Liver function in dengue and its correlation with disease severity: a retrospective cross-sectional observational study in a tertiary care center in Coastal India

Clinical correlations of plasma sphingosine-1-phosphate and sphingolipid key enzymes in severe dengue using laboratory and machine learning approach

BACKGROUND

Sphingolipids are crucial for vascular integrity and cellular homeostasis, with recent studies highlighting their role in viral diseases.

OBJECTIVES

The study aimed to assess the plasma levels of sphingolipids, specifically Sphingosine-1-phosphate (S1P) and the key enzymes of sphingolipid metabolism: Sphingomyelin synthase (SMS1), Ceramide Kinase (CERK) and acid ceramidase (ASAH1) and its association with clinical outcomes of dengue.

METHODS

This prospective cohort study had 102 dengue cases with 17 severe dengue (SD), 33 dengue with warning signs (DWW), 52 dengue without warning signs (DWOW) along with 10 each from other febrile illnesses and healthy controls. Blood was collected across febrile, defervescence, and convalescence phases. Plasma levels of S1P and the enzymes were measured using ELISA, mRNA using qRT-PCR. Predictive efficacy was determined using Support vector machine (SVM) models.

RESULTS

Study showed a significant reduction in S1P levels across all dengue forms during febrile phases, with further decline in SD during the critical phase (P < 0.05).mRNA levels of the enzymes were increasing during critical phase (P ≤ 0.001) with no significant difference noted in their respective protein levels. S1P and SMS1 levels correlated significantly with clinical severity indicators, including hematocrit, albumin, platelet count, and liver enzymes. SVM analysis identified CERK levels along with platelet count, HCT, and ALT as markers with high predictive accuracy for dengue severity.

CONCLUSION

The study reports an association of sphingolipids with dengue virulence, emphasizing the role of S1P metabolism in disease progression and plasma leakage, and highlighting the potential of targeting sphingolipids in managing severe dengue.

Inter-host diversity associated with age, sex, and menstrual cycle modulates clinical manifestations in DENV-2 patients

Dengue virus (DENV-2) remains a global threat, yet the influence of age, sex, and menstrual status on its epidemiology and genetic diversity is underexplored. We analyzed 2136 hospitalized DENV-2 patients (ages 0-86) using whole-genome sequencing (WGS) to examine how these host factors shape interhost viral diversity and clinical manifestations. Young adult males (19-35 years) had the highest prevalence with sex-based clinical differences where females exhibited severe hematological changes, while males showed increased hepatic injury. Premenopausal females harbored more diverse viral populations, whereas postmenopausal women experienced pronounced platelet depletion. Dengue virus WGS identified 1100336 single nucleotide variants (SNVs) across 2932 genomic positions, with greater viral diversity in adults and females. Significant SNV burdens were observed in the E, NS3, and NS5 genes of the virus. These interconnected findings underscore the profound impact of age, sex, and menstrual status on DENV-2 epidemiology which merits inclusion into the disease pathophysiology.

Dengue with liver involvement is associated with serum soluble thrombomodulin and P-selectin levels

BACKGROUND

The pathogenesis of liver damage in dengue patients has not been clarified. In this study, we sought to identify the factors that are associated with dengue-induced liver damage and evaluate the associations of cytokines/chemokines, including platelets, neutrophils, activated endothelial cells and other inflammatory factors, with liver damage.

METHODS

We collected and analysed clinical data from 106 hospitalized dengue patients and evaluated the serum levels of platelet (soluble P-selectin [sP-selectin] and soluble CD40 ligand [sCD40L]), neutrophil (neutrophil elastase [NE] and neutrophil myeloperoxidase [MPO]) and endothelial cell (soluble thrombomodulin [sTM]) activation markers, as well as inflammatory mediators, including C-X-C motif chemokine ligand 2 (CXCL2), interleukin (IL)-2, IL-4, IL-6, IL-10, tumour necrosis factor-α and interferon-γ (which are associated with liver damage), in 32 patients.

RESULTS

In total, 106 dengue patients were included in this study. The patients were categorized into dengue with warning signs (DwWS), dengue without warning signs (DwoWS) and severe dengue (SD). Twenty-four patients (22%) had DwWS and 1 patient (1%) had SD. Compared with the DwoWS group, the serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transferase levels in the DwWS/SD group were significantly greater (p<0.001, p<0.001 and p=0.001, respectively). A long time to onset (odds ratio [OR] 1.495 [95% confidence interval {CI} 1.063 to 2.101], p=0.021), thrombocytopenia (OR 4.166 [95% CI 1.11 to 15.629], p=0.034) and concomitant fatty liver (OR 6.326 [95% CI 1.57 to 25.493], p=0.009) were risk factors for dengue-related liver dysfunction. Compared with patients with normal liver enzyme levels, serum sP-selectin levels were significantly lower (p=0.012), sTM levels were higher (p=0.047), serum ALT and AST levels were positively correlated with sTM (r=0.411, p=0.02 and r=0.419, p=0.039; respectively) and AST levels were negatively correlated with sP-selectin levels (r=-0.441, p=0.011) in dengue patients.

CONCLUSIONS

Dengue fever with hepatic involvement is related to serum sTM and sP-selectin levels, thus suggesting that platelet and endothelial cell activation may be involved in the pathogenesis of liver damage and can be used as early predictors of dengue liver damage.

Genomic hotspots in the DENV-2 serotype (E, NS4B, and NS5 genes) are associated with dengue disease severity in the endemic region of India

Dengue virus (DENV) infection manifests a wide spectrum of clinical outcomes, ranging from mild fever to severe and potentially fatal disease, yet the factors driving this variability remain poorly understood. This study aims to unravel the relationship between clinical manifestations of dengue and the genetic diversity of the virus, providing insights into the genomic variability driving disease severity. To achieve this, serum samples were collected during a dengue outbreak in National Capital Region-Delhi, India, from June to November 2023. Serotyping of RNA isolated from 4,045 clinical serum samples revealed DENV-2 as the predominant serotype in circulation (n = 3702). Whole-genome sequencing for 3702 clinical samples was performed using Oxford Nanopore Technology (ONT) further yielding 3254 DENV-2 genomes with >50% coverage. However, all of them identified the cosmopolitan genotype of DENV-2, forming a distinct monophyletic cluster in the global phylogenetic tree. Comprehensive variant analysis uncovered 1,618,158 single nucleotide variations (SNVs) across the sequenced DENV-2 population. The clinico-genomic approach carried out in 1294 samples, mild (n = 473), moderate (n = 405) and clinically severe (n = 416), reveals a significant burden of SNVs in various genomic regions linked to differential disease outcomes. Statistical analyses, including Fisher's exact test and phi-correlation, identified hotspot regions in the Envelope (E), NS4B, and NS5 genes, where SNVs were strongly associated with mild and clinically severe phenotypes, providing insights into the genomic determinants of disease severity. Interestingly, the clustering of severity-associated SNVs in these genomic hotspot regions highlights their potential as therapeutic targets within the DENV genome. These findings offer a promising direction for developing early mitigation strategies and targeted interventions to manage the progression of severe DENV infections.

Hypoalbuminemia as a predictor of severe dengue: a systematic review and meta-analysis

INTRODUCTION

Dengue fever is a significant health concern globally, especially in tropical regions. Identifying reliable markers for severe dengue, such as hypoalbuminemia, is crucial for early diagnosis and treatment.

METHODS

This review systematically explores the association between hypoalbuminemia and severe dengue. We searched databases including PubMed, Embase, Scopus, Cochrane, and Web of Science until 28 December 2023, focusing on studies that reported albumin levels in dengue patients. Our selection criteria aimed at observational studies, from which data extraction and quality assessment were performed using Nested- Knowledge and the Newcastle-Ottawa Scale.

RESULTS

A meta-analysis of 17 studies involving 974 severe and 18,496 non-severe dengue patients identified a standardized mean difference (SMD) in albumin levels of -1.625 g/dL (95% CI: -3.618 to -0.369). Subgroup analysis indicated more pronounced hypoalbuminemia in pediatric patients, with a pooled SMD of -1.08 g/dL (95% CI: -1.71 to -0.45). Our analysis demonstrated the link between hypoalbuminemia and severe dengue, indicating a significant pooled relative risk of 2.286, within 95% CI 1.308 to 3.996.

CONCLUSIONS

The study confirms hypoalbuminemia as a significant predictor of severe dengue. Recognizing hypoalbuminemia in dengue patients can aid clinicians in forecasting the severity, potentially improving patient outcomes through targeted therapeutic strategies.

Significance of diagnostic and therapeutic potential of serum endothelial and inflammatory biomarkers in defining disease severity of dengue infected patients

Dengue virus (DENV) mediated disease severity leads to fatality among infected patients. Immune sentinels recognize DENV thereby secreting inflammatory mediators, endothelial biomarkers and anticoagulation factors. Absence of any diagnostic biomarkers for early identification of severe dengue (SD) patients has hindered disease management. Present study is aimed to evaluate diagnostic potential of these biomarkers along with their therapeutic targets for disease severity. Dengue infection was screened among 214 symptomatic patients and 25 healthy individuals by qRT-PCR, NS1-antigen, anti-dengue-IgM, anti-dengue-IgG ELISA and categorized them according to WHO-classification, 2009. Dengue viral-load and serotypes were determined by qRT-PCR. Serum-protein concentrations of inflammatory mediators (MIF, PAF, MMP2, MMP9, MCP1, RANTES, STNFRI, ST2, EOTAXIN), endothelial biomarkers (SDC1, VEGF, ANGPT2), anticoagulation factors (sTM, vWF, TF, PAI) were determined by sandwich ELISA. Statistical, PPI-network, hub-proteins, drug prediction analysis were performed by GraphPad-Prism9, STRING, Cytoscape-cytoHubba, DrugBank online, TTD, respectively. Among 81 dengue infected patients, significantly higher levels of MIF, PAF, sTNFRI, MMP9, VEGF, ANGPT2, MMP2, RANTES, SDC1 were detected among SD patients compared to non-severe ones, with excellent and good diagnostic potential of first (> 77.11, > 57.57 ng/ml, > 3226 pg/ml) and next three (> 105.3 ng/ml, > 12,380, > 8284 pg/ml) biomarkers, respectively. Serum MIF, PAF, MMP9, sTNFRI levels were significantly higher among hospitalized (p-value: 0.0081-0.0499), high-viral-load (p-value: 0.0266-0.0466) and DENV-2, 4 (p-value: < 0.0001-0.0298) infected patients. PPI-network analysed MMP9, PAI, vWF, ANGPT2, sTM, sTNFRI, MIF as hub-proteins targeted by FDA-approved/experimental drugs. This study recognized serum-biomarkers: MIF, PAF, sTNFRI, MMP9, VEGF, ANGPT2 to have significant diagnostic potential for identification of SD cases.

Predicting the risk of mortality in children with dengue-induced hepatitis admitted to the paediatric intensive care unit

BACKGROUND

Dengue-associated acute liver failure (PALF) accounts for a high mortality rate in children admitted to the pediatric intensive care unit (PICU). To date, there is a lack of data on clinical algorithms for estimating the risk of mortality in pediatric patients with dengue-induced severe hepatitis (DISH).

AIM

To determine the prevalence of PALF and identify the predictors of mortality among patients with DISH.

METHODS

This single-institution retrospective study was performed at a tertiary pediatric hospital in Vietnam between 2013 and 2022. The primary outcome was in-hospital mortality in pediatric patients with DISH, which was defined as either aspartate aminotransferase > 350 IU/L or alanine aminotransferase > 400 IU/L. Prognostic models for estimating the risk of death among patients with DISH were developed using a predefined set of clinical covariables and hepatic biomarkers on PICU admission and during the first 72 hours of admission. Area under the curve, multivariable logistic regression, and multiple imputation using the chained equation for missing values were performed. Backward stepwise model selection based on the Akaike information criterion was employed. Bootstrapping, calibration slope, and Brier score were used to assess the final models.

RESULTS

A total of 459 children with DISH were included in the analysis. The median patient age was 7.7 years (interquartile range: 4.3-10.1 years). The prevalence of dengue-associated PALF in children with DISH was 18.3%. Thirty-nine DISH patients developing PALF (8.5%) died. Hepatic biomarkers, including the international normalized ratio (INR) ≥ 2.11 and total serum bilirubin (≥ 1.7 mg/dL), showed high predictive values for mortality (all P values < 0.001). Multivariable models showed the significant clinical predictors of death from dengue-induced PALF in patients with DISH, including reduced level of consciousness (pain and unresponsive levels on the Alert, Verbal, Pain, Unresponsive scale), high vasoactive-inotropic score (> 30), and elevated levels of blood lactate, INR, and serum bilirubin. The final prognostic model demonstrated high discrimination, Brier score, and an acceptable calibration slope.

CONCLUSION

The prevalence of PALF in children with DISH is 18.3%. We developed robust prognostic models to estimate the risk of death in hospitalized children with severe dengue-induced hepatitis.

Newest "Co-Members" of the 1000s Club: A Case of Severe Transaminitis Secondary to Epstein-Barr and Dengue Virus Co-Infection in a Returning Traveler

Background

Timely identification of the etiology of transaminitis is critical in informing subsequent management as strategies can vary from supportive care to urgent transplant assessment. This is especially important in returning travelers as there may be multiple causes of injury that need to be addressed.

Case report

We present a case of severe transaminitis secondary to non-hepatitis viral co-infections. A 28-year-old south Asian male returning traveler presented with an acute liver injury (aspartate aminotransferase/alanine aminotransaminase levels of ≥4000 IU/l) and marked jaundice. A thorough and expanded work-up of acute hepatitis was negative aside from positive mononucleosis spot testing and positive dengue fever serologies. This atypical presentation of mononucleosis and dengue fever was managed conservatively, and the patient was discharged with outpatient follow-up after an eight-day admission.

Conclusions

Usually, non-hepatitis viruses typically do not present with severe transaminitis or hyperbilirubinemia. These viruses, such as infectious mononucleosis and dengue fever, may work synergistically to cause an elevated inflammatory response, resulting in severe transaminitis in returning travelers. In the absence of a classic clinical presentation, clinicians should be aware of co-infections in returning travelers and test for them based on a thorough history and physical examination.

LEARNING POINTS

The differential diagnosis for severe transaminitis is narrow and commonly includes viral hepatitis (A-E), drug-induced liver injury, vascular and autoimmune causes; however other causes exist, and greater clinical awareness is needed.This case study demonstrates that even in the absence of a classic clinical presentation; in returning travelers, clinicians should have a low index of suspicion to order appropriate screening serologies based on a thorough history and physical examination as they can be sensitive diagnostic tools in detecting the etiology of severe transaminitis.In rare cases, non-hepatitis virus may act synergistically to cause severe transaminitis and should be considered in returning travelers when viral hepatitis serologies are negative.

Association of Liver Function Tests With the Severity and Outcome of Dengue Fever in Children

Background Dengue is one of the most common vector-borne diseases in India, and it is transmitted by Aedes family mosquitoes. Hepatic injury is known to occur from dengue infection. Direct hepatotoxicity and deranged host immune responses to the virus are responsible for this hepatic dysfunction. Hence, the study was undertaken to understand the deranged hepatic enzymes using liver function tests (LFTs) and the severity and outcome of dengue fever in children. Methods This study is an observational-descriptive study conducted between June 2022 and May 2024. The study population includes children between the ages of one month and 16 years who have been diagnosed with dengue fever and admitted to pediatric wards and pediatric intensive care units (PICUs), with a sample size of 151. Informed consent from guardians and institutional ethical clearance were obtained. Results A total of 4.8% (N = 7) mortality was seen in this study with dengue patients. Hepatomegaly was seen in 34% (N = 49) of cases. There is a clear statistical significance that is seen among the non-survived and survived dengue patients with a 10-fold increase in serum glutamic-oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) levels, respectively, along with total bilirubin, activated partial thromboplastin time (APTT), and prothrombin time (PT). Conclusions The current study shows that deranged LFTs are associated with more severe disease with more PICU admissions and mortality of the disease. The evidence clearly indicates the inclusion of LFTs as a routine investigation to understand the severity of the disease and the prognosis of the outcome.

Liver involvement in dengue: A systematic review

Liver involvement is an unusual yet frequently overlooked dengue complication. Pivotal for an efficient clinical management, the early diagnosis of dengue-associated liver involvement relies on an accurate description of its clinical and biological characteristics, its prognosis factors, its association with severe dengue and its clinical management. We conducted a systematic review by searching PubMed and Web of Science databases for original case reports, cohort and cross-sectional studies reporting the clinical and/or biological features of dengue-associated liver involvement. The study was registered in PROSPERO (CRD42021262657). Of the 2552 articles identified, 167 were included. Dengue-associated liver involvement was characterised by clinical features including abdominal pain, hepatomegaly, jaundice, nausea/vomiting, and an echogenic liver exhibiting hepatocellular necrosis and minimal inflammation. Elevated Aspartate Aminotransferase and Alanine Aminotransferase but also elevated bilirubin, Alkaline Phosphatase, gamma-glutamyl transferase, increased International Normalised Ratio, creatinine and creatine kinase, lower albumin and prolonged prothrombin and activated partial thromboplastin time were prevalent in dengue-associated liver involvement. Cardiovascular and haematological systems were frequently affected, translating in a strong association with severe dengue. Liver involvement was more common in males and older adults. It was associated with dengue virus serotype-2 and secondary infections. Early paracetamol intake increased the risk of liver involvement, which clinical management was mostly conservative. In conclusion, this systematic review demonstrates that early monitoring of transaminases, clinical assessment, and ultrasound examination allow an efficient diagnosis of dengue-associated liver involvement, enabling the early identification and management of severe dengue.

An Observational Study to Find the Association of Viral Load, NS1 Antigen, IgG Antibody, and Other Laboratory Parameters With the Outcome of Dengue Patients in Eastern India

Background Dengue, the mosquito-borne febrile disease caused by the dengue virus, has become one of the major concerns of public health. It may present with only fever, or there may be a hemorrhagic manifestation or septic shock. As there is no specific treatment for dengue, early detection of the disease, assessment of progression, and prediction of outcome by studying the laboratory markers will help guide the management of cases and lower morbidity and mortality. Methodology This clinico-observational study was conducted at the Department of Microbiology in a tertiary care hospital in Kolkata, India, from February 2020 to August 2022 to determine the outcome of dengue patients in correlation with viral load, NS1 antigen, IgM and IgG antibodies, ferritin level, platelet count, and other laboratory parameters. Results Out of 316 samples from fever patients, 103 (32.5%) were NS1 antigen reactive. We followed up the dengue patients (n = 103) for 15 days and divided them into three groups according to their duration of symptoms (group A suffered for ≤5 days, group B for 5 to 10 days, and group C for >10 days) and per the WHO classification of disease severity, namely dengue without warning signs (DOS), dengue with warning signs (DWS), and severe dengue (SD). Based on severity, 65 (63.1%) patients had DOS, whereas 31 (30.09%) patients had DWS, and seven (6.79%) patients had SD. Secondary infection was present in 83.33% of patients in group C, 71% of DWS cases, and 57% of SD cases, which positively correlates with liver enzymes, viral load (mean value 102195 in secondary infection vs. 1195 copies/10 µl in primary infection), and negatively correlates with platelet counts (mean value 60,213 in secondary infection vs. 1,25,516 in primary infection). Patients in group C had higher liver enzymes, a lower platelet count, and a higher initial viral load than groups A and B. Similarly, SD cases had a higher ferritin level (9215 ug/l), a lower platelet count (mean value 23,250), and a higher initial viral load (mean value 2,74,257 copies/10 µl). An increase in hematocrit value considering the peak value and its baseline value is an important marker for disease severity rather than its absolute value. Conclusion Poor outcome of dengue infection, i.e., an increase in the duration of symptoms and disease severity depends on concurrent associations between high serum ferritin, increased hematocrit level, thrombocytopenia, secondary infection, increasing liver enzymes, and increased initial viral load.

Changes in the Liver Function and Hematological Parameters in Dengue Patients at a Tertiary Care Center: A Descriptive Cross-sectional Study

INTRODUCTION

Liver is most commonly affected in dengue often resulting in changes in the liver function test parameters. Alterations in hematological parameters are also reported which could serve as early prognostic markers especially in resource limited settings where serological tests for the diagnosis of dengue is not available. This study aims to analyze liver function test and hematological parameter changes in dengue infected patients.

METHODS

A descriptive cross-sectional study was conducted from December 2022 to October 2023 in serologically dengue positive patients. Liver function parameters and blood parameters were analyzed from 220 patients. The purposive sampling technique was employed during the selection of participants.

RESULTS

Out of 220 study participants, 113 (51.36%) were males and 107 (49.64%) were females. The median age of the participants was 35 years (IQR: 26 - 48 years). Elevated serum AST and ALT levels were present in 121 (55%) and 80 (36.36%) of the participants respectively. Thrombocytopenia and leukopenia were observed in 92 (41.82%) and 88 (40%) of the study participants respectively. The median hemoglobin level was 14.4 (IQR: 13-15.47) g/dl. Low hemoglobin level was found in 31 (14.09%) participants. The median red blood cell count was 4.91 (IQR: 4.49 - 5.28) millions/mm3 with decreased red blood cell count noted in 27 (12.27%) participants.

CONCLUSIONS

Increased serum transaminases levels, thrombocytopenia and leukopenia are common laboratory findings in dengue patients.

The continuum of liver injury with severity of dengue fever: A retrospective observational study

BACKGROUND

Dengue is a major international health concern prevalent in tropical and sub-tropical countries. There are a paucity of studies on the relationship of hepatic complications with inflammatory parameters in dengue infection.

METHODS

Single-centre observational study was conducted at the tertiary care centre in North India. Patients (>12 years) diagnosed with dengue infection between August and November 2021 were enrolled in the study. The frequency of hepatic derangements and their associations with inflammatory severity was analysed.

RESULTS

Based on the clinical symptoms, 170 patients were classified into three categories, namely, dengue fever, warning dengue and severe dengue. Higher incidence of liver dysfunction was observed in severe dengue patients with median values of aspartate aminotransferase (AST) (3051 U/L, p < 0.001), alanine aminotransferase (ALT) (1792 U/L, p = 0.009), alkaline phosphatase (172 U/L, p = 0.001), T.Bil (34.2 µmol/L, p < 0.001), albumin (30 g/L, <0.001), and gamma-glutamyl transferase (152 U/L, p < 0.001) along with inflammatory marker C-reactive protein (CRP) (43 mg/dL, p < 0.001) highly deranged, in comparison to patients with/without warning signs. Median levels of CRP were found to be positively and significantly correlated with the median levels of AST and ALT (p < 0.05, r = 0.99) in all three categories of dengue patients. Liver injury was noted in 107 (63%) of the cohort, and mixed type of liver injury involving both hepatocellular and cholestatic patterns was observed as the most common type of injury (n = 50, 29.4%). Liver injury correlated with the severity of dengue illness as about 85% of severe dengue patients had significant liver injury (p = 0.014).

CONCLUSION

In dengue patients, the association of the liver injury with inflammatory severity suggests that the mechanism of liver injury may be related to inflammatory response apart from the hepatotropic nature of the virus.

Genetic Analysis of Dengue Virus in Severe and Non-Severe Cases in Dhaka, Bangladesh, in 2018-2022

Dengue virus (DENV) infections have unpredictable clinical outcomes, ranging from asymptomatic or minor febrile illness to severe and fatal disease. The severity of dengue infection is at least partly related to the replacement of circulating DENV serotypes and/or genotypes. To describe clinical profiles of patients and the viral sequence diversity corresponding to non-severe and severe cases, we collected patient samples from 2018 to 2022 at Evercare Hospital Dhaka, Bangladesh. Serotyping of 495 cases and sequencing of 179 cases showed that the dominant serotype of DENV shifted from DENV2 in 2017 and 2018 to DENV3 in 2019. DENV3 persisted as the only representative serotype until 2022. Co-circulation of clades B and C of the DENV2 cosmopolitan genotype in 2017 was replaced by circulation of clade C alone in 2018 with all clones disappearing thereafter. DENV3 genotype I was first detected in 2017 and was the only genotype in circulation until 2022. We observed a high incidence of severe cases in 2019 when the DENV3 genotype I became the only virus in circulation. Phylogenetic analysis revealed clusters of severe cases in several different subclades of DENV3 genotype I. Thus, these serotype and genotype changes in DENV may explain the large dengue outbreaks and increased severity of the disease in 2019.

Real-World Evidence for COVID-19 Delta Variant's Effects on the Digestive System and Protection of Inactivated Vaccines from a Medical Center in Yangzhou, China: A Retrospective Observational Study

Background

Coronavirus disease 2019 (COVID-19) is rapidly disseminated worldwide, and it continues to threaten global public health. Recently, the Delta variant has emerged as the most dreaded variant worldwide. COVID-19 predominantly affects the respiratory tract, and studies have reported the transient effects of COVID-19 on digestive system function. However, the relationship between the severity of the Delta variant and digestive system function remains to be investigated. Additionally, data on the ability of the inactive Chinese vaccines (Sinovac or Sinopharm) to protect against the Delta variant or COVID-19-induced gastrointestinal symptoms in the real world are insufficient. Thus, the present retrospective observational study first attempted to use the total gastrointestinal symptom rating scale scores (GSRS) to quantify the possible changes in digestive system functions following the Delta variant infection in the early stage. In addition, the study discusses the potential of inactivated vaccines in preventing severe or critical symptoms or Delta variant-induced digestive system dysfunction.

Methods

To evaluate the difference between mild illness group, moderate illness group, and severe or critical illness group, analysis of variance (ANOVA) was employed to compare the three groups' total gastrointestinal symptom rating scale scores (GSRS). A chi-squared test was used to compare the differences in the ratio of the abnormal biochemical measurements among the three groups first. Then, the percentage of the vaccinated population was compared among the three groups. Additionally, the ratio of the abnormal serum markers between the vaccinated and nonvaccinated cohorts was compared. A P value < 0.05 was considered statistically significant.

Results

Significant differences were observed in the abnormal ratio of alanine aminotransferase (ALT), total bilirubin (TBIL), direct bilirubin (DBIL), lactate dehydrogenase (LDH), and Interleukin 6 (IL-6) ratio among the three groups (P < 0.05). Additionally, no significant difference was observed in the abnormal serum markers ratio between day 14 and day 21 after treatment (P > 0.05). A significant difference was observed in the total GSRS scores among the three groups and the ratio of the vaccinated population among the three groups (P < 0.05). A significant difference was observed in the ratio of the abnormal serum ALT and AST levels between the vaccinated and nonvaccinated cohorts (P < 0.05).

Conclusions

In summary, serum AST, DBIL, LDH, and IL-6 levels are potential markers for distinguishing severe or critical patients in the early stage of the Delta variant infection. Additionally, changes in the levels of these serum makers are transient, and the levels can return to normal after treatment. Furthermore, severe gastrointestinal discomfort was significantly more prevalent in patients with severe or critical diseases and should thus be considered in patients diagnosed with Delta variant infection. Finally, inactivated vaccines may prevent severe or critical symptoms and Delta variant-induced liver dysfunction. Vaccination programs must be promoted to protect public health.