The association found between CMV shedding in saliva and CMV viremia in this study opens the possibility of future studies of using viral load in saliva as a predictor of viremia. The implementation of herpesviral load in saliva samples for early clinical intervention in pediatric recipients needs a study with a large number of samples for further conclusions.

INTRODUCTION Acute liver failure is rare in pediatric patients and is one of the most challenging medical emergencies due to its prognostic and therapeutic implications. The best scientifi c evidence worldwide comes from multicenter studies in developed countries. In Cuba, there are no prior studies of this disorder in children.OBJECTIVES Describe the main clinical features of Cuban children treated at a national referral center for acute liver failure, as defi ned by recognized diagnostic criteria for pediatric patients.METHODS A case series study was conducted comprising patients diagnosed with acute liver failure treated from 2005 to 2011 in the hepatology and liver transplant service at Havana's William Soler University Children's Hospital. Variables were age group, etiology of acute liver failure, grade of hepatic encephalopathy, blood chemistry variables, and clinical outcome (whether or not spontaneous recovery of liver function occurred). Associations between variables were assessed using contingency tables, and case fatality was calculated, as well as relative risk with its 95% confi dence interval. The Mann-Whitney U test was used to compare means of laboratory test results. RESULTSMedian age of the 31 patients studied (14 boys and 17 girls) was 24 months (range 1-180). Time between symptom onset and diagnosis of acute liver failure was 25.1 days (SD 16.8). Infection was the most common etiology, present in 61.3% of cases (19/31); nonhepatotropic viruses, especially cytomegalovirus, predominated in infants. Spontaneous recovery occurred in 15 patients (48.4%), 3 (9.7%) received transplants, and 13 died, for a case fatality of 41.9%. Outcome was not associated with etiology (p = 0.106), but was statistically associated with degree of hepatic encephalopathy (p <0.01): 77.8% of patients (7/9) with grades III-IV encephalopathy died, for a relative risk of 4.0 (95% CI 1.15-13.8), versus 11.1% (1/9) with grade II or less encephalopathy. Cholesterol levels were signifi cantly lower in patients who failed to recover spontaneously (p <0.01).CONCLUSIONS Patients' clinical characteristics in this case series were similar to those described in developed countries.The fact that nonhepatotropic viruses (basically, cytomegalovirus in infants) are the main cause of acute liver failure in Cuban children calls for further epidemiologic study and identifi cation of local underlying determinants of this phenomenon.

PurposeIn Cuba, viral monitoring in the post-transplant period was not routinely performed. The aim of this research is to identify the most frequent viruses that affect transplanted Cuban children, by implementing a viral follow-up during the post-transplant period.MethodsThe study population included all Cuban pediatric patients who underwent solid organ transplantation (SOT) between November 2009 and December 2012. A total of 34 transplanted pediatric patients of kidney (n = 11) and liver (n = 23) were prospectively monitored during a 34-week period for viral DNAemia and DNAuria by simultaneous detection of cytomegalovirus (CMV), Epstein-Barr virus, herpes simplex virus type 1 and 2, varicella zoster virus, human herpesvirus 6, human adenovirus, and polyomaviruses (BKV and JCV) using quantitative real-time polymerase chain reaction (qRT-PCR).ResultsViral genome of at least one virus was detected in 21 of 34 recipients, 18 patients excreted virus in urine while 12 presented DNAemia. CMV (41.2%) and BKV (35.3%) were the most frequent viruses detected during the follow-up. CMV was the virus mainly associated with clinical symptoms and DNAemia. Its excretion in urine (with cut off value of 219 copies/mL) was associated with detection in plasma (p < 0.001); furthermore, CMV viruria was predictive of CMV viremia (OR:8.4, CI:2.4-29.1, p = 0.001). There was no association between high viral load and clinical complications, due to the prompt initiation of preemptive ganciclovir. Conclusion: This comprehensive viral monitoring program effectively prevents the development of critical viral disease, thus urge the implementation of qRT-PCR as routine for viral monitoring of transplanted Cuban organ recipients.

We investigated the frequency of BKV, JCV and SV40 reactivation in three groups of Cuban patients by multiplex nested PCR assay of 40 paraffin-embedded colorectal neoplasm tissues, 113 urine samples, and 125 plasma samples from 27 transplant recipients, and cerebrospinal fluid (CSF) from 67 HIV-1-infected individuals with central nervous system (CNS) disorders. None of these polyomaviruses were detected in colorectal neoplasms. JCV DNA was detected in 2 of 67 patients (2.9%) with CNS disorders, but neither BKV nor SV40 was identified. BKV was found in urine from 38.5% and 28.6% of adult and pediatric transplant recipients, respectively. In adult renal transplant recipients, excretion of BKV in urine was significantly associated with episodes of acute rejection (p=0.012) and with excretion of HCMV in urine (p= 0.008). In Cuba, the polyomaviruses studied here could not be related to colorectal neoplasms, and JCV was rarely detected in CSFs of HIV-1-infected individuals, whilst BKV reactivation was found to occur frequently in organ transplant recipients.