Markedly Elevated Procalcitonin in Food Protein Induced Enterocolitis Syndrome.

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated gastrointestinal food allergy. Some studies have reported that FPIES was associated with elevated C-reactive protein (CRP). However, the number of reports on the relationship between FPIES and procalcitonin (PCT) is limited. This case report highlights the fact that PCT levels can be markedly elevated in patients with acute FPIES. An 11-month-old girl previously diagnosed with FPIES underwent an oral food challenge test (OFC). Her serum PCT levels were measured after she developed severe symptoms including fever and shock following administration of 100mL of formula milk. The PCT levels were extremely elevated but improved without antibiotics the next day. The fact that serum PCT levels may be significantly elevated in FPIES means that differentiating severe FPIES from sepsis could be more challenging than was previously thought.