Human bocavirus detection and quantification in fecal and serum specimens from recipients of allogeneic hematopoietic stem cell transplantation: A longitudinal study

Abstract

Objectives: The aim of this study was to evaluate the occurrence of human bocavirus (HBoV) and to determine viral loads in samples of patients admitted for allogeneic hematopoietic stem cell transplantation (allo-HSCT).Methods: Fecal and serum samples were collected from 19 patients, during a 24-month period. Samples were screened by quantitative polymerase chain reaction TaqMan assay, with specific probe and primers targeting the NP1 gene of all HBoVs genotypes (HBoV-1 to -4), and viral loads were determined using serial dilutions of a recombinant plasmid.Results: HBoV DNA was detected in 42.1% (8 of 19) of the patients in at least one type of sample (feces and/or serum) during the study period, with 75% (6 of 8) of the patients being positive in both types of sample. Viral shedding in feces had a median of 26 days (range, 5 to 121) and viremia was detected in 87.5% (7 of 8) of the patients. The HBoV loads in fecal samples were higher than in sera and, in most cases, HBoV was detected earlier in fecal than in sera samples. In six HBoV-positive patients (6 of 8) diarrhea was observed concomitantly to viral detection in fecal samples.Conclusions: A high frequency and loads of HBoV in allo-HSCT recipients was observed, especially in fecal samples. Positivity in fecal samples was an early predictor of HBoV presence.

Human Bocavirus in Brazil: Molecular Epidemiology, Viral Load and Co-Infections

“…Other studies performed in Brazil have accessed HBoV DNA in stool samples from patients with underlying medical conditions, such as HIV infected and immunosuppressed transplanted patients, showing detection rates varying from 13% to 21.4% [ 33 , 34 , 35 ]. Worldwide, several studies have detected HBoV in hospitalized children and outpatients with AGE at rates between 3.5% and 19.3%, in countries such as China, Spain, Chile, Pakistan and South Africa [ 14 , 36 , 37 , 38 , 39 , 40 ].…”

Respiratory Viral Pathogens in Solid Organ and Hematopoietic Stem Cell Transplant Recipients

“…These same data suggest that BoV patients with active symptoms are more likely to have a co-pathogen when detected [214]. Increased detection among HSCT recipients in stool may be evidence that the GI tract is the more common location for this pathogen [215]. Novel enterovirus (EV), such as EV-D68, are infrequent but are known to lead to clinical illness among transplant patients that varies between mild URI to severe respiratory disease [216].…”

Viral Enteritis in Solid-Organ Transplantation

“…HBoVs can cause respiratory infections and gastroenteritis in immunocompromised patients [51]. There are four HboV genotypes, of which genotypes 2-4 have been considered enteric pathogens [52,53]. The rate of HboV coinfections with other respiratory and gastrointestinal pathogens seems to be high, raising the question if HboV is a true pathogen or innocent bystander [52,53].…”

“…There are four HboV genotypes, of which genotypes 2-4 have been considered enteric pathogens [52,53]. The rate of HboV coinfections with other respiratory and gastrointestinal pathogens seems to be high, raising the question if HboV is a true pathogen or innocent bystander [52,53]. Recent data support that HboV, during its natural infection, can establish latency in host cells.…”

“…However, the mechanisms of persistence, latency, and reactivation of HboV are not well understood [53]. In a recent study examining allogeneic HSCT recipients, HBoV was detected in both serum and fecal specimens, supporting its role as an enteric pathogen [52]. Most of the HBoV infections are asymptomatic, but in symptomatic patients, nausea, diarrhea, abdominal pain, and respiratory symptoms are common [51,54].…”