Case Presentation: A thirteen-year-old boy with history of asthma presented to an urban pediatric Emergency Department in the Ohio River Valley with a two-week history of severe chest and abdominal pain, sore throat and shortness of air. He had brief improvement on prednisone after evaluation by PMD however on cessation of steroids, his symptoms recurred. Admission exam notable for stable hemodynamics without hypoxemia. Cardiovascular exam was significant for a loud friction rub and abdominal exam showed hepatosplenomegaly. CT chest showed a large pericardial effusion without parenchymal lung involvement. Echocardiogram re-demonstrated a large pericardial effusion with right atrial collapse. He was started on ibuprofen and prednisone, with a thorough immunologic, infectious, and neoplastic workup identifying positive antibodies against Histoplasma M antigen. Ibuprofen was continued, prednisone stopped and colchicine started with subsequent pericardiocentesis, leading to resolution of symptoms and effusion.
Discussion: Histoplasmosis is a common, often asymptomatic, endemic mycosis common to the Ohio and Mississippi River Valley. Of the 5-10 % percent of infected persons who become symptomatic, Histoplasma can cause pericarditis and pericardial effusions (PPE). Without systemic disease, treatment is not indicated in immunocompetent hosts. In these cases, the pathology is an immunologic reaction of the pericardium to the organism and typically does not result from direct seeding into the pericardial space. In developed countries, pericarditis is most typically idiopathic or viral, although it can also be a manifestation of systemic infection such as Histoplasmosis, malignancy or rheumatologic processes. In the pediatric population, PPE represents an important cause of chest pain and a significant risk factor for cardiac tamponade. NSAIDs continue to be the initial standard of care with colchicine representing an important adjunct in recurrent cases. As experienced in this case, glucocorticoids often add significant symptomatic benefit, however are also associated with an increased recurrence rate, particularly when high doses are tapered rapidly.
Conclusions: This case highlights an uncommon presentation of Histoplasma disease, in the absence of lung parenchymal disease or respiratory symptoms. A 2011 cases series in Pediatric Emergency Care found idiopathic pericarditis accounted for 68% of pericarditis. Further work-up for systemic causes may not always be performed in immunocompetent individuals. Idiopathic cases could be secondary to Histoplasmosis, particularly in the endemic Midwestern region. A recent multicenter study on PPE in the Journal of the American Heart Association in 2014 found a significant risk of re-admission in patients localized to the Midwest. We propose that Histoplasma may be a causative agent of idiopathic PPE in endemic areas and this represents an opportunity for further study.
