• CEUS is a feasible approach for SLN identification and characterisation. • The enhancement patterns on CEUS can be helpful in recognising metastasised SLNs. • Homogeneous enhancement pattern has the highest negative-predictive value.

Rationale:Brucellosis is a multisystem infection found worldwide that has a broad range of characteristics, which range from acute fever and hepatomegaly to chronic infections that most commonly affect the central nervous system, cardiovascular system, or skeletal system. Gastrointestinal and splanchnic artery involvements in brucellosis are relatively uncommon.Patient concerns:We report a case of brucellosis in an adolescent presenting as intermittent abdominal pain, diarrhea, and fever, with intestinal tract involvement. And stenosis of the celiac artery and the superior mesenteric artery was found after exposed to risk factors of Brucella infection. Splanchnic vessels stenosis and an endothelial lesion may exacerbate the prevalent symptom of abdominal pain, as a form of colic pain, occurring after eating.Diagnoses:The patient was diagnosed as brucellosis. The narrowing of the SMA and CA was suspected to be vasculitis secondary to the brucellosis.Interventions:The patient was treated with minocycline and rifampicin for 12 weeks totally.Outcomes:The gastrointestinal manifestations of brucellosis recovered rapidly under intensive treatment. However, follow-up imaging revealed that the superior mesenteric artery and celiac artery stenosis was unimproved.Lessons:In brucellosis, gastrointestinal manifestations may be the only observable features of the disease. Splanchnic arterial stenosis is a rare complication of brucellosis. Sonography and computed tomography may be useful for both diagnosis and follow-up.

Rationale:Primary lymphoma that arises from the intestine is an uncommon malignant tumour, while intestinal fistula caused by primary lymphoma is even rarer. Non-specific clinical performance makes early diagnosis difficult, although imaging modalities might play an essential role in the detection of intestinal fistula.Patient concerns:Patient 1: A 60-year-old male hospitalized with diarrhoea and abdominal pain for seven months underwent computed tomography enterography (CTE) that demonstrated ileum internal fistula and ileac-sigmoid colon fistula. Ultrasound (US) showed small intestinal wall thickened and development of a fistula of the sigmoid colon due to malignance. Patient 2: A 43-year-old male presented with abdominal pain and diarrhoea lasting one year. US revealed a fistula between the sigmoid colon and the ileum, and CTE showed that the wall of the partial sigmoid colon was abnormally thickened and enhanced with an ileal-sigmoid fistula that strongly suggested the diagnosis of lymphoma.Diagnoses:Both the two patients were diagnosed as intestinal fistula caused by primary non-Hodgkin's intestinal lymphoma.Interventions:The patient 1 underwent surgery followed by chemotherapy. The patient 2 accepted chemotherapy.Outcomes:Two patients’ general conditions remained stable and the imaging revealed no recurrence after follow-up of about 12 months.Lessions:Cross-sectional imaging, such as US and CT, plays an essential role in intestinal lymphoma fistula diagnosis.