 1996. Information on risk factors was obtained from clinical records; hepatitis serology data were obtained from the Liverpool Public Health Laboratory database. RESULTS: the overall seroprevalences of exposure markers for HBV (anti-HBc antibody) and HCV (anti-HCV antibody) were 48% and 67%, respectively. Duration of injecting drug use was the strongest predictor of HCV infection, with a crude odds ratio of 8.9 (95% confidence interval (CI): 4.5-17) for >10 compared to <3 years of injecting, and was also a strong predictor of HBV infection, with an adjusted odds ratio (controlled for the effects of HBV vaccination) of 5.7 (95% CI: 3.2-10) for >10 compared to <3 years' injecting. Vaccination against HBV was associated with greatly reduced HBV seroprevalence (crude odds ratio 0.11, 95% CI: 0.06-0.18). Overall, HCV was acquired earlier in the injecting career than HBV, but drug users who were not vaccinated against HBV acquired markers for HBV even more rapidly than for HCV. We found no independent protective effect for either anti-HBc or anti-HCV acquisition after the introduction of a needle-exchange scheme. CONCLUSIONS: hepatitis C is highly prevalent among Merseyside drug users and is likely to prove difficult to control because of rapid acquisition early in the injecting career. Vaccination against hepatitis B is the best means of protecting drug users from hepatitis B, and should be offered before injecting is commenced.     

Effect of protein malnutrition on the glycolytic and glutaminolytic enzyme activity of rat thymus and mesenteric lymph nodes

Genotyping of hepatitis C virus (HCV) of liver disease patients in the Dominican Republic was performed. Eighty-four samples positive for HCV antibody, which were confirmed by ELISA, particle agglutination, and recombinant immunoblot assay III tests, were subjected to HCV genotyping by polymerase chain reaction using type-specific primers located in the nonstructural protein 5 region. Of the 84 samples tested, 50 (59%) were found to have genotype 1a/I and this genotype was the most frequent type detected in the present study. The numbers of isolates of genotypes 1b/II, 2a/III, 2b/IV, and 3a/V were three (3.6%) six (7.1%), two (2.4%), and two 2.4%), respectively. The number of samples having mixed genotype populations was 16 (19%). The possible causes of the high prevalence of genotype 1a/I in the Dominican Republic compared with other countries and of the high detection ratio of samples having mixed genotypes are discussed.     

Usefulness of combined color Doppler/contrast in providing complete delineation of left ventricular cavity

Although detection of disease-induced hepatitis A virus (HAV)-specific antibodies in saliva has been successfully utilized in a few epidemiological studies, available assays fail to detect lower salivary anti-HAV levels associated with vaccine-induced immunity. We present a new capture enzyme immunoassay which employs a three-layer antibody recognition system. Evaluation of paired saliva-serum specimens from 1,025 international travellers, 134 other volunteers, and 91 hepatitis A vaccine recipients demonstrated 99.6% (95% confidence interval, 98.4 to 99.9) specificity and 98.7% (95% confidence interval, 97.7 to 99.4) sensitivity of this salivary assay in differentiating between immune and susceptible individuals, compared with serum-based methods. We conclude that this assay is sufficiently sensitive for reliable detection of both vaccine- and infection-induced HAV-specific immunoglobulin G in saliva, even when corresponding anti-HAV levels in serum are very low (< 1 IU/ml).     

Bicelles: a model membrane system for all seasons?

OBJECTIVES: To establish population-based HIV survey data in selected populations, and to assess the validity of extrapolation from HIV sentinel surveillance amongst antenatal clinic attenders (ANC) to the general population. METHODS: In a population survey, adults aged > or = 15 years were selected by stratified random cluster sampling (n = 4195). The survey was carried out in catchment populations of clinics used for national HIV surveillance. The methodology allows detailed comparisons of HIV infection patterns to be made in two areas (urban and rural). Whereas the sentinel surveillance used serum-based HIV testing, the population survey used saliva (93.5% consented to provide a saliva sample). RESULTS: Surveillance of ANC tended to underestimate the overall HIV prevalence of the general population, but differences were not statistically significant. In the urban area, the adjusted overall HIV prevalence rate of ANC (aged 15-39 years) was 24.4% [95% confidence interval (CI), 20.9-28.0] compared with 26.0% (95% CI, 23.4-28.6) in the general population. The respective rural estimates were 12.5% (95% CI, 9.3-15.6) versus 16.4% (95% CI, 12.1-20.6). Age-specific prevalence rates showed ANC to overestimate infection in teenagers (aged 15-19 years), whereas in the reverse direction of those aged > or = 30 years. Teenagers analysed by single year of age revealed both ANC and women in the general population with about the same steep increase in prevalence by age, but the former at consistently higher rates. Extrapolations might be biased substantially due to the higher pregnancy rates amongst uninfected individuals. CONCLUSIONS: ANC-based data might draw a rather distorted picture of current dynamics of the HIV epidemic. Even though representing an obvious oversimplification, extrapolations of overall prevalence rates may correlate with that of the general population.     

Is low selenium status a risk factor for lung cancer?

The hypothesis that low selenium may in some circumstances be a risk factor for lung cancer was investigated in a case-control study nested within a longitudinal study. Serum samples from 9,101 cancer-free individuals were collected and stored at -20 degrees C by the Finnish Mobile Clinic in 1968-1971 and 1973-1976. During follow-up until the end of 1991, 95 cases of lung cancer were diagnosed. Selenium concentrations were determined from the serum samples of the cases and 190 controls, individually matched for sex, age, and place of residence. Mean levels of serum selenium in cases and controls were 53.2 microg/liter and 57.8 microg/liter, respectively. The relative risk of lung cancer between the highest and lowest tertiles of serum selenium, adjusted for smoking, serum alpha-tocopherol, serum cholesterol, serum copper, serum orosomucoid, and body mass index (kg/m2), was 0.41 (95% confidence interval (CI) 0.17-0.94). The association was stronger at lower levels (<5.9 mg/liter) of alpha-tocopherol (relative risk=0.24, 95% CI 0.07-0.85). The association was also pronounced among current smokers and at higher levels of serum orosomucoid and serum copper. The relative risk for smokers who were twice ranked in higher selenium tertiles, at an interval of 4-7 years, in comparison with smokers who remained in the lowest tertile was 0.16 (95% CI 0.04-0.74). In accordance with the hypothesis, the findings suggest that very low selenium status may contribute to the risk of lung cancer.     

Causes of death in Canadians with haemophilia 1980-1995. Association of Hemophilia Clinic Directors of Canada

The life expectancy of individuals with haemophilia was close to that of the general population in the early 1980s. Since then, life expectancy has decreased, due to transfusion-transmitted virus infections. Deaths in individuals with haemophilia were investigated by analysing 2450 records from the Canadian Hemophilia Registry, for the years 1980-1995. Deaths were tabulated by age, year and cause, and compared with that of the Canadian male population by calculating standardized mortality ratios (SMRs). The median life expectancy at 1 year of age was calculated for various subpopulations and the impact of various population characteristics was assessed by survival regression modelling. There were 359 deaths and the annual number of deaths increased significantly after 1986. Risk factors were seropositivity to human immunodeficiency virus (relative risk 16.7, 95% CI 11.1-25.1), severe haemophilia (1.9, 1.3-2.7) and moderate haemophilia (1.8, 1.2-2.6). In HIV antibody negative individuals, the overall death rate was not increased (SMR 0.9, 95% CI 0.7-1.1) and only haemorrhage was significantly increased. In HIV antibody positive individuals, causes of death which were significantly increased were acquired immunodeficiency syndrome, liver failure, haemorrhage, lymphoma, liver cancer, nonspecific infections, and trauma or violence. Deaths due to the acquired immunodeficiency syndrome accounted for only 66% of the excess deaths in individuals who were HIV antibody positive. Life expectancy has markedly decreased since the onset of the HIV epidemic. The impact of HIV is underestimated by considering only deaths due to the acquired immunodeficiency syndrome; other HIV-linked causes need also to be considered.     

Immunologic events during the incubation period of hepatitis C virus infection: the role of antibodies to E2 glycoprotein. Multicentre Hemodialysis Cohort Study on Viral Hepatitis

BACKGROUND: The study of the sensitivity of screening assays is greatly facilitated by testing the sequential changes in seroconverting individuals. The aim of this study was to investigate the early immunologic response after hepatitis C virus (HCV) infection and to evaluate whether HCV envelope (E2) recombinant antigen would provide a significant increase in sensitivity for detection of anti-HCV. STUDY DESIGN AND METHODS: Twenty hemodialysis patients who were seroconverting to anti-HCV were included in this study. They were followed up for a mean period (+/- SD) of 10.5 +/- 3.3 months, in which 13 to 46 serum samples per case were collected. Each sample was tested for anti-HCV by second- and third-generation enzyme immunoassay (EIA-2 and EIA-3) and recombinant immunoblot assay (RIBA-3). E2 antibodies were tested by a prototype EIA in which E2 was expressed as a recombinant antigen in Chinese hamster ovary cells. RESULTS: Alanine aminotransferase elevation was observed in 18 of 20 cases. Reactivity against c100, c33c, c22, NS5, and E2 was detected in 15 (75%), 19 (95%), 15 (75%), 2 (10%), and 17 (85%) patients, respectively; c33c was the most immunogenic antigen, followed in descending order by E2, c22, c100, and NS5. E2 antibody reactivity resolved the two RIBA-3-indeterminate cases. However, there was no case in which E2 reactivity preceded all other HCV antigens. Anti-E2 was found to react in all patients of genotypes 1a, 1b, and 3a but in only 2 of 4 patients of genotype 4a. CONCLUSION: In this group of seroconverting individuals, E2 antigen was shown to be highly immunoreactive and did resolve some RIBA-3-indeterminate samples as being positive, on the basis of reactivity to multiple antigens, but it did not improve early detection of seroconversion.     

The effect of antibody to Streptococcus mutans in saliva on caries activity and S. mutans adhering

An indirect enzyme-linked immunosorbent assay (ELISA) was used for measuring IgA antibody to whole cell of Streptococcus mutans (serotype c) in saliva. 36 parotid salivary samples of human were collected from two groups: Caries free (CF) and caries sensitive (CS). The result shows that the IgA antibody to S. mutans in CF group was higher than those in CS group (P < 0.05). The saliva antibody was gained from the rabbits by injection with S. mutans (serotype c), and the adhesion of S. mutans--3H on the surface of hydroxylapatite beads treated by rabbit's saliva was measured. The results show that the saliva with immunity could inhibit the S. mutans to adhere on the HA beads (P < 0.05). It means saliva antibody may prevent caries through inhibition of S. mutans from adhesion.     

Total contact casts and removable cast walkers. Mitigation of plantar heel pressure

In this study we prospectively assessed the reliability of a new fibrin monomer assay in 106 outpatients with clinically suspected deep venous thrombosis of the lower limb. According to the results of the objective tests and using different cut-off points we calculated the sensitivity, specificity and negative predictive value of the fibrin monomer assay. The prevalence of deep vein thrombosis was 44.3% (31.1% proximal, 13.2% distal). Using a cut-off level of plasma fibrin monomer of 3.5 microg/ml, a sensitivity, specificity and negative predictive value of 100% (95% CI: 94-100%), 35.6% (95% CI: 23-48%) and 100% (95% CI: 86-100%), respectively, were obtained. The exclusion rate was 19.8% (95% CI: 12-27%) of all referred patients. These accuracy indices compared favourably with the respective results of a routine D-dimer ELISA used for comparison. Conclusion: This new fibrin monomer assay appears to be a reliable method for the exclusion of deep vein thrombosis in symptomatic outpatients.     

Epidemiology of hepatitis C and G in sporadic and familial porphyria cutanea tarda

From 1995 to 1997, we prospectively evaluated the prevalence of hepatitis C virus (HCV) RNA in 124 patients with porphyria cutanea tarda (PCT) from Northern France (83 sporadic and 41 familial PCT). Serum samples were analyzed for ferritin, transaminases, HCV antibodies, and HCV RNA. In addition, genotyping of HCV and searches for HCV infection risk factors (blood transfusion, iv drug abuse, and surgical intervention) were performed. Twenty-six of 124 patients (21%; 95% CI: 13.9-28) were positive for serum HCV antibodies. All of them were also positive for HCV RNA. The prevalence of HCV infection was higher in the sporadic PCT group (26.5%, 22 out of 83) than in the familial PCT group (9.7%, 4 out of 41). Risk factors for hepatitis C infection were found to be significantly increased in the HCV-positive group when compared with the HCV-negative PCT group. In all HCV-positive patients with a risk factor, the suspected date of exposure to the virus always preceded the clinical onset of PCT. The HCV genotype pattern in PCT patients was similar to that observed in nonporphyric HCV patients in western European countries. Serum ferritin level was increased in both HCV-positive and HCV-negative porphyric patients. Transaminase levels were significantly higher in HCV-infected PCT patients. Sixty-seven out of 124 patients were retrospectively studied for hepatitis G virus (HGV) infection. Six of these 67 patients (8.9%; 95% CI: 2.1-15.8) were positive for HGV RNA. None of the six HGV-infected patients were positive for HCV RNA. The HGV-infected patients did not differ statistically from those without HGV infection with regard to age, ferritin, transaminase levels, and PCT treatment. These results support the view that sporadic cases of HGV infection may occur frequently. This study of a large cohort of HCV and PCT patients further documents an increasing gradient in HCV prevalence from northern to southern Europe, and shows that HCV infection acts as a triggering factor of PCT. Finally, the HGV prevalence found in the PCT patients was comparable with that found in French blood donors, suggesting that HGV is not a PCT triggering factor.