Adenovirus Pneumonia – An Under-Recognized Cause of Morbidity in Children
J Pinczewski, RJ Castellani. University of Maryland, Baltimore, MD
Background: Adenovirus (AV), a ubiquitous non-enveloped, icosahedral double-stranded DNA virus is a common cause of human infections. 52-serotypes of AV have been identified, and these cause morbidities ranging from upper respiratory tract infections (RTI) to gastroenteritis. In immunocompromised patients and young children, AV infections are often much more severe and may include lower RTI and meningoencephalitis. We present an autopsy case performed on a 2-yr old girl who was admitted with respiratory compromise, which progressed to bacterial pneumonia, sepsis, and death 8-days after admission.
Design: The autopsy was performed using the Letulle method. Resected tissue was fixed in 10% buffered formalin and embedded in paraffin. Tissue sections (5μm) were cut and then stained with hematoxylin and eosin. Electron Microscopy (EM): Fragments of formalin-fixed lung tissue were cut into 1-mm cubes. These were then fixed in 4F1G for 4 hours, postfixed in osmium tetroxide, dehydrated in graded alcohols, and embedded in epoxy resin. The sections were stained with uranyl acetate and lead citrate and examined on a JEM 1200 transmission EM.
Results: On autopsy, viral cytopathic effects manifesting primarily as smudgy nuclear chromatin were identified within pneumocytes, while EM studies demonstrated hexagonal 90 nm viral particles containing nucleocapsids in Figure 1 and within pulmonary endothelial cells in Figure 2. Both the light microscopic and EM findings were typical of AV, indicating that the decedents respiratory failure, which initiated the cascade of events that lead to her death, was likely due to AV pneumonia.
Conclusions: ADV is an under-recognized cause of severe morbidity and mortality in children and immunocompromised patients. This case emphasizes the difficulty in clinical diagnosis of ADV pneumonia, the need for clinicians to maintain adenovirus infection in the differential diagnosis, and the importance of autopsy examination in general for case characterization.
Wednesday, March 24, 2010 9:30 AM
Poster Session V # 10, Wednesday Morning