Background/Aims: Considerable evidence suggests that iron could be a comorbid factor for liver injury in chronic
hepatitis C (CHC). Elevated iron indices are frequently described in CHC and may impact negatively on the
course of liver disease and on the response to interferon alfa therapy. Get more to visit this: http://www.jcehapatology.com
Similar to Hemochromatosis Gene Mutations: Prevalence and Effects on Pegylated-Interferon and Ribavirin Therapy Response in Chronic Hepatitis C in Sardinia
Similar to Hemochromatosis Gene Mutations: Prevalence and Effects on Pegylated-Interferon and Ribavirin Therapy Response in Chronic Hepatitis C in Sardinia (20)
3. JOURNAL OF CLINICAL AND EXPERIMENTAL HEPATOLOGY
function tests, autoantibody screening including antinu- Table 1 Base-line characteristics of 69 patients with HCV
clear factors and anti-thyroid antibodies and serum iron infection.a
parameters. Range
A complete response at the end of treatment was de- N 69
fined as the normalization of serum ALT levels and nega-
Gender (M/F) 53/16
tive serum HCV RNA. A sustained complete response
was defined as maintenance of remission after cessation Age (years) 51 Æ 2 25–65
of treatment for 24 weeks or more. Patients were divided Alanine aminotransferase (UI/dl) 139 Æ 29 85–480
in two groups according to HFE gene mutations: Group Viral genotype—n (%)
A, which included subjects with HFE gene wildtype and 1–4 46 (67%)
Group B, subjects with HFE gene mutations. Biochemical
2–3 23 (33%)
parameters, iron indices, liver histology, End of Treatment
Response (ETR) and Sustained Virologic Response (SVR) HFE genotype—n (%)
were compared between the two groups. Patients who dis- Wildtype 40 (58%)
continued treatment during follow-up were considered as HFE mutation 29 (42%)
virologic non-responders. All patients were informed of Serum iron (mg/dl) 127 Æ 8 15–312
the purpose of the study and of known side-effects associ-
Serum ferritin (ng/ml) 271 Æ 24 18–856
ated with both drugs, and written informed consent for
liver biopsy and therapy was obtained. Transferrin saturation index (%) 46% 26–62
Normal range: Transferrin, 110–370 mg/dl.
Statistical Analysis Plus–minus values are means Æ SEM.
a
Upper normal limit (ULN) of laboratory data: ALT, 41 UI/l; Serum iron,
Results are presented as mean Æ SEM. Statistical analyses 158 mg/dl; Serum ferritin, 250 ng/ml; Transferrin saturation, 45%.
were performed using StatView 5.0 (SAS Institute). De-
scriptive statistics were calculated and test of normality
Chronic Hepatitis C
were performed. For continuous variables, the values of
which were found to be distributed normally, parametric
statistical procedures were used, including paired t-test
and unpaired t-test. For discontinuous variables, non- Table 2 Base-line characteristics of 40 HFE wildtype patients
parametric procedures, including Wilcoxon's signed-rank and 29 patients with HFE mutation.a
test and Mann–Whitney U test, were carried out as appro-
HFE wildtype HFE mutation P-value
priate. Comparisons between the frequencies of observa-
tion were performed using the c2 test. Significance N 40 29
criteria of P 0.05 was used for all inferences. Gender (M/F) 32/8 25/4 ns
Age (years) 50 Æ 1 52 Æ 2 ns
ALT (UI/dl) 186 Æ 59 151 Æ 27 ns
RESULTS
AP (U/l) 183 Æ 13 209 Æ 22 ns
HFE Genotypes
GGT (U/l) 71 Æ 8 108 Æ 20 0.05
The clinical characteristics of the 69 HCV-infected pa-
Bilirubin total (mg/dl) 0.6 Æ 0.06 0.8 Æ 0.1 ns
tients are reported in Table 1. The base-line characteristics
of the 69 patients grouped by HFE genotype are shown in Serum iron (mg/dl) 118 Æ 9 149 Æ 13 ns
Table 2. At least one of the three HFE gene mutations was Serum ferritin (ng/ml) 280 Æ 34 327 Æ 32 ns
present in 42% of the patients. One patient was heterozy- Transferrin saturation(%) 43.4% 50% 0.01
gous for the C282Y mutation (1.4%), 22 were heterozy- Histological fibrosis
gous for the H63D mutation (31.8%), three (4.3%) were
Stage I 10/40 (25%) 4/29 (13.8%) P = 0.04b
heterozygous for the S65C mutation, two patients
(2.8%) were homozygous for the H63D mutation and Stage II 15/40 (37.5%) 5/29 (17.2%)
one patient (1.4%) was a compound heterozygote for Stage III 11/40 (27.5%) 10/29 (34.5%)
the H63D and S65C mutation. Stage IV 4/40 (10%) 10/29 (34.5%)
No significant differences were observed for age, gender Genotype—n (%)
distribution, ALT, serum iron and ferritin levels and viral
1–4 27 (67.5%) 19 (65.5%) ns
genotype between HFE mutant patients and wildtype ho-
mozygotes. 2–3 13 (32.5%) 10 (34.5%)
Transferrin saturation index (TSI) showed a significant a
Plus–minus values are means Æ SEM.
statistical difference between HFE mutant patients (50%) b 2
c test.
Journal of Clinical and Experimental Hepatology | September 2012 | Vol. 2 | No. 3 | 211–217 213
5. JOURNAL OF CLINICAL AND EXPERIMENTAL HEPATOLOGY
interferon.10 These observations indicate the important transferrin saturation index (TSI) showed a significant sta-
role of iron in the pathogenesis of CHC. In fact patients tistical difference between HFE mutant patients (50%) and
with combined hereditary hemochromatosis and chronic wildtype homozygotes (43.4%) (P 0.01). Instead, no signif-
hepatitis C infection presented advanced fibrosis/cirrhosis icant difference was observed for other indirect markers of
at a younger age and at a lower hepatic iron concentration iron stores such as serum iron and serum ferritin. These pa-
compared to HH patients. This supports the concept that rameters lack specificity, particularly in the face of chronic
the combination of iron overload and HCV has a potentiat- inflammatory conditions or alcohol-induced liver disease.27
ing effect on hepatic fibrogenesis.24 Previous reports suggested that TSI measurement appears
Iron can be a profibrogenic factor, acting as activator of to be the most sensitive method of detecting iron overload
both hepatic stellate cells and Kupffer cells and inducing states and showed that TSI values exceeding 45% correctly
liver inflammation or hepatocyte necrosis. In fact the pres- identified 97.9% of homozygotes for Hereditary Hemochro-
ence of stainable iron on liver biopsy of patients with viral matosis, with no false positives among the normal popula-
hepatitis correlates with a higher degree of necroinflamma- tion, and 22.2% of the heterozygote population. Detecting
tory activity and a higher score for fibrosis compared to the threshold for TSI to 45% could also identify other
those with no stainable iron.25 The coexistence of hemo- groups with relatively minor degrees of secondary iron over-
chromatosis gene mutations represents a genetic risk fac- load, such as chronic hepatitis C.33,34 Recent evidence
tor affecting the severity of chronic hepatitis C and the suggests that HFE gene mutations and a consequent mild
response rate to interferon therapy.26À28 iron overload may worsen the course of chronic hepatitis
The results of our study indicate that the prevalence C and increase the progression of fibrosis.22–35
of the three known HFE gene mutations in Sardinia is in The results of our study showed that a significant asso-
accordance with previous observations in other countries: ciation exists between advanced histological score and the
(5–10% for the C282Y mutation and 6–30% for the H63D presence of HFE gene mutation (c2, P = 0.04). The fact that
mutation),29,30 specifically 42% of our HCV-infected patients heterozygote for hereditary hemochromatosis and
patients carried at least one of these mutations. infected with hepatitis C virus report greater fibrosis than
Chronic Hepatitis C
Heterozygous C282Y status and homo- or heterozygosity those with homozygous wildtype provides additional evi-
for the H63D and S65C mutations do not usually induce dence that iron modulates fibrosis in chronic hepatitis C.
hemochromatosis phenotype and are rarely associated Despite these observations, the association between serum
with liver damage in healthy subjects.31 Nevertheless, labo- iron values, hepatic iron stores and hepatic necroinflam-
ratory abnormalities of iron metabolism (higher serum matory activity or fibrosis remains controversial. HFE
iron concentration, transferrin—saturation values and se- gene mutations may have a potentiating effect on histolog-
rum ferritin concentrations) have been detected in 15–20% ical severity, acting synergically with CHC in the develop-
of heterozygotes.6–26 Complications have been recognized ment of liver damage.
only when other disorders, such as alcoholism and viral Iron overload seems to impair antigen-specific immune
hepatitis are present.6–26 HFE gene mutations may responses by decreasing the generation of T cells and by
contribute to iron storage and could represent a clinically impairment of natural killer and T helper cell function. Pi-
relevant comorbid factor in patients with chronic hepatitis perno et al 3 suggested that iron overload in patients with
C. Sebastiani et al summarize the current status of the hemochromatosis may contribute to the persistence of
literature regarding the prevalence, hepatic distribution of HCV infection: iron overload may in theory promote viral
iron overload in liver disease.32 In this review the role of replication. Moreover, iron overload has been incriminated
HFE mutations as a risk factor for iron overload in CHC as one of the essential factors that hamper response to
has been studied in different populations, with discordant interferon-alpha in CHC.3–36 The amount of hepatic iron
results. Our results evidenced a correlation between HFE has been identified as one of these factors that adversely
gene mutation and iron overload. TSI is the only serum affect the likelihood of response to interferon-alpha; those
iron parameter that showed a statistically significant differ- patients with higher hepatic iron content are less likely to
ence between HFE gene wildtype and mutation, while serum respond to interferon therapy.37 Retrospective evidence
iron and serum ferritin were higher in HFE mutation but that the amount of hepatic iron may modulate the re-
did not obtain a statistically difference. We can assess that sponse of the hepatitis C virus to interferon therapy was
several aspecific factors seem to favor marked variations of provided by Van Thiel et al13 who reported that hepatic
serum iron and serum ferritin and we considered TSI as iron content of interferon nonresponders was found to
the most specific and sensitive parameter in identifying be almost twice that of responders. The influence of host
iron overload. The present study provides evidence support- and viral factors on the natural course of CHC and efficacy
ing the view that the HFE gene mutations are associated of PEG-IFN and Ribavirin therapy has been intensively
with significant abnormalities of iron metabolism and sug- studied. The presence of HFE gene mutations may be an
gests that patients with CHC accumulate iron as the result additional factor to be considered among those implicated
of interplay between genetic and acquired factors. In fact in the determination of a lower rate of sustained virological
Journal of Clinical and Experimental Hepatology | September 2012 | Vol. 2 | No. 3 | 211–217 215
7. JOURNAL OF CLINICAL AND EXPERIMENTAL HEPATOLOGY
hemochromatosis and chronic hepatitis C infection. J Hepatol. 31. Bassett ML, Halliday JW, Powell LW. HLA typing in idiopathic hemo-
2002;36:687–691. chromatosis: distinction between homozygotes and heterozygotes
25. Pietrangelo A. Iron, oxidative stress and liver fibrogenesis. with biochemical expression. Hepatology. 1981;1:120–126.
J Hepatol. 1998;28:8–13. 32. Sebastiani G, Walker AP. HFE gene in primary and secondary hepatic
26. Erhardt A, Maschner-Olberg A, Mellenthin C, et al. HFE mutations iron overload. World J Gastroenterol. 2007;13(35):4673–4689.
and chronic hepatitis C: H63D and C282Y heterozygosity are inde- 33. Tavill Anthony S. AASLD practice guidelines diagnosis and manage-
pendent factors for liver fibrosis and cirrhosis. J Hepatol. ment of hemochromatosis. Hepatology. 2001;33(5):1321–1328.
2003;38(3):335–342. 34. Olynyk JK, Cullen DJ, Aquilia S, Rossi E, Summerville L, Powell LW.
27. Piperno A, Vergani A, Maltosio I, et al. Hepatic iron overload in pa- A population based study of the clinical expression of the hemo-
tients with chronic viral hepatitis: role of HFE gene mutations. Hep- chromatosis gene. N Engl J Med. 1999;341:718–724.
atology. 1998;28. $9:1105–1109. 35. Bonkovsky HL, Troy N, McNeal K, et al. Iron and HFE or TfR1 muta-
28. Coelho-Borges S, Cheinquer H, Cheinquer N, Krug L, Ashton-Prolla P. tions as comorbid factors for development and progression of
HFE mutations prevent sustained virological response to interferon chronic hepatitis C. J Hepatol. 2002;37:848–854.
plus ribavirin in chronic hepatitis C patients with serum markers of 36. Izumi N, Enomoto N, Uchihara M, et al. Hepatic iron contents and
iron overload. Am J Gastroenterol. 2002;97:1570–1572. response to interferon alfa in patients with chronic hepatitis C rela-
29. Beutler Ernest, Felitti Vincent J, Koziol James A, Ho Ngoc J, tionship to genotypes of hepatitis C virus. Dig Dis Sci. 1996;41:
Gelbart Terri. Penetrance of 845G*A (C282Y) HFE hereditary 989–994.
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Chronic Hepatitis C
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