Abstract
BACKGROUND: Enteric zoster, a rare herpes zoster manifestation, occurs when varicella-zoster virus (VZV) reactivates enteric nervous system neurons, leading to abdominal pain and gastrointestinal symptoms without a cutaneous rash. Due to absence of the skin lesion, diagnosis is challenging. Recently, salivary VZV DNA polymerase chain reaction (PCR) has been suggested as a diagnostic test for herpes zoster. This investigation aimed to assess the prevalence of salivary VZV DNA positivity among patients with acute abdominal pain and to evaluate its diagnostic value by comparing PCR results in patients undergoing intra-abdominal surgery. METHODS: We prospectively enrolled adult patients presenting to the emergency department with acute abdominal pain between June 2023 and April 2024 at a community-based university hospital. The patients underwent detailed history reviews, blood tests, and abdominal computed tomography (CT). Salivary VZV DNA PCR was performed. Additionally, to investigate subclinical VZV reactivation under acute gastrointestinal stress, salivary VZV DNA PCR was conducted within 48 hour post-abdominal surgery as a control. Enteric zoster was inferred in individuals exhibiting positive salivary VZV DNA, identified through real-time PCR. RESULTS: In total, 101 patients with abdominal pain were enrolled. Positive salivary VZV DNA PCR results were found in 5 (5.0%) patients. Two patients had acute cholecystitis, one had acute appendicitis, one had acute pancreatitis, and the remaining patient had no identifiable cause of abdominal pain on CT. All 19 patients tested negative for salivary VZV DNA PCR post-abdominal surgery within 48 hours. CONCLUSION: About 5% of patients experiencing acute abdominal pain exhibited positive salivary VZV DNA PCR findings, indicating that enteric zoster may be a potential factor in both recognized and unidentified causes of acute abdominal pain. Further research is needed to determine if antiviral therapy guided by salivary VZV DNA PCR results can alleviate abdominal pain in this patient population.