Acute cytomegalovirus hepatitis in immunocompetent host

Acute murine cytomegalovirus infection boosts cell-type specific response and lipid metabolism changes in the liver of infant mice

Introduction

Human cytomegalovirus (HCMV) infection in infants can lead to severe diseases, including neonatal hepatitis. The single-cell dimensional changes in immune cells after the initial CMV infection remain elusive, as do the effects of CMV infection on hepatic lipid metabolism.

Methods

We employed single-cell RNA-sequencing to investigate the changes in liver cell types and immune responses in infant mice following murine CMV (MCMV) infection. Additionally, we examined alterations in protein expression profiles related to lipid metabolism in hepatocytes and the role of the key transcription factor PPAR-γ in hepatocytes during CMV infection.

Results

Our study revealed that MCMV infects most liver cell types in infant mice, leading to an increase in the proportion of proliferating CD8 effector T cells and a subset of Nos2+ monocytes, potentially playing an essential role in early anti-viral responses. Furthermore, MCMV infection resulted in altered protein expression of lipid metabolism in hepatocytes. Knocking down the transcription factor PPAR-γ in hepatocytes effectively inhibited CMV infection.

Discussion

Our findings underscore the immune system's response to early-stage MCMV infection and the subsequent impact on hepatic lipid metabolism in infant mice. This research provides new insights into the mechanisms of CMV infection and could pave the way for novel therapeutic strategies.

Cytomegalovirus Hepatitis in an Immunocompetent Patient: A Cause of Fever of Unknown Origin

Acute hepatitis is most often self-resolving and a benign condition that rarely requires any anti-viral drugs. In immunocompromised patients (HIV-infected patients and transplant recipients), the morbidity and mortality associated with cytomegalovirus (CMV) infection have been extensively reported in the medical literature. We are describing a rare case of acute severe cytomegalovirus hepatitis in an immunocompetent host. In immunocompetent individuals, in most cases, it causes a subclinical infection and hence doesn't require an anti-viral agent for treatment. Our patient was unique because it presented with clinically severe hepatitis and was uncharacteristically treated with the use of antiviral medications.

The use of microRNA by human viruses: lessons from NK cells and HCMV infection

Depending on ethnicity and on social conditions, between 40 and 90 % of the population is infected with human cytomegalovirus (HCMV). In immunocompetent patients, the virus may cause an acute disease and then revert to a state of latency, which enables its coexistence with the human host. However, in cases of immunosuppression or in neonatal infections, HCMV can cause serious long-lasting illnesses. HCMV has developed multiple mechanisms in order to escape its elimination by the immune system, specifically by two killer cell types of the adaptive and the innate immune systems; cytotoxic T lymphocytes (CTL) and natural killer (NK) cells, respectively. Another fascinating aspect of HCMV is that like other highly developed herpesviruses, it expresses its own unique set of microRNAs. Here, we initially describe how the activity of NK cells is regulated under normal conditions and during infection. Then, we discuss what is currently known about HCMV microRNA-mediated interactions, with special emphasis on immune modulation and NK cell evasion. We further illustrate the significant modulation of cellular microRNAs during HCMV infection. Although, the full target spectrum of HCMV microRNAs is far from being completely elucidated, it can already be concluded that HCMV uses its "multitasking" microRNAs to globally affect its own life cycle, as well as important cellular and immune-related pathways.

A young patient with multisystem complications after cytomegalovirus infection

We are describing a case of an 18-year-old male patient with cytomegalovirus (CMV) associated guillain-barre syndrome (GBS) who presented with an acute onset of generalized weakness and numbness in the extremities, dysphagia, and facial diplegia, followed by respiratory failure, which led to mechanical ventilation. He had positive immunoglobulin G and immunoglobulin M antibodies against CMV, and CMV polymerase chain reaction was positive with <2000 copies of deoxyribonucleic acid. Human immunodeficiency virus test was negative. He received a course of ganciclovir, intravenous immunoglobulin, and plasmapheresis. After improving from acute episode, patient was transferred to a rehabilitation facility for physical and occupational therapy. At the rehabilitation facility, he exhibited signs of acute abdomen with pain in the left upper quadrant secondary to peritonitis from dislodged gastrostomy tube and underwent exploratory laparotomy. During the hospital course he was found to have splenic infarct and colitis on the computed tomography of abdomen. This case showed an immunocompetent young patient with multisystem complications including guillain-barre syndrome (GBS), splenic infarct, hepatitis, and colitis due to CMV.

Acute cytomegalovirus hepatitis in an immunocompetent host

A 52-year-old woman presented with a 1-week history of recurrent fevers and joint pains accompanied by abdominal and low back discomfort. She has a history of hypoparathyroidism and is on calcium supplements. Physical examination revealed fever and tachycardia. The rest of the examination was normal. Laboratory tests showed newly increased transaminase activity. Serum bilirubin and prothrombin time were normal. She was admitted for evaluation of acute hepatitis. Serology for hepatitis A, B, C and HIV were negative. Her serum acetaminophen and alcohol were undetected. Abdominal imaging was normal. Cultures were sterile. Additional tests for uncommon viral hepatitis included herpes simplex virus, cytomegalovirus and Epstein-Barr virus. Liver biopsy revealed non-specific inflammation. Subsequently, cytomegalovirus serology showed an IgM positive and negative IgG titre. Cytomegalovirus DNA qualitative PCR was also positive. No antiviral medication was given. She continued to have intermittent daily fever but reported no associated symptoms. She was discharged 9 days after admission in stable condition per her request with the advice to follow-up in the clinic in 1 week. Her serum hepatic profile returned to normal and she reported no more episodes of fever. Repeated titres of cytomegalovirus serology showed seroconversion.

An immunocompetent adult patient with hepatitis and guillain-barré syndrome after cytomegalovirus infection

OBJECTIVES

It is to describe an immunocompetent adult patient with hepatitis and Guillain-Barré syndrome (GBS) after Cytomegalovirus (CMV) infection. In the initial course of the diagnosis and treatment, CMV infection was ignored.

CASE REPORT

A 19-year-old Chinese girl complained of fatigue with pain and numbness of the limbs, with abnormal liver function. She was diagnosed as a case of GBS based on history, clinical findings and auxiliary examinations. On day 13 of admission, her liver function was still abnormal. So CMV was recommended to examine. CMV hepatitis was diagnosed on positive serum anti-CMV IgG and IgM antibodies. The case was improved only with intravenous immunoglobulin therapy, without the use of antiviral therapy.

CONCLUSIONS

This case showed an immunocompetent adult patient with hepatitis and GBS induced by CMV. The physicians should take into account multi-system involvement of severe CMV infection.