Epidemiology of Diarrheal Illness in Pediatric Oncology Patients.

BACKGROUND: Diarrhea is common in children with cancer, but this has not been systematically studied to date. METHODS: Remnant stool samples collected between January 2010 and June 2011 from pediatric oncology patients with diarrhea were tested for bacterial, viral, and parasitic enteropathogens using a combination of standard-of-care (SOC) diagnostic tests, including broad-range, real-time polymerase chain reaction (PCR) assays for adenoviruses, astroviruses, and sapoviruses and 2 commercially available multiplexed PCR assays. Corresponding demographic and clinical data were abstracted from patients' medical records. RESULTS: One hundred fourteen episodes of diarrhea in 93 patients (median age, 3.7 years; range, 0.2-18.8) were included in the study. No patients died, but morbidity was significant. A total of 158 potential pathogens were detected in 114 diarrhea episodes, with >1 organism in one third of these; the most common were Clostridium difficile, noroviruses, adenoviruses, and astroviruses. Clostridium difficile, in combination with norovirus or adenovirus, was most common when >1 pathogen was detected. When both studies were obtained, SOC and broadly multiplexed PCR tests were concordant in 64 episodes (56%). Forty-five pathogens (28%) were identified retrospectively by broadly multiplexed PCR assays only. A total of 19 (13%) were detected by SOC real-time PCR assays but not by either commercially available multiplexed PCR assay. CONCLUSIONS: Most pediatric oncology patients in this study had 1 or more potential infectious causes for their diarrhea. Additional studies are warranted to understand the natural history of gastroenteritis in this patient population. Although broadly multiplexed PCR assays offer some advantages over conventional testing, there may be disadvantages to their use for the diagnosis of infectious gastroenteritis that are unique to pediatric oncology patients.

A large multi-pathogen gastroenteritis outbreak caused by drinking contaminated water from antique neighbourhood fountains, Erzurum city, Turkey, December 2012.

We investigated a gastroenteritis outbreak in Erzurum city, Turkey in December 2012 to identify its cause and mode of transmission. We defined a probable case as onset of diarrhoea (⩾3 episodes/day) or vomiting, plus fever or nausea or abdominal pain during 19-27 December, 2012 in an Erzurum city resident. In a case-control study we compared exposures of 95 randomly selected probable cases and 95 neighbourhood-matched controls. We conducted bacterial culture and real-time multiplex PCR for identification of pathogens. During the week before illness onset, 72% of cases and 15% of controls only drank water from antique neighbourhood fountains; conversely, 16% of cases and 65% of controls only drank bottled or tap water (adjusted odds ratio 20, 95% confidence interval 4·6-84, after controlling for age and sex using conditional logistic regression). Of eight stool specimens collected, two were positive for Shigella sonnei, one for astrovirus, one for astrovirus and norovirus, and one for astrovirus and rotavirus. Water samples from the fountains had elevated total coliform (38-300/100 ml) and Escherichia coli (22-198/100 ml) counts. In conclusion, drinking contaminated fountain water caused this multi-pathogen outbreak. Residents should stop drinking water from these fountains, and clean water from the water treatment plant should be connected to the fountains.

Astrovirus encephalitis in boy with X-linked agammaglobulinemia.

Encephalitis is a major cause of death worldwide. Although >100 pathogens have been identified as causative agents, the pathogen is not determined for up to 75% of cases. This diagnostic failure impedes effective treatment and underscores the need for better tools and new approaches for detecting novel pathogens or determining new manifestations of known pathogens. Although astroviruses are commonly associated with gastroenteritis, they have not been associated with central nervous system disease. Using unbiased pyrosequencing, we detected an astrovirus as the causative agent for encephalitis in a 15-year-old boy with agammaglobulinemia; several laboratories had failed to identify the agent. Our findings expand the spectrum of causative agents associated with encephalitis and highlight unbiased molecular technology as a valuable tool for differential diagnosis of unexplained disease.

[Analysis of epidemiologic feature and genetic sequence of Sapovirus in China].

To investigate epidemiologic feature and genetic variance of Sapovirus among children in China, fecal specimens were collected from children under 5 years old with acute diarrhea from Feb 2006 to Jan 2007 in nine provinces including Anhui, Fujian et al. A total of 1,110 fecal samples were detected for Sapovirus by reverse transcriptase-PCR (RT-PCR). Ten samples (0.9%) were positive for Sapovirus. The PCR products were then sequenced and analysed by phylogenetic tree. The results indicated that the detected Sapovirus strains were classified into two genogroups and three genotypes, including G I/1, G I/3, G II/3.

[Diarrhea caused by adenovirus and astrovirus in hospitalized immunodeficient patients]. / Diarrea por adenovirus y astrovirus en pacientes inmunodeficientes hospitalizados.

BACKGROUND: Acute or chronic diarrheal illness are common complications in immunosuppressed patients such as human immunodeficiency virus (HIV)-infected, bone marrow or solid organ transplanted patients and those with leukaemias or other immune deficiency disorders. Due to the importance of recognizing the feasible etiologies of diarrhea in order to give the proper antimicrobial chemotherapy or to avoid a misdiagnosis of rejection in the case of transplanted patients, we have investigated adenovirus and astrovirus antigen in faeces from different immunosuppressed patients. PATIENTS AND METHODS: Stool samples from 258 immunodeficient patients hospitalized at University Hospital Complex of Santiago of Compostela with acute or persistent diarrhea were collected between 1997-99 and assayed for astrovirus and adenovirus antigen. Viral antigen was detected by EIA. Other common enteric pathogens were also assayed. RESULTS: Adenovirus antigen was positive in 5 cases (2%) and astrovirus antigen in 12 cases (5%). The most commonly patients infected was those with haematologic disorders and premature infants. HIV-infected patients were positive for astrovirus antigen in 3 cases. The majority of the cases were related with intestinal bacterial diseases or other circumstances, such as Clostridium difficile infection, both associated with prolonged antimicrobial therapy. CONCLUSIONS: Astrovirus and adenovirus have to be considered as enteropathogens specially in immunocompromised hospitalized patients. An accurate diagnosis about diarrhea etiology is advisable in order to give a specific antimicrobial therapy, when it be necessary, or to avoid a misdiagnosis of rejection, in transplanted patients.