Direct immunofluorescence assay compared to cell culture for the diagnosis of mucocutaneous herpes simplex virus infections in children

Sexually Transmitted Infections Treatment Guidelines, 2021

These guidelines for the treatment of persons who have or are at risk for sexually transmitted infections (STIs) were updated by CDC after consultation with professionals knowledgeable in the field of STIs who met in Atlanta, Georgia, June 11–14, 2019. The information in this report updates the 2015 guidelines. These guidelines discuss 1) updated recommendations for treatment of Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis; 2) addition of metronidazole to the recommended treatment regimen for pelvic inflammatory disease; 3) alternative treatment options for bacterial vaginosis; 4) management of Mycoplasma genitalium; 5) human papillomavirus vaccine recommendations and counseling messages; 6) expanded risk factors for syphilis testing among pregnant women; 7) one-time testing for hepatitis C infection; 8) evaluation of men who have sex with men after sexual assault; and 9) two-step testing for serologic diagnosis of genital herpes simplex virus. Physicians and other health care providers can use these guidelines to assist in prevention and treatment of STIs.

Diagnosis of Herpes Simplex Virus: Laboratory and Point-of-Care Techniques

Herpes is a widespread viral infection caused by the herpes simplex virus (HSV) that has no permanent cure to date. There are two subtypes, HSV-1 and HSV-2, that are known to cause a variety of symptoms, ranging from acute to chronic. HSV is highly contagious and can be transmitted via any type of physical contact. Additionally, viral shedding can also happen from asymptomatic infections. Thus, early and accurate detection of HSV is needed to prevent the transmission of this infection. Herpes can be diagnosed in two ways, by either detecting the presence of the virus in lesions or the antibodies in the blood. Different detection techniques are available based on both laboratory and point of care (POC) devices. Laboratory techniques include different biochemical assays, microscopy, and nucleic acid amplification. In contrast, POC techniques include microfluidics-based tests that enable on-spot testing. Here, we aim to review the different diagnostic techniques, both laboratory-based and POC, their limits of detection, sensitivity, and specificity, as well as their advantages and disadvantages.

Herpes simplex virus infections in solid organ transplantation: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of HSV in the pre- and post-transplant period. A majority of transplant recipients are seropositive for HSV-1 or 2. Compared with immunocompetent persons, SOT recipients shed HSV more frequently, have more severe clinical manifestations, and are slower to respond to therapy. Most HSV infection is diagnosed on clinical grounds, but patients may present with atypical lesions and/or other clinical manifestations. Acquisition from the donor is rare. Polymerase chain reaction is the preferred diagnostic test unless culture is needed for resistance testing. For limited mucocutaneous lesions, oral therapy can be used; however, in severe, disseminated, visceral or CNS involvement, acyclovir doses of up to 10 mg/kg every 8 hours intravenously should be initiated. Acyclovir-resistant HSV is less common in SOT patients than in HSCT and can be treated with foscarnet, though other novel therapies are currently under investigation. HSV-specific prophylaxis should be considered for all HSV-1 and HSV-2-seropositive organ recipients who are not receiving antiviral medication for CMV prevention that has activity against HSV.

Herpes Simplex Virus and Varicella-Zoster Virus

The most common specimens from immunocompromised patients that are analyzed for detection of herpes simplex virus (HSV) or varicella-zoster virus (VZV) are from skin lesions. Many types of assays are applicable to these samples, but some, such as virus isolation and direct fluorescent antibody testing, are useful only in the early phases of the lesions. In contrast, nucleic acid (NA) detection methods, which generally have superior sensitivity and specificity, can be applied to skin lesions at any stage of progression. NA methods are also the best choice, and sometimes the only choice, for detecting HSV or VZV in blood, cerebrospinal fluid, aqueous or vitreous humor, and from mucosal surfaces. NA methods provide the best performance when reliability and speed (within 24 hours) are considered together. They readily distinguish the type of HSV detected or the source of VZV detected (wild type or vaccine strain). Nucleic acid detection methods are constantly being improved with respect to speed and ease of performance. Broader applications are under study, such as the use of quantitative results of viral load for prognosis and to assess the efficacy of antiviral therapy.

Light microscopy, culture, molecular, and serologic methods for detection of herpes simplex virus

Herpes simplex virus 1 (HSV-1) and 2 (HSV-2) cause a variety of human diseases, ranging from acute to chronic and mild to severe. The absence of curative therapy results in lifelong carriage marked by recurrent outbreaks and allows transmission of the virus to uninfected individuals. Nonspecific lesions, variable presentation, and chronic carriage necessitate the use of different laboratory testing methods appropriate for each presentation. A thorough understanding of the performance characteristics and limitations of available tests is critical for selection of the appropriate test and interpretation of results. Clinical sensitivity, specificity, and selection of the appropriate methodology is paramount to avoid misdiagnosis and guide therapy. In this article we review the different methods for detection and typing of HSV, including light microscopy, culture, serology, and nucleic acid-based tests. We discuss the strengths and weaknesses of each method for diagnosing HSV infection, cite performance characteristics, and review appropriate clinical uses.

Comparison of Simplexa HSV 1 & 2 PCR with culture, immunofluorescence, and laboratory-developed TaqMan PCR for detection of herpes simplex virus in swab specimens

The Simplexa HSV 1 & 2 direct PCR assay was compared with conventional cell culture, cytospin-enhanced direct fluorescent antibody (DFA), and a laboratory-developed real-time TaqMan PCR (LDT HSV PCR) using extracted nucleic acid for the detection of herpes simplex virus (HSV) in dermal, genital, mouth, ocular, and other swab samples. One hundred seventy-one swabs were tested prospectively, and 58 were positive for HSV (34 HSV-1 and 24 HSV-2). Cytospin-DFA detected 50 (86.2%), conventional cell culture 51 (87.9%), Simplexa direct 55 (94.8%), and LDT HSV PCR 57 (98.3%) of 58 true positives. Simplexa direct detected more positives than DFA and culture, but the differences were not significant (P = 0.0736 and P = 0.3711, respectively, by the McNemar test). Samples that were positive by all methods (n = 48) were strong positives (LDT cycle threshold [CT] value, 14.4 to 26.1). One strongly positive sample was falsely negative by LDT HSV PCR due to a failure of TaqMan probe binding. Three samples falsely negative by Simplexa direct had high CT values by LDT HSV PCR (LDT CT, 35.8 to 38.2). Omission of the DNA extraction step by Simplexa direct led to a drop in sensitivity compared to the sensitivity of LDT HSV PCR using extracted samples (94.8% versus 98.3%, respectively), but the difference was not significant (P = 0.6171). Simplexa HSV 1 & 2 direct PCR was the most expensive but required the least training of the assays used, had the lowest hands-on time and fastest assay time (75 min, versus 3 h by LDT HSV PCR), and provided the HSV type.

Cutaneous lumbosacral Herpes simplex virus among patients hospitalized for an advanced disease

BACKGROUND

Cutaneous Herpes simplex virus (HSV) infections are regularly observed in lumbosacral areas, and many are refractory to appropriate initial diagnosis and management.

OBJECTIVE

We aimed to evaluate the incidence of lumbosacral HSV among advanced disease patients, to estimate their survival index from HSV onset, and to describe their clinical and virological characteristics.

METHODS

A prospective, descriptive study was conducted in a palliative and continuous care centre, collecting patients with suspected cutaneous HSV lesions in the lumbosacral area.

RESULTS

From 2008 to 2010, 24 patients were included: 19 had HSV-2 confirmed by at least one laboratory test. Incidence of HSV-2 was 2.67% (1.73-4.33%, 95% CI). No age, gender or survival differences were observed compared to the global population in the centre. Most lesions were detected early as vesicles (14/24) or small ulcers. Sensitivity was good for all diagnostic methods (62.5% for immunofluorescence and 79.2% for culture and/or PCR). Outcome was favourable under classical antiherpetic drugs and topical antiseptic dressing.

CONCLUSIONS

Cutaneous lumbosacral HSV remains uncommon in patients hospitalized with advanced diseases. Most of these patients suffer from pressure ulcers or other dermatitis; we advocate increased attention of this diagnosis to avoid skin complications and added pain.