The histopathology of 103 consecutive colonoscopy biopsies from 82 symptomatic patients with acquired immunodeficiency syndrome: original and look-back diagnoses

A Rare Cause of Diarrhea: Intestinal Spirochetosis in an HIV-Positive Patient

Intestinal spirochetosis (IS) is a rare gastrointestinal infection with vague presenting symptoms. Diagnosis is confirmed histopathologically. Risk factors include homosexuality and HIV. Antibiotic treatment with metronidazole usually leads to resolution of symptoms. We present the case of a 56-year-old HIV-positive man with chronic, watery diarrhea who was diagnosed with IS. This case highlights the importance of considering IS in the differential in HIV-positive patients with nonspecific gastrointestinal symptoms after more common etiologies have been ruled out.

Acute Hemorrhagic Rectal Ulcer Complicated by Cytomegalovirus Enteritis following Steroid Pulse Therapy for Acute Exacerbation of Interstitial Pneumonia

We herein report a rare case of acute hemorrhagic rectal ulcer (AHRU) complicated by cytomegalovirus enteritis following steroid pulse therapy for interstitial pneumonia. An 86-year-old woman underwent steroid pulse therapy for interstitial pneumonia. She was bedridden with dyspnea and suddenly developed melena. Colonoscopy revealed AHRU, which did not improve with conservative treatment, but did improve with ganciclovir administration for cytomegalovirus enteritis. This gastrointestinal complication has not received much attention by pulmonologists who perform steroid pulse therapy for interstitial pneumonia. Delayed treatment of this complications can be fatal. Caution should be taken when administering steroid pulse therapy to bedridden patients with interstitial pneumonia.

The Adenovirus Death Protein - a small membrane protein controls cell lysis and disease

Human adenoviruses (HAdVs) cause widespread acute and persistent infections. Infections are usually mild and controlled by humoral and cell-based immunity. Reactivation of persistently infected immune cells can lead to a life-threatening disease in immunocompromised individuals, especially children and transplant recipients. To date, no effective therapy or vaccine against HAdV disease is available to the public. HAdV-C2 and C5 are the best-studied of more than 100 HAdV types. They persist in infected cells and release their progeny by host cell lysis to neighbouring cells and fluids, a process facilitated by the adenovirus death protein (ADP). ADP consists of about 100 amino acids and harbours a single membrane-spanning domain. It undergoes post-translational processing in endoplasmic reticulum and Golgi compartments, before localizing to the inner nuclear membrane. Here, we discuss the current knowledge on how ADP induces membrane rupture. Membrane rupture is essential for both progression of disease and efficacy of therapeutic viruses in clinical applications, in particular oncolytic therapy.

Cytomegalovirus enteritis with intractable diarrhea in infants from a tertiary care center in China

Background: Cytomegalovirus (CMV) is rarely thought to be the cause of significant gastrointestinal infection in immunocompetent children. CMV colitis is seldom observed in young infants. This study aims to examine the clinical features of CMV colitis in Chinese children.Methods: Patients with infantile onset CMV colitis diagnosed in intestinal tissue at Children's Hospital of Fudan University from 1st January 2017, to 31st January 2019 were enrolled. Clinical data were retrieved from medical records, and the literature on infant CMV colitis was also reviewed.Results: Ten patients were included with a median age of 2.5 months [interquartile range 2.0, 6.3 months]. All 10 patients had diarrhea, 10 patients had anemia, seven patients reported hematochezia, five patients had hypoalbuminemia, five patients had retinitis, two patients had hearing impairment, and one patient had perianal abscess and anal fistula. The patients had punched-out ulcerations, longitudinal ulcerations or irregular ulcerations on the rectum and/or colon. Typical histologic evaluation showed crypt distortion and inflammatory infiltration. CMV inclusion bodies were noted in four patients. Immunohistochemistry on intestinal tissue was performed to diagnose CMV, with all patients positive. After follow-up, all patients are clinically recovered or in remission; six patients received antiviral therapy, and five patients had healed ulcers on endoscopic examination.Conclusions: CMV colitis might be a rare cause of intractable diarrhea in immunocompetent children. Clinicians should be aware of the possibility of CMV colitis in patients with intractable diarrhea.

Histoplasma and Cytomegalovirus Coinfection of the Gastrointestinal Tract in a Patient with AIDS: A Case Report and Review of the Literature

Opportunistic infections of the gastrointestinal tract are well-documented complications of patients with acquired immunodeficiency syndrome (AIDS). However, concomitant infection by Histoplasma and cytomegalovirus has been described rarely. We present the case of an HIV patient with a CD4 count of 20 cells/uL who was admitted with odynophagia and weight loss. Endoscopic evaluation revealed ulcerations in the esophagus and colon, and a mass formation in cecum. Histology revealed budding yeasts in the cecum and a transverse colon consistent with Histoplasma. Urine Histoplasma antigen was positive. Esophageal tissue disclosed viral cytopathic changes. Immunostaining was positive for cytomegalovirus in the esophagus and transverse colon. The patient was started on appropriate antifungal and antiviral treatment with complete resolution of his symptoms. To our knowledge, this is the fifth case of Histoplasma and cytomegalovirus co-infection of the gastrointestinal tract in a patient with AIDS. We also review the literature for similar cases in regards to clinical presentation and the type of gastrointestinal involvement.

Targeting cytomegalovirus during ulcerative colitis flare-ups

Human cytomegalovirus (CMV) is a common cause of opportunistic infection leading to severe and fatal disease in immune-compromised individuals. In inflammatory bowel disease patients, particularly those with ulcerative colitis (UC), CMV is often reactivated because these patients are frequently treated with immunosuppressive agents. Many reports have described the relationship between CMV reactivation and UC exacerbation, however, a therapeutic strategy for CMV infection in UC patients has not been established. Area covered: This review highlights therapeutic strategies for UC patients with CMV infection. Recent findings have suggested a benefit from antiviral therapy in patients with histologically proven CMV colitis and/or a high colonic CMV load as determined by quantitative PCR. Expert commentary: To decide who requires antiviral therapies and when we start antiviral therapies, prospective studies of large numbers of UC patients with CMV infection are needed. However, we should know that the bottom-line therapy for UC patients with CMV infection is to optimally control mucosal inflammation.

Cytomegalovirus Colitis, Cytomegalovirus Hepatitis and Systemic Cytomegalovirus Infection: Common Features and Differences

Cytomegalovirus (CMV) is a ubiquitous human herpes virus, which, after often asymptomatic primary infection, establishes a lifelong latent infection that can periodically be reactivated in both immunocompetent and immunosuppressed carriers. Whereas the diagnostic approach in case of a suspicion of CMV reactivation is well defined, the indication for antiviral therapy can often only be made in the context of an extent of organ involvement, the immune status, and comorbidities of the patient. This article reviews the epidemiology, diagnosis, and therapy of CMV reactivation with a focus on inflammatory bowel diseases and potentially different diagnostic and therapeutic approaches in Asia and the Western world.

Symptomatic cytomegalovirus gastrointestinal infection with positive quantitative real-time PCR findings in apparently immunocompetent patients: a case series

Cytomegalovirus (CMV) gastrointestinal disease rarely occurs in immunocompetent patients, and is mainly diagnosed on the basis of histopathological findings. Real-time PCR for CMV DNA quantification is considered to be a useful diagnostic tool, but its place in the diagnostic strategy is not clearly defined. The goal of the study was to describe the clinical and paraclinical features of apparently immunocompetent patients with CMV gastrointestinal disease diagnosed according to quantitative PCR results. In this retrospective study conducted in a 1500-bed tertiary-care centre, we reviewed the case records of apparently immunocompetent patients with positive findings of CMV DNA in gastrointestinal biopsies with compatible symptoms and endoscopic findings. A total of 13 patients were included between January 2007 and December 2010. The median age was 81 years, and 54% of patients had underlying immune-modulating conditions. Diarrhoea, haematochezia and dysphagia were the main reported symptoms, and ulcers were the main endoscopic findings. The mean value of CMV DNA load in gastrointestinal biopsies was 3845 copies/μg total DNA (range, 15-15 500 copies/μg total DNA). The highest values were found in two patients who were diagnosed with adenocarcinoma in the subsequent course of CMV infection. Clinical features were similar to those in previous series in which diagnosis was based on histopathological analysis. Elderly people are more commonly affected, and a link with immune senescence is possible. Quantification of CMV DNA seems to be a useful tool for diagnosis when combined with clinical and endoscopic findings, but further studies are necessary to interpret quantitative values.

Clinicopathologic study of intestinal spirochetosis in Japan with special reference to human immunodeficiency virus infection status and species types: analysis of 5265 consecutive colorectal biopsies

Background

Previous studies reported that the incidence of intestinal spirochetosis was high in homosexual men, especially those with Human Immunodeficiency Virus infection. The aim of the present study was to clarify the clinicopathological features of intestinal spirochetosis in Japan with special reference to Human Immunodeficiency Virus infection status and species types.

Methods

A pathology database search for intestinal spirochetosis was performed at Tokyo Metropolitan Cancer and Infectious Disease Center Komagome Hospital between January 2008 and October 2011, and included 5265 consecutive colorectal biopsies from 4254 patients. After patient identification, a retrospective review of endoscopic records and clinical information was performed. All pathology slides were reviewed by two pathologists. The length of the spirochetes was measured using a digital microscope. Causative species were identified by polymerase chain reaction.

Results

Intestinal spirochetosis was diagnosed in 3 out of 55 Human Immunodeficiency Virus-positive patients (5.5%). The mean length of intestinal spirochetes was 8.5 μm (range 7–11). Brachyspira pilosicoli was detected by polymerase chain reaction in all 3 patients. Intestinal spirochetosis was also diagnosed in 73 out of 4199 Human Immunodeficiency Virus-negative patients (1.7%). The mean length of intestinal spirochetes was 3.5 μm (range 2–8). The species of intestinal spirochetosis was identified by polymerase chain reaction in 31 Human Immunodeficiency Virus-negative patients. Brachyspira aalborgi was detected in 24 cases (78%) and Brachyspira pilosicoli in 6 cases (19%). Both Brachyspira aalborgi and Brachyspira pilosicoli were detected in only one Human Immunodeficiency Virus-negative patient (3%). The mean length of Brachyspira aalborgi was 3.8 μm, while that of Brachyspira pilosicoli was 5.5 μm. The length of Brachyspira pilosicoli was significantly longer than that of Brachyspira aalborgi (p < 0.01). The lengths of intestinal spirochetes were significantly longer in Human Immunodeficiency Virus-positive patients than in Human Immunodeficiency Virus-negative patients (p < 0.05).

Conclusions

The incidence of intestinal spirochetosis was slightly higher in Human Immunodeficiency Virus-positive patients than in Human Immunodeficiency Virus-negative patients. However, no relationship was found between the Human Immunodeficiency Virus status and intestinal spirochetosis in Japan. Brachyspira pilosicoli infection may be more common in Human Immunodeficiency Virus-positive patients with intestinal spirochetosis than in Human Immunodeficiency Virus-negative patients with intestinal spirochetosis.

Gastrointestinal pathology in transplant patients

The assessment of gastrointestinal (GI) specimens from transplant patients is complicated by the wide range of potentially rare pathologies that may be found in this clinical setting. Acute GI graft-versus-host disease (GvHD) is characterized by epithelial cell apoptosis, although there is increasing recognition that acute and/or chronic inflammation may also be present. By contrast, thus far there are no histological features known to be specific to chronic GI GvHD. Mycophenolate mofetil colitis may mimic both GvHD and inflammatory bowel disease, whereas both cytomegalovirus (CMV) and adenovirus infections can cause gland apoptosis. Post-transplant lymphoproliferative disorder should be considered if a Crohn's-like histological picture is seen, and granulomas in biopsies from umbilical cord blood recipients should raise a suspicion of cord colitis syndrome. Finally, the GI tract may be involved directly or indirectly by the disease that originally required haematopoietic stem cell or liver transplantation.

Detection and quantification of EBV, HHV-6 and CMV DNA in the gastrointestinal tract of HIV-positive patients

Human herpes viruses (HHVs) have been frequently detected in the gastrointestinal (GI) tract and may contribute to the development of gastric cancer. In the present study, the detection rate and viral load of Epstein Barr virus (EBV), HHV-6 and Cytomegalovirus (CMV) were assessed in the GI tract of human immunodeficiency virus (HIV) positive patients and of uninfected patients. The analysis revealed a significantly higher detection rate of EBV and HHV-6 in HIV-infected individuals than in uninfected subjects (88.5 vs 63%; p = 0.03). Moreover, EBV DNA load was significantly higher in the stomach of HIV patients than in controls. These data suggest that the HIV infection status may increase the persistence of these viruses in the GI compartment. Intriguingly, CMV DNA was undetectable in all biopsy specimens analyzed.

Akt pathway protein expression in gastrointestinal Kaposi sarcomas: relevance for tumor biology

Gastrointestinal Kaposi sarcoma (KS) is classical, but rare. The AKT signaling pathway plays a central role in G protein-coupled receptor, key protein of KS histogenesis, encoded by KSHV/HHV8. There is increasing evidence that rapamycin, acting on AKT pathway, may be useful in the treatment of KS, including in HIV patients. We aimed to study the expression pattern of AKT pathway proteins in gastrointestinal KS. Expression of AKT, 4EBP1, PTEN, mTOR was assessed in 19 gastrointestinal KS biopsies by immunohistochemistry (17 patients). Protein expression in tumor spindle cells and in intratumor stromal vascular endothelial cells was analyzed with regard to clinicomorphological features. Tumor AKT related to lack of marked extravasated erythrocytes, tumor PTEN to presence of intratumor hemosiderin (p = 0.04 for both comparisons). Presence of both extravasated erythrocytes and hemosiderin related directly to endothelial stromal vascular nuclear PTEN and to low endothelial mTOR (p = 0.4 and 0.03, respectively). High tumor 4EBP1 related to a high slit-type abnormal vascular component (p = 0.04). The results of our study suggest pro-permeability or pro-angiogenic roles for 4EBP1 and PTEN and, opposite roles for AKT and mTOR in KS. Our hypotheses warrant further studies to obtain more generally applicable results.

Ulcerative colitis or Crohn's disease? Pitfalls and problems

The interpretation of colorectal biopsies taken for the initial diagnosis of chronic idiopathic inflammatory bowel disease (IBD) is challenging. Subclassification of IBD as ulcerative colitis (UC) or Crohn's disease, which may be particularly difficult, is the subject of this review. Biopsies taken at first presentation are emphasised, partly because their features have not been modified by time or treatment. Aspects of longstanding disease and of resections are also mentioned. The first part of the review comprises background considerations and a summary of histological features that are discriminant, according to published evidence, between UC and Crohn's disease in initial biopsies. Pitfalls and problems associated with making the distinction between UC and Crohn's disease are then discussed. These include: mimics of IBD; inadequate clinical details; unreliable microscopic features; absence of histological changes in early IBD; discontinuity in UC; cryptolytic granulomas; differences between paediatric and adult UC; reliance on ileal and oesophagogastroduodenal histology; and atypical features in IBD resections. Avoidance by pathologists of known pitfalls should increase the likelihood of accurate and confident subclassification of IBD, which is important for optimum medical and surgical management.

Inflammatory bowel disease biopsies: updated British Society of Gastroenterology reporting guidelines

Accurate histopathological assessment of biopsies is important for the diagnosis, subclassification, and management of chronic idiopathic inflammatory bowel disease (IBD). British Society of Gastroenterology (BSG) guidelines for the initial histopathological diagnosis of IBD were published in 1997. Changes since then include: more widespread use of full colonoscopy; greater recognition of the effects of time and treatment; improved documentation of variations in anatomical distribution; better understanding of the mimics of IBD; significant progress in clinical management; and modifications of terminology. Accordingly, an update is required. These revised guidelines aim to optimise the quality and consistency of reporting of biopsies taken for the initial diagnosis of IBD by summarising the literature and making recommendations based on the available evidence. Advice from existing clinical guidelines is also taken into account. Among the subjects discussed are: distinguishing IBD from other colitides, particularly infective colitis; subclassification of IBD (as ulcerative colitis, Crohn's disease, or IBD unclassified); the discriminant value of granulomas; aspects of disease distribution, including discontinuity in ulcerative colitis; time-related changes; differences between paediatric and adult IBD; the role of ileal and upper gastrointestinal biopsies; differential diagnoses such as diverticular colitis and diversion proctocolitis; and dysplasia. The need to correlate the histological features with clinical and endoscopic findings is emphasised. An approach to the conclusion of an IBD biopsy report based on the acronym Pattern, Activity, Interpretation, Dysplasia (PAID) is suggested. The key recommendations are listed at the end of the document.

Molecular evolution of human adenoviruses

The recent emergence of highly virulent human adenoviruses (HAdVs) with new tissue tropisms underscores the need to determine their ontogeny. Here we report complete high quality genome sequences and analyses for all the previously unsequenced HAdV serotypes (n = 20) within HAdV species D. Analysis of nucleotide sequence variability for these in conjunction with another 40 HAdV prototypes, comprising all seven HAdV species, confirmed the uniquely hypervariable regions within species. The mutation rate among HAdV-Ds was low when compared to other HAdV species. Homologous recombination was identified in at least two of five examined hypervariable regions for every virus, suggesting the evolution of HAdV-Ds has been highly dependent on homologous recombination. Patterns of alternating GC and AT rich motifs correlated well with hypervariable region recombination sites across the HAdV-D genomes, suggesting foci of DNA instability lead to formulaic patterns of homologous recombination and confer agility to adenovirus evolution.

Intestinal spirochetosis: an enigmatic disease

INTRODUCTION

Intestinal spirochetosis (IS) is a condition in which colonic and appendiceal epithelial cells are colonized by one of two anaerobic spirochetes, either the Brachyspira aalborgi or Brachyspira pilosicoli. There is much debate in the literature as to whether IS is a pathogen or a commensal inhabitant. A recent case of IS at our institution prompted a retrospective database search and review of the literature.

METHODS

A pathology database search for IS was performed at Carolinas Medical Center from 2003 through 2007. After patient identification, a retrospective review of the endoscopic record and the pathology report was performed. Pathology slides were reviewed for accuracy and special silver stains and/or immunostains were performed if needed. The following data were collected for each patient when available: age, gender, nationality, HIV status, and other co-morbid conditions when noted. We attempted to determine whether patients were treated for spirochetosis and if so, the treatment regimen used as well as the results.

RESULTS

The database search detected 29 patients with biopsies showing IS. Three patients were subsequently removed due to incorrect identification. A total of 26 patients with an average age of 45 years were reviewed. The most common symptoms were abdominal pain, diarrhea, and rectal bleeding. Most patients did not exhibit inflammatory changes despite the presence of spirochetosis. Pathologic examination revealed a relative increase in intra-epithelial lymphocytes in a subset of cases, a non-specific finding. Acute colitis or architectural distortion was not seen in any of the study cases. We were only able to obtain follow-up of two patients after treatment with metronidazole and both responded to therapy.

CONCLUSIONS

To date, our study is the largest case series that includes both endoscopic and pathologic descriptions and confirms the "bland" nature of the condition. In <20 % of our patients inflammation was present microscopically and it did not correlate well with endoscopic appearance. Symptoms reported by our patients were similar to those reported in previous studies, although our lack of endoscopic changes was different from one previous paper. There is no established standard of care for the treatment of IS and our study, reflects the enigmatic nature of IS as a disease process. In the absence of rigorous literature, physicians will need to use a logical and pragmatic approach to the evaluation and treatment of IS.

Opportunistic intestinal infections and risk of colorectal cancer among people with AIDS

Because mucosal inflammation contributes to colorectal carcinogenesis, we studied the impact of intestinal infections on risk of this malignancy among people with AIDS (PWA). Using the population-based HIV/AIDS Cancer Match, which includes approximately half of all PWA in the United States, the cancer registries ascertained colorectal cancers (ICD-O3 codes C180-C189, C199, C209, and C260). During 4-120 months after AIDS onset, risk of cancer occurring after AIDS-defining intestinal infections (considered as time-dependent exposures) was estimated with hazard ratios (HR) and 95% confidence intervals (CI) calculated by Cox regression. Analyses included cancers overall and by histology and anatomic site. After excluding 118 squamous cell rectal cancers (possible anal cancers), we analyzed 320 incident colorectal cancer cases that occurred among 471,909 PWA. Colorectal cancer risk was marginally elevated following cryptosporidiosis (HR=2.08, 95% CI=0.93-4.70, p=0.08) and mucocutaneous herpes (HR=1.69, 95% CI=0.97-2.95, p=0.07) but not with Pneumocystis pneumonia (HR=0.79, 95% CI=0.57-1.10). Cryptosporidiosis was associated with rare colon squamous cell carcinoma [N=8, HR=13, 95% CI=1.5-110] and uncommon histologies [HR=4.4, 95% CI=1.1-18, p=0.04], but it was not associated with colorectal adenocarcinoma (N=269, HR=1.3, 95% CI=0.4-3.9, p=0.70). Mucocutaneous herpes was associated with colon squamous cell carcinoma (HR=13, 95% CI=2.4-67, p=0.003) but not with colorectal adenocarcinoma (HR=1.3, 95% CI=0.6-2.6, p=0.52) or uncommon histologies (HR=2.5, 95% CI=0.8-8.2, p=0.13). Colon squamous cell carcinoma risk was significantly elevated among PWA who had cryptosporidiosis or mucocutaneous herpes. These findings might suggest that HPV or inflammation from other infection may contribute to carcinogenesis.

[Nonbacterial colitides]

Aside from bacterial infections, viral, fungal, and parasitic infections are important differential diagnoses in inflammatory disorders of the colorectum. In contrast to bacterial infections, in which the causative organism can hardly ever be detected histologically, in non bacterial infections the germs can often be verified by either histology, immunohistochemistry, or at least by molecular pathology. This manuscript will give an overview of the spectrum of pathogenic germs, the clinical symptoms, and pathological findings of the most important infections.

Lessons from a transplant patient with diarrhea, cryptosporidial infection, and possible mycophenolate mofetil-associated colitis

Diarrhea in a transplant recipient may be caused by infection, metabolic problems, or adverse drug effects. The immunosuppressive drug most frequently associated with diarrhea in transplant recipients is mycophenolate mofetil (MMF). We present the case of a patient with 2 potential explanations for diarrhea lasting several weeks, which occurred years after liver transplantation. Whereas stool samples were positive for cryptosporidia, the histopathological findings were compatible with MMF colitis. However, diarrhea resolved after treatment of cryptosporidial infection, despite continued MMF medication. This case shows that histopathological findings of MMF colitis may be misleading and do not prove that diarrhea is drug induced.

Human intestinal spirochetosis--a review

Human intestinal spirochetosis (IS) is a condition defined histologically by the presence of spirochetal microorganisms attached to the apical cell membrane of the colorectal epithelium. Intestinal spirochetes comprise a heterogeneous group of bacteria. In humans, Brachyspira aalborgi and Brachyspira pilosicoli predominate. Prevalence rates of IS are low where living standards are high, in contrast to poorly developed areas where IS is common. Homosexuals and HIV-infected individuals are at high risk of being colonized. Clinical significance in individual cases has remained unclear up to now. A review of the literature assumes that invasion of spirochetes beyond the surface epithelium may be associated with gastrointestinal symptoms which respond to antibiotic treatment (metronidazole), whereas individuals lacking this feature may be mostly asymptomatic. Of unknown reason, homosexual and HIV-positive men as well as children are more likely to be symptomatic irrespective of invasion. Rare cases of spirochetemia and multiple organ failure have been reported in critically ill patients with IS.

Long-term treatment of NZB mice with anti-CD4 results in wasting disease, lymphoid atrophy and chronic diarrhea

In this paper, we have shown that long-term treatment of NZB mice with anti-CD4 antibody results in four major pathological effects: firstly the development of a severe wasting disease; secondly lymphoid atrophy of the thymus, spleen, mesenteric lymph node and Peyers patches (PP); thirdly, severe chronic ulcerative colitis and fourthly a neutrophilia with neutrophil infiltration in the spleen, liver and mesenteric lymph nodes. At the same time, mice subjected to anti-CD4 treatment showed a reduction in the microbial diversity in ileal walls and contents, as well as in colonic contents, together with overgrowth of E. coli in the intestinal lumen and wall. In addition, there was the appearance of large numbers of spiral shaped bacteria on the mucosal surface often associated with colonic ulceration.

Quantification of cytomegalovirus DNA levels in intestinal biopsies as a diagnostic tool for CMV intestinal disease

BACKGROUND

CMV intestinal disease (CMV-ID) is a serious complication in immunocompromised patients and mainly diagnosed by clinical, endoscopic and histopathologic findings, whereas qualitative CMV-PCR in tissue samples is not recommended for diagnosis due to its low positive predictive value (PPV).

OBJECTIVES

To study the interpretation and diagnostic use of CMV-quantification by PCR in intestinal tissue biopsies to recognize CMV-ID. To develop cut-off intestinal CMV-loads attributing illness to CMV.

STUDY DESIGN

CMV-genome copies in 163 biopsies from the lower intestinal tract of immunocompromised patients were determined by quantitative real-time PCR, normalized to the cell number, and retrospectively compared to histopathological analysis, clinical findings and occurrence of CMV-antigenemia. Two cut-off intestinal CMV-loads, cut-off(histo) and cut-off(clin), were defined using histopathological or clinical criteria as gold standard, respectively.

RESULTS

CMV was detected in 32.5% of biopsies with a more than six log range of CMV-concentrations (1 x 10(-4)-1.4 x 10(2)copies/cell). Notably, biopsies with histopathologically or clinically confirmed CMV-ID had a significantly higher CMV-load (p<0.001). Cut-off(histo) and cut-off(clin) were defined at the intestinal CMV-load of 0.14 and 0.01 copies/cell, respectively, and improved the PPV. However, cut-off(histo) showed a decreased sensitivity for clinically defined CMV-ID cases. Interestingly, many patients with CMV-ID showed no concomitant CMV-antigenemia, suggesting a localized intestinal CMV-replication.

CONCLUSIONS

Quantification of CMV in intestinal biopsies is a useful diagnostic tool allowing the definition of cut-off values that can predict CMV-ID more accurate than qualitative PCR results. Further prospective studies have to clarify wether these cut-offs can improve diagnostics and treatment of CMV-ID in day-to-day clinical practice.

Chronic colitis associated with HIV infection can be related to intraepithelial infiltration of the colon by CD8+ T lymphocytes

Gastrointestinal complications in AIDS patients with diarrhoea are common clinical manifestations, frequently diagnosed by colonoscopy as non-specific colitis. We retrospectively study colon biopsies diagnosed as chronic colitis associated with HIV (CCH). Biopsies were sorted as patients with AIDS (serum CD4 <200 cell/mm3) but without any clear infectious process (n = 12) and patients without HIV infection (n = 24). There are low numbers of CD4+ T lymphocytes in lamina propria of AIDS patients, but CD8+ T populations in this area appear to be similar in all studied groups, regardless of HIV infection or laboratory evidence of a specific agent. We found the clear evidence of CD8+ T cells infiltration in colonic mucosa in HIV patients with microscopic colitis. An imbalance of lymphocyte subpopulations in the colon, both in the lamina propria and epithelium, could result in an intraepithelial CD8 infiltration, involved in the pathogenesis of CCH in AIDS patients.

Megacolon tóxico y perforación yeyunal por citomegalovirus

Cytomegalovirus (CMV) infection is a frequent disease in immunocompromised patients and can affect the gastrointestinal tract in 50% of patients, giving rise to colitis due to CMV. However, a perforated jejunum is not frequent. We present the case of an immunocompromised patient who was diagnosed with colitis due to CMV infection after bowel perforation. Outcome was favorable after surgery and antiviral treatment.

Cryptosporidiosis in Patients with Colorectal Cancer

Parasitological examination of feces was carried out for 55 patients with diagnosed colorectal cancer before chemotherapy. Except for Cryptosporidium sp., no other intestinal parasites were found in the specimens; moreover, only the patients with watery diarrhea were Cryptosporidium sp.-positive by enzyme immunoassay. Prevalence of infection in the group of patients with diarrhea (23 persons) was 43.5%, whereas it was 18% for the entire group of patients under study. Coproantigens of this parasite were detected primarily in the patients with tumors located on the left side (in the sigmoid and descending colon).

Symptomatic colonic spirochaetosis in an immunocompetent patient

Spirochaetes are organisms that can infect the colon of people with normal or compromised immune systems. Infected patients can present with a variety of gastrointestinal symptoms, including diarrhoea and rectal bleeding. However, some report a lack of association between specific symptoms and the presence of spirochaetes. It is therefore unclear whether the spirochaetes colonising the colon are true pathogens. Diagnosis is typically made by histological examination, with the biopsy specimen showing a band-like growth of spirochaetes adherent to the colonic luminal surface, giving an accentuated brush-border appearance. A course of metronidazole can eliminate the spirochaetes, but treatment might not lead to improvement of symptoms. Owing to the lack of a definite association between symptoms and the presence of spirochaetes, observation without specific antibiotic treatment can be pursued in most patients.

"Diversion" colitis caused by Clostridium difficile infection: report of a case

Recurrent ulcerative colitis and/or diversion colitis occur commonly in the rectal remnant after colectomy for ulcerative colitis. We report a case in which such a patient's symptoms of rectal discharge were initially thought to be the result of one or both of these diagnoses, on both clinical and histologic grounds. However, examination of the discharge revealed Clostridium difficile infection. Treatment with metronidazole suppositories improved his symptoms and avoided further inappropriate intervention.

Double-blind pilot study of mesalamine vs. placebo for treatment of chronic diarrhea and nonspecific colitis in immunocompetent HIV patients

Chronic diarrhea and colitis are common in patients positive for human immunodeficiency virus (HIV) under highly active antiretroviral treatment (HAART). This prospective double-blind study explores the effect of mesalamine vs. placebo in HIV-positive patients. Thirteen HIV-infected patients with noninfectious chronic diarrhea and > 250 CD4+ cells/mm(3) were randomized to mesalamine (2.4 g/day; n = 9) or placebo (n = 4) for 6 weeks. Colonoscopy was performed at baseline and week 6, and biopsies were obtained to calculate the Biopsy Activity Index (BAI). Diarrhea was assessed at baseline and end of treatment using the Disease Activity Index (DAI). Patients and clinicians completed Patient Global Improvement index (PGI) and Clinical Global Improvement index (CGI) at weeks 2 and 6. Comparisons at week 6 were statistically significant between mesalamine and placebo groups for BAI (P = 0.03), DAI (P = 0.007), PGI (P = 0.008), and CGI (P = 0.008). Furthermore, major improvements were documented in the mesalamine group at week 6 compared to baseline for all variables, whereas the placebo group did not have any. Mesalamine was effective for treatment of chronic diarrhea and moderate nonspecific colitis in HIV patients.

Multinucleated epithelial giant cells in colorectal polyps: a potential mimic of viropathic and/or dysplastic changes

Multinucleated epithelial giant cells (MEG) simulating viral cytopathic effect and/or dysplasia have been reported in the esophagus in association with inflammation, but the occurrence of similar cells in the colon has not been documented. Twenty-three colon specimens (22 biopsies and 1 partial colectomy) featuring MEG from 21 patients were evaluated for a variety of histologic features and correlated with clinical, endoscopic, and follow-up data. Patients included 9 males and 12 females (mean age, 64.9 years; range, 45-86 years). Eleven cases were obtained from 10 asymptomatic patients undergoing surveillance biopsies. Presenting symptoms in the remaining patients were dyspepsia, anemia, abdominal pain, and hematochezia. Over half (13 of 23) of the specimens were from descending and rectosigmoid colon, and almost all were visualized as polyps on endoscopy. Microscopically, all but 1 of the cases featured multiple MEG (range, 6 to >50 cells per biopsy) in the base and mid crypt zones of inflamed polyps with serrated architecture. Immunohistochemical stains for CMV, HSV, adenovirus, EBV, and polyoma virus were negative and no viral particles were identified on ultrastructural examination. Nuclear staining for hMLH1 and hMSH2, markers of microsatellite instability, was similar in distribution to adjacent serrated crypts, but reduced staining intensity was noted in occasional multinucleated cells. Expression of Ki-67 and cleaved caspase 3 was consistent with a quiescent or low proliferative state. Clinical follow-up was available for 9 patients (mean duration, 22.7 months). One patient died of heart failure; all others were well at last follow-up. Bizarre MEG may occasionally be seen within the crypts of inflamed polyps with serrated architecture, raising concern for dysplasia or viral infection. Immunohistochemical and ultrastructural studies fail to establish a viral etiology, and follow-up does not indicate clinically aggressive disease. These changes appear to represent a nonspecific, possibly degenerative response to inflammation and injury, and should be distinguished from dysplasia.

Quantification of adenovirus in the lower respiratory tract of patients without clinical adenovirus-related respiratory disease

Adenovirus in bronchoalveolar lavage fluid samples from 50 patients without adenovirus-related illness was quantified. In 49 patients, adenovirus was found (median load, 3.3 x 10(3) copies/microg of DNA). The adenovirus load was inversely related to lymphocyte count (Pearson correlation coefficient r = -0.311; P = .03) and was significantly greater in immunosuppressed patients than in immunocompetent patients (5.1 x 10(3) vs. 2.0 x 10(3) copies/microg of DNA; P = .028).

Intestinal spirochetosis and colon diverticulosis

A case of intestinal spirochetosis in a 62-year-old white male is reported. The condition was characterized by chronic flatulence and episodes of intestinal hemorrhage, in addition to the evidence of hypotonic diverticular disease, with a large number of slender organisms in the colon epithelium and cryptae. Spirochetes were demonstrated by Whartin-Starry stain. The serologic tests for syphilis and HIV were positive. Spirochetosis was treated with penicillin G, and the patient remains free of intestinal complaints 20 months later.

A case of severe CMV-colitis in an HIV positive patient despite moderate immunodeficiency

CMV-colitis is rare in HIV positive patients with CD4 counts higher than 100 microl(-1). We report a patient who was suffering from extensive CMV-colitis despite modest immune defect. The diagnosis was confirmed by repeated biopsies. The patient experienced an unusually long recovery which was only achieved after initiation of HAART.

The impact of adenovirus infection on the immunocompromised host

Adenovirus (Ad) infections in immunocompromised hosts have increased in frequency as the number of patients with transplants of bone marrow, liver, kidney, heart and other organs increase in number and survive longer. The numbers of such patients have also increased because of the emergence of the HIV epidemic. Ad infections with the 51 different serotypes recognised to date have few pathognomonic signs and symptoms, and thus require a variety of laboratory-based procedures to confirm infection. These viruses have the ability to target various organs with relative serotype specificity and can cause diverse manifestations including serious life-threatening diseases characteristic of the organs involved. Ads have cytolytic and immunoregulatory properties. The clinical dilemma remains the prompt recognition of Ad-related disease, the differentiation of Ad infection from Ad disease and the differentiation from other causative agents. Since the armamentarium of effective antiviral agents available to treat Ads is unproven by controlled trials and the virus is often not acquired de novo, it is difficult to prevent reactivation in immunodeficient hosts or new acquisition from donor organs. Timely discontinuation of immunosuppressive agents is necessary to prevent morbid outcomes. The clinical diseases, diagnostic tests, antiviral agents and biological aspects of the Ads as pathogens in immunocompromised patients are discussed in the context of this review. Some of the newer diagnostic tests are based on the well-studied molecular biology of Ads, which also have been attenuated by selective viral DNA deletions for use as vectors in numerous gene therapy trials in humans.

Gastrointestinal infections in the immunocompromised host

Persons with HIV infection, leukemia, lymphoma, solid organ and bone marrow transplants, and inherited immune deficiencies as well as those on immunosuppressive drugs are at high risk for infections of the gastrointestinal tract. Pathogenic as well as opportunistic viruses, bacteria, fungi, and protozoa cause infections in the esophagus, stomach, small intestine, and large intestine. Symptoms may be mild but more often are severe and even life threatening. This article reviews what is new in the field of gastrointestinal infections in the immunocompromised host during the past year. I will place specific emphasis on articles that are most pertinent to clinical care.

The role of sigmoidoscopy and colonoscopy in the diagnosis and management of lower gastrointestinal disorders: technique, indications, and contraindications

Flexible sigmoidoscopy and colonoscopy have revolutionized the clinical management of colonic diseases. Colonoscopy has a broad range of indications, including evaluating lower GI symptoms such as lower GI bleeding, evaluating abnormal radiographic findings, and screening and surveillance for colon cancer. Colonoscopy is increasingly being used therapeutically. Patient evaluation, patient instructions, and colonic preparation before colonoscopy are essential for safe and efficient colonoscopy. Intravenous sedation reduces patient pain and anxiety during colonoscopy, but requires monitoring by pulse oximetry and automated measurements of vital signs. An experienced colonoscopist can complete colonoscopy in 90% or more of cases, using maneuvers to maintain the colonic lumen in view, straighten the colonoscope, and avoid looping during colonic intubation.