Prevalence of Transmitted Drug Resistance among HIV-1 Patients in the Aegean Region: Results from the Western Part of Turkey

OBJECTIVES

This study aimed to analyze the antiretroviral drug resistance in antiretroviral treatment-naïve HIV-positive patients in the Aegean Region of Turkey from 2012 to 2019.

METHODS

The study included 814 plasma samples from treatment-naïve HIV-positive patients. Drug resistance analysis was performed by Sanger sequencing (SS) between 2012-2017 and by next-generation sequencing sequencing (NGS) between 2018-2019. SS was used to analyze resistance mutations in the protease (PR) and reverse transcriptase (RT) gene regions using a ViroSeq HIV-1 Genotyping System. PCR products were analyzed with an ABI3500 GeneticAnalyzer (Applied Biosystems). The sequencing of the HIV genome in the PR, RT, and integrase gene regions was carried out using MiSeq NGS technology. Drug resistance mutations and subtypes were interpreted using the Stanford University HIV-1 drug resistance database.

RESULTS

Transmitted drug resistance (TDR) mutation was detected in 34/814 (4.1 %) samples. Nonnucleoside reverse transcriptase inhibitor (NNRTI), nucleoside reverse transcriptase inhibitor (NRTI), and protease inhibitor (PI) mutations were identified in 1.4 % (n =12), 2.4 % (n =20), and 0.3 % (n = 3) of samples, respectively. The most common subtypes were B (53.1 %), A (10.9%), CRF29_BF (10.6%), and B + CRF02_AG (8,2%). The most common TDR mutations were E138A (3.4%), T215 revertants (1.7%), M41L (1.5%), and K103N (1.1%).

CONCLUSION

Transmitted drug resistance rate in the Aegean Region is compatible with national and regional data. Routine surveillance of resistance mutations may guide the safe and correct selection of initial drug combinations for antiretroviral therapy. The identification of HIV-1 subtypes and recombinant forms in Turkey may contribute to international molecular epidemiological data.

Investigation of drug resistance against protease, reverse transcriptase, and integrase inhibitors by next-generation sequencing in HIV-positive patients

Our aim was to investigate the mutations in protease (PR), reverse transcriptase (RT), and integrase (IN) gene regions in human immunodeficiency virus (HIV) using a single amplicon via next-generation sequencing (NGS). The study included plasma samples from 49 HIV-1-positive patients, which were referred for HIV-1 drug resistance testing during 2017. A nested polymerase chain reaction (PCR) was performed after the RNA extraction and one-step reverse transcription stages. The sequencing of the HIV genome in the PR, RT, and IN gene regions was carried out using MiSeq NGS technology. Sanger sequencing (SS) was used to analyze resistance mutations in the PR and RT gene regions using a ViroSeq HIV-1 Genotyping System. PCR products were analyzed with an ABI3500 GeneticAnalyzer (Applied Biosystems). Resistance mutations detected with NGS at frequencies above 20% were identical to the SS results. Resistance to at least one antiretroviral (ARV) drug was 22.4% (11 of 49) with NGS and 10.2% (5 of 49) with SS. At least one low-frequency resistance mutation was detected in 18.3% (9 of 49) of the samples. Low-frequency resistance mutations resulted in virological failure in only one patient. The cost of the analyses was reduced by sample pooling and multiplex analysis using the MiSeq system. This is the first study in Turkey to use NGS technologies for the detection of resistance mutations in all three gene (PR, RT, IN) regions using a single amplicon. Our findings suggest that NGS is more sensitive and cost-effective than the SS method.

[SARS-CoV-2 and Microbiological Diagnostic Dynamics in COVID-19 Pandemic]

We have been introduced to "Coronavirus Disease 2019 (COVID-19)" disease with high mortality and transmission rate caused by a novel human coronavirus, in December 2019 and the microbiological diagnosis of the infection has been in the center of the focus to control the pandemic. It is necessary to understand the dynamics of the virus which was classified among the severe acute respiratory syndrome (SARS) related coronaviruses and named as SARS coronavirus 2 (SARS-CoV-2), to manage testing in the right strategy and for interpretation of the results. However, much remains unclear about the virus and the immune response. SARS-CoV-2, which is an enveloped, RNA virus has been shown to attach to the host cell receptor angiotensin converting enzyme 2 with spike (S) protein and membrane fusion is provided by transmembrane protease serine 2 (TMPRSS2) of the host cell. The most commonly used and reliable test for diagnosis of COVID-19 is reverse-transcribed polymerase chain reaction (RT-PCR) performed by using nasopharyngeal swabs or other respiratory tract specimens. Viral RNA is usually detected two three days before the onset of symptoms and in the first week from upper respiratory tract samples. If possible, the lower respiratory tract specimens are preferable in the second week, especially if former PCR is negative and pneumonia has developed. The clinical sensitivity of SARS-CoV-2 RNA tests has been reported around 55-75%. Negative RT-PCR test result does not exclude COVID-19 or SARSCoV-2 infection. It should also be noted that viral RNA positivity is not an evidence of active or infectious virus. SARS-CoV-2 infection can be also detected indirectly by testing the host specific immune response to the virus. There is an increasing interest in the use of SARS-CoV-2 antibody tests both for the diagnosis and public health surveillance. However, the antibody tests should not be used as the sole test for diagnosis and case management. Antibody tests are valuable tools in seroepidemiological studies. Anti-SARS-CoV-2 IgM, IgA and IgG antibodies have been shown to be detectable as early as 5th-14th days after the onset of symptoms and most of them become positive on the 21st day. False positivity has been reported more frequently with IgM and IgA tests due to low specificity. It was shown that clinical sensitivity of the diagnostic approach increases when RNA and total antibody tests were integrated as co-tests, especially after the second week of the disease. Specificity, sensitivity, positive and negative predictive values are needed to be evaluated with large and standard studies targeting populations with different prevalences. It is also necessary to create evidence with larger seroconversion studies. In this review article, the information and data obtained until today about SARS-CoV-2 and its microbiological diagnosis have been discussed.

[Investigation of congenital CMV infection with the presence of CMV DNA in saliva samples of new born babies]

Cytomegalovirus (CMV), is the most common cause among congenital infections and is the most seen etiology in long-term sensorineural hearing loss (SNHL) and neurological impairment. Congenital CMV infection (CCMV) was reported in 0.15-2.2% of live-borne neonates in studies from different countries. A significant proportion of infected infants are asymptomatic after birth and might only be detected by routine screening methods during the new born period. The aim of this study was to screen the saliva of live-born neonates with areal-time PCR based method for the detection of CCMV in our hospital. Saliva samples collected in half an hour after birth by dry dacron swabs and were evaluated for CMV DNA (Rt-PCR, Abbott Molecular USA) from 1000 babies born in Ege University Faculty of Medicine Hospital Obstetrics Clinic between October 2015-October 2017. For the confirmation of CCMV, saliva positive newborns were evaluated with the same method for CMV DNA from their urine or blood within 21 days. All newborns were screened for sensorineural hearing tests. Subjects were 497 girls (49.7%) and 503 boys (50.3%), with a mean weight of 3116.8 g and mean of 37.61 birth week. CMV DNA was positive in the saliva of 16 newborns (1.6%). Fourteen newborns were weakly positive for CMV DNA in their saliva and were not confirmed for CCMV infection. Congenital CMV was confirmed in only two (0.2%) with the CMV DNA results in urine and/or blood samples. One of the two newborns with CCMV was symptomatic and had a neurosensorial hearing loss. The other one was asymptomatic. Saliva samples, taken immediately after birth with a noninvasive and easy method for the detection of CMV DNA is very important for diagnosis of CCMV. Positive samples should be confirmed with CMV DNA in urine or blood samples of these newborns. In this study, detection of positivity in saliva samples that were confirmed with other samples of our newborn population for CCMV was 0.2%. The specific diagnosis for CCMV in newborns with a noninvasive and easy collecting sample is important to avoid sequelae and for public health concerns.

[Analysis of hepatitis B virus (HBV) preS1, preS2 and S gene regions from patient groups infected with HBV genotype D]

Mutations in preS and S gene regions of hepatitis B virus genome may cause immune escape and diagnostic escape HBV mutants. The aim of this study was to determine preS1, preS2 and S gene regions of HBV from HBV infected patient groups by sequence analysis and contribute to the relevant literature. Nucleic acid sequence analysis of preS and S genes of HBV PCR products from 56 archived plasma samples sent to Ege University Faculty of Medicine Medical Microbiology Department Molecular Virology laboratory, for HBV tests were determined by chain termination reaction. Amino acid (aa) sequences were compared with the reference sequences obtained from GenBank. Plasma samples belonged to four groups of patients: A- Chronic HBV infected patients with typical HBV serological profiles (22 samples), B- HBV infected patients with atypical HBV serological profiles (26 samples), C- HBV re-infected patients after liver transplantation (5 samples), D- Seroconversion phase following acute HBV infection (3 samples). One of two vaccine escape mutant samples was also diagnostic escape mutant; the other diagnostic escape mutant was isolated from anti-HBc positive sample. All of the sequences were determined as genotype D. HBsAg subtypes were determined as; two ayw1, six ayw3, two mix, 46 ayw2. Among the 304 codons analysed between preS 33rd and S 162nd amino acids; aa variants were determinedin 105 codons (34.5%). Sequences can be found in GenBank with accession numbers FJ001941-FJ001996. At least one aa variation was detected in 48 of 56 samples (85.7%). The amino acid variants were as follows; PreS1: A33T, A39T, P41K, D44del, D50N, T51P, D54N, L65P/M, F67L, W77T, A81S, Q82E, I84T, L85I/M, Q86H/T, L88S, A90T/V, N91K/del, A95P, S96A, T97I/A, N98K, Q100K, S101T, S109T, P110S, N114D/E, PreS2: M1V, Q2R, S5H, F8S, H9Q, Q13L, D14N, R16K, R18K, G19S/D, F22L/S, S28T, G30E, N33T, V39A, P41H/L, I42T/L, I45T, F46Y, S47L, R48K, I49T, D51V/G, P52L, A53V, L54R/G, N55K; S gene: E2D, I4F, F8L, G10A, V14A, F20S, L22del, R24K, P29L, Q30K, N40S, F41del, G44E, T45L, T46P, V47A, L49R, Q54R, P56L, S64F, P70A, M75I, C76Y, R79H, I81T, F83C, L88P, L94S, Y100F, Q101H/R, M103L, L104F, L109I/M, I110L, G112S/R, S113N/P, S114A/del, T115I, T116N, T118A/K, P120A/T, T123A, in "a" determinant; T126I, Q129H/R, T131N, M133T, Y134N, S136Y, S143L/M/T, D144E, G145A/R. Deletions were also found in all three preS/S gene regions. The highest number of aa variations were detectedin the isolated anti-HBc positive sample (in 24 codons), followed by liver transplant group (8-13 codons). Point mutation was detected in the preS2/S promoter CCAAT box. Major hydrophilic region (MHR) variants were determined in 41.1% of 56 samples. The highest number of MHR variants belonged to atypical HBV serological profile group (group B; 61.5%) and liver transplantation group with HBV re-infection (all C group). Among the diagnostic escape and immune escape mutant (anti-HBs positive) samples, reported MHR and "a" determinant mutations were detected. In conclusion, the study population carries HBV preS/S variants; MHR and "a" determinant variant rates are high among diagnostic or immune escape mutants. It is important to evaluate the mutant detection performance of HBsAg tests.

The association between Cytomegalovirus co-infection with Pneumocystis pneumonia and mortality in immunocompromised non-HIV patients

INTRODUCTION

Impact of Cytomegalovirus (CMV) co-infection pneumonia in non-HIV patients with Pneumocystis jirovecii pneumonia (PCP) is unclear.

OBJECTIVES

The aim of our study was to determine whether CMV co-infection is associated with an increased risk of mortality.

METHODS

Our study was conducted at Ege University Hospital, Turkey. We used molecular assays to diagnose Pneumocystis jirovecii in respiratory samples, and CMV in both respiratory and blood samples. We compared morbidity and mortality stratified by CMV co-infection status.

RESULTS

Between 2009 and 2015, 43 patients (mean age: 56.7 ± 15.3 years) were diagnosed with PCP. Only 3 of 43 patients had received PCP prophylaxis. We microbiologically confirmed CMV co-infection in 28 of 43 (65.1%) patients. Acute respiratory distress syndrome (ARDS) and requirement of mechanical ventilation were more common in the CMV co-infection group (P = .019 and P = .031 respectively), and duration of intensive care unit was also longer (P = .006). In univariate analyses, mortality at 30 days was higher in the CMV co-infection group as compared to the group with PCP alone (78.6% and 46.7% respectively; P = .046). In multivariate analyses, mortality was independently associated only with the presence of ARDS [OR: 6.22 95% CI 1.3-29.32] and the association with CMV co-infection was no longer significant [OR: 2.6 95% CI 0.49-13.72, P = .257].

CONCLUSION

The risk of mortality appears to be increased in the setting of CMV and PCP co-infection in HIV-uninfected immunocompromised patients. PCP prophylaxis use was lower than expected, suggesting low physician awareness of the risks of PCP in this population.

[Evaluation of viral etiology in central nervous system infections from a university hospital point of view in Izmir based on seven years data]

The serious diseases of the central nervous system (CNS); encephalitis and meningitis, have high mortality and morbidity rate especially not diagnosed and treated in time. Nucleic acid testing (NAT) is the tool of choice for viral diagnosis in CNS infections. In this study, viral etiological agents found in cerebrospinal fluid (CSF) samples sent to our university hospital virology laboratory for laboratory diagnosis of CNS infections were retrospectively evaluated and results were compared with other reports from our country. Viral etiological agents found in cerebrospinal fluid (CSF) samples sent to Ege University Faculty of Medicine Department of Medical Microbiology Virology Laboratories for laboratory diagnosis of CNS infection between 01.01.2009-31.12.2015 were evaluated retrospectively. A total of 3778 CSF tests were performed for cell culture of enterovirus (EV) in 487 samples and 3291 tests for nucleic acid testing (NAT) by real time polymerase chain reaction (PCR) in herpes simplex virus 1 (HSV1), herpes simplex virus 2 (HSV2), varicella zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), human herpes virus 6 (HHV6) and EV. VZV and EV NAT's were performed during the last one and five years period, respectively. NAT positive results for HSV1, HSV2, CMV, EBV, VZV, HHV6 and EV were 1.80% (24/1333), 0.08% (1/1333), 3.28% (19/580), 4.35% (22/506), 0.46% (1/216), 1.05% (5/478) and 3.37% (6/178), respectively. EV was isolated in 30 (6.20%) of 487 CSF samples by viral culture. Positive samples were mainly from pediatric, neurology and infectious diseases clinics as expected. The number of higher positive results were found in samples sentin december (35.3%), july (12.9%) and november (10.6%). Overall 80% of positive samples belonged to patients over 18 years old. When the results of other studies reported from Turkey are examined, although the positivity rates are generally similar, it is seen that the rates specific to certain factors are higher in selected smaller patient groups like HSV1 and EV. Rapid nucleic acid tests like multiplex PCR and microarray will provide more practical and effective laboratory diagnosis approach in CNS infections, since many more microorganisms may be causative agents.

Electrochemical DNA biosensor for the detection of TT and Hepatitis B virus from PCR amplified real samples by using methylene blue

DNA biosensors based on nucleic acid hybridization processes are rapidly being developed towards the goal of rapid and inexpensive diagnosis of genetic and infectious diseases. Electrochemical transducers are often being used for detecting the DNA hybridization event, due to their high sensitivity, small dimensions, low cost, and compatibility with microfabrication technology. In this study, an electrochemical biosensor for the voltammetric detection of DNA sequences related to the Hepatitis B virus (HBV) and TT virus (TTV) from polymerase chain reaction (PCR) amplified real samples is described for the first time. The biosensor relies on the immobilization of the 21- or 24-mer single stranded oligonucleotides (probe) related to the HBV and TTV sequences and hybridization of these oligonucleotides with their complementary sequences (target) at carbon paste electrode (CPE). The extent of hybridization between the probe and target sequences was determined by using square wave voltammetry (SWV) with moving average baseline correction and methylene blue (MB) as the hybridization indicator. As a result of the interaction between MB and the bound guanine bases of hybrid at CPE surface, the MB signal decreased, when it was compared with the MB signal, which was observed with probe modified CPE. The difference between the MB signals, obtained from the hybrid modified and the probe modified CPE is used to detect the DNA sequences of the infectious diseases from PCR amplified real samples. Numerous factors affecting the target hybridization and indicator binding reactions are optimized to maximize the sensitivity.

[Identification of enteroviruses from central nervous system infections by RT-PCR and cell culture methods]

Viruses are the major causes of aseptic meningitis and encephalitis. Enteroviruses account for more than 80% of the aseptic meningitis cases for which an etiologic agent is identified. The aims of the present study were to identify agents of enteroviral meningitis by viral culture and reverse transcriptase polymerase chain reaction (RT-PCR) methods, to evaluate the appropriateness of a commercial RTPCR kit for its use in routine laboratory, and to obtain epidemiological data about enteroviral meningitis. Sixty six cerebrospinal fluid (CSF) samples from patients with suspected viral central nervous system (CNS) infection by clinical and CSF biochemical findings, sent to Ege University Faculty of Medicine, Department of Medical Microbiology were included in the study. The CSF samples were all negative for tested bacteria, mycobacteria, fungi, herpes simplex virus and cytomegalovirus. Thirty-four (51.5%) of the samples were from female and 32 (48.5%) were from male patients. Twenty-three (34.8%) patients were children (5 months-18 years) and 43 (65.2%) were adults (19-86 years). Shell vial rapid cell culture method by using Vero, HEp-2 and RD cell lines was performed for virus isolation and the results were evaluated on 48th hours after staining the cells with fluorescein labeled polyclonal antibodies (Pan-Enterovirus Blend, Light Diagnostics, USA). Enteroviral RNA in the samples was detected by a commercial RT-PCR kit (Enterovirus Consensus Kit, Argene, France). Sixty-one (92.4%) of 66 samples from patients with suspected viral CNS infection were found to be negative for enterovirus both with RT-PCR and shell vial cell culture methods. Three samples (4.5%) were positive by shell vial culture method. In one CSF sample that was culture positive, RT-PCR was also positive. However, the remaining two culture positive samples yielded negative result by RT-PCR. Intermediate results with RT-PCR were obtained in two samples (3%) that were identified as negative by cell culture. Two of the three positive samples in cell culture were identified as echovirus, however, the remaining sample could not be identified due to small sample amount. As a result, the commercial assay was found non-practical and labor intensive, giving indeterminant results in some cases and missing two culture positive samples. Since it didn't have an advantage over the cell culture method used, it was found inappropriate for routine diagnosis in our laboratory. On the other hand, it has been known that nucleic acid amplification tests (NAT) have markedly improved the diagnosis of enterovirus infections by increasing the sensitivity compared with cell culture methods. An alternative NAT method should be evaluated in parallel with cell culture method especially in CSF samples of children with suspected viral central nervous system infections.

[Investigation of anti-HTLV I/II seroprevalence in healthy blood donors in Izmir region, Turkey]

Almost 10-20 million people in the world are thought to be infected by human deltaretroviruses, namely human T-cell lymphotropic virus (HTLV) type I and II, recently. HTLV-I is endemic in southwestern Japan, the Caribbean and sub-Saharan Africa, whereas HTLV-II is more prevalent in intravenous drug addicts, and in American indian populations, endemically. HTLV-I is mainly responsible for adult T-cell leukemia (ATL) and HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), however, HTLVII is not clearly associated with a known clinical disease. Both viruses may be transmitted by sexual contact, parenteral route, whole blood transfusion and breast-feeding. In most of the countries [USA, Canada, South America, Caribbean, Japan, Taiwan and some Europe countries (France, UK, Ireland, Sweden, Denmark, The Netherlands, Portugal, Romania, Greece)] routine screening of anti-HTLV-I/II in blood donors is mandatory, however, there is no such practice in Turkey since seroepidemiologic data on HTLVI/II infections is insufficient. In this study, the seroprevalence of HTLV-I/II in healthy blood donors admitted to the blood bank of Ege University Medical Faculty Hospital, Izmir (located at Aegean region), was investigated to support data on the decision making process on routine screening of anti-HTLV-I/II in blood centers. Serum samples from 10.000 healthy blood donors (mean age: 32.6 years; 87.8% were male), who succeeded the donor history questionnaire, were included to the study, and HTLV-I/II antibodies were screened by a commercial enzyme immunoassay (ELISA) (Murex HTLVI-II, Murex Diagnostics, UK) method. Serum samples which were yielded reactive and borderline results were retested by ELISA, and repeated reactive/borderline results were then confirmed by HTLV-I/II confirmation test (INNO-LIA HTLV-I/II, Innogenetics, Belgium). Seven samples yielded reactive/borderline reactive results by both ELISA lots, however, all of them were found negative by confirmatory test. According to our data HTLV-I/II infections are not endemic in Izmir region, and anti-HTLV-I/II screening of blood donors is not required in our blood center currently. Nevertheless, screening HIV which is very rare in prevalence among the donor population, is mandatory for blood donors in our country. Thus, even its prevalence is very low, much more comprehensive and multi-centered studies are necessary for making the decision of integrating HTLV-I/II in routine blood bank screening tests in Turkey.

The acquisition time of infection: a determinant of the severity of hepatitis C virus-related liver disease in renal transplant patients

BACKGROUND

The aim of this study was to compare the clinical and histopathological course of HCV infection acquired before and during or after renal transplantation.

METHODS

According to HCV status, 197 RT patients were divided into three groups. At the time of RT, anti-HCV antibody was positive in 47 patients (pre-RT HCV group). In 27 patients, in whom anti-HCV negative at the time of RT, anti-HCV and/or HCV RNA was found to be positive following an ALT elevation episode after RT (post-RT HCV group). Both anti-HCV and HCV RNA were negative at all times in remaining 123 patients (control group).

RESULTS

Liver biopsy was performed in 31 of 47 patients in pre-RT and 24 of 27 in post-RT HCV group after RT. Duration of follow-up was similar in all groups with a mean of 7.1 +/- 4.0 yr. Ascites and encephalopathy were seen in only post-RT HCV group (22%). Histological grade (6.5 +/- 2.7 vs. 4.1 +/- 1.4) and stage (2.0 +/- 1.5 vs. 0.8 +/- 0.8) was significantly severe in post-RT HCV group (p < 0.01). Three patients died due to liver failure in post-RT HCV group.

CONCLUSIONS

HCV infection acquired during or after RT shows a severe and rapidly progressive clinicopathological course, which is significantly different from pre-transplant anti-HCV positive patients.

Restriction fragment length polymorphism analysis and direct sequencing for determination of HBV genotypes in a Turkish population

The aim of this study was to analyze the restriction fragment length polymorphism and direct sequencing results in genotyping of hepatitis B virus from a Turkish population in a clinical virology laboratory. Serum samples of 54 chronic hepatitis B patients attending the Ege University Hospital were studied. Sequences of partial S gene PCR products were analysed and RFLP was performed. Fifty-three isolates could be identified by direct sequencing as genotype D. One sample needed to be cloned and determined as genotype D. Forty-two isolates were genotyped as D with RFLP according to published determinative patterns. Twelve isolates had undefined patterns. Eight of them suggested a mixture of isolates with different patterns and cloning of these samples confirmed the presence of heterogeneous isolates. Four isolates with undefined pattern were determined as genotype D by direct sequencing. All the studied isolates were genotype D. The results of this studied population suggest that RFLP is suitable for HBV genotyping in a routine clinical virology laboratory setting. However sequence analysis and even cloning may be needed to clarify indeterminate results.

Clinical significance of basal core promoter and precore mutations in chronic hepatitis B

BACKGROUND/AIMS

The mutations in the basal core promoter and precore region of hepatitis B virus genome in hepatitis B e antigen-positive and -negative chronic hepatitis B patients have been described. The reports about their prevalence and clinical significance in the Mediterranean region where D is the predominant genotype, are very limited.

METHODOLOGY

The serum samples were collected from 44 naive chronic hepatitis B patients. For detection of the mutations basal core promoter and precore regions of HBV genome were amplified and sequenced.

RESULTS

All samples were determined as genotype D. Before initiation of treatment basal core promoter mutations were found as 55% (11/20) and 46% (11/24) in HBeAg-positive and -negative patients, respectively (p > 0.5). HBeAg-negative samples were associated with precore mutations (G1896A and G1899A). Three of 20 (15%) patients of HBeAg-positive and seven of 24 (29%) of HBeAg-negative populations showed sustained response to therapy at the 24th month of initiation.

CONCLUSIONS

The presence of precore stop codon mutant in those with sustained response was 89%, overall at the end of therapy. At initiation of therapy basal core promoter mutations were more common in non-responders than responders (65% vs. 20%; p < 0.001). While 23% of cases totally showing sustained response, absence of mutations in the basal core promoter region of hepatitis B virus genotype D may be related to sustained response in patients with chronic hepatitis B.

Electrochemical probe DNA design in PCR amplicon sequence for the optimum detection of microbiological diseases

Direct electrochemical genosensor was developed for the detection of a probe sequence relative position in a PCR amplicon for the optimum detection of bacterial and microbiological diseases, in this study. The genosensor relies on a label-free electrochemical detection. The amino-linked inosine modified (guanine-free) coequal capture probes which were chosen from different parts of a PCR amplicon, immobilized on to disposable pencil graphite electrodes (PGE) by electrostatically and covalently. As a model case Hepatitis B virus (HBV) genome amplicon was used for the detection and specification. Hybridization was occurred after surface coverage with denatured amplicons. After hybridization, optimum probe sequence position was identified by using the differences between the responses of guanine oxidation signals. The results of this study might have a great convenience for the microbiological diseases detection applications such as DNA micro arrays.

Distribution of hepatitis C virus genotypes in patients with chronic hepatitis C infection in Western Turkey

OBJECTIVE

The primary aim of this study was to determine the recent distribution of various genotypes of hepatitis C virus (HCV) in patients with chronic HCV infection in Western Turkey. Additional objectives were to determine whether there are any associations of genotype with gender and age, and to determine the nucleotide similarities and risk factors of non-1 HCV genotypes.

METHODS

Serum samples from 345 patients (176 male, 169 female; mean age 53.3+/-12.7 years, range 10-81 years) with chronic HCV infection were analyzed in this study. Viral genotypes were determined by a restriction fragment length polymorphism (RFLP)-based in-house assay. To confirm genotypes for the samples with band patterns other than genotype 1, the 5' UTR was amplified and sequenced.

RESULTS

Genotype 1 was observed in 335 of the 345 patients (97.1%). Of these, 34 patients showed infection with subtype 1a (9.9%) and 301 with subtype 1b (87.2%). Genotypes 2, 3, and 4 were determined in 0.9%, 1.4%, and 0.6% of the patients, respectively. Patients infected with type 1 were significantly older than patients infected with non-1 genotypes; however no significant differences were recorded in gender distribution.

CONCLUSIONS

Genotypes other than genotype 1 are quite rare; these are possibly acquired in other countries. Turkish patients with chronic hepatitis C still represent a rather homogenous group with genotypic diversity encountered rarely.

[A case of chronic hepatitis B with primary adefovir resistance]

Implementation of antiviral therapy leads to the emergence of mutant strains during the treatment in chronic hepatitis B. Hepatitis B virus (HBV) with primary antiviral resistance may be rarely encountered. In this report, a chronic hepatitis B case who had never received adefovir dipivoxil but had primary adefovir resistance, was presented. HBeAg positive 25-year-old male patient was treated with interferon (IFN)-alpha (thrice a week 10 MU) and lamivudine (100 mg/daily) combination for one year. At the end of this treatment although HBV-DNA was under the detectable limit and ALT levels returned to normal, anti-HBe antibodies did not develop. During the course of lamivudin treatment on the third year virus was found to be resistant to lamivudin [FLM+YMDD+YIDD+YVDD (Inno-LiPA HBV DR, Innogenetics Ghent, Belgium)] and adefovir was added to the lamivudin therapy. At the end of eight months of combination therapy, ALT levels did not return to normal and HBV-DNA was still in detectable levels. On the 11th month resistance to adefovir was analysed and rtA181T mutation was found by DNA sequence analysis (Big Dye Terminator Cycle Sequencing kit, Applied Biosystems, USA). Since there had been no response to adefovir from the initiation of the therapy, primary adefovir resistance was suspected. Primary adefovir resistance was confirmed by the detection of the same mutation in pre-adefovir treatment serum sample of the patient. Lamivudin was re-added to the therapy, however, HBV-DNA still remained positive on the third month of this combination therapy. The patient got out of routine follow-up after this period.

Hepatitis delta virus (HDV) genotypes in patients with chronic hepatitis: molecular epidemiology of HDV in Turkey

OBJECTIVE

Analysis of hepatitis delta virus (HDV) isolates from around the world has indicated that there are at least three phylogenetically distinct genotypes with different geographic distributions. The aim of this study was to determine the distribution of HDV genotypes by direct sequencing in patients with chronic delta hepatitis in Izmir, Turkey.

DESIGN AND METHODS

Serum samples from 32 chronic hepatitis patients (21 males, 11 females; mean age 44.2 years, range 23-70 years) with anti-delta positivity were analyzed for hepatitis B and C serologies. After reverse transcription, cDNA of partial delta antigen was amplified by in-house nested PCR. The products of the HDV PCR were bidirectionally sequenced with internal primers using Big Dye Terminator DNA Sequencing Kit (Applied Biosystems, CA, USA) and ABI Prism 310 Genetic Analyzer (Perkin Elmer, USA). Nucleotide sequences of HDV were compared with previously reported sequences and aligned by using ClustalW (1.82).

RESULTS

HDV-RNA was positive in 26 (81.3%) of 32 anti-delta positive samples. Comparison of the HDV sequences with published sequences of HDV genotypes I, II, and III indicated that all were closely related to HDV genotype I isolates. Similarity among isolated sequences ranged from 84% to 96%.

CONCLUSION

HDV genotyping was successfully performed by direct sequencing of the amplicons obtained from routine HDV-RNA screening PCR tests. All of the HDV isolates from the chronic delta hepatitis patients included in this study were found to be genotype I.

Comparison of sequence analysis and INNO-LiPA HBV DR line probe assay in patients with chronic hepatitis B

The aim of this study was to compare direct sequence analysis of partial HBV pol gene and Inno-LiPA HBV DR in serum samples of 120 chronic hepatitis B patients sent to the Clinical Microbiology Laboratory of Ege University Hospital because of lamivudine resistance. Sequence analysis was performed on ABI Prism 310 Genetic Analyzer. Comparison of Inno-LiPA and sequence results obtained by double-blind evaluation showed full agreement (both at rt180 and rt204) in 58.8% of samples. Visually rechecking of the electropherograms increased this rate to 68.3% Codon based rates are 81.7% and 75.8% at rt180 and rt204 respectively. LiPA detected variants in additional 12 (10%) samples, but missed one variant sample (both rt180 and rt204) and one sample was indeterminate due to poor probe binding. LiPA allows determination of mixed variants and seems to be more sensitive and simple for routine testing even though sequence analysis is still the gold standard for detecting new variants.

[Investigation of Epstein-Barr virus DNA and RNA in tissues of patients with lymphoma]

Relation between Epstein-Barr virus (EBV) and nasopharyngeal carsinoma, Burkitt's lymphoma, and lymphomas in immunosupressed patients have been shown previously in different studies. The same relationship was also shown in Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) by some researchers. The aim of this study was to demonstrate EBV nucleic acids in tissue sections of adult patients with lymphoma. The presence of EBV encoded RNA (EBER) were investigated with in situ hybridization and EBV-DNA with PCR method in 29 formalin-fixed paraffin-embedded tissue sections (19 lymph nodes, the others being gastric, orbital, skin, salivary gland, testicle, small intestinal, tongue root, bone marrow and gingival tissues) of 8 patients with HL and 21 patients with NHL who were followed-up in Haematology Clinics of our university hospital. EBER and EBV-DNA positivity rates were found as follows respectively; 50% (n: 4) and 37.5% (n: 3) of 8 HL patients, and 23.8% (n: 5) and 47.6% (n: 10) of 21 NHL patients. In total evaluation EBER and/or EBV-DNA were positive in 5 of 8 (62.5%) HL, and 12 of 21 (57.1%) NHL tissue sections. There was no significant difference in EBER and EBV-DNA positivity between HL and NHL groups. As a result, our study emphasize a possible EBV related aetiology in HL and NHL.

Investigation of herpes simplex virus DNA in pityriasis rosea by polymerase chain reaction

BACKGROUND

Pityriasis rosea (PR) is an acute, inflammatory disease of unknown cause. Clinical and experimental findings indicate an infectious etiology of PR. Our purpose is to examine the skin lesions and blood samples of PR patients by polymerase chain reaction (PCR) for the presence of HSV type 1 and 2 DNA.

METHODS

The lesional skin biopsies from 10 patients and blood samples from two randomized patients with clinically and histologically confirmed pityriasis rosea were examined by PCR.

RESULTS

No HSV 1 and HSV 2 DNA was detected in the lesional biopsy and blood samples.

CONCLUSIONS

We could not identify a relationship between HSV 1, HSV 2 and PR.

[Evaluation of the agreement of results obtained from ABI Prism 7000 and 7700 sequencers in the quantification of hepatitis B virus DNA]

There are different methods and systems for quantification of HBV-DNA in clinical virology laboratories. The aim of this study was to evaluate the agreement of the polymerase chain reaction (PCR) protocol with ABI Prism 7000 instrument (PE Biosystems) which was designed and optimised for ABI Prism 7700 (PE Biosystems). Serum samples obtained from 168 chronic hepatitis B patients were treated with "High Pure Viral Nucleic Acid Kit" (Roche Applied Science, USA), and MagnaPure LC isolation station (Roche Applied Science, Germany) was used for HBV-DNA isolation. Real time PCR procedure which amplifies pre-S gene of HBV genome was performed. Amplification and detection steps of all samples were performed with ABI Prism 7700 and 7000 Sequence Detection Systems. Among 168 samples, results of 124 serum samples were found to be in dynamic ranges of the tests. The results of these 124 samples obtained from ABI 7000 and ABI 7700 were concordant. Among the rest of 44 samples; one yielded higher than 10(10) copies/mL with two of the systems; six samples gave results higher than 10(10) copies/mL only with 7700; thirty samples were found negative with both of the systems; seven samples were positive (320-1220 copies/mL) with 7000 but negative with 7700. As a result this PCR protocol can be used in ABI 7000 system according to viral quality control (VQC) results. However, since the results of samples with HBV-DNA less than 1 x 10(6) copy/ml were discordant with the results obtained by ABI 7700 system, it can be concluded that different systems must not be used for the management and monitoring of the same patient.

HBV vaccination in liver transplant recipients: not an effective strategy in the prophylaxis of HBV recurrence

Anti-HBs immunoglobulins (HBIG) and lamivudine are main options to prevent hepatitis B virus (HBV) reinfection after liver transplantation. Although they are very effective, development of mutant viruses and high cost of treatment are main limitations for their application. Additionally there is an uncertainity for the duration of that prophylaxis regimen and its mostly applied indefinitely. Recently, post-transplant HBV vaccination is reported to be a cheaper alternative prophylaksis strategy, that enables discontinuation of HBIG. To investigate the efficacy of HBV vaccination in patients transplanted for HBV cirrhosis, we administered double course of double dose recombinant HBV vaccine (Genhavac B; containing HBV pre-S1, pre-S2, and S gene products). Vaccination has been started 1 month after HBIg discontinuation, and lamivudine (100 mg/day) was given throughout the study. The first cycle consisted of 0, 1- and 6-month schedule, and, in nonresponders, second cycle 0, 1-, 2-month schedule. Fourteen patients included into the study. Only one patient seroconverted (an anti-HBs titre of 37 IU/L) after the first cycle. No other patient responded to second cycle. HBV vaccination in the post-transplantation setting does not seems like an effective strategy in the prophylaxis of HBV recurrence.

Rotavirus gastroenteritis among children under five years of age in Izmir, Turkey

Little is known about the epidemiology of rotavirus infection in Turkey. The aim of the study was to determine the incidence and clinical significance of rotavirus gastroenteritis, in view of the potentially available prevention by rotavirus vaccination. The study also sought to determine possible risk factors for rotavirus gastroenteritis. Therefore, 920 children under five years of age with acute gastroenteritis admitted to three pediatric hospitals in Izmir were studied. Rotavirus was identified in 39.8% of the children. Most children with rotavirus gastroenteritis (80.7%) were younger than two years of age. Marked seasonality of rotavirus gastroenteritis was observed, with a peak incidence from January to March. A total of 91% of rotavirus strains that were typed were of serotypes G 1-4. There was no significant difference among rotavirus-positive and rotavirus-negative patients with regard to family income. Compared with children who were exclusively breast-fed, those who were not exclusively breast-fed were at a two-fold greater risk of rotavirus diarrhea. Rotavirus gastroenteritis was significantly more severe than non-rotavirus gastroenteritis; 69% of children with rotavirus infection had severe gastroenteritis (score > or = 11). In conclusion, rotavirus is the most common cause of severe gastroenteritis among children under five years of age in Izmir. A new potent rotavirus vaccine, when available, will provide effective protection against severe rotavirus infection. Promotion of breast-feeding would augment the impact of rotavirus vaccines in preventing severe childhood diarrhea.

Anti-HTLV-I/II Seroprevalence in Healthy Blood Donors in İzmir, Turkey

Human T-cell lymphotropic virus type I (HTLV-I) is the first human retrovirus to be associated with malignant disease-namely, adult T-cell leukemia/lymphoma. HTLV-I has also been associated with several diseases. HTLV-I has a worldwide distribution with major endemic foci in the Caribbean and Southern Japan. HTLV-II is a closely related retrovirus that shares considerable genomic homology with HTLV-I but has not been proven to be a pathogen. Major routes of transmission are blood transfusion, breast milk and sexual activity. In this study, we examined the seroprevalance of HTLV-I/II among healthy blood donors attended to Ege University Hospital in Izmir. 913 healthy blood donors were examined for the presence of anti-HTLV-I/II antibody in their sera. Serum specimens were tested with an enzyme immunoassay (EIA) (Organon Teknika, Vironostika HTLV-I/II Microelisa System, Holland). All of the 913 healthy blood donors were seronegative with EIA. These findings indicate that screening of blood donors for HTLV I/II is not necessary at present time.

Failure to detect Chlamydia pneumoniae DNA in cerebral aneurysmal sac tissue with two different polymerase chain reaction methods

OBJECTIVE

Chlamydia pneumoniae (C pneumoniae) is a common cause of a usually mild, community acquired pneumonia. This organism, however, can spread from the respiratory tract into other parts of the body and has been detected in up to 70% of atheromatous lesions in blood vessels. Although the exact mechanism of the C Pneumoniae contribution to the pathogenesis of atherosclerosis remains unknown, prophylactic antibiotic trials are planned for people at high risk for coronary disease.

METHOD

In this study the authors aimed to investigate C pneumoniae DNA content in the cerebral aneurysmal sac tissue with the aid of polymerase chain reaction (PCR) method. C pneumoniae DNA was searched in 15 surgically clipped and removed aneurysmal sac tissue and in two tumour (an ependymoma of the fourth ventricle and a craniofaringoma) samples by touchdown enzyme time release PCR (TETR PCR) targeting 16S rRNA gene and by nested PCR targeting ompA gene.

RESULTS

Both PCR methods were sensitive to detect in C pneumoniae 4x10(-2) genomes. C pneumoniae DNA was not detected in any of the 17 sample tissues of these patients.

CONCLUSION

The contribution of C pneumoniae in the development of intracranial aneurysms cannot be excluded despite the results of this study. Further studies on the possible role of C pneumoniae or any other micro-organisms in the pathogenesis of aneurysms should be performed.

Nosocomial hepatitis C virus infection in a renal transplantation center

Nosocomial hepatitis C virus (HCV) infections were recorded in the renal transplantation unit of the university hospital. There were cases of acute HCV infection with aggressive clinical courses diagnosed from a positive HCV RNA test in the early post-transplantation period and which remained anti-HCV negative. Their anti-HCV seronegativity was attributed to them having acquired HCV under intense immunosuppressive therapy and suggested that the aggressive clinical course could be due to the deficient immune response resulting in an inability to limit viral replication. There were also donors diagnosed as having acute HCV infection in the early post-operative period. Genotyping and sequence analysis for HCV were performed on the isolates of eight of these patients who were consecutively transplanted and of three donors whose recipients were infected with HCV prior to transplantation, and who acquired acute HCV infection after transplantation. Of the eight recipients in the first group three were genotype 1a, three were genotype 1b, one was genotype 3a, and the last one was genotype 4 according to Simmond's classification. Of the three donor-recipient couples both the HCV isolates from one couple were genotyped as 1b and the phylogenetic analysis indicated that the patients were infected with a common variant of HCV, but the genotypes of HCV isolates from the other couples were different. Recipients were genotype 1b and the donors were genotype 1a in these couples. Genotype results of the first group and donor-recipient couples, and sequence analysis of genotype 1b and 1a isolates, showed that the source of infection was not a unique strain and there were multiple breaks in universal precautions while managing these patients.

TT virus infection and genotype distribution in blood donors and a group of patients from Turkey

BACKGROUND

TT virus (TTV) DNA has been found in a large proportion of patients with different forms of non-A-G hepatitis, however the clinical importance is unclear. We aimed to determine the genotypes of TTV isolates found in blood donors and different patient groups from the western part of Turkey.

MATERIALS AND METHODS

TT DNA was investigated in serum samples of 91 volunteer blood donors (BD), 105 thalassemia (TH) patients, ten patients with fulminant hepatitis (FH) and 16 hemodialysis (HD) patients by heminested PCR using primers NG059, NG061 and NG063 from the ORF1 region. 39 isolates were genotyped by analyzing the partial sequence of ORF1.

RESULTS

TTV DNA was found in 75% of HD, 80% of FH, 61% of TH patients and in 51.6% of BD. Among the sequenced isolates, 14 (35.9%) belonged to genotype 1 (G1) and 25 (64.1%) belonged to genotype 2 (G2). Among the G2 sequences, 22 were grouped as G2c.

CONCLUSION

TTV infection was common in the population studied, even with moderately sensitive primers. G2 was the major genotype of the studied population without any significant differences in distribution between various patient groups and BD.

Low-dose intramuscular hepatitis B vaccination in medical students: 4-year follow-up

BACKGROUND

This is a report on the results of immunization of medical students with low-dose hepatitis B (HB) vaccine prior to starting clinical practice and evaluation of the efficacy of this vaccination scheme.

MATERIALS AND METHODS

Low-dose (2 microg) recombinant HB vaccine was administered intramuscularly (im) at months 0, 1, 2 and 12 to 105 volunteers who wee HB surface antigen (HBsAg) and anti-HB core antigen (HBc) negative. Additional doses were administered after the third dose to the vaccines with anti-HBs titers below 10 IU/l.

RESULTS

Protective anti-HBs levels (above 10 IU/l) were obtained in 73.3%, 95.6%, 100% and 92.8% of vaccines with geometric mean titers of 91, 61.6, 3,662 and 367 IU/l at months 3, 12, 13 and 44 months, respectively.

CONCLUSION

Long-term effective protection against HB could be obtained in medical students with this scheme. Low-dose HB im vaccination can be utilized as a cost-saving vaccination strategy.

Clinicopathological features of hepatitis C virus infection in dialysis and renal transplantation

BACKGROUND

Liver biopsy (LB) gives an accurate picture of the severity of hepatitis C virus (HCV) infection in end-stage renal disease. The aim of this study was to find out whether clinical and histopathological course of HCV infection in renal transplant (RT) patients (pts) is different from dialysis (Dx) pts.

METHODS

Forty Dx and 46 RT pts underwent LB. Clinical and biochemical data were retrospectively collected from medical charts. ALT level above the upper limit was described as elevated. LB was done regardless of the ALT level. LB specimens were examined using a semiquantitative scoring system locally modified from Scheuer. Histological activity (grade) and fibrosis (stage) were scored separately.

RESULTS

ALT was elevated in 65% of Dx pts. At the time of LB 30% of Dx pts had elevated ALT and 95% were viremic. Normal/minimal inflammation was detected in 25% of LBs, chronic hepatitis in 72.5%, cirrhosis in 2.5%. Stage and grade were respectively 1.08 +/- 1.02 and 4.30 +/- 2.98. Normal/minimal inflammation was detected in 9% of the 46 RT pts, chronic hepatitis in 84%, cirrhosis in 7%. Stage and grade were respectively 1.74 +/- 1.1 and 5.39 +/- 2.21. Although there was no significant difference in the histological grade between Dx and RT pts, histological stage was significantly higher in RT pts than Dx. The frequency of cirrhosis, hepatitis and normal inflammation was similar in the two groups.

CONCLUSION

Histopathological liver injury due to HCV infection seems to be more severe in RT than Dx pts but this does not seem to be clear at the clinical and biochemical level. Sequential histopathological assessment and longer follow-up will be required to clarify this issue.

Low-dose intradermal administration of recombinant hepatitis B vaccine in children: 5-year follow-up study

Several studies have documented the efficacy of low-dose intradermal administration of hepatitis B vaccine. However, little is known about the duration of protection provided by low-dose intradermal administration of hepatitis B vaccine. This study reports results from a 5-year follow up period of 200 healthy children (100 infants and 100 preschool children) immunized intradermally with 2 microg doses of recombinant hepatitis B vaccine (GenHevac B) at months 0,1, and 6. In the 8th week after the third vaccine dose, 97% of the children developed anti-HBs antibodies higher than or equal to 10 mlU ml(-1), and the antiHBs geometric mean titre (GMT) was 676 mlU ml(-1). In month 18 and year 5, the anti-HBs GMT decreased to approximately one-third (220 mlU ml(-1)) and one-tenth (68 mlU ml(-1)) of the initial levels, respectively. However, 87% of the children had protective levels of anti-HBs (> or =10 mlU ml(-1)) after 5 years. Among 156 children followed for 5 years, none became positive for anti-HBc and/or HbsAg. Seven children who were seronegative after 5 years developed anti-HBs antibodies higher than 1000 mlU ml(-1) after an additional 10 microg intramuscular hepatitis B vaccine. Persistent immunologic memory over periods of 5 years or more is evident, the anamnestic antibody response to a booster dose of vaccine, even in these children who have lost antibody. We conclude that intradermal administration of 2 microg recombinant hepatitis B vaccine provides long-term protection against hepatitis B virus in infants and preschool children.

Diagnosis of hepatitis C virus (HCV) infection and laboratory monitoring of its therapy

BACKGROUND

Just after the identification and characterization of hepatitis C virus (HCV) in 1989, tests for the detection of HCV antibodies or HCV RNA in serum were developed. The enzyme-linked immunosorbent assays (ELISAs) and confirmatory/supplemental analytical antibody tests were improved in sensitivity and specificity with the development of further generations of these assays. Application of molecular tests for detecting, quantifying, and characterization of the infecting virus became very important in management of HCV infection.

OBJECTIVE AND DESIGN

This review summarizes the assays developed for the diagnosis and management of HCV infection. Strategies for the diagnosis and monitoring with the advantages and disadvantages of the assays based on the setting and goal are discussed according to data in the literature and our experience.

RESULTS

Specific laboratory diagnostic tests for hepatitis C virus infection may be discussed under two titles: (i) Serological antibody tests which detect anti-HCV in serum or plasma; (ii) Molecular tests which detect HCV RNA genome, investigate viral load, and determine the characteristics of the genome. Strategies in different laboratory settings which screen populations with different HCV prevalences vary.

CONCLUSIONS

Anti-HCV positive result in a low-risk setting such as blood banks should be confirmed with an analytical antibody test. Then a HCV RNA test should be performed on serum of the person with a positive or indeterminate confirmatory test result. On the contrary, anti-HCV positive test result in high-risk population or a situation where HCV infection is suspected, it is likely to be true positive and confirmation with HCV RNA test will be significant. Quantitative HCV RNA test and genotyping should be performed if therapy is considered.

Clinicopathological features of rapidly progressive hepatitis C virus infection in HCV antibody negative renal transplant recipients

BACKGROUND

Hepatitis C virus (HCV) infection acquired during dialysis treatment generally shows a relatively benign course after renal transplantation (RTx). However, less is known about the course of HCV infection acquired during or after RTx.

METHODS

Clinical and histopathological assessment of 15 renal transplant recipients who acquired HCV infection during or after RTx.

RESULTS

Alanine aminotransferase levels rose for the first time 1-19 weeks after RTx. HCV RNA was found positive in all patients, but anti-HCV became positive in only nine of them. During a mean follow-up of 21 +/- 12 months, jaundice appeared in 12 patients while ascites and/or hepatic encephalopathy occurred in six. Azathioprine was stopped in all patients. Cyclosporin was also stopped in four patients and in two of them prednisolone was also interrupted for a period of 3-7 weeks. Following this, ascites, hepatic encephalopathy and biochemical disturbances improved, while no deterioration was seen in graft function. Nine of the 15 patients had undergone two consecutive liver biopsies (LB). The first LB revealed cirrhosis in three and chronic hepatitis in six patients; the second LB showed cirrhosis in seven patients. The histological activity index (Knodell's score) progressed from 11.8 +/- 3.5 to 13.8 +/- 3.8.

CONCLUSIONS

The results suggest that HCV infection acquired during or after RTx may run an unusual and rapidly progressive clinical and histopathological course at least in some of these patients. Decrease or withdrawal of immunosuppressive drugs may improve early hepatic failure without detrimental effect on graft function during that period.

Low-dose intradermal versus intramuscular administration of recombinant hepatitis B vaccine: a comparison of immunogenicity in infants and preschool children

Two hundred infants and two hundred preschool children were randomly assigned to receive either 10 micrograms of recombinant hepatitis B vaccine (GenHevac B) intramuscularly (i.m.) or 2 micrograms intradermally (ID) in the deltoid region at 0, 1 and 6 months. Antibody to hepatitis B surface antigen (anti-HBs) was tested eight weeks after the third vaccine dose. Standard dose i.m. and low-dose ID administration of recombinant hepatitis B vaccine produced comparable rates of anti-HBs equal to or higher than 10 mIU ml-1 in infants (98% and 94%, respectively) and preschool children (98% and 100%, respectively). Although i.m. vaccination produced higher anti-HBs concentrations than ID vaccination both in infants (geometric mean titre-GMT, 935 versus 621 mIU ml-1) and preschool children (GMT, 1393 versus 804 mIU ml-1), the differences were not statistically significant (p > 0.05). The preschool children tended to have higher anti-HBs concentrations than the infants. No clinically serious adverse effects were observed in both vaccine groups; however, induration and hyperpigmentation at the injection site were more often seen in the study population that was vaccinated intradermally. We conclude that intradermal administration of 2 micrograms recombinant hepatitis B vaccine is safe and effective in infants and preschool children, and may be an acceptable, less expensive alternative to full-dose i.m. vaccination for mass immunization, especially in developing countries.

Screening for human immunodeficiency virus type 1 and 2 in a Turkish blood donor population

OBJECTIVES

To determine the prevalence of human immunodeficiency virus-1 and -2 infection in voluntary blood donors at a university hospital in the third largest city of Turkey and to evaluate the HIV testing strategy for notifying blood donors.

METHODS

Between July 1995 and August 1997, 36,373 voluntary blood donors who met the criteria for donating blood were tested for the presence of HIV-1 and -2 antibodies by using an automated enzyme-linked fluorescent immunoassay. Repeatedly reactive samples were subjected to a different enzyme-linked immunosorbent assay (ELISA) and a line immunoassay (LIA) for the detection of antibodies.

RESULTS

Of the 36,373 samples tested 72 were found to be repeatedly reactive or borderline by the first screening enzyme immunoassay (EIA). None of the 72 samples was reactive by the second EIA. These samples were further tested by LIA: 64 were negative on the line immunoassay and 8 were indeterminate. Three of eight donors who had indeterminate results by LIA were tested for HIV-1 DNA by polymerase chain reaction (PCR) and were found to be negative. One additional donor with an indeterminate LIA was found to be negative by EIA and LIA during the 6-month follow-up period.

CONCLUSION

Donor questioning, repeat EIA testing, LIA testing, and HIV-1 DNA analysis did not confirm evidence for HIV infection among this blood donor population. Blood donor notification of test results according to the World Health Organization (WHO) strategy III was found to be an appropriate approach.

Intradermal administration of hepatitis B vaccine in infants and preschool children

One of the ways to administrate hepatitis B vaccination is the intradermal (id) route. The aim of this study is to evaluate the immunologic response of various age groups of children who received three 2 micrograms id doses of recombinant hepatitis B vaccine. One hundred and eighty-seven children (86 infants, 101 preschool children) were administered a 2 micrograms dose of recombinant hepatitis B vaccine (Gen Hevac B) intradermally zero, one and six months. Eight weeks after the third vaccination, the geometric mean titers (GMT) of antibody to hepatitis B surface antigen (anti-HBs) of infants was 753 IU/L; that of preschool children was 799 IU/L. There was no statistically significant difference between the anti-HBs GMT of infants and preschool children. However, infants were less likely to have developed protective anti-HBs (< or = 10 IU/L) than preschool children (93% vs 100%, p = 0.009). In 8.1 percent of infants and 3.9 percent of preschool children, local reactions were observed. The 2 micrograms recombinant vaccine by id route is safe and suitable for immunization of preschool children. The id route is technically difficult to administrate in infants and protective seroconversion rates are lower than in preschool children.

DNA insitu hybridization in the diagnosis of human papillomavirus infection

BACKGROUND

Certain types of human papillomavirus (HPV) are shown to be associated with the development of genital lesions. DNA hybridization methods are used for the diagnosis of HPV infections.

OBJECTIVE

To use a nonradioactive DNA in situ hybridization system for the investigation of HPV infections responsible for the development of genital lesions in women.

STUDY DESIGN

Sections from archival paraffin embedded biopsy specimens of 59 cases were screened for the presence of HPV DNA sequences by using digoxigenin labeled DNA probe which is specific for all types of HPVs and digoxigenin detection system. The study group consisted of samples diagnosed as squamous hyperplasia of the vulva (group 1), koilocytosis (group 2), condyloma acuminatum/koilocytotic atypy (group 3), cervical intraepithelial neoplasia (CIN), and epidermoid carcinoma (group 4).

RESULTS

No HPV DNA was detected in groups 1 and 2 which consisted of 3 and 13 specimens respectively. Seven of 11 (63.6%) specimens in group 3 and 7 of 32 (21.9%) in group 4 were found to be positive for in situ HPV DNA. Seven positive samples in group 3 and one positive sample in group 4 were typed as HPV 6/11. Five samples of the remaining positives in group 4 were typed as HPV 16/18. One case was found to be positive with both 16/18 and 31/33.

CONCLUSION

Nonradioactive DNA in situ hybridization is an easy and efficient method to be performed for the diagnosis of HPV infections. Koilocytosis with atypy is directly correlated with HPV infection and it is suggested to monitor the CIN cases with HPV type 16/18 infection since the pathology can be progressive.

Serological and nucleic acid analyses for HIV and HTLV infection on archival human plasma samples from Zaire

In order to better understand the genomic diversity and molecular phylogeny of the human retroviruses, the plasmas from 250 Zairean patients collected in 1969 were tested for antibodies to human T-cell lymphoma and human immunodeficiency viruses (HTLV or HIV) using ELISA and confirmatory Western blots and for viral nucleic acids by reverse transcriptase-directed PCR (RT-PCR). Interestingly, none of the patients was confirmed positive for HIV, even though this region is now endemic for HIV-1. However, 74 (30%) and 3 (1%) of the samples were positive for antibodies to HTLV-I and II, respectively. Forty-four of 74 (59%) Western blot-positive Zairean samples were RT-PCR positive for HTLV-I, while 1 of 3 (33%) of HTLV-II-seropositive samples was RT-PCR positive. On the contrary, none of the Western blot-negative or indeterminate samples were RT-PCR positive for either HTLV-I or HTLV-II. We have cloned and sequenced 140 bp of the pol gene flanked by SK110/SK111 from 8 HTLV-I- and 1 HTLV-II-positive archival samples from Zaire. The HTLV-I isolates from Zaire cluster together as a phylogenetic group, diverging from the prototype Japanese HTLV-I (ATK) by a range of 1.4 to 3.6%. Their close homology to some African STLV-I isolates suggests relatively recent interspecies transmission. The Zairean HTLV-II isolate is closely grouped with the HTLV-II substrain of isolates found in Paleo-Amerindians of the New World, making it unlikely that it represents an endemic African strain.