Cytomegalovirus infection in gastrointestinal tracts of patients infected with HIV-1 or AIDS

Performance of Cytomegalovirus Real-Time Polymerase Chain Reaction Assays of Fecal and Plasma Specimens for Diagnosing Cytomegalovirus Colitis

INTRODUCTION

Cytomegalovirus (CMV) viral load detected by real-time polymerase chain reaction (PCR) in plasma or stool may facilitate detection of CMV colitis.

METHODS

This prospective study enrolled 117 patients with clinically suspected CMV colitis. Patients presenting with gastrointestinal symptoms and having increased risk of CMV infection were eligible. All participants underwent colonoscopy with tissue biopsy. Five patients underwent colonoscopy twice because of clinical recurrence, resulting in a total of 122 colonoscopies. Stool CMV-PCR and plasma CMV-PCR were performed within 7 days before/after colonoscopy. Twenty asymptomatic volunteers also underwent the same protocol.

RESULTS

Twenty-seven (23.1%) of 122 colonoscopies yielded positive for CMV colitis. The sensitivity and specificity was 70.4% and 91.6% for stool CMV-PCR and 66.7% and 94.7% for plasma CMV-PCR, respectively. The sensitivity of either positive plasma or positive stool CMV-PCR was 81.5%, which is significantly higher than that of plasma CMV-PCR alone ( P = 0.045). However, positive results from both tests yielded a specificity of 95.8%, which is significantly higher than that of stool CMV-PCR alone ( P = 0.045). There was a good and significant correlation between stool CMV-PCR and plasma CMV-PCR ( r = 0.71, P < 0.01), and both tests significantly correlated with the cytomegalic cell count ( r = 0.62, P < 0.01 for stool and r = 0.64, P < 0.01 for plasma). There were no positive stool or plasma CMV-PCR assays among volunteers.

DISCUSSION

The results of this study strongly suggest that the combination of stool CMV-PCR and plasma CMV-PCR can be used to confidently rule in (both positive) or rule out (both negative) a diagnosis of CMV colitis.

Emergency gastrointestinal tract operation associated with cytomegalovirus infection

Purpose

Cytomegalovirus (CMV) infection is common in immunocompromised patients. Enterocolitis caused by CMV infection can lead to perforation and bleeding of the gastrointestinal (GI) tract, which requires emergency operation. We investigated the demographics and outcomes of patients who underwent emergency operation for CMV infection of the GI tract.

Methods

This retrospective study was conducted between January 2010 and December 2020. Patients who underwent emergency GI operation and were diagnosed with CMV infection through a pathologic examination of the surgical specimen were included. The diagnosis was confirmed using immunohistochemical staining and evaluated by experienced pathologists.

Results

A total of 27 patients who underwent operation for CMV infection were included, 18 of whom were male with a median age of 63 years. Twenty-two patients were in an immunocompromised state. Colon (37.0%) and small bowel (37.0%) were the most infected organs. CMV antigenemia testing was performed in 19 patients; 13 of whom showed positive results. The time to diagnose CMV infection from operation and time to start ganciclovir treatment were median of 9 days. The reoperation rate was 22.2% and perforation was the most common cause of reoperation. In-hospital mortality rate was 25.9%.

Conclusion

CMV infection in the GI tract causes severe effects, such as hemorrhage or perforation, in immunocompromised patients. When these outcomes are observed in immunocompromised patients, suspicion of CMV infection and further evaluation for CMV detection in tissue specimens is required for proper treatment.

Liver Abscess caused by Cytomegalovirus in a Patient with Acquired Immunodeficiency Syndrome

Cytomegalovirus (CMV) causes severe infection in immunocompromised patients, especially those with acquired immunodeficiency syndrome (AIDS), those who have undergone organ transplantation, and/or those who are being treated with steroids. In patients with AIDS, CMV is the most common pathogen that causes opportunistic infections. Here, we present a case of liver abscess due to CMV in a 58-year-old man diagnosed with AIDS. At the time of the study, his CD4 T lymphocyte count was 39 cells/mm³, and his human immunodeficiency virus (HIV) ribonucleic acid (RNA) level was 411,000 copies/mL. Upon presentation, he complained of upper abdominal pain. Ultrasonography-guided percutaneous drainage of the liver abscess was performed, and polymerase chain reaction analysis of the drained pus was positive for CMV. He was treated with intravenous ganciclovir, after which he recovered fully. In conclusion, our patient represents, to our knowledge, the first described case of liver abscess caused by CMV in an AIDS patient, which was probably facilitated by severe immunodeficiency.

Virus-associated disruption of mucosal epithelial tight junctions and its role in viral transmission and spread

Oropharyngeal, airway, intestinal, and genital mucosal epithelia are the main portals of entry for the majority of human pathogenic viruses. To initiate systemic infection, viruses must first be transmitted across the mucosal epithelium and then spread across the body. However, mucosal epithelia have well-developed tight junctions, which have a strong barrier function that plays a critical role in preventing the spread and dissemination of viral pathogens. Viruses can overcome these barriers by disrupting the tight junctions of mucosal epithelia, which facilitate paracellular viral penetration and initiate systemic disease. Disruption of tight and adherens junctions may also release the sequestered viral receptors within the junctional areas, and liberation of hidden receptors may facilitate viral infection of mucosal epithelia. This review focuses on possible molecular mechanisms of virus-associated disruption of mucosal epithelial junctions and its role in transmucosal viral transmission and spread.

Virus-associated disruption of mucosal epithelial tight junctions and its role in viral transmission and spread

Oropharyngeal, airway, intestinal, and genital mucosal epithelia are the main portals of entry for the majority of human pathogenic viruses. To initiate systemic infection, viruses must first be transmitted across the mucosal epithelium and then spread across the body. However, mucosal epithelia have well-developed tight junctions, which have a strong barrier function that plays a critical role in preventing the spread and dissemination of viral pathogens. Viruses can overcome these barriers by disrupting the tight junctions of mucosal epithelia, which facilitate paracellular viral penetration and initiate systemic disease. Disruption of tight and adherens junctions may also release the sequestered viral receptors within the junctional areas, and liberation of hidden receptors may facilitate viral infection of mucosal epithelia. This review focuses on possible molecular mechanisms of virus-associated disruption of mucosal epithelial junctions and its role in transmucosal viral transmission and spread.

Cytomegalovirus Colitis in Primary Hypogammaglobulinemia With Normal CD4+ T Cells: Deficiency of CMV-Specific CD8+ T Cells

CMV colitis has been reported in immunocompromized patients with severe deficiency of CD4+ T cells and T cell functions. In this study we present an extensive immunological analysis in a patient with primary hypogammaglobulinemia and CMV colitis who had normal numbers of CD3+T, CD4+T and CD8+T cells, and normal T cell proliferative responses to mitogens and recall antigens. Naïve (T_N), central (T_CM), and effector (T_EM) memory subsets of CD4+ and CD8+ T cells, Granzyme+ and Perforin+ CD8+ T cells, PD-1+ T cells, CD4 Treg, CD8 Treg, and CMV tetramer specific CD8+ T cells were analyzed with specific antibodies and isotype controls using multicolor flow cytometry. CD8 T_EM, Granzyme+ and Perforin+, and PD-1 CD8+T cells were increased, whereas CD8 T_N and CD8 T_CM cells were decreased in the patient as compared to controls. CMV tetramer+ CD8+ T cells were decreased in the patient. These data demonstrate that a deficiency of CMV-specific CD8+ T cells even in the presence of normal CD4+ T cell numbers and normal T cell functions may predispose patients with primary hypogammaglobulinemia to CMV colitis.

Routine Hematoxylin and Eosin Stain Is Specific for the Diagnosis of Cytomegalovirus Infection in Gastrointestinal Biopsy Specimens

BACKGROUND

Gastrointestinal cytomegalovirus (CMV) infection is a serious complication in immunocompromised patients; clinicians often expect expedited results for biopsy specimens. Our goal is to determine the accuracy of identification of CMV on hematoxylin and eosin (H&E) stain.

METHODS AND RESULTS

A total of 361 biopsy specimens from 273 patients with suspicion for CMV infection were retrieved. CMV was detected by immunohistochemistry (IHC) in 37 specimens acquired from 33 individual patients (average age = 54 years). Among the CMV-positive patients, 29 (88%) were reported to be immunosuppressed. Colon was the most common affected location. Of 37 CMV-positive specimens by IHC, 28 were positive by H&E (76%), 6 were negative (16%), and 3 were suspicious (8%). Of the 29 positive specimens on H&E, 28 were confirmed by IHC (97%) and 1 was indeterminate (3%). The sensitivity and specificity of H&E were 84% and 94%, respectively; the positive predictive value was 97%, and the negative predictive value was 93% ( P < .00001).

CONCLUSION

Our results show that a preliminary diagnosis of CMV infection, based on H&E stains, can be reported with high specificity and low risk for false-positive results. Suspicious cases should be deferred pending the result of IHC stains.

Cytomegalovirus Disease of the Upper Gastrointestinal Tract: A 10-Year Retrospective Study

Background and Aims

Cytomegalovirus (CMV) disease of the gastrointestinal (GI) tract is a major cause of morbidity and mortality in immunocompromised patients. The colon is the most commonly affected site, and the literature is scarce regarding CMV disease of the upper GI tract. Therefore, our study aimed to evaluate the clinical and endoscopic features of upper GI CMV disease.

Methods

This 10-year retrospective study included all patients with a histopathological diagnosis of upper GI CMV infection. Patients' clinical, endoscopic, therapy, and follow-up data were collected from medical records.

Results

Twelve patients with histopathologically proven upper GI CMV disease were identified (age 61 ± 18 years, 50% men). Most of the patients were immunocompromised (75%) due to acquired immunodeficiency syndrome (AIDS), malignancy, and/or immunosuppressive therapy. In the remainder (25%), the disease occurred in the absence of immunodeficiency and immunosuppression. Three patients (all with AIDS) presented with disseminated CMV infection. In the majority of the cases (83%), upper GI CMV disease was symptomatic, and the most common clinical presentations were odynophagia/dysphagia (25%) and nausea/vomiting (25%). Endoscopically, there were 5 cases of esophagitis (42%) and 7 cases of gastritis (58%). The lower esophagus (33%) and the gastric antrum (42%) were the most frequently affected GI sites. Regardless of the location, mucosal ulceration was the most common endoscopic finding (75%) and was associated with very deep ulceration resembling cavitation in 2 cases. Other endoscopic features were mucosal edema, hyperemia, and nodularity (25%). Eleven patients (92%) received antiviral treatment (duration 26 ± 12 days). The 1-month and 1-year mortality rates were 16.7 and 25%, respectively.

Conclusions

Upper GI CMV disease can occur in the absence of immunodeficiency and immunosuppression. It is usually symptomatic, and mucosal ulceration is often evident at endoscopy. It is associated with significant mortality; therefore, early diagnosis and adequate antiviral treatment are essential.

Replication of CMV in the gut of HIV-infected individuals and epithelial barrier dysfunction

Although invasive cytomegalovirus (CMV) disease is uncommon in the era of antiretroviral therapy (ART), asymptomatic CMV coinfection is nearly ubiquitous in HIV infected individuals. While microbial translocation and gut epithelial barrier dysfunction may promote persistent immune activation in treated HIV infection, potentially contributing to morbidity and mortality, it has been unclear whether CMV replication in individuals with no symptoms of CMV disease might play a role in this process. We hypothesized that persistent CMV replication in the intestinal epithelium of HIV/CMV-coinfected individuals impairs gut epithelial barrier function. Using a combination of state-of-the-art in situ hybridization technology (RNAscope) and immunohistochemistry, we detected CMV DNA and proteins and evidence of intestinal damage in rectosigmoid samples from CMV-positive individuals with both untreated and ART-suppressed HIV infection. Two different model systems, primary human intestinal cells differentiated in vitro to form polarized monolayers and a humanized mouse model of human gut, together demonstrated that intestinal epithelial cells are fully permissive to CMV replication. Independent of HIV, CMV disrupted tight junctions of polarized intestinal cells, significantly reducing transepithelial electrical resistance, a measure of monolayer integrity, and enhancing transepithelial permeability. The effect of CMV infection on the intestinal epithelium is mediated, at least in part, by the CMV-induced proinflammatory cytokine IL-6. Furthermore, letermovir, a novel anti-CMV drug, dampened the effects of CMV on the epithelium. Together, our data strongly suggest that CMV can disrupt epithelial junctions, leading to bacterial translocation and chronic inflammation in the gut and that CMV could serve as a target for therapeutic intervention to prevent or treat gut epithelial barrier dysfunction during HIV infection.

Double encephalitis with herpes simplex virus type II and cytomegalovirus in an elder Chinese: a case report

Herpes simplex encephalitis is a rare disease. In adults, most of the reported cytomegalovirus (CMV) infections are seen in immunocompromised patients. We present a case of 67-year-old Chinese male with the coinfection of CMV and herpes simplex virus type II (HSV-II). He had no history of being treated with immunosuppressants, showed symptoms of psychosis and was scored 109 on the Positive and Negative Syndrome Scale. This patient presented with a rare case of coinfection of CMV and herpes simplex virus type II with psychotic symptoms.

Seroprevalence of helicobacter pylori in human immunodeficiency virus-positive Patients and it's correlation with CD4(+) Lymphocyte Count

Background:

This study assessed the seroprevalence of Helicobacter pylori antibodies among Iranian patients with human immunodeficiency virus (HIV) infection. It also examines whether anti H. pylori seroprevalence was associated with the severity of the HIV infection or the antiretroviral treatment.

Material and Methods:

A total of 114 HIV-infected patients and 114 age and sex-matched controls, without symptoms referable to upper gastrointestinal tract were recruited. Blood samples were obtained from all subjects. Serum IgG and IgA against H. pylori measured using the enzyme-linked immunosorbent assay (ELISA).

Results:

The rate of anti H. pylori IgG seropositivity was 57.9% in HIV-infected patients and 28.95% in controls (P < 0.001), while the rate of IgA seropositivity was 2.64% in HIV patients and 31.57% in controls (P < 0.001). Although there was an increasing trend of higher IgG and IgA titre by increasing CD4 cell count in HIV-positive patients, it was not reach statistical significance. There was no statistical difference in the serology of anti H. pylori IgG and IgA between patients receiving antiretroviral therapy comparing untreated HIV patients.

Conclusions:

This study showed higher seroprevalence of H. pylori IgG along with lower seroprevalence of H. pylori IgA in HIV-positive patients compared matched controls.

Small bowel perforation due to CMV enteritis infection in an HIV-positive patient

BACKGROUND

Cytomegalovirus infection of the gastrointestinal tract is common and is more often seen in patients with acquired immunodeficiency syndrome (AIDS). Although small bowel infection is less common than infection of other parts of the gastrointestinal system, it may lead to perforation, an acute complication, with dreadful results.

CASE PRESENTATION

This article reports a case of Cytomegalovirus ileitis with multiple small bowel perforations in a young man with human immunodeficiency virus (HIV) infection. The patient developed abdominal pain with diarrhea and fever, and eventually acute abdomen with pneumoperitoneum. The patient had poor prognosis and deceased despite the prompt surgical intervention and the antiviral therapy he received. At pathology a remarkable finding was the presence of viral inclusions in smooth muscle fibers. The destruction of muscle cells was the main cause of perforation.

CONCLUSION

Morbidity and mortality associated with perforation from CMV enteritis in AIDS patients are high and the life expectancy is short. Cytomegalovirus disease is multifocal; therefore, excision of one portion of the gastrointestinal tract may be followed by a complication elsewhere. Our case elucidate that muscle cell destruction by the virus is a significant cause leading to perforation.

Cytomegalovirus infection of the colon presenting as a mass-like lesion

Cytomegalovirus (CMV) is responsible for the most common opportunistic infections in patients with acquired immunodeficiency syndrome (AIDS). The colon is a common site for these infections in patients positive for human immunodeficiency virus. CMV rarely presents as an intraluminal inflammatory mass in the colon. Here we report the case of a CMV infection presenting as a mass-like lesion in an AIDS patient. The clinical diagnosis of CMV infection is largely based on the characteristic endoscopic appearance. Endoscopic procedures are encouraged early in the course of CMV infection in immunocompromised patients. CMV pseudotumors along with malignancy should be part of the endoscopic evaluation in patients with AIDS.

Biopsy interpretation of colonic biopsies when inflammatory bowel disease is excluded

The interpretation of colonic biopsies related to inflammatory conditions can be challenging because the colorectal mucosa has a limited repertoire of morphologic responses to various injurious agents. Only few processes have specific diagnostic features, and many of the various histological patterns reflect severity and duration of the disease. Importantly the correlation with endoscopic and clinical information is often cardinal to arrive at a specific diagnosis in many cases.

Cytomegalovirus infection of the upper gastrointestinal tract: a clinical and pathological study of 30 cases

OBJECTIVE

The study reviews the endoscopic and histological features of human cytomegalovirus (HCMV) infections of the upper gastrointestinal (UGI) tract.

MATERIALS AND METHODS

Clinical histories, endoscopic findings and bioptic specimens of 30 cases of HCMV infection of the UGI tract, diagnosed in a University Hospital in a 10-year period, were reviewed. In all cases, viral inclusion bodies were detected in routine histopathological sections and the diagnosis was confirmed with immunohistochemistry.

RESULTS

Six patients were HIV+, whereas four had received organ transplantations, one was affected by common variable immunodeficiency and four had a recent history of malignancy. No other pathologic condition was evidenced in the remaining 15 cases. Mucosal alterations were endoscopically observed in the stomach (19 cases), esophagus (9), cardias (6) and duodenum (1), and multiple organs being synchronously affected in five patients (3 HIV+, 2 with history of malignancy). The antropyloric area was the most frequently affected site. Single ulcers were detected in 11 cases and multiple ulcers in 8, whereas mucosal thickenings (in the form of localized thickenings, polyps or rugal hypertrophy) were present in 13 patients. Thickenings of the mucosa were detected only in the stomach. At histology, necrotic material and granulation tissue were associated with moderate or marked lympho-plasmacytic infiltrate and foveolar hyperplasia in ulcerative lesions, whereas lesions labeled as mucosal thickenings showed mild or moderate chronic inflammatory infiltrate and foveolar hyperplasia.

CONCLUSIONS

Endoscopic manifestations of UGI tract involvement in HCMV infection are not specific, varying from erythematous mucosa to ulcers to mucosal thickenings.

Low prevalence of H. pylori infection in HIV-positive patients in the northeast of Brazil

Background

This study conducted in Northeastern Brazil, evaluated the prevalence of H. pylori infection and the presence of gastritis in HIV-infected patients.

Methods

There were included 113 HIV-positive and 141 age-matched HIV-negative patients, who underwent upper gastrointestinal endoscopy for dyspeptic symptoms. H. pylori status was evaluated by urease test and histology.

Results

The prevalence of H. pylori infection was significantly lower (p < 0.001) in HIV-infected (37.2%) than in uninfected (75.2%) patients. There were no significant differences between H. pylori status and gender, age, HIV viral load, antiretroviral therapy and the use of antibiotics. A lower prevalence of H. pylori was observed among patients with T CD4 cell count below 200/mm³; however, it was not significant. Chronic active antral gastritis was observed in 87.6% of the HIV-infected patients and in 780.4% of the control group (p = 0.11). H. pylori infection was significantly associated with chronic active gastritis in the antrum in both groups, but it was not associated with corpus chronic active gastritis in the HIV-infected patients.

Conclusion

We demonstrated that the prevalence of H. pylori was significantly lower in HIV-positive patients compared with HIV-negative ones. However, corpus gastritis was frequently observed in the HIV-positive patients, pointing to different mechanisms than H. pylori infection in the genesis of the lesion.

Infectious Diseases of the Lower Gastrointestinal Tract

Gastrointestinal (GI) infections are a major cause of morbidity and mortality worldwide. Although infectious organisms are often recovered by microbiological methods, surgical pathologists play an invaluable role in diagnosis. The lower GI tract, including the appendix, large bowel, and anus, harbors a wide variety of pathogens. Some infections are part of disseminated disease, whereas others produce clinicopathologic scenarios that are specific to the lower GI tract. This review focuses on selected infectious disorders of the lower GI tract that may be encountered by the general surgical pathologist, including viral, bacterial, fungal, and parasitic organisms, and including infections caused by food- and water-borne pathogens. Diagnostic gross and histologic features are discussed, as well as useful clinical features and ancillary diagnostic techniques. Pertinent differential diagnoses are also emphasized, including other inflammatory conditions of the gut (such as ischemia or idiopathic inflammatory bowel disease) that can be mimicked by lower GI infections.

Cytomegalovirus pseudotumor of the duodenum in a patient with AIDS: an unrecognized and potentially treatable clinical entity

BACKGROUND

Cytomegalovirus (CMV) is a common pathogen affecting the gastrointestinal tract in patients with AIDS. We report a case of CMV-induced pseudotumor of the duodenum in a patient with AIDS and review other reported cases of CMV-induced pseudotumors in the gastrointestinal tract. CMV-induced pseudotumor in patients with AIDS is an exceptionally rare clinical entity, and to our knowledge no reports have previously summarized this clinical entity.

METHODS

All previous cases included in our literature review were found using a PubMed search (1980-November 2008) of the English-language medical literature applying the terms 'CMV infection', 'inflammatory mass', 'pseudotumor', and 'gastrointestinal tract'. The references cited in these articles were examined to identify additional reports.

RESULTS

Although CMV-induced duodenitis has been described in patients with HIV infection, to our knowledge CMV-induced pseudotumor of the duodenum has not been previously reported in the literature. We describe the first case of an AIDS patient with CMV pseudotumor responding to oral treatment with valganciclovir with complete resolution of the CMV mass. Among reports of non-duodenal pseudotumor reported in the English literature, we found only 14 cases of CMV-induced gastrointestinal pseudotumors in HIV-positive patients. The clinical manifestations, pathologic findings of the CMV pseudotumors, as well as the treatment and outcome of these HIV patients are reviewed.

CONCLUSION

CMV pseudotumor should be included in the differential diagnosis of gastrointestinal mass lesions in AIDS patients and in other immunocompromised patients. The tumor often responds to antiviral therapy, but resolution of a CMV mass as a result of oral antiviral therapy has not been previously described. Since pseudotumors secondary to CMV often respond to medical treatment, it is important that the physicians treating severely immunocompromised patients are aware of this entity.

Role of upper endoscopy in diagnosing opportunistic infections in human immunodeficiency virus-infected patients

Highly active antiretroviral therapy (HAART) has dramatically decreased opportunistic infections (OIs) in human immunodeficiency virus (HIV)-infected patients. However, gastrointestinal disease continues to account for a high proportion of presenting symptoms in these patients. Gastrointestinal symptoms in treated patients who respond to therapy are more likely to the result of drug-induced complications than OI. Endoscopic evaluation of the gastrointestinal tract remains a cornerstone of diagnosis, especially in patients with advanced immunodeficiency, who are at risk for OI. The peripheral blood CD4 lymphocyte count helps to predict the risk of an OI, with the highest risk seen in HIV-infected patients with low CD4 count (< 200 cells/mm³). This review provides an update of the role of endoscopy in diagnosing OI in the upper gastrointestinal tract in HIV-infected patients in the era of HAART.

Necrotizing epiglottitis in an infant: an unusual first presentation of human immunodeficiency virus infection

We describe the case of a 4-month-old infant presenting with severe respiratory distress secondary to necrotizing epiglottitis, who was subsequently diagnosed with human immunodeficiency virus infection. Additionally, we review the existing literature on this rare condition with a focus on the potential underlying pathogenesis.

Manifestations of human cytomegalovirus infection: proposed mechanisms of acute and chronic disease

Infections with human cytomegalovirus (HCMV) are a major cause of morbidity and mortality in humans with acquired or developmental deficits in innate and adaptive immunity. In the normal immunocompetent host, symptoms rarely accompany acute infections, although prolonged virus shedding is frequent. Virus persistence is established in all infected individuals and appears to be maintained by both a chronic productive infections as well as latency with restricted viral gene expression. The contributions of the each of these mechanisms to the persistence of this virus in the individual is unknown but frequent virus shedding into the saliva and genitourinary tract likely accounts for the near universal incidence of infection in most populations in the world. The pathogenesis of disease associated with acute HCMV infection is most readily attributable to lytic virus replication and end organ damage either secondary to virus replication and cell death or from host immunological responses that target virus-infected cells. Antiviral agents limit the severity of disease associated with acute HCMV infections, suggesting a requirement for virus replication in clinical syndromes associated with acute infection. End organ disease secondary to unchecked virus replication can be observed in infants infected in utero, allograft recipients receiving potent immunosuppressive agents, and patients with HIV infections that exhibit a loss of adaptive immune function. In contrast, diseases associated with chronic or persistent infections appear in normal individuals and in the allografts of the transplant recipient. The manifestations of these infections appear related to chronic inflammation, but it is unclear if poorly controlled virus replication is necessary for the different phenotypic expressions of disease that are reported in these patients. Although the relationship between HCMV infection and chronic allograft rejection is well known, the mechanisms that account for the role of this virus in graft loss are not well understood. However, the capacity of this virus to persist in the midst of intense inflammation suggests that its persistence could serve as a trigger for the induction of host-vs-graft responses or alternatively host responses to HCMV could contribute to the inflammatory milieu characteristic of chronic allograft rejection.

Cytomegalovirus cell tropism

The human cytomegalovirus (HCMV) can infect a remarkably broad cell range within its host, including parenchymal cells and connective tissue cells of virtually any organ and various hematopoietic cell types. Epithelial cells, endothelial cells, fibroblasts and smooth muscle cells are the predominant targets for virus replication. The pathogenesis of acute HCMV infections is greatly influenced by this broad target cell range. Infection of epithelial cells presumably contributes to inter-host transmission. Infection of endothelial cells and hematopoietic cells facilitates systemic spread within the host. Infection of ubiquitous cell types such as fibroblasts and smooth muscle cells provides the platform for efficient proliferation of the virus. The tropism for endothelial cells, macrophages and dendritic cells varies greatly among different HCMV strains, mostly dependent on alterations within the UL128-131 gene locus. In line with the classification of the respective proteins as structural components of the viral envelope, interstrain differences concerning the infectivity in endothelial cells and macrophages are regulated on the level of viral entry.

A low prevalence of H pylori and endoscopic findings in HIV-positive Chinese patients with gastrointestinal symptoms

AIM: To compare the prevalence of H pylori infection, peptic ulcer, cytomegalovirus (CMV) infection and Candida esophagitis in human immunodeficiency virus (HIV)-positive and HIV-negative patients, and evaluate the impact of CD4 lymphocyte on H pylori and opportunistic infections.

METHODS: A total of 151 patients (122 HIV-positive and 29 HIV-negative) with gastrointestinal symptoms were examined by upper endoscopy and biopsy. Samples were assessed to determine the prevalence of H pylori infection, CMV, candida esophagitis and histologic chronic gastritis.

RESULTS: The prevalence of H pylori was less common in HIV-positive patients (22.1%) than in HIV-negative controls (44.8%; P < 0.05), and the prevalence of H pylori displayed a direct correlation with CD4 count stratification in HIV-positive patients. In comparison with HIV-negative group, HIV-positive patients had a lower incidence of peptic ulcer (20.7% vs 4.1%; P < 0.01), but a higher prevalence of chronic atrophy gastritis (6.9% vs 24.6%; P < 0.05)，Candida esophagitis and CMV infection. Unlike HIV-negative group, H pylori infection had a close relationship to chronic active gastritis (P < 0.05). In HIV-positive patients, chronic active gastritis was not significantly different between those with H pylori infection and those without.

CONCLUSION: The lower prevalence of H pylori infection and peptic ulcer in HIV-positive patients with gastrointestinal symptoms suggests a different mechanism of peptic ulcerogenesis and a different role of H pylori infection in chronic active gastritis and peptic ulcer. The pathogen of chronic active gastritis in HIV-positive patients may be different from the general population that is closely related to H pylori infection.

Congenital cytomegalovirus infection after recurrent infection: case reports and review of the literature

Cytomegalovirus (CMV) is one of the most common causes of congenital infections in developed countries with reported incidences varying between 0.15% and 2.0%. The effects of congenital CMV infection may vary from a congenital syndrome to an asymptomatic course. Infants that are asymptomatic at birth may still present handicaps at a later age. It is generally accepted that symptoms of congenitally infected children are more severe after primary infection than after recurrent infection. In this article, we present two case reports which demonstrate that the outcome of recurrent maternal CMV infection may be severe. In the first case, early pregnancy serology showed positive IgG and IgM, but negative IgA, whereas at the time of diagnosed fetal death, 5 weeks later, there was only positive IgG. The second case showed positive IgG and negative IgM and IgA both in early pregnancy and after delivery. Since in both cases CMV was isolated from several organs, these findings are compatible with recurrent rather than primary CMV infection. In the reported patients, fetal death and necrotising enterocolitis occurred after a congenital CMV infection, with mothers having pre-existing immunity to CMV. In conclusion, these case reports and review of the literature emphasise that the outcome of recurrent maternal CMV infection may be severe and that congenital CMV infection should be considered in cases of pregnancy loss and necrotising enterocolitis with recurrent maternal CMV infection.

Intraventricular haemorrhage in a fetus with cerebral cytomegalovirus infection

Cytomegalovirus (CMV) is the leading infectious cause of prenatal neurological damage, which is particularly severe when primary maternal infection occurs during the first 16 weeks of gestation, at the time of organ development and neuronal migration. Vascular involvement has been suggested to be among the possible pathogenic mechanisms of virus-induced pathology, in addition to direct viral effects. We report on a fetus with cerebral CMV infection, which had intraventricular haemorrhage, together with oligohydramnios and hyperechogenic bowel, following maternal primary CMV infection.

Diagnosis and treatment of esophagitis in AIDS

At least 30% of patients with AIDS experience esophageal symptoms at some point during the course of HIV infection. The aim of this review is to provide a practical approach to the evaluation and therapy of esophagitis in AIDS.

Cytomegalovirus hemorrhagic gastritis

A 36-year-old male with acquired immune deficiency syndrome (AIDS) presented with intractable nausea and vomiting of 1 week's duration that was not attributable to his medications. An esophagogastroduodenoscopy showed hemorrhagic and necrotic gastric mucosa but no ulcers were found. Histopathology revealed viral inclusions consistent with cytomegalovirus (CMV) disease of the stomach. The patient received 6 weeks of intravenous ganciclovir with resolution of symptoms and endoscopic findings. Cytomegaloviral involvement of the stomach is rare, even in immunocompromised patients. Characteristic findings on upper endoscopy are punched-out gastric ulcers. This is a rare case of CMV disease of the stomach presenting as hemorrhagic, necrotic gastritis with inflammatory bridging.

Enteric viruses in HIV-related diarrhoea

HIV-related diarrhoea is an important cause of morbidity and mortality in HIV infection. Cytomegalovirus is a well-established cause of diarrhoea, but the role of other enteric viruses is less clear and will be discussed here. The clinical manifestations, disease mechanisms, diagnostic techniques and current treatments for the management of these infections are reviewed.

Immunohistochemical studies of productive rhesus cytomegalovirus infection in rhesus monkeys (Macaca mulatta) infected with simian immunodeficiency virus

In humans infected with the human immunodeficiency virus (HIV), clinical disease due to human cytomegalovirus (HCMV) infection is one of the AIDS-defining diseases; HCMV is the most common opportunistic infection found postmortem. Histologically, the typical lesions are characterized by "owl's eye cells." In rhesus monkeys infected with simian immunodeficiency virus (SIV), comparable lesions are caused by an infection with the rhesus CMV (RhCMV). The aim of this study was to investigate the incidence of productive and latent RhCMV infection in monkeys infected with SIV macaques (SIVmac). Eleven SIVmac-infected rhesus monkeys, which were euthanatized after developing AIDS-like disease, and 11 clinically healthy and uninfected animals comprised the study. The monkeys were screened serologically for RhCMV by western-blot analysis. Immunohistochemistry was performed by an indirect immunoperoxidase technique with a polyclonal rabbit RhCMV-antiserum. Lesions characteristic of RhCMV-associated diseases were detected histologically. All animals were latently RhCMV-infected. Seven of eleven (63.6%) SIV-infected macaques were productively RhCMV infected according to immunohistochemistry. RhCMV antigen was identified in the gastrointestinal tract, the hepatobiliary system, the lungs, and the testicles. Two of these seven animals showed characteristic inflammatory lesions associated with productive infection. Consequently, the CMV prevalence in SIVmac-infected rhesus monkeys and human AIDS patients is comparable.

The modified Steiner stain: a new use for an old stain? Staining cytomegalovirus-infected cells in gastrointestinal biopsies

The modified Steiner stain is a non-specific silver stain for identifying bacteria in formalin-fixed, paraffin-embedded tissues. The principle behind its use is that bacteria are first sensitized using uranyl nitrate solution, making them able to precipitate silver from a silver nitrate solution. It is used routinely for staining gastric biopsies to identify Helicobacter pylori. Upon staining a gastric biopsy from a patient with acquired immunodeficiency syndrome (AIDS) and cytomegalovirus gastritis, we recognized that this technique also stains the viral inclusions of cytomegalovirus-infected cells. We then proceeded to stain 43 consecutive cytomegalovirus-positive gastrointestinal biopsies from 33 immunocompromised patients based on positive cytomegalovirus immunohistochemistry (DAKO-cytomegalovirus monoclonal antibody, clones DDG9 and CCH2). We also stained eight cytomegalovirus-infected, non-gastrointestinal tissues, including lung, adrenal gland, ovary, skin and neural tissue, to ensure that the stain was staining the cytomegalovirus-infected cells and not argyrophilic or argentaffin neuroendocrine cells of the gastrointestinal tract. In 40 of the 43 cytomegalovirus-infected gastrointestinal biopsies, we saw positive staining with the modified Steiner stain (93% sensitivity). The cytomegalovirus-infected, non-gastrointestinal tissues all stained positively with the modified Steiner stain. Because the modified Steiner stain is frequently used to identify Helicobacter pylori in gastric biopsies, we propose that it be studied further for possible use either as a screen or as a confirmatory tool, or both, for cytomegalovirus inclusions in gastrointestinal biopsies.

Treatment of cytomegalovirus esophagitis in patients with acquired immune deficiency syndrome: a randomized controlled study of foscarnet versus ganciclovir. The Italian Cytomegalovirus Study Group

OBJECTIVE

Although several uncontrolled studies have shown that the response rate to ganciclovir and foscarnet for all forms of cytomegalovirus (CMV) infection in immunocompromised patients is almost similar, to date, no controlled clinical trial has been specifically designed to compare these two agents in the treatment of CMV esophagitis. The aim of this study was, therefore, to compare the efficacy and safety of these two drugs in the induction therapy of CMV esophagitis in patients with acquired immunodeficiency syndrome (AIDS).

METHODS

Thirty-nine of 211 (18%) consecutive AIDS patients undergoing endoscopy for esophageal symptoms had macroscopic esophagitis that proved to be sustained by CMV based on the documentation of typical intranuclear inclusions at histology; 23 were considered eligible for this study and were randomized to receive foscarnet 90 mg/kg b.i.d. or ganciclovir 5 mg/kg b.i.d. for 21 days. Twelve patients received foscarnet, whereas 11 were treated with ganciclovir. Clinical and laboratory evaluation was performed weekly, and endoscopy was repeated at the end of therapy. The two treatment groups were well balanced as to the following characteristics at entry: age, sex, absolute number of CD4 cells, duration of AIDS, Karnofsky score, frequency of concomitant Candida esophagitis (grade I or II), and severity of esophageal symptoms.

RESULTS

Marked endoscopic improvement (complete disappearance of macroscopic lesions or significant reduction of the endoscopic score) was observed in eight of 11 (73%) of foscarnet and seven of 10 (70%) of ganciclovir-treated patients, and inclusion bodies disappeared from follow-up biopsies in 55% and 50% of patients, respectively. The symptomatic response was also similar for both treatments: 82% of patients who received foscarnet and 80% of those treated with ganciclovir had a complete or at least a good clinical response. Frequency of adverse events was comparable with both drugs: only one patient in each group suspended treatment because of severe side effects.

CONCLUSIONS

Foscarnet and ganciclovir appear to be similarly effective and safe in the induction therapy of AIDS-related CMV esophagitis. Consequently, the choice of the anti-CMV agent should be tailored to the individual patient according to the different toxicity profiles of the two drugs.

Multiple organ involvement during experimental cytomegalovirus infection is associated with disseminated vascular pathology

Since much of the pathogenesis of cytomegalovirus (CMV) disease is still unknown and vascular involvement may be of importance a rat model was used to study the nature and course of CMV-induced vascular pathology. In this model, local CMV infection was established by subcutaneous inoculation of rat-specific CMV (RCMV) in the sole of the foot. Sings of endothelial activation, including leucocyte adhesion, preceded detectable RCMV infection of these cells. ultimately, vasculitis and thrombotic occlusion were accompanied by diffuse tissue inflammation and necrosis. Generalized RCMV infection was induced in rats by intraperitoneal administration of the virus, which resulted in multiple organ pathology, including haemorrhages, inflammation, and gastrointestinal ulceration. RCMV-encoded antigens were found especially in mononuclear inflammatory cells in the organs and peripheral blood. In addition, multiple haemorrhages and disturbed haematological parameters indicated diffuse intravascular coagulopathy. In conclusion, this study provides evidence for extensive vascular involvement and haematological consequences during disseminated CMV infection. The nature and chronology of RCM-induced pathological vascular events were demonstrated, indicating the importance of endothelial damage. These data and further study may lead to a better understanding of the pathogenesis of CMV multiple-organ disease.

Detection of human Betaherpesvirinae in saliva and urine from immunocompromised and immunocompetent subjects

Human cytomegalovirus (HCMV) is a well-known opportunistic agent that reactivates in human immunodeficiency virus (HIV)-seropositive subjects. Human herpesvirus 6 (HHV-6) and HHV-7 were discovered recently and, like HCMV, belong to the Betaherpesvirinae subfamily. We looked for the presence of HCMV, HHV-6, and HHV-7 by PCR with saliva and urine samples from 125 HIV-seropositive patients at different stages of HIV infection and with saliva and urine samples from 29 HIV-seronegative subjects. All three viruses were frequently detected in the saliva (overall rates of detection, 61, 43, and 63% for HCMV, HHV-6, and HHV-7, respectively) with no correlation with the stage of immune deficiency. In contrast, HCMV was detected in urine much more frequently than the two other herpesviruses (overall rates of detection, 37, 2, and 6.5% for HCMV, HHV-6, and HHV-7, respectively) and was associated with immune deficiency. This suggests that these three genetically related viruses differ from each other with regard to replication in the urinary tract.

Quantitative systemic and local evaluation of the antiviral effect of ganciclovir and foscarnet induction treatment on human cytomegalovirus gastrointestinal disease of patients with AIDS. Italian Foscarnet GID Study Group

In a group of 29 AIDS patients with biopsy-proven human cytomegalovirus (HCMV) gastrointestinal disease (GID), HCMV GID was shown to correlate mostly with systemic HCMV infection. The antiviral induction treatment (IT) with either ganciclovir (GCV) or foscarnet (PFA) caused a significant reduction in the level of HCMV antigenemia, viremia and leukoDNAemia, and a complete virus clearance or a sharp drop of viral load in the blood of 13/13 patients and in the gastrointestinal (GI) mucosa of 12/13 (92%) patients in the GCV arm, and in the blood of 13/14 (93%) patients and in the GI mucosa of 10/12 (83%) patients in the PFA arm of the study, respectively. Similarly, the clinical response was good in 13/15 (87%) patients in the GCV arm and in 13/14 (93%) patients in the PFA arm. In addition, the finding that 2/6 patients positive for HCMV isolated from both GI mucosa and blood prior to IT were still positive in the GI tract after IT, suggested that IT could be prolonged to clear the virus from GI tract. In conclusion, both GCV and PFA showed a remarkable systemic and local antiviral effect in the treatment of HCMV GID in AIDS patients.

Ileal perforation caused by congenital or perinatal cytomegalovirus infection

Enteritis developed in a 42-day-old female infant, and during hospitalization ileal perforation occurred unexpectedly. Serologic data, urinary viral culture, and pathologic studies of the resected ileal segment all suggested cytomegalovirus infection. Gastrointestinal involvement in congenital or perinatal infection with this virus may be relatively more common than previously recognized.

Investigation of chronic diarrhoea in acquired immunodeficiency syndrome. A prospective study of 155 patients

BACKGROUND AND AIMS

The optimum diagnostic investigation for patients with acquired immunodeficiency syndrome (AIDS) and diarrhoea is not known. Often no pathogen is detected and it is unclear whether this is because pathogens are absent in some patients or the investigations used fail to detect them. The hypothesis that AIDS related diarrhoea is usually due to an infection, which can be identified by a simple diagnostic strategy based on the results of intensive investigation of a cohort of such patients, was investigated.

METHODS

155 patients with AIDS and chronic diarrhoea underwent contemporaneous examination of stools, duodenal, jejunal, and rectal biopsy specimens and duodenal aspirate for bacterial, protozoal, and viral pathogens. A decision tree analysis was used to determine the best sequential diagnostic strategy for clinicians.

RESULTS

128 of 155 patients investigated (83%) had at least one potential pathogen. The presenting clinical features could not predict the presence or site of the pathogens. Stool analysis identified the most pathogens (93 of 199, 47%). Rectal biopsy was essential for the diagnosis of cytomegalovirus and adenovirus. Duodenal biopsy was as helpful as jejunal biopsy and detected some treatable pathogens missed by other methods. Electron microscopy, impression smears, and duodenal aspirate yielded little extra information. If gut biopsy was reserved for patients without a stool pathogen, some treatable pathogens would have been missed.

CONCLUSION

Most patients with AIDS and chronic diarrhoea have at least one gut pathogen, which can be identified by stool analysis and light microscopic examination of duodenal and rectal biopsies. Some pathogens will be missed unless all these investigations are done on all such patients.

Prospective evaluation of biopsy number for the diagnosis of viral esophagitis in patients with HIV infection and esophageal ulcer

BACKGROUND

Establishing a diagnosis of viral esophagitis in patients with human immunodeficiency virus (HIV) infection has important clinical relevance. However, the number of biopsies required to diagnose viral esophagitis is currently unknown.

METHODS

Over a 34-month period, all HIV-infected patients with esophageal ulcer underwent 10 biopsies of the largest and/or most accessible lesion, primarily from the ulcer base. The first 3 specimens were placed in one formalin container, the second 3 in another, and 4 additional specimens in the third. Standard histopathologic methods were employed, as well as in situ hybridization or immunohistochemical studies in most patients, and viral cytopathic effect was defined using previously proposed criteria. Patients were then treated on the basis of the results of the initial biopsy specimens with both clinical and endoscopic follow-up.

RESULTS

One hundred HIV-infected patients with esophageal ulcer were studied. Cytomegalovirus (CMV) was considered etiologic in 50 patients. Of these 50 patients, the first three biopsy specimens were sufficient to diagnosis CMV in 40 (80%). In 5 patients (10%), the first two sets were negative with only the third set of biopsies positive. Similarly, of the 4 patients with simultaneous CMV and herpes simplex virus (HSV) esophagitis, three sets of biopsy specimens were required for diagnosis of both agents in 3 patients. HSV esophagitis alone was found in 2 patients; diagnostic viral inclusions were present in the first 3 biopsies in each patient. Thirty-five patients had HIV-associated idiopathic esophageal ulcer; only one of these patients was misdiagnosed.

CONCLUSIONS

At least 10 biopsies may be required to exclude viral esophagitis in HIV-infected patients. If biopsy specimens are adequate and no evidence of viral cytopathic effect has been found, the patient may be treated on the basis of the results of the initial clinical, endoscopic, and pathologic findings with close clinical follow-up rather than repeat endoscopy.

Gastrointestinal manifestations

Gastrointestinal disease is a common problem in the setting of HIV-1 infection. As patients live longer and other opportunistic pathogens are suppressed, these problems are becoming even more important in the quality of life.

Faecal alpha 1 antitrypsin as a marker of gastrointestinal disease in HIV antibody positive individuals

Hypoalbuminaemia and diarrhoea are common complications of HIV infection and substantial causes of morbidity, but the specific intestinal pathologies that cause enteric protein loss have not been clearly defined. Two hundred and twenty stool samples from patients with a variety of HIV related conditions were analysed for faecal alpha 1 antitrypsin. Patients with intestinal Kaposi's sarcoma had a significantly raised faecal alpha 1 antitrypsin value and hypoalbuminaemia. A faecal alpha 1 antitrypsin value of greater than 0.3 mg/g wet stool has a sensitivity of 94% and a specificity of 76% for the diagnosis of intestinal Kaposi's sarcoma in HIV positive individuals. Patients with cytomegalovirus and bacterial enteritis had raised faecal alpha 1 antitrypsin values but levels were normal for all other intestinal pathologies compared with pathogen negative stool. The combination of faecal alpha 1 antitrypsin concentration greater than 0.2 mg/g, a negative stool culture for enteric bacteria, and the absence of palatal Kaposi's sarcoma has a sensitivity of 55% and specificity of 88% for the diagnosis of enteric cytomegalovirus infection.

In situ detection of human cytomegalovirus DNA in gastrointestinal biopsies from AIDS patients by means of various PCR-derived methods

The development of new in situ assessment of HCMV disease on endoscopical gastrointestinal biopsies from AIDS patients is described and compared with the viral load measured by semiquantitative solution-phase PCR (SQ-PCR). Ten biopsies were examined by viral isolation, standard histology, in situ hybridization (ISH), in situ PCR-hybridization (PCR-ISH) and SQ-PCR, using the same target sequence. The methods developed for in situ HCMV detection were HCMV primers, the plasmid pCMV 406-S, a vector-free-digoxigenin-labelled HCMV-362 probe and the pSK + MCS nonsense probe. Paraffin-embedded MRC5 cells, either HCMV-infected or uninfected served as controls of specificity for ISH. beta-Actin primers were designed as markers of DNA integrity. Computerized models of the PCR, solution-phase and in situ PCR on formalin-fixed DNA indicated that HCMV and beta-actin primers were efficient and specific. Nine biopsies were negative for HCMV by histology and virus isolation. SQ-PCR revealed 80,000; 80 and < 80 HCMV genomic equivalents in 6, 2 and 2 biopsies, respectively. In 8 biopsies, both ISH and PCR-ISH identified positive nuclei in the intestinal epithelium, with sparing of the lamina propria. This indicates that an improvement in in situ methods can help the timely diagnosis of HCMV infection. Direct in situ PCR with beta-actin primers showed a positive signal in all the nuclei in the tissue sections, whereas omission of Taq polymerase resulted in an absence of signal, implying optimal in situ PCR. The data suggest an early-stage reactivation of HCMV, possibly harboured in the intestinal epithelium.

A colonic mass lesion due to cytomegalovirus in an immunocompromised patient

Cytomegalovirus (CMV) infection is a common cause of gastrointestinal pathology in immunocompromised patients. We report a CMV-associated mass lesion of the colon, an unusual manifestation. We review the literature and suggest a possible therapeutic approach.

Cell types involved in replication and distribution of human cytomegalovirus

As the number of patients suffering from severe HCMV infections has steadily increased, there is a growing need to understand the molecular mechanisms by which the virus causes disease. The factors that control infection at one time and the events leading to virus multiplication at another time are only beginning to be understood. The interaction of HCMV with different host cells is one key for elucidating these processes. Through modern techniques, much has been learned about the biology of HCMV infections in culture systems. In addition to endothelial cells, epithelial cells, and smooth muscle cells, fibroblasts are one cell population preferentially infected in solid tissues in vivo. From these sites of multiplication, the virus may be carried by peripheral monocytes and circulating endothelial cells to reach distant sites of the body. This would explain the multiorgan involvement in acute HCMV infection and the modes of viral transmission. From what has been learned mainly from human fibroblast culture systems, future studies will focus on how HCMV regulates the expression of its putative 200 genes in different host cells at different stages of cell differentiation and activation to result in viral latency and pathogenesis.