Hepatitis C virus (HCV) is a globally significant cause of chronic liver disease, affecting an estimated 170-185 million individuals and resulting in approximately 3-4 million new infections annually [1]. HCV infection progresses silently in most cases, with 80-85% of acute infections advancing to chronicity, significantly contributing to liver cirrhosis, hepatocellular carcinoma, and liver failure [2,3]. The virus, a positive-strand RNA member of the Flaviviridae family, is characterized by extensive genetic variability, which influences clinical manifestations and treatment outcomes [4]. 

HCV is classified into seven major genotypes and numerous subtypes. Globally, genotype 1 is the most prevalent, followed by genotypes 2 and 3, with genotype 3 being particularly common in India and Southeast Asia [5]. Genotypes 1 and 4 are associated with more severe disease progression and resistance to treatment, whereas genotypes 2 and 3 tend to respond better to therapy [6]. This variability is not uniformly distributed across the viral genome, with conserved regions such as the 5’ non-coding region and hypervariable regions like E1 and E2. These genetic differences have clinical implications, including varying susceptibility to antiviral treatments and differing associations with liver disease severity [7]. 

Beyond its intrinsic genetic diversity, HCV infection is often complicated by co-factors such as jaundice, ascites, and HIV co-infection. Jaundice and ascites are common complications of advanced liver disease, reflecting hepatic decompensation [8]. HIV co-infection further exacerbates the disease course, accelerating fibrosis and altering immune responses [9]. These clinical manifestations vary with genotype, highlighting the importance of studying genotype-specific correlations in chronic HCV infection [10], [11] 

This study aims to evaluate the distribution of HCV genotypes and their correlation with clinical conditions such as jaundice, ascites, and HIV status in a cohort of chronically infected patients. By focusing on these associations, the research seeks to enhance the understanding of genotype-specific variability and its clinical relevance, particularly in the Indian context. 

Study Setting and Design

This prospective analytical study was conducted in the Microbiology Department of Medical College and Hospital, Kolkata, from January 2020 to January 2021. 

Study Population

Chronic HCV infected patients attending GastroEnterology Department of Medical College, Kolkata were selected for this study.

Inclusion Criteria: 

• Patients aged 11 years or older.
• Diagnosed with chronic HCV infection confirmed by HCV RNA using GeneXpert RT-PCR.

Exclusion Criteria: 

• Acute HCV infection.
• Co-infection with hepatitis B or other liver diseases.

Sample Size

The required sample size was calculated as 70 using the formula:

n = 4pq/L2

Where p = 0.25 (prevalence of HCV)11, q = 1-p, and L = 10.34% (allowable error). This ensured adequate statistical power for meaningful analyses. 

Data Collection

• A structured proforma was used to collect clinical and demographic data, including age, sex, jaundice, and ascites.
• The presence or absence of jaundice was confirmed through blood testing for liver function tests (LFTs).
• HIV status was determined by serological testing using the “three-test method” at the NACO testing lab within the same institution.
• HCV genotyping was performed using PCR-based assays, which classified genotypes into 1a, 1b, 2, and 3.

Statistical Analysis

• Data were analyzed using SPSS v27.0 and GraphPad Prism v5.
• Associations between HCV genotypes and clinical parameters were evaluated using chi-square and Fisher’s exact tests for categorical data.
• A p-value <0.05 was considered statistically significant.

Ethical Considerations

The study was approved by the institutional ethics committee. Written informed consent was obtained from all participants, and confidentiality was ensured throughout the research process. 

Distribution of HCV Genotypes The study analyzed 70 patients with chronic HCV infection. Among the genotypes identified, Genotype 3 was the most prevalent, observed in 45 patients (64.3%), followed by Genotype 1a in 18 patients (25.7%), Genotype 2 in 4 patients (5.7%), and Genotype 1b in 3 patients (4.3%).

1. Correlation with Jaundice, Ascites, and HIV Status the clinical features of jaundice, ascites, and HIV status were analyzed across different HCV genotypes.
2. Jaundice: Jaundice was observed in 57 patients (81.4%), with the highest prevalence in Genotype 3 (86.7%). However, the correlation between genotype and jaundice was not statistically significant (p=0.4998).
3. Ascites: Ascites was present in 10 patients (14.3%), predominantly in Genotype 1b (33.3%). Similar to jaundice, the correlation with genotype was not statistically significant (p=0.4150).
4. HIV Status: HIV co-infection was noted in 12 patients (17.1%). A significant correlation was found between HIV status and HCV genotype, with Genotype 1b showing the highest proportion of reactive HIV status (33.3%: p=0.0075).
   
   

                   *Significant correlation observed.

Genotypic Distribution of HCV The study found that Genotype 3 was the most prevalent (64.3%), followed by Genotype 1a (25.7%), Genotype 2 (5.7%), and Genotype 1b (4.3%). This distribution aligns with previous studies conducted in India, where Genotype 3 has been reported as the dominant strain, particularly among individuals with a history of intravenous drug use[12]. Similar findings have been observed in South Asia, where Genotype 3 is more common than Genotype 1, which predominates in North America and Europe[13]. The higher prevalence of Genotype 3 in this cohort may also be attributed to regional epidemiological trends and transmission patterns.

Correlation with Jaundice and Ascites

Jaundice was present in 81.4% of the patients, with the highest prevalence observed in Genotype 3 (86.7%), though this correlation was not statistically significant (p=0.4998). Previous studies have suggested that HCV Genotype 3 is associated with higher bilirubin levels and increased liver fibrosis, which could contribute to jaundice[14]. However, other studies have reported no significant association between specific genotypes and jaundice, suggesting that host factors and disease progression may play a more critical role [15].

Ascites was present in 14.3% of patients, with the highest occurrence in Genotype 1b (33.3%). Although the association between ascites and genotype was not statistically significant (p=0.4150), Genotype 1b has been linked to more aggressive liver disease and a higher risk of cirrhosis in previous studies [16]. A study in Egypt, where Genotype 4 is predominant, also reported a higher frequency of ascites in patients with advanced liver disease, reinforcing the notion that genotypic variability may influence clinical progression [17].

Correlation with HIV Status. The significant correlation between HIV co-infection and HCV Genotype 1b (p=0.0075) is an important finding. This finding is consistent with prior studies showing that Genotype 1, particularly 1b, is more common among HIV co-infected individuals, possibly due to shared transmission routes such as intravenous drug use [18]. Co-infection with HIV accelerates HCV-related liver disease progression, leading to higher rates of cirrhosis and hepatocellular carcinoma[19]. These findings emphasize the need for integrated screening programs for HCV in high-risk populations, particularly among HIV-infected individuals, to facilitate early diagnosis and appropriate antiviral interventions.

Clinical and Public Health Implications Understanding the distribution of HCV genotypes and their association with clinical manifestations is crucial for optimizing disease management. The predominance of Genotype 3 in this study suggests a need for genotype-specific treatment strategies, particularly as Genotype 3 has been associated with steatosis and rapid fibrosis progression [20]. Additionally, the significant correlation between Genotype 1b and HIV co-infection underscores the need for enhanced surveillance and patient education programs, particularly for individuals at high risk of HCV-HIV co-infection. Strategies such as harm reduction programs, safe injection practices, and routine HCV screening in HIV care settings can help mitigate the impact of dual infections.

Limitations

The study is limited by its relatively small sample size and single-center design, which may affect the generalizability of findings. Larger multicenter studies are needed to further validate these genotype-specific associations.

This study highlights the genotypic distribution of hepatitis C virus (HCV) in chronically infected patients and its correlation with jaundice, ascites, and HIV status. Genotype 3 was the most prevalent, aligning with regional epidemiological trends, while Genotype 1b showed a significant association with HIV co-infection. Although no statistically significant correlation was observed between genotype and jaundice or ascites, the findings suggest that genotype-specific differences may influence disease progression, particularly in advanced liver disease. 

The significant association between Genotype 1b and HIV status underscores the need for integrated screening and management approaches for co-infected individuals. Additionally, given the high burden of Genotype 3, early detection and genotype-specific treatment strategies should be prioritized to mitigate the risk of rapid fibrosis progression and hepatocellular carcinoma. 

These findings contribute to the growing understanding of HCV genotypic variability and its clinical implications. Future multicenter studies with larger sample sizes are needed to further validate these associations and refine genotype-based management protocols for chronic HCV infection. 

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