Although invasive aspergillosis is the most common invasive mold disease (IMD), mucormycosis and other non- Aspergillus opportunistic mold infections are increasingly associated with significant morbidity and mortality among highly immunocompromised patients. Early clinical suspicion is critically important to accurately distinguish,…
Aspergillus is a ubiquitous organism with an ecological niche in the soil. Most disease is primarily caused by A. fumigatus , A. flavus , A. niger , A. terreus , and A. nidulans, and classification of the genus has been…
Polyomavirus (PyV) infections were first described in mice in 1952 as a cause of tumors in newborn animals. Since then, PyVs have been found in virtually all vertebrates, including primates, monkeys, cows, rabbits, birds, and fish. BK polyomavirus (BKPyV) was…
Adenoviruses In the past few decades, significant progress has been made in understanding the epidemiology of adenovirus infections and developing preventative and therapeutic strategies. However, adenovirus infections remain a clinical and diagnostic challenge. Isolation of adenovirus does not necessarily correlate…
Epidemiology and risk factors The seasonality of respiratory virus infections among immunocompromised children is similar to that in the community ( Fig. 21.1 ). Respiratory syncytial virus (RSV) typically circulates in the community from November through March, with peak detection…
Over the past several decades, three novel human herpesviruses (HHVs) have been identified and designated HHV-6, HHV-7, and HHV-8. HHV-6 has since been designated as two distinct species, HHV-6A and HHV-6B. HHV-6 was first isolated from the white blood cells…
Herpes simplex virus (HSV) types 1 and 2 (HSV-1 and -2) and varicella-zoster virus (VZV) comprise the human α-herpesviruses, a subfamily of enveloped, double-stranded DNA viruses defined in part by the ability to be transmitted and replicate in mucoepithelial surfaces…
Epstein-Barr virus (EBV) is a human γ-herpesvirus that is associated with important syndromes in both the immunocompetent and immunocompromised host. It is a ubiquitous virus, as it is found worldwide. In community settings, EBV is primarily transmitted by exposure to…
Viral infections represent a significant cause of morbidity and mortality among children who have undergone either solid organ (SOT) or hematopoietic stem cell transplantation (HSCT), as well as in children undergoing therapy for malignancies. Herpesviruses, which possess a unique ability…
Mycobacterium tuberculosis infection Epidemiology, risk factors, and pathogenesis Mycobacterium tuberculosis ( MTB) is among the most successful respiratory pathogens worldwide as the majority of those infected are asymptomatic and will live their lifetime without clinical manifestations. Latent infection is defined…