Virological diagnosis of herpes simplex virus 1 esophagitis by quantitative real-time PCR assay

Immunohistochemical diagnosis of human infectious diseases: a review

BACKGROUND

Immunohistochemistry (IHC) using monoclonal and polyclonal antibodies is a useful diagnostic method for detecting pathogen antigens in fixed tissues, complementing the direct diagnosis of infectious diseases by PCR and culture on fresh tissues. It was first implemented in a seminal publication by Albert Coons in 1941.

MAIN BODY

Of 14,198 publications retrieved from the PubMed, Google, Google Scholar and Science Direct databases up to December 2021, 230 were selected for a review of IHC techniques, protocols and results. The methodological evolutions of IHC and its application to the diagnosis of infectious diseases, more specifically lice-borne diseases, sexually transmitted diseases and skin infections, were critically examined. A total of 59 different pathogens have been detected once in 22 different tissues and organs; and yet non-cultured, fastidious and intracellular pathogens accounted for the vast majority of pathogens detected by IHC. Auto-IHC, incorporating patient serum as the primary antibody, applied to diseased heart valves surgically collected from blood culture-negative endocarditis patients, detected unidentified Gram-positive cocci and microorganisms which were subsequently identified as Coxiella burnetii, Bartonella quintana, Bartonella henselae and Tropheryma whipplei. The application of IHC to ancient tissues dated between the ends of the Ptolemaic period to over 70 years ago, have also contributed to paleomicrobiology diagnoses.

CONCLUSION

IHC plays an important role in diagnostic of infectious diseases in tissue samples. Paleo-auto-IHC derived from auto-IHC, is under development for detecting non-identified pathogens from ancient specimens.

Endoscopic tissue sampling - Part 1: Upper gastrointestinal and hepatopancreatobiliary tracts. European Society of Gastrointestinal Endoscopy (ESGE) Guideline

1: ESGE recommends that, where there is a suspicion of eosinophilic esophagitis, at least six biopsies should be taken, two to four biopsies from the distal esophagus and two to four biopsies from the proximal esophagus, targeting areas with endoscopic mucosal abnormalities. Distal and proximal biopsies should be placed in separate containers.Strong recommendation, low quality of evidence. 2: ESGE recommends obtaining six biopsies, including from the base and edge of the esophageal ulcers, for histologic analysis in patients with suspected viral esophagitis.Strong recommendation, low quality of evidence. 3: ESGE recommends at least six biopsies are taken in cases of suspected advanced esophageal cancer and suspected advanced gastric cancer.Strong recommendation, moderate quality of evidence. 4: ESGE recommends taking only one to two targeted biopsies for lesions in the esophagus or stomach that are potentially amenable to endoscopic resection (Paris classification 0-I, 0-II) in order to confirm the diagnosis and not compromise subsequent endoscopic resection.Strong recommendation, low quality of evidence. 5: ESGE recommends obtaining two biopsies from the antrum and two from the corpus in patients with suspected Helicobacter pylori infection and for gastritis staging.Strong recommendation, low quality of evidence. 6: ESGE recommends biopsies from or, if endoscopically resectable, resection of gastric adenomas.Strong recommendation, moderate quality of evidence. 7: ESGE recommends fine-needle aspiration (FNA) and fine-needle biopsy (FNB) needles equally for sampling of solid pancreatic masses.Strong recommendation, high quality evidence. 8: ESGE suggests performing peroral cholangioscopy (POC) and/or endoscopic ultrasound (EUS)-guided tissue acquisition in indeterminate biliary strictures. For proximal and intrinsic strictures, POC is preferred. For distal and extrinsic strictures, EUS-guided sampling is preferred, with POC where this is not diagnostic.Weak recommendation, low quality evidence. 9: ESGE suggests obtaining possible non-neoplastic biopsies before sampling suspected malignant lesions to prevent intraluminal spread of malignant disease.Weak recommendation, low quality of evidence. 10: ESGE suggests dividing EUS-FNA material into smears (two per pass) and liquid-based cytology (LBC), or the whole of the EUS-FNA material can be processed as LBC, depending on local experience.Weak recommendation, low quality evidence.

Clinical and Histopathologic Features Can Help Target Immunohistochemical Stain Use in the Diagnosis of Viral Esophagitis

OBJECTIVES

Herpes simplex virus (HSV) and cytomegalovirus (CMV) immunohistochemical stains (IHC) are frequently applied on esophageal biopsies. Our aims were to identify IHC use patterns in viral esophagitis (VE), and clinicopathologic features of VE that could guide IHC use.

METHODS

We included 58 VE cases and 60 controls, defined as patients with negative HSV/CMV IHC between January 2006 and July 2017. Biopsies were reviewed and histologic features and clinical data recorded.

RESULTS

Thirteen cases required IHC for diagnosis. IHC was performed in 13 HSV and 5 CMV cases where diagnostic viral inclusions were present. VE patients were more likely to have endoscopic ulcer (P=0.002) and be immunocompromised (P<0.001). Pretest clinical concern for VE was common (P=0.006). Histologically, VE patients were more likely to have ulcer (P=0.004), ulcer exudate rich in neutrophils and histiocytes (P=0.001), neutrophils in squamous mucosa (P<0.001), histiocyte aggregates >15 (P<0.001) and spongiosis (P<0.001). Controls had frequent eosinophils, alone (P=0.008) or admixed with other inflammatory cells (P<0.0001).

CONCLUSIONS

IHC is used in VE biopsies despite definite viral inclusions on hematoxylin and eosin and in patients without concerning histology or clinical concern for VE. History, endoscopic findings, and histology can be used to better target IHC use in VE.

Rare Etiology of Odynophagia in a Female Adolescent

Herpes esophagitis (HE) is a rare condition in immunocompetent adolescents. However, it commonly occurs as a primary infection in younger individuals. Herein, we report a 16-year-old female patient who had a history of fever for 5 days, odynophagia, and orolabial herpes infection for 7 days. Clusters of painful vesicles on an erythematous base on the lips, gingiva, and palate were observed on physical examination. Further, esophagogastroduodenoscopy revealed diffuse linear ulcerations in the distal esophagus. The patient then received the following treatment: intravenous (I.V.) acyclovir 5 mg/kg three times a day, I.V. omeprazole 40 mg two times a day, and acyclovir 5% cream four times a day. After 8 days of admission, the patient was discharged. A follow-up esophagogastroduodenoscopy was performed 7 weeks after discharge, and the results revealed that the esophageal mucosa had a normal appearance. The effect of antiviral treatment against HE remains unknown in these patients. Nevertheless, it is believed to accelerate the healing process in individuals with esophageal mucosal barrier damage. To the best of our knowledge, this case of a female adolescent with an intact immune system is the sixth case of herpes simplex esophagitis to be reported in the literature.

Machine learning approach for differentiating cytomegalovirus esophagitis from herpes simplex virus esophagitis

The endoscopic features between herpes simplex virus (HSV) and cytomegalovirus (CMV) esophagitis overlap significantly, and hence the differential diagnosis between HSV and CMV esophagitis is sometimes difficult. Therefore, we developed a machine-learning-based classifier to discriminate between CMV and HSV esophagitis. We analyzed 87 patients with HSV esophagitis and 63 patients with CMV esophagitis and developed a machine-learning-based artificial intelligence (AI) system using a total of 666 endoscopic images with HSV esophagitis and 416 endoscopic images with CMV esophagitis. In the five repeated five-fold cross-validations based on the hue-saturation-brightness color model, logistic regression with a least absolute shrinkage and selection operation showed the best performance (sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and area under the receiver operating characteristic curve: 100%, 100%, 100%, 100%, 100%, and 1.0, respectively). Previous history of transplantation was included in classifiers as a clinical factor; the lower the performance of these classifiers, the greater the effect of including this clinical factor. Our machine-learning-based AI system for differential diagnosis between HSV and CMV esophagitis showed high accuracy, which could help clinicians with diagnoses.

[Evaluation and management of infectious esophagitis in immunocompromised patients and immunocompetent individuals]

Among the many causes of the inflammatory process in the esophagus, infectious diseases are becoming increasingly important due to their steady growth. Previously esophageal infections have traditionally been associated with immunodeficiency syndromes, but now in clinical practice, these disorders are becoming increasingly recognized in immunocompetent individuals. Early diagnosis of infectious esophagitis is necessary to develop effective treatment tactics, and, as a result, reduce the risk of complications and adverse outcomes of the disease. This study reviewed the most clinical relevant pathogens of infectious esophagitis, both among patients with immunodeficiency and among healthy individuals. Specific diagnostic, risk factors, clinical presentation and therapeutic features were considered depending on the immune status of patients.

HSV-1 Ulcers as an Infrequent Cause of Hematochezia

We report a 62-year-old woman in the intensive care unit who developed hematochezia. Her endoscopic findings revealed diffusely bleeding esophageal ulcers related to herpes simplex virus. The bleeding was treated successfully with Hemospray.

Characterization of polyclonal antibodies to Herpes Simplex Virus types 1 and 2

Infections with herpes simplex virus (HSV) types 1 and 2 have been linked to oral, facial, genital lesions, as well as some visceral organ changes in patients under immunosuppressed conditions. Immunohistochemistry (IHC) with HSV antibodies is used for identification of the viruses in tissue samples. In this study, two polyclonal antibodies, prepared separately with HSV-1 and HSV-2 immunogens, were characterized in comparison to a monoclonal antibody to HSV-1 (10A3). The polyclonal anti-HSV-1 and monoclonal antibody 10A3 were shown to be reactive to viral proteins of both HSV-1 and HSV-2 on Western blots, while the polyclonal anti-HSV-2 was reactive to HSV-2 proteins, but not to those of HSV-1. Cross-reactivity was not observed to proteins of six other frequently encountered herpes viruses. IHC characterization was performed on 29 cases of HSV-infected tissue samples, 61 samples infected with other herpes viruses and 35 samples without known infection. By IHC, the polyclonal anti-HSV-1 and a monoclonal antibody 10A3 exhibited a signal, mainly in a nuclear pattern, in all of the HSV-infected samples and not in other tissue types. A positive signal, mainly in the cytoplasm, was identified with the polyclonal anti-HSV-2 in 21 of the 29 HSV-infected samples. Genotyping analysis was successful in 14 of the HSV-infected samples, with IHC HSV-2 positivity correlative to the HSV-2 genotype. The results demonstrate that these antibodies are useful tools for identification of HSV-1 and HSV-2, and their combinatorial application may help to distinguish between these two types of infection.

Impact of different types of herpesviral infections in the oral cavity

The herpesviruses are ubiquitous, doubled-stranded DNA viruses that can reactivate under conditions such as immunosuppressive therapy, acquired immunodeficiency syndrome, malnutrition, and immunosenescence. There are eight types of herpesviruses: Human herpesvirus simplex (HSV) type I (HSV-1) and HSV type II (HSV-2), varicella-zoster virus (VZV), epstein-Barr virus (EBV), cytomegalovirus, human herpesvirus (HHV)-6, HHV-7, and HHV-8 or Kaposi’s sarcoma herpesvirus. Some of these viruses can infect the oral cavity, leading to different types of lesions. Specifically, labial herpes (HSV-1 and less frequently HSV-2), zoster (VZV), infectious mononucleosis and oral hairy leukoplakia (EBV), and Kaposi’s Sarcoma (HHV-8) are the most common viruses infecting the oral cavity. Some of these viruses can act in synergy with other herpesviruses or as distinct infectious agents. Other herpesviruses may have indirect effects in periodontal disease. The diagnosis is frequently based on signs and symptoms and depends on the experience of the examiner. Cytopathologic and/or histopathologic examination as well as immunological methods such as ELISA could help to elucidate cases. In addition, molecular techniques which can be sensitive and specific have been reported in the literature. These methods require low amounts of sample and could offer results faster than other traditional methods.

Real-time polymerase chain reaction for the diagnosis of necrotizing herpes stromal keratitis

AIM

To design, optimize and validate a rapid, internally controlled real-time polymerase chain reaction (RT-PCR) test for herpes simplex virus (HSV) in the diagnosis of necrotizing herpes stromal keratitis.

METHODS

Tears alone or together with corneal epithelium scrapings from 30 patients (30 eyes) suspected of necrotizing herpes stromal keratitis were tested for HSV DNA by RT-PCR. The samples were collected during the first visit and then on the subsequent 7, 14, 28, 42, and 56d. The symptoms of the patients were scored before treatment to determine the correlation between HSV concentration in the corneal epithelium scrapings and clinical scores.

RESULTS

The positive rate (46.4%) in the corneal epithelium group before the therapy was significantly higher than that (13.3%) in the tears group (P=0.006). There were 13 positive HSV patients before the therapy, the concentration of HSV DNA in corneal epithelium scrapings group was significantly higher than that in the tears group (paired t-test, P=0.0397). Multilevel mixed-effects model analysis showed that the difference between the corneal epithelium scrapings group and the tears group was statistically significant (P=0.0049). The Spearman rank correlation analysis indicated a positive correlation between the HSV concentration in the corneal epithelium scrapings and clinical scores before the treatment (r=0.844, P<0.0001).

CONCLUSION

RT-PCR appears to be a powerful molecular tool for the diagnosis of necrotizing herpes stromal keratitis.

Evaluation and Management of Infectious Esophagitis in Immunocompromised and Immunocompetent Individuals

Among the many inflammatory processes that may account for esophageal symptoms, infection represents an important etiologic category with numerous clinically relevant subdivisions. While features of the history and physical exam are informative, diagnosis often hinges on endoscopic visualization and histopathologic analysis. This chapter will review in series the most clinically relevant causative agents for infectious esophagitis, with specific diagnostic and therapeutic features of note divided into one of two immune milieus. Our discussion focuses primarily on Candida species, herpes simplex virus, and cytomegalovirus as the most common causes of infectious esophagitis while also addressing a number of less common pathogens worth keeping in mind.

Upper gastrointestinal microbiota and digestive diseases

Metagenomics which combines the power of genomics, bioinformatics, and systems biology, provide new access to the microbial world. Metagenomics permit the genetic analysis of complex microbial populations without requiring prior cultivation. Through the conceptual innovations in metagenomics and the improvements in DNA high-throughput sequencing and bioinformatics analysis technology, gastrointestinal microbiology has entered the metagenomics era and become a hot topic worldwide. Human microbiome research is underway, however, most studies in this area have focused on the composition and function of the intestinal microbiota and the relationship between intestinal microbiota and metabolic diseases (obesity, diabetes, metabolic syndrome, etc.) and intestinal disorders [inflammatory bowel disease, colorectal cancer, irritable bowel syndrome (IBS), etc.]. Few investigations on microbiota have been conducted within the upper gastrointestinal tract (esophagus, stomach and duodenum). The upper gastrointestinal microbiota is essential for several gastrointestinal illnesses, including esophagitis, Barrett’s esophagus, and esophageal carcinoma, gastritis and gastric cancer, small intestinal bacterial overgrowth, IBS and celiac disease. However, the constitution and diversity of the microbiota in different sections of the upper gastrointestinal tract under health and various disease states, as well as the function of microbiota in the pathogenesis of various digestive diseases are still undefined. The current article provides an overview of the recent findings regarding the relationship between upper gastrointestinal microbiota and gastrointestinal diseases; and discusses the study limitations and future directions of upper gastrointestinal microbiota research.