Clinicopathologic Features of Varicella Zoster Virus Infection of the Upper Gastrointestinal Tract

Infectious Disease Pathology of the Gastrointestinal Tract: Diagnosing the Challenging Cases

Infectious diseases of the GI tract mimic a variety of other GI diseases, including chronic idiopathic inflammatory bowel disease and ischemia. It can be challenging to identify pathogens in tissue sections as well, as many trainees are not exposed to infectious disease pathology other than in the context of microbiology. Our ability to diagnose infections in formalin fixed, paraffin embedded material has grown exponentially with the advent of new histochemical and immunohistochemical stains, as well as more options for molecular testing. Correlating these diagnostic techniques with morphology has led to increasing understanding of the histologic patterns that are associated with specific pathogens.

Visceral disseminated varicella-zoster virus infection in an immunocompetent host

Varicella-zoster virus (VZV) can cause visceral disseminated VZV infection in immunocompromised patients. We experienced visceral disseminated VZV infection in an immunocompetent host. A 78-year-old woman visited our hospital complaining of abdominal pain that had persisted for 7 days. On day 3 after admission, a skin rash with blisters appeared mainly on her head and trunk that was diagnosed as generalized zoster via rapid skin VZV diagnostic kit. Esophagogastroduodenoscopy showed gastric erosions, and VZV was detected by real-time polymerase chain reaction testing of the gastric mucosal biopsy specimen. Computed tomography imaging also revealed pancreatitis and colitis, and she was diagnosed as having visceral disseminated VZV infection involving multiple organs. She was treated with acyclovir intravenously, after which her skin rash and abdominal pain disappeared. Because visceral disseminated VZV infection can occur in immunocompetent patients, this disease should be considered in patients with unexplained inflammatory lesions of the gastrointestinal tract or pancreas.

The Impact of Human Herpesviruses in Clinical Practice of Inflammatory Bowel Disease in the Era of COVID-19

Human herpesviruses (HHVs): herpes simplex virus (HSV) types 1 (HSV-1) and 2 (HSV-2), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), HHV-6, HHV-7, and HHV-8, are known to be part of a family of DNA viruses that cause several diseases in humans. In clinical practice of inflammatory bowel disease (IBD), the complication of CMV enterocolitis, which is caused by CMV reactivation under disruption of intestinal barrier function, inflammation, or strong immunosuppressive therapy, is well known to affect the prognosis of disease. However, the relationship between other HHVs and IBD remains unclear. In the transplantation field, reactivation of other viruses, such as HHV-6, could cause colitis under immunosuppressed condition. Recent research revealed that combined infection of some HHVs could be a risk factor for colectomy in patients with ulcerative colitis. This suggests that it would be important to clarify HHV behavior in the treatment for patients with IBD, especially in those under immunosuppressive therapies. Looking at the relationship with recently emerged novel coronaviruses (SARS-CoV-2), there are reports describe that SARS-CoV-2 might induce reactivation of HSV-1, EBV, VZV (herpes zoster), and HHV-6/7. If SARS-CoV-2 infection becomes common, vigilance against HHV reactivation may become more crucial. In this review, we discuss the impact of HHVs in clinical practice of inflammatory bowel diseases, especially during the SARS-CoV-2 pandemic.