George Kessie

Hand Contamination with Hepatitis C Virus in Staff Looking after Hepatitis C-Positive Hemodialysis Patients

Background: Hepatitis C virus (HCV) is a major cause of hepatitis in hemodialysis (HD) patients. Routes other than blood transfusion play a role in the spread of HCV in HD patients. Molecular studies of HCV implicate nosocomial transmission of the virus in HD units. We conducted a clinicovirological study in our HD unit to investigate if the hands of dialysis personnel could represent a mode of transmission of HCV among HD patients. Methods: One liter of sterile water was used for each handwashing of dialysis personnel. The washing was collected in a sterile container and tested for HCV-RNA by polymerase chain reaction (PCR) within 3 h of collection. Eighty handwashings from nurses dialyzing HCV-positive patients (groupe A) and 100 handwashing from nurses dialyzing HCV-negative patients (group B) were tested for HCV-RNA. As a control, 60 handwashings were collected from the dialysis personnel before entering the dialysis unit (group C) and tested for HCV-RNA. Results: HCV-RNA was positive in 19 (23.75%) of samples of group A, in 8 (8%) of samples of group B (p < 0.003) and in 2 (3.3%) of samples of group C (p < 0.35). These two positive samples of group C were from nurses who had dialyzed HCV-negative patients. Conclusion: These results indicate the presence of HCV-RNA on the hands of some dialysis personnel in our HD unit, in spite fo adherence to the standard precautions. The hands of dialysis personnel are therefore a potential mode for facilitating transmission of HCV between HD patients.

New insights into hepatitis C virus infection of hemodialysis patients: the implications

The authors compared the diagnostic performance of a second-generation recombinant immunoblot assay (RIBA) (RIBA HCV 2.0 SIA) and the recently introduced third-generation RIBA (RIBA HCV 3.0 SIA) with that of hepatitis C virus (HCV) RNA by the polymerase chain reaction (PCR) in 55 patients on chronic hemodialysis. Compared with HCV RNA by PCR, RIBA 3.0 increased the sensitivity of HCV detection to 72% as compared with 56% of RIBA 2.0. Both assays underestimated the prevalence of HCV infection as determined by PCR. However, RIBA HCV 3.0 outperformed RIBA HCV 2.0, detecting all of the RIBA 2.0-positive patients plus an additional eight (8 of 22 RIBA 2.0 negative; confidence interval [CI] = [17.2%, 59.3%]). Forty-three of 51 patients with positive RIBA 3.0 or positive HCV RNA by PCR underwent a liver biopsy. Thirty (70%) had chronic hepatitis (three with cirrhosis), 10 (23%) had nonspecific changes, and three (7%) had normal liver histology. Thirty of 37 patients (81%) with hepatitis C viremia and positive anti-HCV had chronic hepatitis, whereas none of the viremic patients with negative anti-HCV had chronic hepatitis. Among the reactive antigens on RIBA 3.0, c33c was found to be most predictive of chronic hepatitis (P = 0.0002). Detection of HCV RNA continues to be the method of choice in the early phase of HCV infection. In places where a validated HCV RNA assay is not available, RIBA HCV 3.0 (soon to be commercially available) is a better alternative. Early detection of HCV infection and the implementation of an isolation strategy might be important in preventing the spread of HCV infection among hemodialysis patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Chorea as a presentation of herpes simplex encephalitis relapse

Three infants, ages 3 months to 3 years, presented with chorea as the initial manifestation of herpes simplex encephalitis (HSE) relapse. Patient 2, treated with repeated 10 day courses of 30 mg/kg/day of acyclovir, had no clear improvement in neurological status. Patient 1, treated with a repeated 10-day course, improved only to have another HSE relapse 4 years later. Patient 3 clearly improved soon after a 3-week course of acyclovir at conventional dosages. A fourth patient (Patient 4) who relapsed with chorea after what was thought to be HSE, and who did not respond to repeated acyclovir treatment, was negative for herpes simplex virus indicators on brain biopsy and DNA testing. We recommend treating all patients suffering from HSE with a minimum 3-week course of acyclovir at 30-35 mg/kg/day in 3 divided doses.

GENOTYPING OF HEPATITIS C VIRUS ISOLATES FROM SAUDI PATIENTS BY ANALYSIS OF SEQUENCES FROM PCR-AMPLIFIED CORE REGION OF THE VIRUS GENOME

We investigated the genotype distribution of hepatitis C virus (HCV) among Saudi patients with chronic hepatitis C. Serum specimens from 119 native Saudi Arabian patients with chronic hepatitis C, as documented by serology and polymerase chain reaction (PCR) for HCV RNA, were used. Genotyping was performed by reverse transcription-PCR, using specific primers at the core region of HCV genome, and DNA sequencing of the resultant amplicons. It was found that the majority of samples (47.9%) belong to genotype 4, followed by subtype 1b (16.8%), and subtype 1a (10.1%). Twenty samples (16.8%) were not able to be typed by our method. We confirmed the results by cloning at least one PCR amplicon from each genotype, and determining the nucleotide sequence of the clones. Our findings suggest that genotype 4 is the most common among native Saudi Arabian patients with chronic hepatitis C infection. Genotypes 1b and 1a were also prevalent.

Serological diagnosis of hepatitis C virus in patients with liver disease in Saudi Arabia Evaluation of antibody determination by recombinant immunoblot assays in relation to RNA detection by polymerase chain reaction

Sera from 164 Saudi Arabian patients with non-A, non-B hepatitis liver disease were examined for antibodies to hepatitis C virus (HCV) by second- and third-generation recombinant immunoblot assay (RIBA-2 and RIBA-3) and for HCV RNA by polymerase chain reaction (PCR). By using RIBA-2, 92 (56.1%) were reactive, 64 (39%) were nonreactive, and 8 (4.9%) were indeterminate. By using RIBA-3, 98 (59.7%) were reactive 60 (36.6%) were nonreactive, and 6 (3.7%) were indeterminate. By using PCR, 108 (65.9%) were positive. Of the eight RIBA-2 indeterminate samples, seven became RIBA-3 reactive but PCR-positive, and one became RIBA-3 nonreactive but PCR-negative. Of the six RIBA-3 indeterminate samples, five were RIBA-2 nonreactive but PCR-positive, and one was RIBA-2 reactive but PCR-negative. From our study on Saudi patients, we conclude that RIBA-3 has slightly but not significantly improved the results of anti-HCV antibody detection, and is probably of more value to resolve those indeterminate samples by RIBA-2. Although expensive, PCR remains the most reliable HCV diagnostic method until an HCV antigen detection test is available.

Quasispecies of genotype 4 of hepatitis C virus genomes in Saudi patients managed with interferon alfa and ribavirin therapy

Background and Objectives : Many patients with hepatitis C virus (HCV) infection do not respond to antiviral treatment, possibly due to viral quasispecies. We aimed to investigate whether the quasispeices population could be used as a predictor of response to therapy in our patients. Methods : The quasispecies of HCV genotype 4 (HCV-4) were studied in 25 naïve Saudi patients at zero, three, and six months following interferon alfa and ribavirin combination therapy. Hypervariable region 1 within the E2/NS1 gene of the virus was analyzed by the single-strand conformation polymorphism (SSCP) technique after amplification. Results : Pretreatment DNA bands by SSCP (2-7 bands) were detected in all patients. In those who achieved a complete virological response within six months (viral load < 0.2 Meq/mL; n=7), bands ranged from 2-6 (mean = 3.71±1.25). In six of these seven patients, the number of SSCP bands remained either the same or decreased sequentially. In those patients who did not respond (viral load >0.2 Meq/mL; n=18), the bands also ranged from 2-7; mean 3.77±1.73. In six of these non-responding patients, the SSCP bands remained the same or decreased sequentially. There was no significant difference between pretreatment quasispecies composition and response (P=.53). Two of the four patients with pretreatment high viral load and the same or decreased composition of quasispecies bands responded to the therapy. Conclusion : Quasispecies in our studied patients cannot be used to predict responsiveness to treatment, but may offer an explanation for failure of most HCV-4 patients to respond to interferon alfa and ribavirin therapy.

Processing of envelope polypeptides of Herpes simplex virus type 1: Demonstration of variation in different cell lines by high-performance liquid chromatography and radioimmunoprecipitation

[35S]Methionine-labelled envelope polypeptides of herpes simplex virus type 1, strain F, propagated in mammalian cell culture of various origins, were separated by ion-exchange high-performance liquid chromatography on a TSK DEAE-3SW column. Analysis of the fractions by radioimmunoprecipitation followed by sodium dodecyl sulphate polyacrylamide gel electrophoresis of the immunoprecipitates showed similarities as well as distinct differences in the number, migration patterns and molecular mass of the synthesized polypeptides, depending on the host cell. The results show that this method can be used to demonstrate species-specific or organ-specific differences in the processing of virus-specified polypeptides synthesized in host cells.

Detection of herpes simplex virus DNA in cerebrospinal fluid of Saudi pediatric patients with encephalitis by the polymerase chain reaction.

Twelve samples of cerebrospinal fluid (CSF) from Saudi pediatric patients with suspected encephalitis were found negative for herpes simplex virus by cell culture and by nucleic acid hybridization using(32)P-labeled specific probes. After amplification of DNA extracted from 100 microl of each sample using primers for the glycoprotein D gene of HSV, seven specimens were found positive for HSV DNA. Subsequent hybridization with the labeled DNA probe ensured the positivity of the seven samples and further detected one more positive sample, for a total of eight HSV DNA positive cases. This technique improved the detection of HSV in CSF samples and may assist in an early diagnosis for HSV ecephalitis.