The Epidemioligical Studies Of HCMV And BKV Infections In Various Group Of Patients With Different Clinical Manifestations

Human Cytomegalovirus (HCMV) and BK Virus(BKV) have a wide spread in normal individuals, which usually causes inapparent infection with no clinical symptom. In immunosuppression as renal transplants, either of the virus could reactive and lead to graft loss, and even death. HCMV infection is the leading cause of congenital infection, while there was rare data for BKV. In view of this situation, we detect the two viruses in potentially high risk of infection group. Aim to comprehend the distribution of the two viruses in this area, and to study the correlation of the two viruses.Part one:Analysis of 5 differnt methods for extracting BK virus DNA from urine samples.Objective:BK virus is a new pathogen of causing renal damage in renal transplants. There are various methods to detect BK virus, but the sensibility and specificity varies.5 different DNA extracting methods was applied before polymerase chain reaction (PCR), which detect BK virus DNA in urine, considering it's sensitiveness and rapidity. To find a most suitable one for clinical laboratory usage.Methods:5 DNA extracting methods were used to deal with 40 BK virus positive urine samples:high speed centrifugation, SDS boiling lysis, NaOH boiling lysis, PEG precipitation, Tris saturated phenol.Results:The positive rates of the 5 methods above are 78% (31/40),100% (40/40),83% (33/40),95% (38/40),100%(40/40)。Conclusions:Tris saturated phenol is still the best method of extracting BK virus DNA in urine, while SDS boiling lysis is the best substitution cause it's high sensitivity and security.Part two:The epidemiological studies of HCMV and BKV infections in various group of patients with different clinical manifestationsBackground:HCMV infection is common in neonates and renal transplants, while BK Virus Allograft Nephropathy (BKVAN) has been a focus in transplant recipients in recent years. The epidemiological data of BK virus is limited in the word, especially in China, and the transmission mode of BK virus is not clear yet. Both of the viruses could stay in kidney asystemly in a latet state. When virus was reactivated, it could be excreated in urine.Objectives:The major objective is to study the prevalence of human cytomegalovirus and BK virus infection and possible mode of viral transmission. Focus on possible mother/newborn transmission, and transmission via kidney donor or reactivation of human cytomegalovirus and BK virus in transplant patients. Find out the relationship of the two viruses.Methods:To detect human cytomegalovirus and BK virus DNA in morning urine samples from the following groups:pregnant women(606),sick infants(298),hospitalized nephropathy patients(370),renal transplants(107) and healthy individuals(180) by quantitative polymerase chain reaction (Q-PCR). Sick infants and hospitalized nephropathy patients were also divided into groups by diagnoses or manifestation.Results:The positive rates of human cytomegalovirus DNA in the urine of pregnant women,sick neonates,hospitalized nephropathy patients,renal transplant recipients and healthy individuals were 6.44% (39/606),3.36% (10/298),12.97% (48/370),26.17% (28/107),0.56%(1/180), and human cytomegalovirus DNA was identified in all kinds of nephropathy patients with positive rates of about 10%, especially in lupus nephropathy patients with a positive rates of 27.27%. The positive rates of BK virus in these groups were 6.93% (42/606),0.67%(2/298),2.43% (9/370),12.15% (13/107),2.22% (4/180). In addition, the positive rates of BK virus was apparently high in IgA-nephropathy patients and lupus nephropathy patients. In our study, the infection of the two viruses have no correlation.Conclusions:Human cytomegalovirus and BK virus infection rates were both high in pregnant women and renal transplant patients, while Human cytomegalovirus infection is common in sick infants and nephropathy patients. Nephropathy patients may infected by Human cytomegalovirus at the beginning of illness, which could be a risk factor of renal failure. BK virus reactivation is closely related to immunosuppression, with little pathogenicity except for transplant patients. There was no significant evidence for Bk virus's mother-infant transmission in our study for 289 sick infants. There are no connection in human cytomegalovirus infection and BK virus infection in our study.