Differences in Characteristics Between Patients Who Met or Partly Met the Diagnostic Criteria for Food Protein-Induced Enterocolitis Syndrome (FPIES).

BACKGROUND: Some patients with food protein-induced enterocolitis (FPIES)-like allergy do not completely fulfill the diagnostic criteria of the international consensus guideline for FPIES. However, it is unclear whether such FPIES-like patients represent a completely different population from FPIES. OBJECTIVE: This study aimed to clarify differences in characteristics between patients with FPIES who fully met diagnostic criteria and those who partly met them. METHODS: This was a cross-sectional study using data at the time of registration in multicenter, prospective studies of patients with FPIES in Japan. Children who had delayed emesis within 1 to 4 hours and/or diarrhea within 5 to 10 hours after ingestion of food were recruited between March 2020 and February 2022. We examined their compatibility with the diagnostic criteria of the international consensus guideline and their detailed clinical characteristics, including trigger foods, the serving size that elicited symptoms, and antigen-specific IgE antibody titers. RESULTS: Of the 225 patients with FPIES, 140 fully met the diagnostic criteria whereas 79 patients did not fully meet them but demonstrated reproducible symptoms. The frequencies of pallor, lethargy, and diarrhea were significantly higher in those who met the criteria fully, whereas the age at onset, trigger foods, comorbidity, and perinatal information were comparable. Analysis of patients with FPIES to hen's egg revealed significantly higher levels of egg white- and egg yolk-specific IgE in patients who partly met criteria, whereas the serving size eliciting symptoms was comparable. CONCLUSIONS: Patients who partly met the diagnostic criteria may have a milder phenotype of FPIES, but this needs to be validated in further studies using biomarkers reflecting the pathophysiology.

Descending necrotizing mediastinitis secondary to retropharyngeal abscess in a child.

We report herein of a 6-year-old boy with descending necrotizing mediastinitis (DNM) secondary to retropharyngeal abscess, who was successfully treated by the administration of antibiotics. DNM is very rare in children, and surgical drainage of the mediastinum is recommended in adult patients. DNM should be recognized as a severe complication of an oropharyngeal infection in children, and early and accurate diagnosis is important in ensuring appropriate clinical management.

[Methotrexate-induced interstitial pneumonitis in a child with acute lymphoblastic leukemia].

We report a case of 5-year-old boy with acute lymphoblastic leukemia who developed interstitial pneumonitis induced by methotrexate (MTX). The patient was hospitalized with fever, cough, dyspnea and hypoxemia during maintenance treatment with low dose MTX and 6-mercaptopurine. A diagnosis of MTX pneumonitis was made based on the clinical findings, viral and serologic studies, negative microbiology and the radiological features. The patient recovered after cessation of the MTX treatment. Interstitial pneumonitis caused by MTX is well-recognized and the prevalence has been estimated to be 0.3-7.5% among patients with adult rheumatoid arthritis. However, there are few reports in the literature regarding this adverse effect in patients with leukemia. Furthermore, very few cases of childhood leukemia have been reported regarding MTX induced interstitial pneumonitis. Physicians should be aware of this rare complication during maintenance treatment with weekly low dose MTX for acute lymphoblastic leukemia in children.