Multisystem Involvement in a Pediatric Patient with Peripheral Eosinophilia
Abstract
Introduction:
Peripheral eosinophilia, defined as an absolute eosinophil count (AEC) ≥500/μL, can be connected to many disease states that range in prevalence and severity. Often it is a sign of singular organ involvement, such as asthma or eczema. Rarely, it can be an indicator of a more infiltrative process requiring timely diagnosis and treatment. One rare pediatric diagnosis associated with eosinophilia is hypereosinophilic syndrome (HES). HES is an umbrella term for a group of rare disorders defined by persistent AEC of ≥1500/μL, as well as hypereosinophilia (HE) associated multiorgan manifestations. Data on HE in pediatric patients is limited. This is a case of a pediatric patient who developed progressive pulmonary, gastrointestinal (GI), and hematologic disease from HES.
Case Presentation:
Our patient is a previously healthy 13-year-old African American male with a recent diagnosis of severe persistent asthma, bronchiectasis, and gastritis. He initially presented seven months prior due to new symptoms of wheezing and respiratory distress which required β-agonist and steroid treatment. His pathology was determined to be viral-induced wheeze, but he was diagnosed with asthma during pulmonology follow-up several weeks later. Two months later, the patient required admission for hemoptysis and was found to have bronchiectasis of unknown origin. He was sent home on antibiotics and a steroid taper. He then presented four months later with complaints of abdominal pain, vomiting, diarrhea, and labs significant for HE (AEC of 20,088/μL) which led to further testing. Bone marrow biopsy and bronchoscopy were performed, with no diagnostically significant results. Rheumatology was consulted, but as his antineutrophil cytoplasmic antibody was previously negative and he did not have multi-organ dysfunction, further workup was deferred.
He continued to have diarrhea and significant abdominal pain following discharge. Due to this, an endoscopy was performed, revealing scattered intraepithelial eosinophils in the duodenum, esophagus, and throughout the colon. His HE persisted, with an AEC of 10,876/μL at the time of the scope. He was readmitted and received an infectious disease workup for parasitic etiology that returned negative.
During his admission, computed tomography angiography of the abdomen/pelvis was obtained to evaluate for intestinal vasculitis and eosinophilic disease. It showed no vascular abnormality but revealed wall thickening and enhancement of the ileum concerning for eosinophilic enteritis. Cardiac imaging results were normal.
A diagnosis of HES was concluded from his new onset asthma, bronchiectasis/chest imaging abnormalities, GI symptoms and biopsy results, and peripheral HE. Despite being on high-dose oral prednisone for over six months, it was thought that the patient was having poor absorption due to extensive GI inflammation. He was transitioned to intravenous steroids which resulted in normalization of his AEC. Nucala therapy was initiated while inpatient and he was discharged on an oral steroid taper.
Discussion:
HES is defined by presence of peripheral blood HE and multi-organ dysfunction directly caused by tissue eosinophilia. Eosinophils infiltrate the body, causing inflammatory changes and ultimately organ dysfunction. Our patient was a previously healthy male who developed asthma, bronchiectasis, and gut involvement in addition to peripheral eosinophilia. The incidence and prevalence of HES is not well defined in adults or pediatrics, due to variation in clinical presentation, underreporting, and underdiagnosis. The prevalence of pediatric HE is reported as 31.4/100,000, and the incidence rate of HES, age adjusted, is approximately 0.4/million.
While he meet clinical criteria for eosinophilic granulomatosis with polyangiitis, another disease associated with eosinophilia that can present with similar clinical findings as HES, no lung biopsy was obtained to be able to make such a diagnosis. Steroids are the first-line treatment for HES, but pediatric cases of HES are often severe, and steroids are often not sufficient to induce remission. Immunomodulatory agents, like Nucala, that block signaling of eosinophil production are often required to treat, as in this case.
Conclusion:
We present a rare pediatric case of non-infectious multi-system organ damage from HES. This case is an important example of how to recognize, formulate a differential, and manage pediatric HE.