Diarrhea and Enteric Emerging Viruses in HIV-Infected Patients

Abstract

To evaluate the prevalence of enteric viruses and their possible association with diarrhea, 244 stool samples were collected from HIV-infected and uninfected patients with or without diarrhea (subgroups I-a, Ib, II-a, and II-b, respectively). Subjects were screened by polyacrylamide gel electrophoresis, latex agglutination, and enzyme immunoassays for rotaviruses, adenoviruses, picobirnaviruses, and astroviruses. Enteric viruses were found significantly more often in specimens from HIV patients (20%) than in specimens from uninfected HIV patients (0%) (p < 0.05). Picobirnavirus was detected in 14.63% of 82 HIV-infected patients with diarrhea, but it was detected neither in those without diarrhea (0%) (p < 0.05) nor in the groups of uninfected HIV subjects (0%) (p < 0.05). Nor could astrovirus (subgroups I-a [4.00%] versus subgroup I-b [5.26%],p > 0.05) or enteric adenovirus (subgroup I-a [1.22%] versus subgroup I-b [0%], p > 0.05) be linked to the diarrhea disorder in HIV-infected patients. Rotaviruses were not detected in any of the clinical subgroups studied. Enteric viruses were detected in 15 of 93 (16.13%) of the HIV-infected patients with CD4+ T cell count <200/microl and 3 of 19 (15.79%) of those HIV-infected individuals with a CD4+ T cell count 200-499/microl, showing no significant difference (p > 0.05). According to our data, unusual enteric viruses such as picobirnavirus, astrovirus, and enteric adenovirus occur in HIV-infected population in Córdoba, Argentina. However, only picobirnaviruses could be significantly associated with diarrhea in these patients.

Human Astroviruses

“…HAstVs affect predominantly the pediatric population (117,164,229,230), although infections in elderly people and immunocompromised hosts are also reported (231)(232)(233)(234)(235)(236). In addition, astrovirus gastroenteritis may also affect healthy adults (88,89,207).…”

Animal Picobirnavirus

“…The primary objective of these environmental studies was to evaluate PBV as an indicator of fecal contamination, the potential health risk of the presence of PBVs in sewages and natural water resources should not be neglected and this finding deserves further investigations. Studies in immuncompromised and immunosuppressed hosts indicated that these viruses might be 'opportunistic pathogens' [38,39,41,42,44,75,80].…”

“…Thus, the probable role of PBV as either a primary diarrhoeal agent in immunocompetent children [6,7], a potential pathogen in immunocompromised individuals [38,39,44] or an innocuous virus in the intestine remains elusive and needs to be investigated despite the numerous reports of the presence of PBV in fecal samples of various hosts species; our current knowledge of their biology, etiology, pathogenicity or their transmission characteristics remains subtle [15,32,33,57], mainly because of their non-cultivable status (in vivo and in vitro) that is, the absence of a cell culture system and suitable animal model for propagating the virus. Further studies in gnotobiotic animals may shed light on PBV pathogenic potential [15].…”

“…Similarly, PBVs have also been detected as sole pathogens in diarrhoeic animals [9,60,67] and with other known and established enteric pathogens [2,4,83]. They are still classified as 'opportunistic diarrhoeagenic pathogen', since they have been detected from immunocompromised patients and patients with prolonged immunosuppressive treatment who suffered from diarrhoea than non-diarrhoeic controls [18,38,39,41,42,44,75].…”

Molecular Characterization of Porcine Picobirnaviruses and Development of a Specific Reverse Transcription-PCR Assay

“…Despite the numerous reports of the presence of PBV in fecal samples from vertebrates, the pathogenicity of these viruses has not been established. However, studies conducted with human immunodeficiency virus-infected persons (13,15) suggest that PBV may be an opportunistic pathogen that may cause diarrhea in immunosuppressed individuals.…”