P062 Crohn's disease presenting as fever of unknown origin in a six-year-old male
Authors: Michelle Rosario , Elimarys Perez-Colon 
Published: July 2019

BACKGROUND:
Inflammatory Bowel Diseases (IBD) are rising in incidence in the pediatric population. While most present classically, some have limited findings. We present a case of pediatric Crohn's Disease (CD) diagnosed during a fever of unknown origin (FUO) evaluation. We aim to stress the importance of uncommon presentations of a diagnosis with significant implications and requiring prompt intervention.

CASE:
A 6-year-old male presented with 2 weeks of evening 104–106 F fevers, weakness, decreased intake, and weight loss. He also had one loose, non-mucous, non-bloody stool daily. Fevers failed to resolve with outpatient courses of antibiotics and CRP continued to rise. History revealed camping in North Carolina 2 weeks preceding symptom onset. Family history was unremarkable. No further symptoms, including abdominal pain, were elicited. Exam exhibited fever, tachycardia, tachypnea, uvular and palatal ulcers, dry mucous membranes, cervical, submandibular and inguinal lymphadenopathy. No skin, eye, joint, perianal or abdominal findings observed. Preliminary labs showed hypoalbuminemia (2.6), elevated CRP (7.4) and ESR (55), mild leukocytosis (14.9), and microcytic anemia (Hgb 10.1, MCV 71.8). An extensive FUO evaluation failed to identify a source and thus imaging was pursued. CT abdomen/pelvis showed terminal ileitis and free fluid along the right paracolic gutter and right hepatic margin. Endoscopic evaluation for IBD discovered esophagitis along with ulcerations, edema and friable mucosa in the terminal ileum. Pathology was significant for active chronic lymphoplasmacytic gastritis with eosinophils and subtle early granulomatous inflammation with multinucleated giant cells. Distal esophagus showed chronically active inflammation and lymphocytic esophagitis without granulomas. Terminal ileum biopsy revealed active, chronic granulomatous ileitis with ulceration and granulation. No organisms noted throughout. He was diagnosed with CD and initiated on steroids along with Mesalamine.

DISCUSSION:
One quarter of IBD is diagnosed by the age of 20, with 4% presenting before 5 and 18% before 10 years of age. Recent incidence reports show combined U.S. and Canadian data of 10 per 100,000. Prevalence in the U.S. alone is 100–200 per 100,000. Furthermore, IBD in those less than ten is becoming more common. With recent therapeutic advances, significant morbidity and mortality is preventable. However, treatment delays occur from a diagnostic lag in 20% when symptoms are ambiguous. This case highlights early onset IBD and brings attention to non-classic presentations. Our patient was diagnosed 1.5 months after initial symptoms. An average diagnosis lag time of about 3.4 months in pediatric CD has been documented, with further delay if pre-existing gastrointestinal symptoms exist (26 months). Whereas CD is considered when abdominal pain, diarrhea, and weight loss are identified, our patient presented with daily fever along with oral lesions, lymphadenopathy and weight loss. A few case reports cite FUO, another difficult and often unclear diagnosis, as the presentation for IBD. Fever as the sole initial symptom for IBD occurs in 10-15% of cases. IBD is a complicated illness, especially in the pediatric population. When considering effects on growth, psychosocial development and the long-term complications, we must consider IBD in the differential of pediatric patients with vague and persistent symptoms including FUO.