Low incidence of HCC in chronic hepatitis C patients with pretreatment liver stiffness measurements below 17.5 kilopascal who achieve SVR following DAAs

BACKGROUND AND AIMS

To evaluate the ability of pretreatment liver stiffness measurements (pLSM) to predict hepatocellular carcinoma (HCC), incident decompensation and all-cause mortality in chronic hepatitis C (CHC) patients who achieved sustained virological response (SVR) after treatment with direct-acting antivirals (DAAs).

METHODS

773 CHC patients with SVR after DAA treatment and no prior liver complications were identified retrospectively. Optimized cut-off of 17.5 kPa for incident HCC was selected by maximum Youden's index. Patients were grouped by pLSM: <10 kPa [reference], 10-17.4 kPa and ≥17.5 kPa. Primary outcomes were incident hepatocellular carcinoma and secondary outcomes were incident decompensated cirrhosis and all-cause mortality, analyzed using cox-regression.

RESULTS

Median follow-up was 36 months and 43.5% (336) had cirrhosis (LSM>12.5 kPa). The median pLSM was 11.6 kPa (IQR 6.7-17.8, range 2.5-75) and pLSM of <10 kPa, 10-17.4 kPa and 17.5-75 kPa was seen in 41.5%, 32.2% and 26.3%. During a median follow-up time of 36 months, 11 (1.4%) developed HCC, 14 (1.5%) developed decompensated cirrhosis, and 38 (4.9%) patients died. A pLSM of 17.5 kPa identified patients with a high risk of HCC with a negative predictive value of 98.9% and incidence rate of HCC in the 17.5-75 kPa group of 1.40/100 person years compared to 0.14/100 person years and 0.12/100 person years in the 10-17.4 kPa and <10 kPa groups, p<0.001.

CONCLUSION

Pretreatment LSM predicts risk of HCC, decompensation and all-cause mortality in patients with SVR after DAA treatment. Patients with a pLSM <17.5 kPa and no other risk factors for chronic liver disease appear not to benefit from HCC surveillance for the first 3 years after treatment. Longer follow-up is needed to clarify if they can be safely excluded from post treatment HCC screening hereafter.

Incidence, prevalence and risk factors for hepatitis C in Danish prisons

Hepatitis C virus (HCV) infection is prevalent among people in prison and prisons could therefore represent a unique opportunity to test risk groups for HCV. The aim of this sero-epidemiological study was to determine the incidence and prevalence of HCV infection and the corresponding risk factors in Danish prisons. Participants, recruited from eight Danish prisons, were tested for HCV using dried blood spots and filled out a questionaire with demographic data and risk factors for HCV infection. In total, 76.9% (801/1041) of all eligible prisoners consented to participate. The prevalence of HCV RNA positive prisoners was 4.2% (34/801) and the in-prison incidence rate was 0.7–1.0 per 100PY overall and 18-24/100PY among PWIDs. Infected prisoners were older than the overall population with a mean age of 42 years and only 17.6% (6/34) were younger than 35 years. The prevalence of PWID was 8.5% (68/801) and only 3% (2/68) of PWID were younger than 25 years. Among the PWID, 85.3% (58/68) had ever received opioid substitution therapy (OST) and 47.1% (32/68) were currently receiving OST. Risk factors associated with HCV infection were intravenous drug use, age ≥ 40 years, and being incarcerated ≥ 10 years. In conclusion, the prevalence of PWID in Danish prisons is low, possibly reflecting a decrease in injecting among the younger generation. This together with OST coverage could explain the low prevalence of HCV infection. However among PWIDs in prison the incidence remains high, suggesting a need for improved HCV prevention in prison.

Feasibility of transient elastography versus real-time two-dimensional shear wave elastography in difficult-to-scan patients

BACKGROUND AND AIMS

Transient elastography (TE) is hampered in some patients by failures and unreliable results. We hypothesized that real time two-dimensional shear wave elastography (2D-SWE), the FibroScan XL probe, and repeated TE exams, could be used to obtain reliable liver stiffness measurements in patients with an invalid TE examination.

METHODS

We reviewed 1975 patients with 5764 TE exams performed between 2007 and 2014, to identify failures and unreliable exams. Fifty-four patients with an invalid TE at their latest appointment entered a comparative feasibility study of TE vs. 2D-SWE.

RESULTS

The initial TE exam was successful in 93% (1835/1975) of patients. Success rate increased from 89% to 96% when the XL probe became available (OR: 1.07, 95% CI 1.06-1.09). Likewise, re-examining those with a failed or unreliable TE led to a reliable TE in 96% of patients. Combining availability of the XL probe with TE re-examination resulted in a 99.5% success rate on a per-patient level. When comparing the feasibility of TE vs. 2D-SWE, 96% (52/54) of patients obtained a reliable TE, while 2D-SWE was reliable in 63% (34/54, p < 0.001). The odds of a successful 2D-SWE exam decreased with higher skin-capsule distance (OR = 0.77, 95% CI 0.67-0.98).

CONCLUSIONS

Transient elastography can be accomplished in nearly all patients by use of the FibroScan XL probe and repeated examinations. In difficult-to-scan patients, the feasibility of TE is superior to 2D-SWE.

Microfibrillar-Associated Protein 4: A Potential Biomarker for Screening for Liver Fibrosis in a Mixed Patient Cohort

Background and Aims

A method for assessment of liver fibrosis and cirrhosis without the need for a liver biopsy is desirable. Microfibrillar-associated protein 4 (MFAP4) is a suggested biomarker for identification of high-risk patients with severe fibrosis stages. This study aimed to examine associations between plasma MFAP4 (pMFAP4) and transient elastography or chronic hepatitis C virus infection in drug users and in a mixed patient cohort with increased risk of liver disease. Moreover, the study aimed to identify comorbidities that significantly influence pMFAP4.

Methods

pMFAP4 was measured in samples from 351 drug users attending treatment centres and from 248 acutely hospitalized medical patients with mixed diagnoses. Linear and logistic multivariate regression analyses were performed and nonparametric receiver operating characteristic-curves for cirrhosis were used to estimate cut-off points for pMFAP4. Univariate and subgroup analyses were performed using non-parametric methods.

Results

pMFAP4 increased significantly with liver fibrosis score. pMFAP4 was significantly associated with chronic viral infection in the drug users and with transient elastography in both cohorts. In the mixed patient cohort, pMFAP4 was significantly increased among patients with a previous diagnosis of liver disease or congestive heart failure compared to patients with other diagnoses.

Conclusions

pMFAP4 has the potential to be used as an outreach-screening tool for liver fibrosis in drug users and in mixed medical patients. pMFAP4 level is positively associated with transient elastography, but additional studies are warranted to validate the possible use of pMFAP4 in larger cohorts and in combination with transient elastography.

Bouncing ball orbits and symmetry breaking effects in a three-dimensional chaotic billiard

We study the classical and quantum mechanics of a three-dimensional stadium billiard. It consists of two quarter cylinders that are rotated with respect to each other by 90 degrees and it is classically chaotic. The billiard exhibits only a few families of nongeneric periodic orbits. We introduce an analytic method for their treatment. The length spectrum can be understood in terms of the nongeneric and unstable periodic orbits. For unequal radii of the quarter cylinders the level statistics agree well with predictions from random matrix theory. For equal radii the billiard exhibits an additional symmetry. We investigated the effects of symmetry breaking on spectral properties. Moreover, for equal radii, we observe a small deviation of the level statistics from random matrix theory. This led to the discovery of stable and marginally stable orbits, which are absent for unequal radii.