Infectious Diarrhea Caused by Nocardia farcinica in a 19-Month-Old Child

Jing Yang,1,* Dixia Hu,2,* Kaige Yin,3 Fang Li,4 Dongyan Shi5 1Hebei Provincial Center for Clinical Laboratories, The Second Hospital of Hebei Medical University, Shijiazhuang, People’s Republic of China; 2Department of Clinical Lab, Zhangjiakou First Hospital, Zhangjiakou, People’s Republic of China; 3Department of Gastroenterology, The Second Hospital of Hebei Medical University, Shijiazhuang, People’s Republic of China; 4Department of Pediatrics, The Second Hospital of Hebei Medical University, Shijiazhuang, People’s Republic of China; 5Department of Clinical Lab, The Second Hospital of Hebei Medical University, Shijiazhuang, People’s Republic of China*These authors contributed equally to this workCorrespondence: Dongyan Shi, Email shidongyan73@126.comBackground: Nocardia farcinica, a pathogen known for its strong pathogenicity, is frequently implicated in skin, central nervous system, and lung infections among immunosuppressed hosts, while intestinal nocardiosis is rare. We report the case of infectious diarrhea caused by N. farcinica in a child.Case Presentation: A 19-month-old female child was admitted to the hospital with fever and diarrhea after the consumption of oranges. The etiological agent responsible for the diarrhea was identified through the examination of fecal smears using weak acid-fast staining and conducting fecal cultures. Whole-genome sequencing was employed to analyze the causative gene. Subsequent to a 5-day treatment regimen with amoxicillin-clavulanate at a dosage of 30 mg/kg every 12 hours, the child’s condition improved significantly, leading to an uncomplicated discharge.Conclusion: This case illustrates the presence of intestine virulence factors in N. farcinica capable of causing diarrhea. The utilization of weak acid-fast staining in the examination of fecal smears is crucial for the accurate diagnosis of infectious diarrhea caused by Nocardia spp.Keywords: Nocardia farcinica, diarrhea, virulence factors