Saturday Poster Sessions, October 28, 2006

HCV: Diagnosis and Natural History

 

# 211: Influence of Cannabis Use on Severity of Hepatitis C Disease

J. H. Ishida; C. Jin; P. Bacchetti; V. Tan; M. G. Peters; N. A. Terrault

 

Background:

Complications of hepatitis C virus (HCV) infection are primarily related to the development of advanced fibrosis. Risk factors for fibrosis include male gender, older age at HCV infection and heavy alcohol use, but the role of cannabis remains controversial.

 

Objective:

To study the association between cannabis use and fibrosis severity in persons with chronic HCV infection.

 

Methods:

Between 2001 and 2004, 328 HCV-infected subjects enrolled from university and community sources underwent in-person interviews (to assess demographics, risk factors for HCV, and use of cannabis and alcohol), virologic testing and liver biopsy. Biopsies were scored for fibrosis using the Ishak method (scale F0 to F6) by a single pathologist blinded to clinical data. Biopsy adequacy was assessed by length and number of portal tracts.  204 completed all the baseline requirements.  Included and excluded subjects were not significantly different except that the former used cannabis more frequently than the later group.

 

Results:

The median age of the cohort was 46.8 years, 69% were male, 49% were Caucasian, 61% earned ≤$15,000 per year, and the presumed route of infection was intravenous drug use in 70%.  Ninety-seven percent had at least one drink witin year prior to enrolment.  Current (within 12 months of enrollment) cannabis daily use frequency was daily (14%), used cannabis within the year prior to enrolment (20%). Fibrosis stage median was 1 (scale 0-6), necoinflammation median was 5.

 

Daily cannabis use was associated with moderate to severe fibrosis compared to mild fibrosis in univariate analysis.  Gender, race, enrollment age, HCV duration and infection source, HCV genotype, HIV, daily tobacco use, and lifetime alcohol use were not significantly associated with mild fibrosis or moderate to severe fibrosis stage in univariate and multivariate analysis. 

 

Conclusion:

·        Current daily cannabis use independently increased the odds of moderate to severe fibrosis by nearly 7-fold in persons with chronic HCV infection.

o       The duration of lifetime moderate to heavy alcohol use was also independent predictor of moderate to severe fibrosis

·        There was no association between current daily cannabis use and mild fibrosis.

o       HCV viral load was an independent predictor of mild fibrosis.

·        The number of portal tracts was associated with both mild and moderate to severe fibrosis, highlighting the importance of controlling for biopsy adequacy.

·        This cross-sectional design limits the ability to establish a temporal relationship between cannabis use and fibrosis stage.

·        Quantity, duration or method of cannabis use were not assessed in detail.

·        Our results indicate that HCV-infected individuals should be counseled to reduce or abstain from cannabis use.

 

Future Directions:

·        Confirm differential effect of cannabis use by severity of disease.

·        Prospective cohort study of cannabis versus non-cannabis users with chronic HCV using more detailed cannabis assessments.


# 212: Independent evaluation of 4 blood scores of liver fibrosis in chronic hepatitis C: FibroMeter, Fibrotest, Hepascore and APRI

P. Halfon; Y. Bacq; A. De Muret; G. Pénaranda; M. Bourlière; D. Ouzan; A. Tran; D. Botta-Fridlund; C. Renou; M. Brechot; C. Degott; V. Paradis

 

Introduction:

 

Several blood scores of liver fibrosis have been published. The most validated scores are the Fibrotest (FT) and APRI. However, possibly more accurate tests have been recently published: Fibrometer (FM) and Hepascore (HS). The aim of this study was to compare the diagnostic accuracy of those 4 tests in independent conditions and populations.

 

Methods:

356 patients with chronic viral hepatitis C from 2 different French areas with a liver specimen length ≥ 15 mm (22 ± 7 mm) were included. Liver specimens were evaluated by 2 independent pathologists according to the Metavir staging before reaching a consensus. Blood variables were determined on fresh or frozen blood samples.

 

Results:

The distribution of Metavir stages according to liver specimens was: F0: 4%, F1: 55%, F2: 26%, F3: 11%, F4: 4%. The AUROC are listed as a function of blood score and fibrosis cut-off in the Table 1.

 

The AUROC of those 4 blood scores were not significantly different in that population characterized by a high proportion of F1 and a low proportion of F4. On the other hand, those scores had different patterns. Therefore, we evaluated the rate of misclassified patients (%) as a function of F stages or cut-off, FT vs FM respectively in the following Table 2.

 

The comparison of misclassification (blood vs liver) rates indicated significantly different patterns, FT vs FM respectively: F0+1: 18 vs 28 % (p=0.002), ≥F2: 43 vs 31 % (p=0.005), ≥ F3: 28 vs 12 % (p=0.065), F4: 15 vs 0 % (p: NA).

 

Conclusions:

These results show that the accuracy of those tests is sensitive to the fibrosis stage prevalence which depends on the population studied. For the diagnosis of clinically significant fibrosis (F≥2), those 4 blood scores had a similar performance in this population that lies in the lower range of published results. However, those tests have performance profiles significantly different as a function of fibrosis stages or cut-off. This has to be taken into account during the interpretation process. Moreover, the diagnostic target (fibrosis cut-off) has to be clearly defined.

 

Table 1

AUROC

FT

FM

APRI

HS

P

≥ F2

0.79

0.78

0.76

0.76

NS

≥ F3

0.81

0.85

0.81

0.81

NS

F4

0.86

0.94

0.92

0.89

NS

 

Table 2

%

F0

F1

F2

F3

F4

FT

0

19

52

29

15

FM

0

30

41

16

0

 

#213. Hepatitis virus C RNA quantification by automated Cobas AmpliPrep-Cobas TaqMan 48 (CAP-CTM) real-time PCR assay: an evaluation of performance.

S. Chevaliez; M. Bouvier-Alias; G. Dameron; F. Darthuy; J. Remire; J. Pawlotsky

Introduction:

 

Accurate, sensitive and specific HCV RNA quantification is mandated to monitor the virological responses and individually tailor pegylated interferon-ribavirin combination therapy. Real-time PCR quantification is likely to become standard technology for HCV RNA quantification. The Cobas AmpliPrep-Cobas TaqMan48 (CAP-CTM48) real-time PCR platform (Roche Molecular Systems) provides almost fully automated real-time PCR quantification of HCV RNA.

 

Objective: 

The objective of this study was to assess the intrinsic performance of the CAP-CTM48 real-time PCR platform for HCV RNA detection and quantification.

 

Methods:

Analytical sensitivity, precision and reproducibility were assessed by testing serial dilutions of a standard containing 5x106 HCV RNA IU/ml three times in different experiments. The lower limit of detection was studied by testing serial dilutions of a standard containing 50 HCV RNA IU/ml. Specificity was assessed by testing 200 anti-HCV antibody-negative samples. Quantification of the different HCV genotypes was studied by testing 123 clinical samples (genotype 1, n=29; 2, n=27; 3, n=28; 4, n=30; 5, n=9; and 6, n=2) neat and after serial dilutions in comparison with third-generation bDNA (Versant HCV RNA 3.0, Bayer HealthCare).

 

Results: 

(i) Testing serial dilutions of a standard containing 5x106 HCV RNA IU/ml showed linear quantification over the full range of HCV RNA levels and a strong correlation with the expected values (slope: 0.9671, R=0.9981). (ii) The coefficient of variations of triplicate testing ranged from 0.2% to 7.2% (1.9% on average). (iii) Specificity was 100%. (iv) HCV RNA was detected in 8 repeat samples from 50 IU/ml down to 22 IU/ml, in 6/8 samples at the 15 IU/ml concentration, 4/8 samples at the 10 IU/ml concentration and 5/8 samples at the 7 IU/ml concentration. (v) Serial dilutions of genotype 1 to 6 clinical samples showed HCV RNA levels in IU/ml generally higher in CAP-CTM48 than in bDNA (difference of the order of 0.7 log on average) when neat samples were tested, but the difference was reduced after the first dilution. (vi) Quantification of clinical samples was linear over the full range of tested values whatever the HCV genotype. (vii) A few genotype 2 and 4 samples were underquantified in the CAP-CTM48 assay relative to bDNA. Full-length sequence analysis of the 5’UTR showed potential mismatch positions that could explain these differences.

 

Conclusion:

CAP-CTM48 real-time PCR has good intrinsic performance, but two issues remain: a global overestimation of HCV RNA levels in IU/ml relative to bDNA in neat (but not diluted) samples, and occasional underquantification of genotype 4 and, sometimes, genotype 2 samples.


#214. Liver stiffness cut-off values in HCV patients: validation and comparison in an independent population.

M. Ziol; P. Marcellin; C. Douvin; V. de Ledinghen; R. Poupon; M. Beaugrand

 

Background:

Liver stiffness measurement (LSM) has been proposed as a noninvasive tool to assess liver fibrosis in patients with chronic hepatitis C. Several publications(1-3) have presented diagnosis accuracies and cut-off values for the diagnosis of significant fibrosis and cirrhosis but with different cut-off values. The aim of this study was to validate the diagnosis accuracy and cut-off values of LSM in an independent HCV population.

 

Method:

We prospectively enrolled 639 HCV patients in five French centers (Clichy: 178; Bondy: 163; Creteil: 129; Pessac: 101; Paris: 68). Within six month each of them had a liver biopsy (LB) and LSM. Fibrosis stage and activity grade were assessed using the METAVIR scoring system. Steatosis was scored as follows: S0: no; S1:1-10%; S2:11-30% and S3 more than 30%. ROC analyses were performed and cut-off values chosen to maximize the sum of sensitivity and specificity.

 

Results:

Eighty-six (13%) LB were considered unsuitable for fibrosis assessment (less than 1cm and/or 10 portal tracts if no obvious cirrhosis) and 59 (9%) of LSM unreliable (less than 8 valid measurements or IQR/median>50%). Analysis was conducted in 494 patients (319 men; age: 49 ± 12 years; BMI 25 ± 4 kg/m2). Patients' distribution was: F0=30; F1=193; F2=155; F3=47; F4=69. LSM was significantly (p<0.001) correlated to fibrosis stage (Spearman: 0.70), activity (0.45) and steatosis (0.35) but in multivariate analysis LSM was correlated to fibrosis only (partial correlation coefficient: 0.57).AUROC (95%CI) were 0.84 (0.80-0.87), 0.93 (0.90-0.95) and 0.96 (0.94-0.98) for F≥2, F≥3 and F=4 respectively. Optimal cut-off values for this population and those previously published applied to this same population are presented in the Table.

 

Conclusion:

These results obtained in an independent HCV population confirmed those previously published. Optimal cut-off values are slightly different but their performances are very close. This emphasizes the fact that cut-off values depend on the chosen balance between sensitivity and specificity. Finally, LSM appears as an accurate noninvasive method to assess liver fibrosis in HCV patients.

1. Ziol Hepatology 2005:48-54.

2. Castera Gastroenterology 2005: 343-50.

3. Coco AASLD 2005.

 

 

Cut-off values (kPa)

Sensitivity

Specificity

VPP

VPN

Diagnosis accuracy

F01 / F2,3,4

7.5

67

87

86

68

76

F01 / F2,3,4

8.7 (1)

59

92

90

65

74

F01 / F2,3,4

7.1 (2)

71

81

82

70

76

F01 / F2,3,4

8.3 (3)

61

89

87

65

74

F01,2,3 / F4

10.2

99

85

51

100

87

F01,2,3 / F4

14.5 (1)

80

94

69

97

92

F01,2,3 / F4

12.5 (2)

84

93

65

97

92

F01,2,3 / F4

14.0 (3)

81

94

68

97

92

 

 

#215. Independent Assessment of Non Invasive Liver Fibrosis Biomarkers in HIV-HCV Co-infected Patients: the Fibrovic Study.

P. Cacoub; F. Carrat; P. Bedossa; J. Lambert; G. Pénaranda; C. Perronne; S. Pol; P. Halfon

Introduction:

Many non invasive liver fibrosis scores have been proposed as alternatives to liver biopsy (LB) in HCV infected patients, i.e. Fibrotest (FT), APRI, Forns, Hepascore (HS) and Fibrometer (FM). FT, SHASTA, and Fib-4 scores have been tested in small cohorts of HIV-HCV co-infected patients.

 

Aim:

To compare diagnostic accuracies of FT, APRI, Forns, HS, FM, SHASTA, and Fib-4 in a large cohort of HIV-HCV co-infected patients.

 

Patients & Methods:

274 HIV-HCV coinfected patients, naïve of HCV treatment, had a LB before inclusion in the prospective ANRS HC02 Ribavic trial: 198 (72%) men, age 39.9 years, LB 18.5 mm, fibrosis stage (Metavir) of F1 in 68 (25%) patients, F2 in 110 (41%), F3 in 67 (23%), and F4 in 29 (11%). Diagnostic accuracies of each score were determined by area under the roc curve (AUROCs), and the accuracy (rate of well classified patient) compared to LB. AUROCs were compared with Hanley-McNeil test, and accuracies with McNemar or Chi2 test. Note that low values of AUROCs were expected, since our sample did not include patients with F0.

 

Results:

FT, HS, and FM were more accurate than other scores with AUROCs of 0.64 [95% CI 0.58 ;0.70], 0.69 [0.63 ;0.74], and 0.70 [0.61 ;0.73] for the diagnosis of significant fibrosis (F2F3F4), respectively. Values for the diagnosis of F3F4 were 0.72 [0.66 ;0.77], 0.76 [0.71 ;0.81], and 0.78 [0.73 ;0.83], respectively. For the diagnosis of cirrhosis (F4), AUROCs were 0.81 [0.76 ;0.85], 0.83 [0.78 ;0.88], and 0.84 [0.78 ;0.88]. Comparison of these 3 tests (Table) showed that for global analysis, accuracy FM > FT but not different from HS. In a stage by stage fibrosis analysis, accuracy FM > HS > FT except for F1 where FT > FM. Search for a better test by using combination of FT, HS and FM did not increase significantly the diagnostic performances of each test.

 

Conclusion:

In HIV-HCV co-infected patients, use of non invasive liver fibrosis biomarkers can correctly classify only patients with severe fibrosis (≥ F3, accuracies 74%-97%). For global analysis, accuracy of FM is higher than FT but similar to HS. In a stage by stage fibrosis analysis, FM is better for the diagnosis of ≥F2 and ≥F3 stages whereas FT is better for the diagnosis of F1.

 

 

Accuracy = rate of well classified patients (%)

Liver biopsy fibrosis (Metavir)

Global Analysis

F1

F2

≥F2

F3

≥F3

Number of patients

274

68

110

206

67

96

FT*

61

60