Astrovirus Replication Is Inhibited by Nitazoxanide In Vitro and In Vivo.

Astroviruses (AstV) are a leading cause of diarrhea, especially in the very young, the elderly, and immunocompromised populations. Despite their significant impact on public health, no drug therapies for astrovirus have been identified. In this study, we fill this gap in knowledge and demonstrate that the FDA-approved broad-spectrum anti-infective drug nitazoxanide (NTZ) blocks astrovirus replication in vitro with a 50% effective concentration (EC50) of approximately 1.47 µM. It can be administered up to 8 h postinfection and is effective against multiple human astrovirus serotypes, including clinical isolates. Most importantly, NTZ reduces viral shedding in vivo, exhibiting its potential as a future clinical therapeutic.IMPORTANCE Human astroviruses (HAstV) are thought to cause between 2 and 9% of acute, nonbacterial diarrhea cases in children worldwide. HAstV infection can be especially problematic in immunocompromised people and infants, where the virus has been associated with necrotizing enterocolitis and severe and persistent diarrhea, as well as rare instances of systemic and fatal disease. And yet, no antivirals have been identified to treat astrovirus infection. Our study provides the first evidence that nitazoxanide may be an effective therapeutic strategy against astrovirus disease.

Coronaviruses in cattle.

Bovine coronaviruses are spread all over the world. They cause two types of clinical manifestations in cattle either an enteric, calf diarrhoea and winter dysentery in adult cattle, or respiratory in all age groups of cattle. The role of coronaviruses in respiratory infections is still a hot topic of discussion since they have been isolated from sick as well as healthy animals and replication of disease is rarely successful. Bovine coronavirus infection is characterised by high morbidity but low mortality. The laboratory diagnosis is typically based on serological or molecular methods. There is no registered drug for the treatment of virus infections in cattle and we are limited to supportive therapy and preventative measures. The prevention of infection is based on vaccination, biosecurity, management and hygiene. This paper will cover epidemiology, taxonomy, pathogenesis, clinical signs, diagnosis, therapy, economic impact and prevention of coronavirus infections in cattle.

Detection of Cytomegalovirus in Intestinal Tissue of Infants with Necrotizing Enterocolitis or Spontaneous Intestinal Perforation.

OBJECTIVE: To determine the frequency of detection of cytomegalovirus (CMV) in surgical or autopsy intestinal tissue from infants with necrotizing enterocolitis (NEC) or spontaneous intestinal perforation (SIP) of the small bowel. STUDY DESIGN: This was a retrospective cohort study of infants in the neonatal intensive care unit at Nationwide Children's Hospital, Columbus, Ohio, with NEC (Bell stage ≥2B) or SIP from 2000 to 2016. Paraffin-embedded surgical or autopsy intestinal tissues were examined for CMV by polymerase chain reaction (PCR) and immunohistochemistry (IHC), and clinical characteristics of CMV-positive vs CMV-negative cases were compared. RESULTS: CMV was detected by PCR or IHC in 7 (4%) of 178 infants with surgical or autopsy- confirmed NEC (n = 6) or SIP (n = 1). Among 143 NEC cases (123 surgical, 20 autopsy), CMV was detected in 6 (4%): 4 (2 surgical, 2 autopsy) by both PCR and IHC, and 2 (surgical) by PCR only. Among 35 SIP cases (32 surgical, 3 autopsy), 1 (3%) surgical case was positive, by PCR only. CMV-associated NEC cases had lower median gestational age (24 vs 28 weeks; P = .02), birth weight (649 vs 1121 g; P = .04), and platelet count (16 000/mm3 vs 50 000/mm3; P = .018) compared with CMV-negative cases, respectively. No association was found with receipt of maternal milk, age at NEC diagnosis, male sex, cholestasis, or mortality. CONCLUSIONS: CMV was detected in intestinal tissue from 4% of NEC or SIP cases (NEC, 4%; SIP, 3%). Lower gestational age, lower birth weight, and thrombocytopenia were significantly associated with detection of CMV in NEC or SIP cases.

Cytomegalovirus and other common enteric viruses are not commonly associated with NEC.

AIM: Changes in gut microbiota may contribute to NEC, but most studies focus on bacteria. Case reports suggest a link between cytomegalovirus (CMV) or other enteric viruses and NEC, but there are few case series systematically looking at common potential viral causes. We aimed to assess the presence of candidate viruses in blood or stool of a case series of infants with NEC managed in one surgical centre. METHODS: We identified 22 infants diagnosed with NEC (from November 2011 to March 2014): 17 had suitable blood stored, of whom 14 also had suitable stool samples stored. Blood was analysed with polymerase chain reaction (PCR) for CMV, Epstein-Barr virus (EBV) and adenovirus, and stool by PCR for norovirus, sappovirus, astrovirus, adenovirus and rotavirus. RESULTS: All samples were negative. CONCLUSION: Although case reports indicate an episodic association of enteric viruses in NEC, the inability to detect any of these viruses in our 17 NEC infants suggests that a viral aetiology is unlikely to be causative for most sporadic forms of NEC.

Colonic stenosis post-necrotizing enterocolitis in term newborn with acquired cytomegalovirus infection.

Necrotizing enterocolitis is a gastrointestinal emergency typical of premature infants. Intestinal strictures infrequently complicate medical or surgical treatment of necrotizing enterocolitis. Postnatal cytomegalovirus infection with gastrointestinal linvolvement has occasionally been described in subjects with necrotizing enterocolitis. We report the case of a full term infant presenting necrotizing enterocolitis, acquired cytomegalovirus infection and post necrotizing enterocolitis colonic stricture.List of abbreviations: necrotizing enterocolitis = NEC,cytomegalovirus = CMV.

Microbiota regulates neonatal disease tolerance to virus-evoked necrotizing enterocolitis by shaping the STAT1-NLRC5 axis in the intestinal epithelium.

Microbiota and feeding modes influence the susceptibility of premature newborns to necrotizing enterocolitis (NEC) through mechanisms that remain unknown. Here, we show that microbiota colonization facilitated by breastmilk feeding promotes NOD-like receptor family CARD domain containing 5 (Nlrc5) gene expression in mouse intestinal epithelial cells (IECs). Notably, inducible knockout of the Nlrc5 gene in IECs predisposes neonatal mice to NEC-like injury in the small intestine upon viral inflammation in an NK1.1+ cell-dependent manner. By contrast, formula feeding enhances neonatal gut colonization with environment-derived tilivalline-producing Klebsiella spp. Remarkably, tilivalline disrupts microbiota-activated STAT1 signaling that controls Nlrc5 gene expression in IECs through a PPAR-γ-mediated mechanism. Consequently, this dysregulation hinders the resistance of neonatal intestinal epithelium to self-NK1.1+ cell cytotoxicity upon virus infection/colonization, promoting NEC development. Together, we discover the underappreciated role of intestinal microbiota colonization in shaping a disease tolerance program to viral inflammation and elucidate the mechanisms impacting NEC development in neonates.

Association of Adverse Hearing, Growth, and Discharge Age Outcomes With Postnatal Cytomegalovirus Infection in Infants With Very Low Birth Weight.

Importance: Studies suggest that postnatal cytomegalovirus (CMV) infection can lead to long-term morbidity in infants with very low birth weight (VLBW; <1500 g), including bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC), and neurodevelopmental impairment. However, to date, the association of postnatal CMV with hearing, growth, and length of stay among VLBW infants is unknown. Objectives: To determine the risk for failed hearing screen, increased postnatal age at discharge, or decreased growth at discharge in VLBW infants with postnatal CMV infection compared with CMV-uninfected infants and to compare the risk for other major outcomes of prematurity, including BPD and NEC, in infants with and without postnatal CMV infection. Participants: This multicenter retrospective cohort study included VLBW infants from 302 neonatal intensive care units managed by the Pediatrix Medical Group from January 1, 2002, through December 31, 2016. Infants hospitalized on postnatal day 21 with a diagnosis of postnatal CMV and hearing screen results after a postmenstrual age of 34 weeks were included in the study population. Data were analyzed from December 11, 2017, to June 14, 2019. Main Outcomes and Measures: Infants with and without postnatal CMV infection were matched using propensity scores. Poisson and linear regression were used to examine the association between postnatal CMV and the risk of failed hearing screen, postnatal age at discharge, growth, BPD, and NEC. Results: A total of 304 infants with postnatal CMV were identified, and 273 of these infants (89.8%; 155 boys [56.8%]) were matched with 273 infants without postnatal CMV (148 boys [54.2%]). Hearing screen failure occurred in 45 of 273 infants (16.5%) with postnatal CMV compared with 25 of 273 infants (9.2%) without postnatal CMV (risk ratio [RR], 1.80; 95% CI, 1.14 to 2.85; P = .01). Postnatal CMV was also associated with an increased postnatal age at discharge of 11.89 days (95% CI, 6.72 to 17.06 days; P < .001) and lower weight-for-age z score (-0.23; 95% CI, -0.39 to -0.07; P = .005). Analysis confirmed an increased risk of BPD (RR, 1.30; 95% CI, 1.17 to 1.44; P < .001), previously reported on infants from this cohort from 1997 to 2012, but not an increased risk of NEC after postnatal day 21 (RR, 2.00; 95% CI, 0.18 to 22.06; P = .57). Conclusions and Relevance: These data suggest that postnatal CMV infection is associated with lasting sequelae in the hearing and growth status of VLBW infants and with prolonged hospitalization. Prospective studies are needed to determine the full effects of postnatal CMV infection and whether antiviral treatment reduces the associated morbidity.

Parechovirus infection as a cause of necrotising enterocolitis in a premature neonate.

Parechovirus is becoming increasingly recognised as a cause of morbidity in the neonatal population. It is widely known to cause sepsis, encephalitis and myocarditis. We report a case of parechovirus as a possible cause of necrotising enterocolitis in a premature neonate. The infant, who was born at 28 weeks' gestation, deteriorated at 1 month of life with fever and abdominal distension and had evidence of intramural bowel gas on imaging. Parechovirus was subsequently isolated from naso-oropharyngeal and rectal swabs, and he was managed medically with antibiotics and cessation of enteral feeds.

The Role of Human Coronavirus Infection in Pediatric Acute Gastroenteritis.

Since human coronavirus (HCoV)-like particles were detected in the stool specimens of acute gastroenteritis and necrotizing enterocolitis children with electron microscopy, the relationship between HCoV and the pediatric gastrointestinal illness had been recognized. In recent years, the overall detection rates have been low and have varied by region. HCoVs have not been considered as the major pathogens in pediatric acute gastroenteritis. HCoVs detected in children with acute gastroenteritis have included 229E, OC43, HKU1, NL63, and severe acute respiratory syndrome coronavirus, Middle East Respiratory Syndrome Coronavirus and severe acute respiratory syndrome coronavirus-2 have also been associated with gastrointestinal symptoms in children. Although digestive tract has been recognized as an infection route, it has not been possible to fully investigate the association between HCoVs infection and the gastrointestinal symptoms because of the limited number of pediatric cases. Furthermore, pathologic features have not been clear. Till now, our knowledge of severe acute respiratory syndrome coronavirus-2 is limited. However, diarrhea and vomiting have been seen in pediatric cases, particularly in newborns and infants. It has been necessary to pay more attention on gastrointestinal transmission to identify the infected children early and avoid the children without apparent or mild symptoms becoming the sources of infection.

Outbreak of necrotizing enterocolitis caused by norovirus in a neonatal intensive care unit.

OBJECTIVES: To investigate an outbreak of necrotizing enterocolitis (NEC) in a neonatal intensive care unit (NICU) and to identify the etiology, describe illness risk factors, and develop control measures. STUDY DESIGN: A retrospective case-control study was performed including newborns with NEC and newborns without NEC, examining demographic factors and exposures to medications, staff members, and procedures before illness. Stool samples from affected newborns were collected and tested for bacteria, parasites, and viruses. RESULTS: We confirmed a NEC outbreak in the NICU in January 1998 with 8 cases, including 2 deaths, clustered in time and space. Norovirus-like particles were identified in all available stools from cases; norovirus (NoV) was confirmed with reverse transcriptase polymerase chain reaction in 4 of 6 samples. NEC cases were younger, had lower Apgar scores, and received antibiotics longer than 25 control subjects. Three NICU health care personnel had more contact with cases than control subjects; 1 staff member recalled having gastroenteritis symptoms around the time of the outbreak. CONCLUSIONS: This report associates NoV with NEC. NoV appeared to precipitate NEC in predisposed infants. Spatial clustering and epidemiologic links between cases and a health care worker with gastroenteritis suggests that NoV should be investigated among the etiologies of NEC outbreaks and that interventions targeted to interruption of NoV transmission should be considered.

Detection of astrovirus in premature infants with necrotizing enterocolitis.

BACKGROUND: Necrotizing enterocolitis (NEC) is a major cause of mortality and morbidity in very low birth weight infants (<1500 g birth weight). Although the etiology remains unknown, infectious agents could play a key role. The aim of this analysis was to examine the role of human astrovirus (HAstV) in infants with NEC. PATIENTS AND METHODS: All patients admitted during a 5-year period at a tertiary neonatal intensive care unit with NEC (Bell stage I-III) who had examination of stool specimens for bacterial and for viral infections were included. Clinical data were reviewed and compared between infants with NEC and astrovirus detection (NEC + HAstV) and infants with NEC without astrovirus detection (NEC - HAstV) in stool specimens. RESULTS: Forty infants with NEC were identified between 2002 and 2006 and 8 patients were excluded from statistical evaluation because of incomplete viral examinations. HAstV was detected in stool specimens of 6 (19%) of the remaining 32 patients with NEC. Double infection with rotavirus was identified in 1 patient. No other viruses were detected. Significant differences in patients with NEC - HAstV and NEC + HAstV were only shown for age at onset of illness (P < 0.001) but not for severity of illness, need for surgical intervention, or mortality. CONCLUSIONS: This study demonstrates that HAstV may be associated with the development of NEC in a subgroup of patients and provides further evidence for the important role of gastrointestinal viral infections in this most common gastrointestinal emergency in premature infants. HAstV should be included in microbiological examination of stool specimens in patients with NEC.

Late presentation of necrotizing enterocolitis associated with rotavirus infection in a term infant with hyperinsulinism on octreotide therapy: A case report.

RATIONALE: Congenital hyperinsulinism (CHI) is the most common cause of persistent hypoglycemia in infancy that can cause permanent brain damage. Consequently, optimal management is extremely important. Current pharmacologic and surgical treatment were available that included diazoxide and octreotides. PATIENT CONCERNS: A 4 month old Saudi male patient diagnosed at our hospital as CHI, treated with near total pancreatectomy and octreotide therapy of 30 mcg/kg/day presented with severe abdominal distension, vomiting and bloody diarrhea. DIAGNOSES: The patient was diagnosed as necrotising enterocolitis (NEC) associated with Rota virus infection which played together with octeriotides as risk factors for NEC. INTERVENTIONS: Radiological investigations and multidisciplinary team management with endocrinologist, neonatologist, pediatric surgeon, and gastroenterologist. OUTCOMES: Resolution of NEC with conservative medical management and was discharged after 1 month of hospital stay with follow up with all concerned sub specialties. LESSONS: NEC can develop in patients treated with octreotides especially when associated with another risk factor such as rotavirus infection.

High prevalence of cytomegalovirus infection in surgical intestinal specimens from infants with necrotizing enterocolitis and spontaneous intestinal perforation: A retrospective observational study.

BACKGROUND: Necrotizing enterocolitis (NEC) is a severe, often fatal gastrointestinal emergency that predominantly affects preterm infants, and there is evidence that neonatal cytomegalovirus (CMV) infection may in some cases contribute to its pathogenesis. OBJECTIVES: This study aimed to evaluate the prevalence of CMV in infants with NEC. STUDY DESIGN: Seventy intestinal specimens from 61 infants with NEC, spontaneous intestinal perforation (SIP), or related surgical complications were collected at Karolinska University Hospital and Uppsala University Hospital, Sweden. Ten specimens from autopsied infants without bowel disease served as controls. Samples were analyzed for CMV immediate-early antigen (IEA), CMV late antigen (LA), 5-lipoxigenase (5LO) and CMV-DNA by immunohistochemistry (IHC) and in situ hybridization (ISH), respectively. In 10 index samples, CMV DNA was analyzed with Taqman PCR after laser capture microdissection (LCM) of cells positive for CMV IEA by IHC. RESULTS: CMV IEA was detected by IHC in 57 (81%) and CMV LA in 45 (64%) of 70 intestinal specimens from index cases; 2 (20%) of 10 control specimens were positive for both antigens. 5LO was detected in intestinal tissue section obtained from all examined index and controls. CMV DNA was detected in 4 of 10 samples (40%) after LCM. By ISH, all 13 IHC-IEA-positive samples were positive for CMV DNA; however, 3 of 5 IHC-IEA-negative samples (60%) were also positive. CONCLUSIONS: CMV-specific antigens and CMV DNA were highly prevalent in intestinal specimens from infants with NEC, SIP, and related surgical complications. Our findings provide further evidence that neonatal CMV infection contributes to the pathogenesis of these diseases and may affect patient outcome.

Increased incidence of necrotizing enterocolitis in premature infants born to HIV-positive mothers.

OBJECTIVE: To examine if being born to an HIV-positive mother may increase the risk of necrotizing enterocolitis in premature infants. DESIGN: Case-control study. SETTING: Neonatal unit of a level 3 perinatal centre. METHODS: : Over a period of 8.5 years, all cases of necrotizing enterocolitis occurring in premature infants admitted to the neonatal unit were identified. For each case, two controls were retrospectively chosen that matched for postmenstrual age at birth, intrauterine growth and year of birth. Perinatal characteristics were studied in all infants. MAIN RESULTS: There were 79 cases of necrotizing enterocolitis, which were compared with 158 controls. Using multivariate analysis, multiple pregnancy [odds ratio (OR), 2.29; 95% confidence interval (CI), 1.23-4.25; P = 0.009], abnormal umbilical artery velocity (OR, 2.21; 95% CI, 1.08-4.54; P = 0.030), abnormal fetal heart rate (OR, 2.14; 95% CI, 1.05-4.36; P = 0.036) and HIV-positive mother (OR, 6.63; 95% CI, 1.26-34.8; P = 0.025) were significantly more frequent in fetuses who subsequently developed necrotizing enterocolitis. CONCLUSIONS: This preliminary report suggests an association, not previously reported, between maternal HIV-positive status and an increased risk of necrotizing enterocolitis in premature infants. Despite the limitations of this study, we suggest that premature newborn infants of HIV-positive mothers should be monitored very carefully for a possible increased risk of necrotizing enterocolitis.

Cytomegalovirus-associated necrotizing enterocolitis in a preterm twin after breastfeeding.

Cytomegalovirus (CMV) in breast milk is transmitted to infants and may be associated with disease especially in preterm infants. We present a preterm twin with postnatally acquired CMV infection and evidence of CMV-associated necrotizing enterocolitis.

Asymptomatic DNAemia heralds CMV-associated NEC: case report, review, and rationale for preemption.

Human cytomegalovirus (CMV) infection may be acquired in very low birth weight and extremely low birth weight (ELBW) infants from breast milk. The clinical relevance of such infections is uncertain. There is no consensus on whether screening breast milk for CMV, freezing/pasteurizing milk before feeding, or performing virological monitoring on at-risk infants is warranted. We describe an ELBW infant who acquired CMV postnatally from breast milk and developed CMV sepsis syndrome and clinical evidence of necrotizing enterocolitis (NEC) at ≈ 5 weeks of age. The availability of serial dried blood spots from day of life (DOL) 4 to 21, coincidentally obtained for a metabolic study, provided the novel opportunity to retrospectively test for and quantify the magnitude of CMV DNAemia. DNAemia was present for several weeks before the onset of severe CMV disease, first being noted on DOL 18 and increasing in magnitude daily to 4.8 log10 genomes/mL on DOL 21, approximately 8 days before the onset of abdominal distension and 15 days before the onset of CMV sepsis syndrome and NEC. After surgical resection, supportive care, and ganciclovir therapy, the infant recovered. This case underscores the importance of including CMV infection in the differential diagnosis of sepsis and NEC in premature infants. This case also suggests the value of prospective virological monitoring in at-risk low birth weight and ELBW infants. Future studies should examine the potential utility of preemptive monitoring for, and possibly treatment of, CMV DNAemia in premature infants, which may herald the onset of serious disease.

Clinical neonatal rotavirus infection: association with necrotising enterocolitis.

BACKGROUND: Rotavirus is the most important aetiological agent causing severe gastroenteritis in children <2 years of age in South Africa and worldwide. Most endemic neonatal nursery strains are thought to be asymptomatic. However, serious conditions have been reported to be associated with rotavirus infection, such as necrotising enterocolitis (NEC), diffuse intravascular coagulopathy, pneumonia, apnoea and seizures. METHODS: We studied newborns needing screening for sepsis in our Neonatal Unit. Rotavirus screening was included in the septic screen. The clinical signs and symptoms were studied in the control group (no rotavirus identified) and the study group (rotavirus identified in the stools). RESULTS: Of the 169 babies screened for sepsis, 44 (26%) were rotavirus positive. Of the remainder, 63 comprised the control group. Rotavirus-positive stools were identified from day 4 of life. The virus was excreted in the stools for a mean of 4 days per infection episode. Asymptomatic infection was only observed in one baby; the others had clinical signs and symptoms ranging from mild to severe and even death. Gastrointestinal symptoms were prominent manifestations of rotavirus infection. There was a high incidence of NEC (66% in the study group v. 30% in the control group). Of the rotavirus-infected babies, 9 died; 3 had no other pathogens identified, so that rotavirus infection could have been the cause of death. CONCLUSIONS: Rotavirus infection in the neonate is rarely asymptomatic. It is a dangerous condition that may cause death. It is associated with, and probably a cause of, NEC.

Necrotizing enterocolitis in HIV-exposed and nonexposed infants: clinical presentation and histopathological features.

Necrotizing enterocolitis (NEC) is the most common gastrointestinal emergency in neonates and is associated with significant morbidity and mortality. An association between HIV-positive maternal status and increased risk of NEC in preterm infants has been described, and antiretroviral therapy has been proposed as an independent risk factor. Our aim was to compare the clinical presentation and histopathological features of necrotizing enterocolitis in HIV-exposed and unexposed infants. A retrospective study of archival material from the National Health Laboratory Services Histopathology Laboratory in Tygerberg Hospital/Stellenbosch University from 1992 to 2008 was conducted. All surgical specimens from infants who presented to pediatric surgery for a laparotomy and bowel resection for NEC and in whom the HIV status was known were included in the study. In the 37 cases that fulfilled these criteria, male gender was overrepresented in the study population (67%). Nonsteroidal anti-inflammatory drugs appeared to play a significant role in the development of surgical NEC in infants who were not exposed to HIV, but HIV-exposed infants had a significantly poorer survival rate. There was no significant difference in the histopathology between HIV-exposed and nonexposed infants, and Cytomegalovirus infection was not identified in any of the cases studied.

Cytomegalovirus enterocolitis presenting as abdominal compartment syndrome in a premature neonate.

BACKGROUND: Cytomegalovirus (CMV) enterocolitis is an uncommon intestinal disorder of newborns that is often initially misdiagnosed as necrotizing enterocolitis. METHODS: We treated a premature twin boy with CMV enterocolitis who presented with abdominal compartment syndrome requiring urgent decompression. All patients with neonatal CMV enterocolitis reported were reviewed. RESULTS: Nine previously reported patients with neonatal CMV enterocolitis presented with abdominal distention and signs of sepsis. At the time of surgery, either perforation or stricture was identified. The current report is the first to present with clinical signs of abdominal compartment syndrome. CONCLUSION: CMV is a rare cause of neonatal enterocolitis. Surgical intervention is required for bowel perforation, stricture, or abdominal compartment syndrome.