difficile infection should be treated with metronidazole with consideration of vancomycin for fulminant disease, relapsing disease or non-responsive infection (category IV recommendation), following the recommendations for treatment in HIV-seronegative

populations outlined in Department of Health guidelines [50]. Therapy PF-562271 purchase is indicated for C. difficile infection regardless of the CD4 cell count. Acute bacterial diarrhoea in HIV-seropositive individuals with CD4 counts >200 cells/μL usually does not require treatment, but should be treated when the CD4 count is <200 cells/μL (category IV recommendation). 4.4.1.4 Impact of HAART. Trimethoprim-sulphamethoxazole (TMP-SMX, co-trimoxazole) reduced the incidence of infectious diarrhoea

in the pre-HAART era [51]. Retrospective studies suggest that introduction of antiretroviral therapy, including zidovudine monotherapy, has been more effective than targeted antimicrobial prophylaxis in preventing recurrence Tanespimycin of nontyphoidal salmonella [52], and that duration of antimicrobial prophylaxis, with agents such as fluoroquinolones need not exceed 30 days in patients established on HAART [53]. The incidence of bacterial diarrhoea declined steadily after the introduction of HAART [28], therefore HAART is the mainstay of preventing bacterial diarrhoea (category III recommendation). 4.4.2.1 Background and epidemiology. Cytomegalovirus (CMV) is a member of the herpes family of viruses, usually acquired during

childhood. CMV infection remains dormant unless an individual becomes immunosuppressed, when reactivation of latent infection may occur [54,55]. In the pre-HAART era, retinitis was the most common presentation of CMV [56], followed by gastrointestinal disease (see Org 27569 Table 4.2 for a list potential clinical manifestations of CMV in the GI tract). Most of the data about incidence of CMV were obtained from populations with retinitis. The majority of affected individuals had CD4 counts <100 cells/μL, with 80% of episodes occurring in those with CD4 counts <50 cells/μL. Since the advent of HAART, CMV infection may occasionally occur as part of immune reconstitution syndromes, but the overall incidence of CMV in individuals living with HIV has dramatically reduced [57]. 4.4.2.2 Presentation. CMV may affect all sections of the gut. Table 4.2 illustrates clinical presentation according to area affected. 4.4.2.3 Diagnosis. CMV viraemia, detected by polymerase chain reaction (PCR), may be positive in the absence of end-organ disease and several studies have shown this to be of negligible diagnostic use [58,59]. As indicated in Table 4.2, endoscopy may reveal classical CMV ulceration of the gut mucosa and biopsy with histopathological review may identify characteristic intranuclear and intracytoplasmic ‘owl’s eye’ inclusions [60]. The absence of ulceration makes a diagnosis of CMV colitis very unlikely [61].