Misdiagnosed periappendiceal and intestinal tuberculosis during the COVID-19 pandemic.

Introduction and importance: The coronavirus disease 2019 (COVID-19) was first reported in Wuhan, Hubei Province, China. It mainly involves the respiratory system, causing fever, cough, chest tightness, and other symptoms. However, when combined with other common or rare diseases, such as appendicitis and intestinal tuberculosis (TB), it can cause other systemic lesions, thus making the original disease lose its specific clinical manifestations. This case highlights the importance of early identification and clinical precision medicine diagnosis and treatment. Case presentation: A young woman presented with intermittent pain and discomfort in the right lower quadrant. Ultrasonography suggested appendicitis with a peripheral abscess. The nucleic acid test of COVID-19 was positive, and the chest computed tomography scan showed pulmonary involvement. She was sent for surgery. Postoperative body temperature increased regularly, and the TB T-cell test was positive. Clinical discussion: Multiple infections caused by common bacteria, pandemic virus, and specific mycobacterium TB cause a series of nonspecific clinical manifestations, which brings challenges to clinical diagnosis and treatment. Therefore, when facing a complex infection case, the authors should consider the possibility of multiple infections and give targeted treatment for the pathogens. Conclusions: During the epidemic of COVID-19, the incidence of intestinal TB is relatively low, which is easy to be overlooked and misdiagnosed, especially in the case of appendicitis. Therefore, clinicians must be highly vigilant in the diagnosis process to avoid missed diagnosis or misdiagnosis, so as to provide the best diagnosis and treatment plan.