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Published on: September 10, 2021
Gastrointestinal Infection Could Be New Focus for Coronavirus Diagnosis
Massimiliano Cipriano1, Enzo Ruberti2, Andrea Giacalone3
1Department of Laparoscopic Surgery, Umberto I General Hospital, Medical School Sapienza University, Rome, ITA.
Insights
Gastrointestinal symptoms, like diarrhea, can be an early sign of COVID-19. The virus may be present in stool even after respiratory tests are negative, suggesting fecal-oral transmission risks.
Area of Science:
- Virology
- Gastroenterology
- Infectious Diseases
Background:
- The COVID-19 pandemic, caused by SARS-CoV-2, is primarily known as a respiratory illness.
- Gastrointestinal (GI) complications have been noted in previous viral respiratory illnesses like SARS and MERS.
- Emerging evidence suggests GI symptoms can be an initial presentation of COVID-19.
Purpose of the Study:
- To highlight the emerging role of gastrointestinal complications in COVID-19.
- To discuss the potential for fecal-oral transmission of SARS-CoV-2.
- To emphasize the significance of fecal testing in COVID-19 patient management.
Main Methods:
- Review of case series and studies on hospitalized COVID-19 patients.
- Analysis of polymerase chain reaction (PCR) testing results from stool and respiratory samples.
- Consideration of guidelines from the Centers for Disease Control and Prevention (CDC).
Main Results:
- Approximately 10% of hospitalized COVID-19 patients presented initially with GI symptoms (diarrhea, nausea, abdominal pain).
- SARS-CoV-2 RNA has been detected in stool samples, sometimes persisting after respiratory samples are negative.
- Up to 24% of patients may remain positive for the virus in stool after respiratory clearance.
Conclusions:
- Gastrointestinal symptoms are an important, sometimes initial, manifestation of COVID-19.
- The presence of SARS-CoV-2 in stool indicates a potential for fecal-oral transmission.
- Routine fecal rRT-PCR testing for SARS-CoV-2 in patients is recommended, drawing parallels with SARS management.
Abstract:
It's not news to tell you that the coronavirus, known as COVID-19, is a worldwide pandemic. The initial outbreak of this novel virus in Wuhan in the Hubei province of China, first described in December 2019, has since moved on to being declared a pandemic by the World Health Organization. The classic description of COVID-19 is a respiratory illness that manifests with fever, dry cough, and dyspnea on exertion. However, gastrointestinal (GI) complication of COVID-19 is emerging as well. This was observed with similar viral respiratory illnesses, such as severe acute respiratory syndrome (SARS), which emerged in 2003, and the Middle East respiratory syndrome (MERS), which emerged in 2012. In a recently published, single-center case series of 138 consecutive hospitalized patients with confirmed COVID-19, investigators reported that approximately 10% of patients initially presented with GI symptoms, prior to the subsequent development of respiratory symptoms. Common and often very subtle symptoms included diarrhea, nausea, and abdominal pain, with a less common symptom being nonspecific GI illness. New studies are expanding our understanding of the possible fecal transmission of COVID-19. Assessment by polymerase chain reaction (PCR) has provided evidence of the virus in the stool and the oropharynx outside the nasopharynx and respiratory tract. Virus in the stool may be evident on presentation and last throughout the course of illness resolution for up to 12 days after the respiratory virus evidence is gone. In fact, in one of the most recent studies looking at 73 patients, approximately 24% remained positive in their stool for evidence of the virus, though not necessarily infection, after showing negative in respiratory samples. The Centers for Disease Control and Prevention (CDC) recommends that after two negative respiratory tests separated by ≥ 24 hours, patients can be dismissed from having transmissibility infection risk for COVID-19. The potential for fecal-oral transmission of COVID-19 needs to be strongly considered. Considering these cases and the lessons from SARS, many authors recommend that real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from feces should be performed routinely in SARS-CoV-2 patients.
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