HCV Genotype Distribution and Clinical Characteristics of HCV Mono-Infected and HCV/HIV Co-Infected Patients in Liangshan Prefecture, Sichuan Province, China

Abstract

Objective: The present study aimed to characterize the genotype distribution and clinical characteristics of HCV monoinfected and HCV/HIV coinfected patients in the Liangshan Prefecture, Sichuan Province, China. Methods: All the patients were divided into HCV monoinfection and HCV/HIV coinfection groups according to whether they were complicated with HIV infection. The data from the two groups were collected. Results: In this study, HCV genotype 3 was the most common genotype in both groups, while HCV genotype 6 was significantly higher in the coinfection group than in the monoinfection group (p = 0.046). The white blood cell count, total bilirubin level, and HCV RNA were significantly higher in the HCV monoinfection group than that in the HCV/HIV coinfection group (p = 0.031; p < 0.001; p = 0.027, respectively). Conclusion: HCV prevalence was high in HIV-positive patients in the Liangshan Prefecture. Thus, incorporating screening and management of HCV monoinfection and HCV/HIV coinfection is needed in local region programs.

Introduction

Hepatitis C virus (HCV) is mainly transmitted through intravenous drug use, blood, and sexual contact. ¹ The infection can lead to inflammation, necrosis, and fibrosis of the liver and could lead to cirrhosis or hepatocellular carcinoma in some patients. ^{2 - 4} HCV is often described as a “silent killer” mainly because the virus has a long incubation period and the disease is prone to become chronic. ⁵ HCV infection is a major public health concern worldwide, and the global prevalence is about 1.0%, affecting approximately 71 million patients. ⁶ In 2016, the World Health Organization (WHO) launched a program to eradicate viral hepatitis as a public health threat by 2030 ⁷ ; China is also striving to achieve a similar goal. ⁸

HCV is a small, enveloped, single-stranded positive-sense ribonucleic acid virus.^9,10 The genome has significant heterogeneity and high variability. ¹¹ HCV is currently divided into six genotypes (GT) and multiple subtypes depending on the viral gene sequence.^12,13 The distribution of the HCV genotype is closely related to the infection route and regional location of the patients.^14,15 HCV genotype is significant in predicting the prognosis of hepatitis C and formulating the antiviral therapy plan.

Liangshan Yi Autonomous Prefecture is the largest Yi-inhabited area in China, southwest of China. Because of its unique geographical location and cultural environment, Liangshan Prefecture is one of the leading channels for drugs to enter the inland area of southwest China. The human immunodeficiency virus (HIV) infection rate of intravenous drug users in this area is about 10.1%. ¹⁶ Since HIV and HCV have a common transmission route, HCV monoinfection and HCV/HIV coinfection are common in this region. ^{17 - 19} Due to the differences in the infection routes and the specific geographical location of the Liangshan Prefecture, there may be some differences in the HCV genotype distribution and clinical characteristics of the monoinfected and coinfected patients. This phenomenon has been investigated in only a few studies. Thus, the present study aimed to analyze the HCV genotype distribution and clinical characteristics of HCV monoinfected and HCV/HIV coinfected patients in Liangshan Prefecture, Sichuan Province, China, and provide a clinical basis for individualized antiviral therapy.

Materials and Methods

Patients Selection

In this retrospective cohort study, all the patients were recruited from the Antiviral Therapy Center of the First People's Hospital of Yuexi County, Liangshan Prefecture from April 2021 to December 2021. The inclusion criteria were as follows: (1) the HCV antibody and HCV RNA were positive; (2) regardless of age and sex; (3) regardless of hepatitis B virus (HBV) or HIV coinfection. (4) Patients with incomplete clinical data were excluded.

The diagnosis of HCV infection was based on the Chinese guidelines for the prevention and treatment of hepatitis C (2019 version). ⁸ The diagnosis of HBV infection was according to the Chinese guidelines for preventing and treating chronic hepatitis B (2019 version). ²⁰ The diagnosis of HIV infection was according to the Chinese guidelines for diagnosing and treating AIDS (2018 version). ²¹

Clinical Laboratory Examination

Plasma HCV RNA was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The reagents (Shanghai Fosun Medical Science Co., Ltd, Shanghai, China) had a minimum limit of 15 IU/ml for HCV-RNA, and the instrument required was the X960 Real-Time PCR system. HCV genotyping was performed by the PCR-fluorescent probe method. The reagents (Sansure Biotech Inc., Changsha, China) could be used to detect genotype-1, -1b, -2, -3, and -6, and the instrument required was the SLAN96P Real-Time PCR system (Shanghai Hongshi Medical Treatment Technology Co., Ltd, Shanghai, China). The routine blood tests (white blood cell, lymphocyte, hemoglobin, platelet [PLT]) were carried out on the blood cell analyzer (BC-6000 automatic hematology analyzer, Mindray Biomedical Electronics Co., Ltd, Shenzhen, China). The liver function (alanine aminotransaminase [ALT], aspartate aminotransferase [AST], albumin, total bilirubin [TBil]) and renal function (blood urea, uric acid, and serum creatinine) were evaluated on the biochemical analyzer (BS-2000M automatic biochemical analyzer, Mindray Biomedical Electronics Co., Ltd, Shenzhen, China). Liver fibrosis or cirrhosis was diagnosed by an Aspartate aminotransferase-to-platelet ratio index (AST/[ULN]/PLT × 100] index over 2, a Fibrosis-4 (FIB-4) ([Age × AST]/[PLT × square root of ALT]) index over 3.25, or ultrasonography imaging.

Data Collection

Patients were divided into HCV monoinfection and HCV/HIV coinfection groups according to whether they were complicated with HIV infection. The following data were collected from the two groups: demographic characteristics (gender, age, route of HCV infection, HBV or HIV coinfection), virus-related data (HCV genotype and levels of serum HCV-RNA), clinical laboratory examinations (routine blood test, liver function, renal function), and cirrhosis status of the liver.

Statistical Analysis

All the data were sorted out by Excel 2019 software (Microsoft Corp., Redmond, WA, USA), and the database of patients with HCV monoinfection and HCV/HIV coinfection was established. The SPSS Version 24.0 software (IBM Corp., Armonk, NY, USA) was used for statistical analysis. The enumeration data were expressed as frequency or percentage, and the chi-square test was used for intergroup comparison. The measurement data were expressed as mean ± standard deviation ( $\overline{\chi }$  ± s). The normal distribution variables were analyzed using a t-test, while the nonnormal distribution data were analyzed using the Wilcoxon rank-sum test for intergroup comparison. Two-sided p-values were calculated for all tests, and p < 0.05 indicated a statistically significant difference.

Results

Demographic Characteristics

A total of 115 patients were recruited according to the inclusion criteria; 60 were HCV monoinfection, and 55 were HCV/HIV coinfection. The monoinfection group comprised 43 male and 17 female patients, whereas the coinfection group comprised 39 male and 16 female patients. The median age was 39.5 years (range: 28-77) in the monoinfection group and 38.0 years (range: 13-55) in the coinfection group. The most common route of HCV infection was intravenous drug use in both groups. In the HCV monoinfection group, 3 patients were diagnosed with HBV infection. No significant differences were observed in the gender, age, route of HCV infection, and combination with HBV infection between the two groups (Table 1).

Table 1.

The Demographic Characteristics of Patients.

Parameter	HCV monoinfection n = 60	HCV/HIV coinfection n = 55	p-value
Gender			0.929
Male, n (%)	43 (71.7)	39 (70.9)
Female, n (%)	17 (28.3)	16 (29.1)
Age (years)	39.5 (28-77)	38.0 (13-55)	0.081
< 20, n (%)	0	1 (1.7)
20-29, n (%)	2 (3.3)	3 (5.5)
30-39, n (%)	28 (46.7)	32 (58.2)
40-49, n (%)	19 (31.7)	14 (25.5)
50-59, n (%)	9 (15.0)	5 (9.1)
≥ 60, n (%)	2 (3.3)	0
Route of HCV infection			0.843
IDU, n (%)	38 (63.3)	34 (61.8)
Sexual, n (%)	22 (36.7)	20 (36.4)
Mother to child, n (%)	0	1 (1.8)
HBV coinfection, n (%)	3 (5.0)	0	0.245

IDU: Intravenous drug user.

HCV Genotype Characteristics of Patients

Among 115 samples, 65 were successfully genotyped for HCV while 50 were not genotyped. Among the successfully genotyped samples, HCV genotype 3 was the most common in both groups; however, no significant differences were observed between the two groups (p = 0.432). On the other hand, HCV genotype 6 was significantly higher in the HCV/HIV coinfection group than in the HCV monoinfection group (p = 0.046) (Table 2).

Table 2.

The HCV Genotype Characteristics of Patients.

HCV genotype	HCV monoinfection n = 60	HCV/HIV coinfection n = 55	p-value
GT 1, n (%)	2 (3.3)	1 (1.9)	1.000
GT 1b, n (%)	6 (10.0)	7 (12.7)	0.771
GT 2, n (%)	1 (1.7)	0	1.000
GT 3, n (%)	22 (36.7)	16 (29.1)	0.432
GT 6, n (%)	2 (3.3)	8 (14.5)	0.046*
Unclassified, n (%)	27 (45.0)	23 (41.8)	0.851

GT: Genotype.

* HCV genotype 6 was significantly higher in the HCV/HIV coinfection group than in the HCV monoinfection group (p = 0.046).

Clinical Characteristics of Patients

We compared the clinical characteristics of the two groups. We found the white blood cell count, TBil level, and HCV RNA were significantly higher in the HCV monoinfection group than in the coinfection group (p = 0.031; p < 0.001; p = 0.027, respectively) (Table 3).

Table 3.

The Clinical Characteristics of Patients.

Parameter	HCV monoinfection n = 60	HCV/HIV coinfection n = 55	p-value
Routine blood test
WBC × 109/L	6.64 ± 1.89	6.04 ± 2.06	0.031*
NEU × 109/L	3.91 ± 1.42	3.47 ± 1.64	0.141
LYM × 109/L	2.08 ± 0.83	1.96 ± 0.85	0.308
HGB, g/L	157.57 ± 23.87	149.67 ± 22.44	0.079
PLT × 109/L	195.26 ± 76.92	183.38 ± 71.99	0.407
Liver function
ALT, U/L	90.97 ± 74.78	70.40 ± 60.11	0.101
AST, U/L	63.00 ± 52.41	53.89 ± 33.03	0.516
ALB, g/L	43.69 ± 5.11	43.80 ± 4.32	0.869
TBIL, μmol/L	14.40 ± 7.79	9.11 ± 5.04	< 0.001*
Renal function
Urea, mmol/L	5.30 ± 1.28	5.21 ± 1.45	0.713
Creatinine, μmol/L	67.64 ± 19.12	66.09 ± 13.12	0.738
UA, μmol/L	360.64 ± 83.85	337.41 ± 82.69	0.094
HCV RNA, log10 IU/mL	5.45 ± 1.40	4.81 ± 1.41	0.027*
Liver fibrosis, n (%)	8 (13.33)	5 (9.09)	0.563

WBC: white blood cell; NEU: neutrophil granulocyte; LYM: lymphocyte; HGB: hemoglobin; PLT: platelets; ALT: alanine transaminase; AST: aspartate aminotransferase; ALB: albumin; TBIL: total bilirubin; UA: uric acid; HCV RNA, ribonucleic acid of hepatitis C virus.

* The white blood cell count, TBil level, and HCV RNA were significantly higher in the HCV monoinfection group than in the coinfection group (p = 0.031; p < 0.001; p = 0.027, respectively).

Discussion

China has a heavy disease burden of HCV infection. ²² The HCV infection rate of different populations in China is variable. ²³ The HCV infection rate of intravenous drug users is about 61.4%,^14,24 and therefore, intravenous drug use is the main infection route of HCV infection. ²⁵ Since HIV and HCV share a common route of transmission, HCV/HIV coinfection is common in the Liangshan Prefecture. In this study, we examined the HCV genotype distribution and clinical characteristics of patients with HCV monoinfection and HCV/HIV coinfection in the Liangshan Prefecture. To the best of our knowledge, this is one of the few studies on HCV genotype distribution and clinical characteristics of patients with HCV monoinfection and HCV/HIV coinfection in the Liangshan Prefecture. Thus, understanding the HCV genotype distribution and clinical characteristics of these patients is essential to establishing a clinical basis for individualized antiviral therapy.

Liangshan Prefecture has a unique geographical location and cultural environment. The local economy and culture of this Prefecture are relatively backward compared to eastern China. The public awareness of HCV and HIV prevention and control is low, which increases the risk of both infections. Therefore, we must continue to strengthen the drug control in the Liangshan Prefecture and popularize HCV and HIV prevention and control knowledge to the local public.

HCV is a single-stranded linear RNA virus. During the viral replication, RNA polymerase does not perform the function of proofreading. Therefore, HCV mutates easily, ²⁶ and the degree of variation in different sections of the same genome varies greatly, resulting in six genotypes and multiple subtypes. ¹³ The distribution of HCV genotypes is related to the infection route and regional location of the patients. In this study, HCV genotype 3 was most common in both groups while HCV genotype 6 was higher in the coinfection than in the monoinfection group. Some studies demonstrated that HCV genotype 1 constitutes the highest proportion, accounting for about 56.8% of all HCV-infected patients, followed by HCV genotype 2a which accounts for about 24.1% of all HCV infections. ²⁷ Presently, the prevalent HCV genotypes in China are 1, 2, 3, and 6 (genotypes 4 and 5 are rare). ⁸ Among these, HCV genotype 1b accounts for 66%, and HCV genotype 2a accounted for 14% of all subtypes. ²⁴ HCV genotype 1b is mainly distributed in northeast China and HCV genotype 2a is mainly distributed in the southwest region. ²⁴ Some studies have reported that the HCV genotype of HCV/HIV coinfection patients in Kunming (China) is mainly subtype 1b. ²⁸ However, in Guangdong (China), the HCV genotype of HCV/HIV coinfection patients was mainly genotype 6a, followed by genotypes 1b and 3. ²⁹ Based on these results, there are still some differences in the HCV genotype between Liangshan Prefecture and other regions in China. In the present study, the HCV genotype of some samples could not be typed, owing to the low viral load of HCV RNA.

HCV/HIV coinfection can accelerate the disease process of hepatitis C, which increases the hepatotoxicity of antiretroviral therapy and affects immune reconstruction.^30,31 Therefore, HCV/HIV coinfection has become a major public health problem endangering the local people. In this study, the clinical characteristics, such as the white blood cell count, TBil, and HCV RNA, were significantly higher in the HCV monoinfection group than in the coinfection group. The pathogenesis of HCV infection includes immune-mediated and HCV injury. ³² The HCV-induced host immune response is the primary cause of liver injury. ³³ However, HCV may directly cause cytopathy, which is also one of the mechanisms of liver injury. In this study, the levels of HCV RNA in the monoinfection group were higher, and the liver injury may be severe.

Nevertheless, the present study has several limitations: small population size, single-center data analysis, and the genotyping reagent could not cover all the genotypes. Our results complement the scarce information currently reported on the Liangshan Prefecture HCV monoinfection and HCV/HIV coinfection epidemics and have great potential to be generalized in the HCV monoinfection and HCV/HIV coinfection in the Liangshan Prefecture. However, multicenter studies using a large population and several reagents to assess the other genotypes are essential to substantiate the current findings.

Conclusion

HCV prevalence is high in HIV-positive patients in the Liangshan Prefecture. Incorporating screening and management of HCV monoinfection and HCV/HIV coinfection into the local region programs is imperative. The analysis of HCV genotype distribution and clinical characteristics of HCV monoinfected and HCV/HIV coinfected patients in the Liangshan Prefecture is crucial for formulating individualized antiviral treatment plans and predicting the efficacy and long-term prognosis of the antiviral treatment.