Detection of varicella-zoster virus DNA by nested PCR in CSF from HIV-infected patients: A prospective evaluation

The aim of this prospective study was to determine the frequency and clinical significance of detection of varicella-zoster virus (VZV) DNA in cerebrospinal fluid (CSF) from 120 HIV-infected individuals. Six of 8 CSF samples from patients with recent (up to 8 months previously) or concurrent cutaneous zoster contained detectable VZV DNA using the polymerase chain reaction. No detectable CSF VZV DNA was present in two patients who had an encephalopathy complicating cutaneous zoster or in 112 other patients without a history of recent of concurrent zoster. In conclusion, VZV DNA may be detected in CSF of patients with neurological disease and concurrent or recent zoster. However, the absence of detectable VZV DNA in CSF does not preclude the possibility of VZV associated neurological complications.

Development and evaluation of an internally controlled semiautomated PCR assay for quantification of cell-free cytomegalovirus

Quantification of circulating human cytomegalovirus (HCMV) is useful in clinical contexts such as virological surveillance of bone marrow transplant recipients and monitoring of antiviral therapy. This report describes an internally controlled, quantitative, semiautomated, HCMV genome assay that was developed primarily to measure HCMV DNA in the plasma of severely leucopaenic patients. It exhibits greater sensitivity, wider dynamic range and higher sample throughput than a number of previously described commercial and "in-house" assays. Viral DNA extraction from EDTA plasma samples was automated using a BioRobot 9604 (Qiagen). HCMV strain AD169 was used to prepare a calibration curve and murine cytomegalovirus (MCMV) strain Smith was added as internal control to all calibration standards and test samples. Amplification was performed using a set of primers based on the HCMV UL50 region, capable of amplifying both human and murine CMV. The yield of biotinylated polymerase chain reaction (PCR) products was estimated using HCMV-specific and MCMV-specific enzyme-labelled probes and automated chemiluminescence detection. Log-transformed HCMV-to-MCMV signal ratios were calculated and used for quantification of test samples against simultaneously extracted MCMV-spiked calibration standards. Evaluation of the assay sensitivity by Probit analysis demonstrated a 95% probability of detection at 100 HCMV genomes per ml of plasma; the dynamic range was shown to be > or = 4 log(10). A total of 315 samples from 61 bone marrow transplant patients were analysed by both the quantitative PCR (qPCR) and by a previously validated nested nonquantitative PCR (NQPCR). A high level of concordance (90%) was observed between the two assays, although the qPCR assay exhibited slightly greater sensitivity.

Evaluation of diagnostic methods for the detection of cytomegalovirus in recipients of allogeneic stem cell transplants

BACKGROUND

Although several diagnostic methods are available for the surveillance of patients at risk of human cytomegalovirus (CMV) infection and disease, little data is available on their comparative performances in the diagnostic setting.

OBJECTIVES

To compare different assays for CMV detection, especially assays based on (quantitative) DNA and mRNA detection.

STUDY DESIGN

Eight allogeneic bone marrow and stem cell transplant recipients at high risk for developing CMV disease (donor CMV-negative, recipient positive) were regularly tested for 7-20 weeks post-transplant by spin-amplification rapid culture from urine (viruria), antigenemia (pp65 assay), pp67 mRNA in whole blood (NASBA), and CMV DNA both qualitatively (in-house PCR, whole blood) and quantitatively (in-house PCR, plasma; Cobas Amplicor CMV Monitor Test, plasma and whole blood; Hybrid Capture, whole blood).

RESULTS

Four patients (50%) suffered CMV reactivation during follow-up. Out of 104 sample dates, 41 (39.4%) yielded a positive CMV result in at least one assay. Out of the 28 samples tested by all assays, the highest percentage of positive results was obtained with the in-house quantitative PCR (60.7%), followed by the Hybrid Capture system (39.3%), the Cobas Amplicor CMV Monitor Test, plasma version (35.7%), the Cobas Amplicor CMV Monitor Test, whole blood version (32.1%), in-house qualitative PCR (28.6%), and the mRNA assay (21.4%). Viruria was positive in one sample and pp65 antigenemia was found in two samples.

CONCLUSIONS

Despite a considerable incidence of CMV reactivations, pre-emptive anti-CMV chemotherapy prevented the development of CMV disease with the exception of one case. The molecular assays had superior sensitivity to conventional ones. The antigenemia assay proved unsuitable for the surveillance of hematological transplant patients. However, none of the tests recognized all timepoints with CMV reactivation. Further comparative studies are needed to determine their respective diagnostic values.

Extended routine polymerase chain reaction surveillance and pre-emptive antiviral therapy for cytomegalovirus after allogeneic transplantation

Pre-emptive treatment strategies based on sensitive screening for cytomegalovirus (CMV) infection up to day +100 after allogeneic transplantation have been shown to reduce the incidence of CMV disease during the period of surveillance. However, the use of ganciclovir has been associated with delays in immune reconstitution and an increased incidence of late CMV disease after day +100. In the present study, 81 patients undergoing allogeneic transplantation received polymerase chain reaction (PCR)-guided pre-emptive therapy based on detection of CMV DNA by PCR on 2 consecutive weeks up to day +180. Thirty-three of the 52 high-risk patients (CMV-seropositive donor or recipient) received a total of 45 treatment episodes up to day +100. Three of these patients (5.7%) developed CMV disease, with one fatality. Twelve of the surviving 44 high-risk patients (27%) required pre-emptive treatment between days +101 and +192, but none of these patients developed late CMV disease with a median follow-up of 402 d (range 117-952 d). Antiviral therapy was stopped after a single negative PCR result with no subsequent episodes of CMV disease while patients remained off antiviral treatment. As all initial episodes of CMV DNA detection occurred within 60 d of transplantation, it may be possible to discontinue monitoring beyond day +100 in patients who have remained CMV PCR negative before this. Thus, we have confirmed that PCR-guided pre-emptive therapy results in a low incidence of CMV disease before day +100 and that discontinuing treatment on the basis of viral clearance as determined by CMV PCR appears to be safe practice. In addition, we have observed no episodes of late CMV disease with an extension of surveillance to 26 weeks.

No apparent effect of cidofovir in epidermodysplasia verruciformis

This paper reports the failure of a patient suffering from Epidermodysplasia verruciformis, characterised by widespread infection of the skin with human papillomaviruses, to respond to topical and systemic treatment with the antiviral agent, Cidofovir, despite its previously demonstrated effectiveness against a range of different papillomavirus-associated conditions.

False-negative HIV antibody test results

Ideally HIV antibody tests have to be both extremely sensitive and able to recognize all known HIV subtypes. Three patients whose sera failed to react with a synthetic oligopeptide-based HIV antibody test are described in this report. The patients were a Pakistani male infected recently, an Australian male infected for several years, and a Ugandan woman with AIDS. The presence of anti-HIV antibodies was confirmed by means of a standard algorithm with different assay formats. All three sera failed to react in one antiglobulin enzyme-linked immunosorbent assay (ELISA) (Bioelisa HIV-1+2, Biokit SA). No single underlying reason could be identified for the assay failure in the three cases. The first patient, probably infected recently when first tested, was strongly positive by the same assay a year later, confirming the relative insensitivity of oligopeptide assays reported previously for detecting the early antibody response. The other two patients appear to have been infected for several years. Although unlikely to have been infected with a non-clade B virus, the sample from patient 2 lacked detectable antibody to the transmembrane glycoprotein (gp41), the site of the synthetic oligopeptides. Patient 3, of Ugandan origin, was found to be infected with a non-clade B virus. Although her serum reacted strongly to subtype B gp41 in Western blot, it failed to react in the antiglobulin ELISA. Since there appears to be no single common explanation for these three failures there is little opportunity to identify prospectively those situations where testing using assays employing synthetic oligopeptides on the solid phase is likely to fail.

Magnetic resonance imaging, thallium-201 SPET scanning, and laboratory analyses for discrimination of cerebral lymphoma and toxoplasmosis in AIDS

OBJECTIVES

To compare the results of magnetic resonance imaging (MRI) and thallium-201 (201Tl) SPET scanning with laboratory analyses including CSF DNA detection, brain biopsy, and necropsy in the discrimination of cerebral lymphoma and toxoplasmosis in patients with AIDS.

METHODS

A retrospective study of 32 patients infected with HIV who had focal CNS lesions on MRI as a result of either lymphoma or toxoplasmosis.

RESULTS

18 patients had lymphoma, 12 had toxoplasmosis, and two had both. Toxoplasma IgG antibodies were detected in only seven patients--four with toxoplasmosis, two with lymphoma, and one with both diagnoses. Epstein-Barr virus DNA was detected in CSF of all six patients with lymphoma and none of two with toxoplasmosis. MRI showed multiple lesions in 23 patients, appearances did not discriminate between lymphoma and toxoplasmosis; nine patients had single lesions, of these eight had lymphoma (p = 0.044, two tailed Fisher's exact test) 201Tl SPET showed accumulation in 17 with lymphoma and six with toxoplasmosis (p = 0.034, two tailed Fisher's exact test). Of nine patients with single lesions on MRI and 201Tl SPET with focal accumulation eight had lymphoma. 201Tl SPET uptake ratios of > or = 2.9 were only seen with lymphoma.

CONCLUSION

Knowledge of patients' toxoplasma serostatus does not aid discrimination between lymphoma and toxoplasmosis. Single lesions on MRI with focal accumulation of 201Tl strongly suggest lymphoma. Multiple lesions on MRI with 201Tl SPET uptake ratios > or = 2.9 also suggest lymphoma; uptake ratios less than 2.1 do not aid discrimination. Detection of Epstein-Barr virus DNA in CSF is highly sensitive and specific for cerebral lymphoma.

Detection of Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus DNA in CSF from persons infected with HIV who had neurological disease

OBJECTIVES

To determine the frequency and clinical relevance of Epstein-Barr virus (EBV) and Kaposi's sarcoma associated herpesvirus (KSHV) DNA detection in the CSF from patients infected with HIV.

METHODS

Cerebrospinal fluid was obtained prospectively from 115 consecutive patients infected with HIV undergoing diagnostic lumbar puncture for investigation of neurological disease. Amplification of DNA was performed using a nested polymerase chain reaction (PCR) for detection of EBV internal repeat and KSHV minor capsid sequences.

RESULTS

EBV DNA was detected in the CSF supernatant of 18 patients. This included all patients with primary CNS lymphoma (seven patients) or a combination of systemic and CNS lymphoma (two patients). By contrast EBV DNA was not detected in the CSF supernatant of any patient with systemic, but not CNS, lymphoma (10 patients). EBV DNA was also detected in the supernatant of nine further patients without a diagnosis of lymphoma at the time of lumbar puncture, two of whom subsequently developed CNS lymphoma. No EBV DNA was detected in CSF supernatant from the remaining 87 samples (two of these patients subsequently developed lymphoma). KSHV DNA was detected in the CSF of two patients, one had systemic (but not CNS) lymphoma and the other did not have lymphoma.

CONCLUSION

A diagnosis of CNS lymphoma is strongly associated with the presence of EBV DNA in CSF. In the absence of clinical and radiological features of CNS lymphoma, the presence of detectable CSF EBV DNA may predict subsequent tumour development. KSHV DNA is rarely detected in CSF in this patient group and shows no correlation with lymphoma or other neurological disease.

Management of intracerebral lesions in patients with HIV: a retrospective study with discussion of diagnostic problems

A total of 95 patients who presented in 1994 and 1995 with focal brain lesions at a London HIV centre were studied retrospectively. Patients were allocated to "definite" or "presumed" diagnostic categories of toxoplasma encephalitis (TE), primary CNS lymphoma (PCNSL) or progressive multifocal leukoencephalopathy (PML), based on strict criteria. The number in each category was: TE, 20; PCNSL, 9; PML, 7; presumed TE, 12; presumed PCNSL, 8 and presumed PML, 17. There were 20 patients in whom a diagnosis could not be made, and there were three non-HIV diagnoses. Demographic data, features at presentation and routine CSF analysis were not discriminatory in making a diagnosis. Toxoplasma titres were a median of 1:256 in those with TE compared to 1:16 in all other groups (p < 0.001) and those with TE were less likely to be on toxoplasma prophylaxis compared to those with PCNSL (p < 0.002). Survival with TE (median of 446 days) was significantly longer than survival in all other groups. Survival with either confirmed or presumed PML was similar. The problems of diagnosis of focal brain lesions in HIV patients are discussed and a management flow chart for mass lesions is proposed.

Association of Kaposi's sarcoma associated herpesvirus (KSHV) DNA in bronchoalveolar lavage fluid of HIV infected individuals with bronchoscopically diagnosed tracheobronchial Kaposi's sarcoma

OBJECTIVES

To determine the frequency of detection of Kaposi's sarcoma associated herpesvirus (KSHV), also known as human herpesvirus (HHV) type 8, DNA in bronchoalveolar lavage (BAL) fluid from HIV infected individuals with and without KS and to compare this with the detection rate in peripheral blood. Also to identify whether KSHV was associated with specific cell types in lavage fluid.

METHODS

Nested PCR was used to detect KSHV DNA in BAL fluid from 41 consecutive individuals with Kaposi's sarcoma (KS) and in 41 controls with similar CD4 lymphocyte counts. Semiquantification of viral DNA was by end point titration. A positive cell sorting selection procedure was used to isolate specific BAL fluid cell types.

RESULTS

KSHV DNA was detected in BAL fluid from 24 of 29 (83%) individuals with a bronchoscopic diagnosis of tracheobronchial KS. None was detected in 12 individuals with only cutaneous KS, or in 41 matched controls without KS. In five, KSHV DNA was detected in the cell depleted and cellular fractions of BAL fluid and in 1/5 in the CD14 (macrophage) fractions. None was detected in the CD19 (B lymphocyte) or CD4/CD8 (T lymphocyte) fractions.

CONCLUSIONS

There was a clear association between the diagnosis of tracheobronchial KS and detection of KSHV DNA in BAL fluid. The cell type supporting KSHV in the respiratory tract is not CD 19 positive and has yet to be conclusively identified.

Necrotising herpetic retinopathy in patients with advance HIV disease

OBJECTIVES

To describe the presenting features, clinical and laboratory diagnosis, response to treatment, and outcome of necrotising herpetic retinopathy (NHR) in HIV infected patients.

METHODS

Retrospective case records/laboratory data review of five HIV infected patients presenting to the specialist HIV/AIDS unit at UCL Hospitals, London from April 1994 to August 1996 with a clinical diagnosis of NHR.

RESULTS

All patients had advanced HIV disease with a median CD4 count of 20.10(6)/1. Three patients had cutaneous varicella zoster virus (VZV) infection within the preceding 8 weeks. All had uniocular loss of visual acuity; one also had headache and another ocular pain. All had typical retinal appearances. VZV DNA was detected in cerebrospinal fluid of four patients (and in vitreous fluid of one of the four) and in vitreous fluid of one other. One patient refused therapy and rapidly became blind. Four patients received intravenous foscarnet with intravenous aciclovir for 6 weeks: three subsequently received oral famciclovir and one oral valaciclovir; two patients also had intravitreal injections of foscarnet. In none of the four did treatment bring about improvement in visual acuity, but in all four visual loss from retinitis was halted.

CONCLUSIONS

NHR occurs in HIV infected patients with advanced HIV disease and is strongly associated with evidence of VZV infection. With aggressive use of antiviral drugs the outcome is not uniformly poor.

Cerebrospinal fluid ferritin in HIV infected patients with acute neurological episodes

OBJECTIVES

To measure cerebrospinal fluid (CSF) ferritin in HIV infected patients with acute neurological episodes and to correlate the findings with the type and severity of neurological disease.

METHODS

CSF ferritin and the ratio of CSF to serum albumin (QAlb) were prospectively measured in 27 consecutive HIV infected patients admitted to a specialist unit for investigation of acute neurological episodes; the results were compared with their clinical diagnoses.

RESULTS

Ten patients had HIV associated dementia complex, six had cryptococcal meningitis, two had primary CNS lymphoma and nine had miscellaneous conditions including herpes simplex virus encephalitis, cytomegalovirus encephalitis, cerebral toxoplasmosis and mononeuritis multiplex. Overall, 16 (59%) patients had raised CSF ferritin levels, ranging from 13.0 to 50.2 micrograms/l, (median = 16.1 micrograms/l: normal range = 1.0-12.0 micrograms/l). Thirteen of the 16 also had normal QAlb values, implying an intact CSF-blood barrier, and thus that local synthesis of ferritin had occurred. Elevated ferritin levels were not associated with particular neurological diagnoses. In those with HIV associated dementia complex there was no correlation between CSF ferritin levels and the severity of clinical cognitive deficit or the extent of magnetic resonance imaging abnormalities.

CONCLUSIONS

An elevated CSF ferritin level is a non-specific finding in HIV infected patients presenting with acute neurological episodes.

Comparison of magnetic resonance imaging with neuropathological findings in the diagnosis of HIV and CMV associated CNS disease in AIDS

OBJECTIVES

To compare the results of clinical assessment and MRI with neuropathological findings in the diagnosis of HIV and cytomegalovirus (CMV) associated CNS disease.

METHODS

A retrospective study of 35 patients infected with HIV who were examined at necropsy between four and 70 (median 20) days after neurological assessment and MRI.

RESULTS

Of the 35 patients, 19 had diffuse white matter hyperintensity on T2 weighted MRI, six of whom also had focal lesions. Nine other patients had focal white matter lesions and seven had changes in cortical atrophy only. Necropsy in the 19 with diffuse white matter hyperintensity showed HIV leukoencephalopathy (HIVLEP) with encephalitis in 10, CMV encephalitis in three, both HIVLEP/HIV encephalitis and CMV encephalitis in one, lymphoma in three, and non-specific inflammation in two. Necropsy in the 16 other patients without diffuse white matter hyperintensity showed CMV encephalitis in six, HIV encephalitis (without HIVLEP) in two, CMV encephalitis and HIVLEP/HIV encephalitis in one, non-HIV associated abnormalities in five, herpes simplex encephalitis in one, and lymphoma in one. CMV DNA was detected in CSF of five of seven patients with CMV encephalitis and in two of two with CMV associated polyradiculopathy but without CMV encephalitis. Diffuse white matter hyperintensity on MRI had a sensitivity of 100%, a specificity of 66.6%, and a positive predictive value of 58% for diagnosis of HIVLEP.

CONCLUSION

Diffuse white matter hyperintensity on MRI can be due to either HIV or CMV associated pathology or non-specific abnormalities.

Acute lumbosacral polyradiculopathy due to cytomegalovirus in advanced HIV disease: CSF findings in 17 patients

OBJECTIVES

To describe the abnormalities in CSF from HIV infected patients with acute lumbosacral polyradiculopathy (ALP) caused by cytomegalovirus (CMV) infection.

METHODS

Retrospective case notes and laboratory records were reviewed for 17 consecutive patients with CMV associated ALP admitted to specialist HIV/AIDS units at UCL Hospitals and Chelsea and Westminster Hospital.

RESULTS

Infection with CMV was confirmed by detection of CMV DNA by polymerase chain reaction amplification in 15 patients (all of whom were negative by culture), by culture in one patient, and by objective clinical response to anti-CMV treatment in one patient. Only nine patients had a CSF pleocytosis 28-1142 (median 150) cells/mm3; in seven there was a polymorphonuclear (PMN) leucocyte preponderance. Protein concentrations in CSF were moderately or considerably raised in 13 patients; CSF: plasma glucose ratios were < or = 50% in five patients. Two patients had no pleocytosis, normal CSF: plasma glucose, and normal or near normal protein values.

CONCLUSIONS

Abnormalities in CSF in CMV associated ALP are varied: only 50% of patients have a "typical" PMN preponderant pleocytosis. The diagnosis of this condition should not rely on demonstration of a PMN preponderant pleocytosis, but on identification of CMV DNA in CSF and the exclusion of other opportunistic infections and lymphoma in order that specific anti-CMV treatment may be instituted.

Regression of AIDS-related Kaposi's sarcoma during therapy with thalidomide

A 14-year-old girl with HIV infection and subcutaneous Kaposi's sarcoma (KS) received thalidomide therapy for oral ulcers, resulting in regression of KS lesions, disappearance of KS-associated herpesvirus (KSHV) DNA from blood, and reduced viral load in tumor tissue. Administration of grauntocyte colony-stimulating factor resulted in clinical exacerbation of KS and reappearance of KSHV DNA in blood.

Hepatitis B nucleotide sequence analysis: linking an outbreak of acute hepatitis B to contamination of a cryopreservation tank

An epidemiological investigation indicated that six patients treated in a haematology unit who developed acute hepatitis B may have been infected as a result of contamination of a liquid nitrogen bone marrow storage tank. The clinical details are described elsewhere (Tedder et al., 1995); we describe the virological methods used to support the findings. HBV DNA was amplified from sera using a nested PCR with primers for the surface gene, and a region encompassing precore, the 3' end of X, and the 5' end of core. HBV DNA was also extracted from the frozen detritus in the liquid nitrogen storage tank. After equilibration, the aqueous material was filtered, co-precipitated with albumin and polyethylene glycol and the HBV DNA extracted by phenol-chloroform and ethanol precipitation. Direct nucleotide sequence analysis indicated that four patients were infected with HBsAg subtype adw viruses which carried novel amino acid substitutions at codons 145 and 146 of the X gene. HBV DNA extracted from the storage tank detritus contained identical sequences. The samples from two other patients, subtype ayw, did not contain the novel sequence changes in X and had other sequence differences. These findings linked conclusively the four patients as a cluster and the rescue of HBV-DNA sequences from the contaminated storage tank by the method described confirmed this as the common source of infection. Two other HBsAg-positive patients were excluded from the cluster by sequence analysis. Demonstration of infection by this route has implications for the safe storage of bone marrow and other related biological materials.

Detection of polyomaviral DNA in clinical samples from immunocompromised patients: correlation with clinical disease

Clinical samples from immunocompromised patients were screened for polyomaviral sequences by nested polymerase chain reaction (PCR) to evaluate the association of these viral infections with progressive multifocal leukoencephalopathy (PML). JC virus (JCV) DNA was detected in 19 of 23 CSF samples and all four brain samples from patients with PML. Neither BK virus (BKV) nor simian virus 40 (SV40) DNA were detected in these samples. No evidence was found to support the hypothesis that polyomaviral DNA is present in the central nervous system of immunosuppressed patients without PML (CSF n = 67, brain n = 19). JCV DNA was not detected in any peripheral blood sample included in this study. JCV DNA was detected in urine from three of eight patients with PML, but was also amplified from three of 29 urine samples from patients without PML, JCV, and not SV40 or BKV, was associated with PML in this study.

Community-based respiratory viral infections in HIV positive patients with lower respiratory tract disease: a prospective bronchoscopic study

OBJECTIVES

To evaluate the contribution of community-based respiratory virus infections to lower respiratory tract disease in HIV-1 infected individuals.

DESIGN

Prospective clinical cohort study.

SETTING

Specialist in-patient unit for HIV and AIDS, University College London Hospitals, London.

SUBJECTS

44 consecutive HIV-1 antibody positive patients who underwent 47 diagnostic bronchoscopies for evaluation of the symptoms and signs of lower respiratory tract disease. TIME: Winter months of 1994/95.

MAIN OUTCOME MEASURES

Detection, in bronchoscopic alveolar lavage fluid, of infection with influenza A and B, respiratory syncytial virus (RSV), parainfluenza 1, 2 and 3 (by immunofluorescence and cell culture) and adenovirus and enteroviruses (by cell culture).

RESULTS

No evidence of influenza, RSV, parainfluenza, adenovirus, or enterovirus infection was detected.

CONCLUSIONS

Despite a marked increase in RSV and influenza B infection in the general population over the winter of 1994-95, respiratory virus infections were not detected in this cohort of HIV infected patients. As the organisms causing lower respiratory tract disease were related to immunosuppression, this study questions the value of routine identification of community-based respiratory viruses in this patient group.

Detection of herpesvirus DNA by nested polymerase chain reaction in cerebrospinal fluid of human immunodeficiency virus-infected persons with neurologic disease: a prospective evaluation

A nested polymerase chain reaction-based method was used prospectively to detect herpesvirus DNA in cerebrospinal fluid (CSF) from 111 patients with AIDS, 39 of whom had a suspected diagnosis of cytomegalovirus (CMV)-associated neurologic disease (patients with encephalopathy, polyradiculopathy, or peripheral neuropathy) and 72 who had alternative diagnoses. CSF from 24 (62%) of the patients with suspected CMV-associated disease had detectable CMV DNA compared with only 8 (11%) of the patients with other diagnoses. Varicella-zoster virus DNA was detected in CSF from 3 patients (2 with myelitis and 1 with encephalitis), all of whom had recent cutaneous zoster. No CSF specimen contained detectable herpes simplex virus type 1 DNA, and none of the patients with myelitis had detectable herpes simplex virus type 2 DNA in CSF. This study demonstrates a significant association between detectable CMV DNA in CSF and suspected CMV-associated neurologic disease in patients with AIDS.

Detection of Kaposi sarcoma associated herpesvirus in peripheral blood of HIV-infected individuals and progression to Kaposi's sarcoma

Kaposi sarcoma-associated herpesvirus (KSHV) is consistently found in biopsy samples from patients with AIDS-related and "classical" Kaposi's sarcoma (KS). Although highly suggestive of a causal role of KSHV in the pathogenesis of KS, this observation does not exclude the possibility that KSHV, like other herpesviruses, is widely distributed and is a mere "passenger" in these lesions. Here we report that KSHV was detectable in peripheral blood mononuclear cells of 24/46 (52%) of KS patients, but in none of 134 blood donors or 26 HIV-uninfected hospital controls. KSHV detection increased with immunosuppression, as shown by a correlation with a reduced number of CD4-positive T-cells. Moreover, KSHV detection in peripheral blood cells of HIV-infected individuals without KS predicted the subsequent appearance of KS lesions. 143 patients who did not have KS at the time of their first (or only) blood sample were followed up for a median of 30 months. Of the 11 who had been KSHV positive 6 developed KS compared with only 12 out of 132 who were KSHV negative. These findings are compatible with a causative role of KSHV in KS. KSHV was rarely detected in sputum and throat swabs of HIV-infected patients, providing a potential explanation for the apparently limited spread of this virus.

Herpes simplex virus type 2 encephalitis and concomitant cytomegalovirus infection in a patient with AIDS: detection of virus-specific DNA in CSF by nested polymerase chain reaction

A Caucasian homosexual man with AIDS and cytomegalovirus retinitis presented with facial pain and episodic confusion, had several seizures and became obtunded. An electroencephalogram was suggestive of herpes simplex encephalitis. The diagnosis was confirmed by detection of herpes simplex virus type 2 (HSV 2), but not type 1, DNA in cell-free cerebrospinal fluid (CSF) after amplification by nested polymerase chain reaction. The patient also had evidence of concomitant cytomegalovirus (CMV) infection with detectable CMV DNA in CSF. With high-dose acyclovir the patient recovered. Analysis of a follow up CSF sample taken four months later showed no detectable HSV-2 DNA.

Typing of human papillomaviruses in cervical carcinoma biopsies from Cape Town

Sixty-eight cervical carcinoma biopsies from women at Groote Schuur hospital in Cape Town were screened for human papillomavirus (HPV) DNA by polymerase chain reaction (PCR) amplification with subsequent typing by hybridisation with specific oligonucleotides. Amplified DNAs which hybridised with the HPV group-specific oligonucleotide probes, but with none of the type-specific probes, were categorized as unclassified HPV types. Eighty-one percent of samples were HPV positive and the following distribution and types were detected: 46% HPV 16, 1.5% HPV 18, 6% HPV 31, 6% HPV 33, 1.5% HPV 45, and 25% unclassified HPVs. Four of the tumours had detectable dual infections with the following combinations of HPVs: HPV31/HPV33; HPV16/HPV33; HPV18/HPV16; HPV45/HPV33. Tumour DNA from the 17 PCR unclassified HPVs was analysed by Southern blotting and gave the following results: 11 were negative, 4 were positive on hybridisation but could not be typed (unclassified HPV), 1 was HPV 16, and 1 resembled the HPV 16 "variant" described previously [Williamson et al. (1989): Journal of Medical Virology 28:146-149]. Only 2 of 13 samples that were negative for HPV by PCR were positive for unclassified HPVs by Southern blot analysis. Sequencing of a PCR product revealed that one of the unclassified HPVs was HPV 52. This is the first record of HPV 52 and HPV 45 in Africa.

Hepatitis C virus infection in haemodialysis patients: a clinical and virological study

A cohort of 66 patients on maintenance haemodialysis was examined for serological (anti-HCV) and virological (HCV-RNA) evidence of infection with hepatitis C virus (HCV). Nine (13.6%) were anti-HCV positive, all of whom had detectable HCV-RNA in their serum. Statistical analysis of various risk factors (including length of time on haemodialysis, history of blood transfusion, history of renal transplantation and of previous hepatitis B infection) showed that only the length of time on haemodialysis was significantly associated with the acquisition of HCV infection. Genotypic analysis showed that five patients were infected with genotype 1 and a further two were infected with genotype 4. The latter finding is of significance because strains of genotype 4 are extremely uncommon in Western Europe. These results demonstrate that intra-unit transmission of HCV-infection took place in a group of patients on maintenance haemodialysis.

Detection of varicella-zoster virus DNA using the polymerase chain reaction in an immunocompromised patient with transverse myelitis secondary to herpes zoster

A case of herpes zoster transverse myelitis is described in which the clinical diagnosis was confirmed by demonstrating the presence of varicella-zoster virus (VZV) DNA in the cerebrospinal fluid (CSF) by amplification using the polymerase chain reaction. This case illustrates the potential role of the selective amplification of VZV DNA from CSF in contributing to the diagnosis of neurological complications associated with VZV infection.

Acute hepatitis C infection in patients undergoing therapy for haematological malignancies: a clinical and virological study

Patients receiving multiple transfusions are at risk of acquiring hepatitis C (HCV) infection from a donor population which is unscreened for hepatitis C antibodies (anti-HCV). Prior to the introduction of blood donor screening for anti-HCV in the U.K., a group of patients undergoing therapy for haematological malignancies, with repeatedly abnormal liver function tests, were investigated for acute HCV infection. Thirty-two patients had repeatedly raised serum transaminases, and eight of these (25%) had evidence of an acute HCV infection. The diagnosis was made by the detection of HCV-RNA in the patients' serum using a complementary DNA/polymerase chain reaction (cDNA/PCR) procedure. All eight patients had received myeloablative chemotherapy and three had undergone bone marrow transplantation. HCV infection contributed significantly to the morbidity of this group of patients in the short term whilst they were undergoing treatment for their underlying haematological condition. The long-term effects have yet to be evaluated. In an attempt to decrease hepatic damage due to HCV, three patients were placed on interferon therapy. None showed a sustained reduction in serum transaminases or HCV viraemia. It is hoped that the introduction of anti-HCV screening of blood donors, will reduce the frequency of transfusion-acquired HCV infections. Early observations suggest that this is the case, as we have seen no new cases of HCV infection in our unit since the introduction of donor screening in September 1991.

High prevalence of hepatitis C virus antibodies in a local haemophiliac population

Non-A, non-B hepatitis is common among individuals with clotting factor deficiencies who have had multiple exposures to replacement concentrate. Newly introduced screening tests for hepatitis C virus antibody make it possible to determine the prevalence of this entity in defined populations. In 68 haemophiliac patients attending the Groote Schuur Hospital clinic, 44 were shown to be positive (65%). There was no significant correlation between seropositivity for this agent and severity of the bleeding disorder, age or elevation of the liver enzyme values.

Hepatitis C virus antibodies in patients with liver disease. The western Cape experience

Hepatitis C virus (HCV) is a recently characterised non-A, non-B hepatitis (NANBH) agent, which appears to be important in both parenteral and sporadic NANBH. HCV infection has been associated with the development of chronic liver disease, cirrhosis and hepatoma. Groups of patients in the western Cape with chronic liver disease and hepatoma were screened for antibodies to HCV and the results were confirmed by standard neutralisation tests. Three of 19 patients with cirrhosis secondary to alcohol abuse or classic auto-immune chronic active hepatitis were considered to have antibodies to HCV at initial screening. All of these were false-positive results. Five of 20 patients with presumptive chronic NANBH were considered possibly to have antibodies to HCV. Only 1 patient with post-transfusional NANBH was confirmed to have specific HCV antibodies. Two of 30 patients with hepatoma had specific anti-HCV antibodies in contrast to 11 others with serum HBsAg positivity. One hundred blood transfusion donors and 25 antenatal patients were tested concurrently and shown to be negative for anti-HCV. Specific antibodies to HCV were present in very few patients with cirrhosis, presumptive NANBH and hepatoma tested in this local survey. False-positive reactions appeared to occur at a higher rate than true-positive results.

Intradermal vaccination against hepatitis B in a group of medical students

A prospective study of a low-dose (one-tenth) intradermal regimen using recombinant hepatitis B vaccine was undertaken during two consecutive years in 4th-year medical students. Eighty-one per cent of the vaccinees (123/152) sero-converted with anti-HBs levels of greater than 10 IU/l. The lower titre of hepatitis B surface antibodies compared with published studies on intramuscular immunisation, together with a sero-conversion rate of only 81%, makes the intradermal method, in our opinion, a suboptimal form of hepatitis B immunisation.