Asymptomatic Meckel’s diverticulum cases are not uncommon, leading to diagnostic difficulties in cases of atypical presentations with only gastrointestinal symptoms other than bloody stool. A nine-year-old boy diagnosed as having cyclic vomiting because of recurrent abdominal pain and vomiting for 6 months was referred to our institute and hospitalized due to worsening symptoms. After admission, abdominal ultrasonography showed the multiple concentric ring sign and a pseudokidney sign at the lower ileum, leading to the diagnosis of ileo-ileal intussusception, but the gastrointestinal symptoms and ultrasonic findings disappeared spontaneously. Transanal, double-balloon, intestinal endoscopy demonstrated a pedunculated polyp-like structure, and surgical resection was performed. An inverted diverticulum was found in the resected intestinal lumen, and ectopic gastric mucosa was identified histologically, leading to the diagnosis of inverted Meckel’s diverticulum. In pediatric cases involving periodic attacks of vomiting and abdominal pain, unnecessary emergent surgery could be avoided by cautious imaging evaluation and consideration of ileo-ileal intussusception with advanced lesions of an inverted Meckel’s diverticulum as a differential diagnosis, without facilely diagnosing cyclic vomiting. In addition, previous reports of inverted Meckel’s diverticulum were reviewed, and the results were compared between adult and pediatric groups in each category.

Background Granulomatosis with polyangiitis (GPA) is a syndrome of refractory vasculitis involving the upper respiratory tract, lungs, kidneys, and systemic small and medium-sized arteries that affects all age groups. No pediatric case with a bloody pericardial effusion resulting in cardiac tamponade and co-existing hematochezia has been reported. Case presentation A 14-year-old boy was referred for evaluation of prolonged fever, chest pain, and intermittent hematochezia. Diagnostic imaging showed a prominent pericardial effusion. Immediately after admission, his systolic blood pressure decreased. Emergent pericardiocentesis resulted in aspiration of a massive amount of bloody pericardial fluid. This was diagnosed as cardiac tamponade because his blood pressure recovered immediately after the drainage. The patient had an elevated serine proteinase 3-anti-neutrophil cytoplasmic antibody (PR3-ANCA) level on serological examination. Head MRI showed thickening of nasal and sinusoidal mucosa and a cystic mass in the left sphenoid sinus. After ruling out malignancy based on the cytology of the effusion, chest MRI, and gallium scintigraphy, total colonoscopy showed multiple irregular-shaped aphthae from the right transverse colon to the cecum on the contralateral side of the mesenteric attachments. Biopsy specimens of aphthous lesions confirmed necrotizing granulomatous inflammation. A diagnosis of GPA was made based on these findings, and oral prednisolone (PSL) and azathioprine were started. The hematochezia disappeared rapidly, and no recurrence of pericardial effusion was seen after PSL tapering was completed. The PR3-ANCA level decreased into the normal range immediately after the initial therapy. Conclusions Pericarditis is a common cardiac complication of GPA, but there have been no reports of resultant cardiac tamponade. This is the first case of pediatric GPA with cardiac and gastrointestinal complications preceding the common symptoms such as respiratory or renal symptoms. A case of pediatric GPA with hematochezia is also extremely rare. In conclusion, serial measurement of ANCA levels is important in patients with persistent fever and bloody stool, such as in inflammatory bowel disease, to make the diagnosis of a vasculitic syndrome.

Background Granulomatosis with polyangiitis (GPA) is a syndrome of refractory vasculitis in the upper respiratory tract, lungs, kidneys, and systemic small and medium-sized arteries; adults and children have similar courses. A pediatric GPA case with a preceding bloody pericardial effusion, which caused cardiac tamponade, and bloody stool has not been reported. Case presentation: A 14-year-old boy was referred for the evaluation of prolonged fever. He had chest pain and bloody stools, and diagnostic imaging showed a pericardial effusion. Immediately after admission, his systolic blood pressure decreased (85/70 mmHg), and pericardiocentesis was performed, with aspiration of approximately 500 mL of bloody pericardial fluid. Because pericardiocentesis increased the blood pressure (115/65 mmHg), the cause of the blood pressure decrease was diagnosed as cardiac tamponade. Because the pericardial fluid cytology was negative for malignant disease, as were chest MRI and gallium scintigraphy, colonoscopy was performed and showed multiple irregular-shaped aphthae from the right transverse colon to the cecum on the contralateral side of the mesenteric attachments, and a biopsy of the aphthous region showed necrotizing granulomatous inflammation. The patient also had an elevated serine proteinase 3-anti-neutrophil cytoplasmic antibody (PR3-ANCA) level (141 IU/mL) on serological examination. Head MRI showed thickening of nasal and sinus mucosa and a cystic mass in the left sphenoid sinus. Therefore, GPA was diagnosed based on these findings, and treatment with oral prednisolone (PSL) and azathioprine was started. After the treatment, the bloody stool disappeared, and there was no recurrence of pericardial effusion even after completing PSL tapering, and the PR3-ANCA level was maintained in the normal range. Conclusions Although pericarditis is a common cardiac complication of GPA, there have been no previous reports of cardiac tamponade due to pericarditis. This is the first case of a pediatric patient with cardiac and gastrointestinal complications preceding the main symptoms, including upper and lower respiratory tract and renal symptoms, although cases of GPA with bloody stools are extremely rare. In conclusion, the sequencing of measuring ANCA levels appears important assuming the vasculitic syndrome as one of differential diseases causing persistent fever and bloody stool including such as the inflammatory bowel disease.