Introduction

HIV-infected children are at risk for the same minor and serious bacterial infections that affect immunocompetent children, although they occur more frequently and may be more severe in HIV-infected children. Because of this increased risk, the US Centers for Disease Control and Prevention (CDC) added a new category of invasive bacterial infections to the list of pediatric AIDS-defining illnesses in 1987 [1].

Bacterial infections in HIV-infected children often present in a manner similar to HIV-uninfected children and respond to the same antibiotics, although disseminated infection or frequent recurrences are often seen in HIV-infected children. The differential diagnosis may be large because some of these infections can present in a manner similar to opportunistic and endemic infections, including those due to viruses, unusual bacteria, fungi, and parasites. In addition, bacteria that are unusual in the immunocompetent host may cause significant disease in immunosuppressed HIV-infected children (Tables 37.1 and 37.2).

Multiple immunologic abnormalities in HIV-infected children prevent these children from mounting a robust immune response to a broad range of bacterial pathogens (See Chapter 3). These abnormalities include defects in the cell-mediated (T cell) and the humoral (B cell) arms of the immune system, decreases in neutrophil number, multiple defects in neutrophil function, impairment in macrophage and monocyte function [2], functional asplenia [3] and defects in three components of complement [3] (Table 37.1).