Sensitivity and specificity of diagnostic tests for genital infection with herpesvirus hominis

Diagnostic Methods and Management Strategies of Herpes Simplex and Herpes Zoster Infections

Herpesviruses are medium-sized double-stranded DNA viruses. Of more than 80 herpesviruses identified, only 9 human herpesviruses have been found to cause infection in humans. These include herpes simplex viruses 1 and 2 (HSV-1 and HSV-2), varicella-zoster virus (VZV), human cyto-megalovirus (HCMV), Epstein-Barr virus (EBV), and human herpesvirus (HHV-6A, HHV-6B, HHV-7, HHV-8). HSV-1, HSV-2, and VZV can be problematic given their characteristic neurotropism which is the ability to invade via fusion of its plasma membrane and reside within neural tissue. HSV and VZV primarily infect mucocutaneous surfaces and remain latent in the dorsal root ganglia for a host's entire life. Reactivation causes either asymptomatic shedding of virus or clinical manifestation of vesicular lesions. The clinical presentation is influenced by the portal of entry, the immune status of the host, and whether the infection is primary or recurrent. Affecting 60% to 95% of adults, herpesvirus-associated infections include gingivostomatitis, orofacial and genital herpes,and primary varicella and herpes zoster. Symptomatology, treatment, and potential complications vary based on primary and recurrent infections as well as the patient's immune status.

Diagnostic methods and management strategies of herpes simplex and herpes zoster infections

Herpes infections are extremely prevalent in the adult population. Recognizing early signs and symptoms is essential to provide effective treatment. The immunocompromised population presents treatment challenges requiring prolonged antiviral therapy and more frequent recurrences. Viral culture is often considered the gold standard diagnostic technique; however, polymerase chain reaction (PCR) should be done in tandem with culture especially for varicella zoster virus infections. Antivirals can decrease viral shedding, recurrences of herpes simplex, and hasten healing of herpes zoster. Herpes virus can be a challenging entity to treat with significant morbidity (both physically and psychologically).

Accuracy of herpes simplex virus detection in liquid-based (SurePath) Papanicolaou tests: a comparison with polymerase chain reaction

A review of our institution's Papanicolaou test records over an 11-yr period showed that liquid-based Papanicolaou tests (LBPTs) had a significantly higher frequency of diagnoses of Herpes simplex virus (HSV)-related cellular changes compared to conventional Papanicolaou smears (77/302,841, 0.026% vs. 56/376,173, 0.015%, P = 0.002). To investigate the accuracy of the diagnosis of HSV by LBPT, we performed conventional polymerase chain reaction (PCR) on the residual samples from 258 prospectively collected LBPT and real-time PCR using a different primer set on a subset of 40 LBPT. Conventional PCR was positive in 22 of 22 cases diagnosed of HSV, 1 of 2 cases diagnosed as suspicious for HSV, and none of 234 LBPT without a cytologic HSV diagnosis. Real-time PCR was positive in 8 of 8 cases diagnosed as HSV and none of the 32 controls. We conclude that LBPT allows an increased detection of HSV that is highly accurate.

The detection of genital tract infection by Papanicolaou-stained tests

A variety of cytological changes suggestive of genital tract infection may be noted during microscopy of a Papanicolaou-stained cervical smear. The dilemma faced by cytopathologists is whether or not to report suspicious changes to the clinician responsible for the woman's care. This review examines the effectiveness of Papanicolaou-smear microscopy in the diagnosis of the more common sexually transmitted infections, and aims to encourage debate on the reporting of suggestive cytological changes.

Management of the abnormal Papanicolaou smear

Screening for cervical neoplasia has been effective in decreasing invasive cervical cancer. As the understanding of the association of HPV with cervical neoplasia increases, new screening interventions may be developed. Classification of cytologic abnormalities and the management of abnormal smears continue to evolve. Ancillary screening techniques such as HPV typing and cervicography may be useful but need further study.

Genital ulcer disease: accuracy of clinical diagnosis and strategies to improve control in Durban, South Africa

OBJECTIVE

To investigate the accuracy of clinical diagnosis in genital ulcer disease (GUD); to devise management strategies for improving the control of GUD and thereby limit the spread of HIV-1 infection.

DESIGN

Clinical and microbiological assessment of GUD in men and women. The index of suspicion, diagnostic accuracy, diagnostic efficiency and positive and negative predictive values of a clinical diagnosis were investigated.

SETTING

City Health Sexually Transmitted Diseases Clinic, King Edward VIII Hospital, Durban, South Africa.

PARTICIPANTS

100 men and 100 women with genital ulcers.

RESULTS

The accuracy of a clinical diagnosis was, in men: lymphogranuloma venereum (LGV) 66%, donovanosis 63%, chancroid 42%, genital herpes 39%, primary syphilis 32%, mixed infections 8%, and in women; secondary syphilis 94%, donovanosis 83%, genital herpes 60%, primary syphilis 58%, chancroid 57%, LGV 40%, mixed infections 14%. Overall, diagnostic efficiency was greater in women than in men. When compared with other causes of GUD, donovanosis ulcers bled to the touch and were larger and not usually associated with inguinal lymphadenopathy. In women, extensive vulval condylomata lata were readily differentiated from all other causes of GUD.

CONCLUSION

A clinical diagnosis in genital ulceration was less accurate in men than in women. The diagnostic accuracies for donovanosis and secondary syphilis were relatively high but for most other conditions were low. Differences between clinical and laboratory diagnostic accuracies may reflect similarities between the clinical appearances of the various causes of GUD, the presence of mixed infections, atypical ulceration due to longstanding disease, and insensitive laboratory tests. In this community all large ulcers should be treated empirically for syphilis and donovanosis. Uncircumcised men with GUD are an important HIV core or "superspreader" group locally, and prevention strategies should include counselling and health education in the light of the inaccuracy of clinical diagnosis found in this study. The development of rapid accurate tests for GUD is urgently required.

Genital herpes diagnosed by cervical cytology

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The immunoperoxidase method for the rapid diagnosis of intraoral herpes simplex virus infection in patients receiving bone marrow transplants

Bone marrow transplant patients (N = 12) with oral lesions consistent with herpes simplex virus (HSV) infection were studied to compare the sensitivity of two rapid cytodiagnostic methods with viral cultures. Routine viral cultures and exfoliative cytology smears were prepared for microscopic evaluation using the Papanicolaou method and an immunoperoxidase staining technique for detection of HSV type 1. Patients with a positive viral culture (N = 10) showed positive staining for HSV, using the immunoperoxidase technique. Multinucleated giant epithelial cells were observed in only seven of the ten positive specimens, using the Papanicolaou method. The results from this preliminary study suggest that the immunoperoxidase method may provide the dentist with a reliable and rapid approach for the diagnosis of intraoral HSV.

Rapid detection methods in microbiology: are they right for your office?

This article discusses some of the direct test methods for diagnosing Group A streptococcal pharyngitis, urinary tract infection, and the three most common sexually transmitted diseases: gonorrhea, Chlamydia, and Herpes simplex virus infection. Emphasis is placed on their practicality for the office setting as well as the limitations of the test methods in various patient populations.

Clinical approach to urethritis, mucocutaneous lesions, and inguinal lymphadenopathy in homosexual men

The spectrum of sexually transmitted diseases observed among homosexual men is diverse, but in general includes the same infections observed among heterosexuals. A systematic approach to the diagnosis of these diseases, incorporating sexual history, predominant symptoms, findings from physical examination, and office laboratory evaluation will frequently yield a specific diagnosis. Prompt diagnosis and treatment of patients, and when appropriate, of contacts are of critical importance to the prevention of unnecessary morbidity and further transmission of disease.

Comparison of the detection of herpes simplex virus in direct clinical specimens with herpes simplex virus-specific DNA probes and monoclonal antibodies

A comparison of two commercially available kits for rapid herpes simplex virus (HSV) detection directly in patient specimens was performed. The immunofluorescence assay (IFA) utilized monoclonal antibodies to HSV, and the DNA probe assay utilized three HSV sequences cloned into pBR322. A sample of 243 specimens received in viral transport medium were inoculated into MRC-5 tissue cultures. The remainder of the specimen was centrifuged, and the cellular pellet was examined by IFA and DNA probes. One hundred and sixty-two (66.7%) specimens were considered satisfactory for IFA and DNA probe testing, based on a criterion of observing greater than or equal to 2 intact cells per high-power field. Of the 162 specimens, 35 (21.6%) yielded HSV by culture. By IFA, the sensitivity of detecting HSV culture-positive specimens was 77.1%; specificity was 100%, positive predictive value was 100%, and negative predictive value was 93.3%. DNA probe sensitivity was 71.4%; specificity was 90.6%; positive predictive value was 67.6%; and negative predictive value was 92%. Forty-four (27.2%) of the 162 specimens exhibited nonspecific cytoplasmic staining with the DNA probe. IFA and DNA probe assays can be completed in 2 to 3 h, whereas the average time to culture positivity in this series was 2.2 days. Rapid HSV diagnosis can aid in timely and appropriate patient management.

Comparison of ELISA with virus isolation for the diagnosis of genital herpes

An enzyme linked immunosorbent assay (ELISA) system which detects and simultaneously types herpes simplex virus antigens in clinical specimens from patients with genital herpes has been compared with standard tissue culture isolation. Although more sensitive than a similar method previously described and also more sensitive than electron microscopy and immunofluorescence, ELISA did not detect all the viruses isolated in tissue culture. Costs were comparable. The speed of obtaining the result together with knowledge of the type causing infection are useful when antiviral chemotherapy is envisaged and when considering the likelihood of recurrences.

Diagnosis of oral herpes simplex virus infections: practical aspects of viral culture

Viral culture is a valuable aid in the diagnosis of herpes simplex virus infections of the oral cavity, but it is underutilized by members of the dental profession. This article outlines indications for culture, practical aspects of collection and transportation of specimens, reasons for false-negative and false-positive test results, and cost.

Rapid detection of herpes simplex virus in clinical specimens by use of a capture biotin-streptavidin enzyme-linked immunosorbent assay

A sensitive enzyme-linked immunosorbent capture assay with biotin and streptavidin (capture B/SA ELISA) was developed to detect herpes simplex virus (HSV) antigen. Rabbit anti-HSV antibody (immunoglobulin G fraction) was coated on flat-bottom, irradiated, 96-well polystyrene microtiter plates and served to capture HSV antigen. Clinical specimens from patients with genital herpes were added. Biotin-linked rabbit anti-HSV immunoglobulin G was used as the second antibody. The antigen-antibody complex was detected with alkaline phosphatase-conjugated streptavidin, which linked to the biotin. With clinical specimens, the test had a sensitivity of 95.6% and a specificity of 91.4% when compared with the tissue culture method. The presence of HSV antigen in specimens devoid of infectivity was confirmed by blocking the reaction with unlabeled rabbit and human antibody to HSV. The level of antigen detected by the capture B/SA ELISA did not necessarily correlate with the infectivity titer of the specimens. HSV antigens could be detected by the capture B/SA ELISA when the virus infectivity was destroyed at 37 degrees C, by UV irradiation, or by Triton X-100 treatment, but not when hypochlorite treatment was used. Greater sensitivity was obtained when HSV-1- and HSV-2-specific antibody reagents were used simultaneously in each test. The capture B/SA ELISA provides a relatively rapid method (4.5 h) which is quite sensitive and specific when compared with other non-tissue culture, direct assay methods.

Comparison of standard tissue culture, tissue culture plus staining, and direct staining for detection of genital herpes simplex virus infection

Genital herpes simplex virus infection in women was studied by using conventional tissue culture (TC) virus isolation compared with short-term (24-h) TC on Lab-Tek chamber slides followed by fluorescent-antibody (FA) staining. Three different staining techniques were used after TC: (i) staining with biotin-avidin (TC-BA/FA), (ii) direct FA (TC-FA), and (iii) indirect FA. The TC-BA/FA method showed complete correlation with the TC method. The TC-FA method showed no false-positive results but 31.5% false-negative results compared with the TC method. In contrast, the TC-indirect FA method showed 11.9% false-positive results and 11.7% false-negative results. The direct staining of specimens by the biotin-avidin technique (direct BA/FA) without prior tissue culture showed 37.7% false-positive results and 11.1% false-negative results. The TC-BA/FA technique thus was as sensitive as, but more rapid than, the TC method. The quality of fluorescence was far superior in TC-BA/FA staining as compared with TC-FA or TC-indirect FA procedures. The TC-BA/FA appears to be a valuable technique in laboratory diagnosis of genital herpes infections, especially in clinical situations requiring rapid detection of the virus.

Comparison of direct immunofluorescence and direct immunoperoxidase procedures for detection of herpes simplex virus antigen in lesion specimens

Direct immunofluorescence and direct immunoperoxidase staining were equally sensitive and specific for detection of herpes simplex virus antigen in lesion specimens, and each method showed 82% agreement with virus isolation results.

Detection of herpes simplex virus in clinical specimens by DNA hybridization

An assay to detect herpes simplex virus (HSV) DNA in clinical specimens has been developed. It utilizes nucleic acid hybridization with a 32P-labeled DNA probe prepared from a fragment of HSV DNA cloned in a plasmid vector. This assay can detect 5 X 10(4) plaque-forming units of cell-free HSV and as few as four virus-infected cells. The assay has a sensitivity of 78% and a specificity of 100% compared to virus culture for the detection of HSV in swab specimens from genital lesions. No hybridization is observed with uninfected, varicella-zoster virus infected, or cytomegalovirus infected cells, and specimens from herpes zoster lesions are uniformly negative. While hybridization with a 32P-labeled probe is not optimally suited for routine diagnostic use, this report establishes the feasibility of using nucleic acid hybridization to detect HSV in clinical specimens.

Detection of genital herpes simplex infections by a tissue culture-fluorescent-antibody technique with biotin-avidin

Several cell lines were evaluated for their suitability for rapid detection of herpes simplex virus (HSV) from clinical genital specimens. Human foreskin fibroblast (Flow 7000) cells were found to be most suitable in terms of sensitivity and adherence characteristics. HSV in clinical specimens was isolated by a standard tissue culture method by monitoring the cytopathic effect, and the titers of the HSV-positive specimens were determined. More than 65% of the HSV-positive genital specimens showed titers of less than or equal to 10(4) 50% tissue culture infective doses per ml. The standard tissue culture-cytopathic effect method required 3 to 10 days for detection of HSV in clinical specimens of low infectivity. A more rapid technique was developed which involved a short-term tissue culture (24 h) on Lab-Tek chambers followed by staining with biotin-linked HSV antibody and avidin-fluorescein conjugate. Because of the high binding affinity of this system due to multiple binding of biotin to avidin and multiple attachment of biotin to the antibody molecule, the biotin-avidin fluorescent-antibody technique produced a quality of fluorescence far superior to that of the conventional fluorescent-antibody techniques. The tissue culture-biotin-avidin fluorescent-antibody method was as sensitive as the tissue culture-cytopathic effect test. This method provides an improved, more rapid test (26 h) for detecting HSV in clinical specimens.

Genital herpes simplex--concepts and treatment

Genital herpes simplex is an increasingly common venereal disease caused by either herpes simplex virus type 1 or 2. The disease can be manifested in a primary and/or recurrent form, the clinical features and complications of which are reviewed. Potential problems include psychosocial difficulties, neonatal herpes simplex infections, and the possibility of an oncogenic role in cervical cancer. Diagnostic modalities, prophylactic measures, and management technics are discussed.

Comparison of viral isolation, direct immunofluorescence, and indirect immunoperoxidase techniques for detection of genital herpes simplex virus infection

Seventy-six consecutive patients presenting to a genital herpes simplex virus (HSV) clinic were enrolled in a study comparing viral isolation (VI), indirect immunoperoxidase (indirect IP), and direct immunofluorescence (direct FA) techniques for the detection of HSV antigen. Of the 76 patients, 61 (80%) demonstrated HSV by VI, compared with 66% by indirect IP and 55% by direct FA (P less than 0.05). Genital lesions from nine patients demonstrated HSV antigen by direct FA or indirect IP but were VI negative; eight of nine patients had subsequent episodes of genital HSV confirmed by VI. During the vesicular-pustular stage of the disease, VI was positive in 90%, indirect IP was positive in 76%, and direct FA was positive in 71% of the lesions, whereas with ulcerative lesions, VI was positive in 72%, indirect IP was positive in 55%, and direct FA was positive in 38%. These commercially available rapid viral diagnostic techniques are specific and useful, if adequate specimens are obtained from early genital lesions.