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…
Bartonella Epidemiology and risk factors Bartonella species are fastidious, slow-growing, gram-negative bacilli. There are 45 different species that can cause disease in zoonotic hosts, with Bartonella henselae and Bartonella quintana causing most Bartonella -related disease in human hosts in the…
Common mechanisms of gram-negative resistance Gram-negative organisms are divided into the Enterobacteriaceae (e.g., Escherichia coli, Klebsiella species, Enterobacter cloacae ) and the glucose nonfermenting gram-negative organisms ( Pseudomonas aeruginosa , Acinetobacter baumannii , Stenotrophomonas maltophilia ). Drug resistance in Enterobacteriaceae…
Prevention of infections by direct contact Children are particularly prone to infections acquired by direct contact. Frequently, children engage in behaviors that place them at risk, such as placing their hands in their nose or mouth and then touching surfaces,…
General principles Children with deficient immune mechanisms, immunologic disorders, or those receiving immunosuppressive therapy (e.g., radiation, cytotoxic chemotherapy, antirejection medication, and steroids) are identified as high-risk patients with the greatest risk of acquiring healthcare-associated infections. Patients in this subset include…