Cytomegalovirus infection of the appendix in patient with the acquired immunodeficiency syndrome

Cytomegalovirus immune reconstitution inflammatory syndrome manifesting as acute appendicitis in an HIV-infected patient

Background

Appendicitis occurs with increased frequency in HIV infected compared to HIV uninfected persons. CMV-related appendicitis specifically presents with typical appendicitis symptoms including surgical abdomen, fever and leukocytosis and may have a more severe course with higher mortality than other types of infective appendicitis. We report the first case of CMV appendicitis as a manifestation of Immune Reconstitution Inflammatory Syndrome (IRIS).

Case presentation

The patient was a 38 year old woman with a recent diagnosis of HIV infection who complained of right lower quadrant pain, anorexia, nausea and fevers two weeks after initiating antiretroviral therapy. Acute appendicitis was suspected and the patient underwent an appendectomy. Pathologic examination of the resected appendiceal tissue demonstrated inflammation with perforation and cytopathic changes typical of CMV that were positive for CMV by immunostain. This presentation of CMV abruptly after antiretroviral therapy initiation with a pronounced cellular infiltration of the tissue, is consistent with CMV-IRIS presenting as appendicitis.

Conclusions

Appendicitis can be a rare manifestation of CMV-IRIS in HIV-infected patients who start antiretroviral therapy. Evaluation of appendiceal tissue for cytopathic changes and CMV should be considered in acute appendicitis in HIV infected persons.

Outcomes of Laparoscopic and Open Appendectomy for Acute Appendicitis in Patients with Acquired Immunodeficiency Syndrome

The aims of this study were to compare outcomes of appendectomy between acquired immunodeficiency syndrome (AIDS) and nonAIDS patients and laparoscopic appendectomy (LA) versus open appendectomy (OA) in AIDS patients. Using the Nationwide Inpatient Sample database, from 2006 to 2008, clinical data of patients with AIDS who underwent LA and OA were evaluated. A total of 800 patients with AIDS underwent appendectomy during these years. Patients with AIDS had a significantly higher postoperative complication rate (22.56% vs 10.36%), longer length of stay [(LOS) 4.9 vs 2.9 days], and higher mortality (0.61% vs 0.16%) compared with non-AIDS patients. In nonperforated cases in patients with AIDS, LA was associated with a significantly lower complication rate (11.25% vs 21.61%), lower mortality (0.0% vs 2.78%), and shorter mean LOS (3.22 days vs 4.82 days) compared with OA. In perforated cases in patients with AIDS, LA had a significantly lower complication rate (27.52% vs 57.50%), and shorter mean LOS (5.92 days vs 9.67 days) compared with OA. No mortality was reported in either group. In patients with AIDS, LA has a lower morbidity, lower mortality, and shorter LOS compared with OA. Laparoscopic appendectomy should be considered as a preferred operative option for acute appendicitis in patients with AIDS.

Infectious causes of appendicitis

The pathologic spectrum of the inflamed appendix encompasses a wide range of infectious entities, some with specific histologic findings, and others with nonspecific findings that may require an extensive diagnostic evaluation. The appendix is exclusively involved in some of these disorders, and in others may be involved through extension from other areas of the gastrointestinal tract. This review discusses the pathologic features of bacterial, viral, fungal, and parasitic infections affecting the appendix, including adenovirus; cytomegalovirus; Yersinia, Actinomyces, Mycobacterium, or Histoplasma species; Enterobius vermicularis; schistosomiasis; and Strongyloides stercoralis. Pertinent ancillary diagnostic techniques and the clinical context and significance of the various infections are also discussed.

Appendicitis in HIV-infected patients during the era of highly active antiretroviral therapy

BACKGROUND

Limited studies have suggested increased incidence rates and unusual clinical presentations of appendicitis among HIV-infected patients during the pre-highly active antiretroviral therapy (HAART) era. Data in the HAART era are sparse, and no study has evaluated potential HIV-related risk factors for the development of appendicitis.

METHODS

We retrospectively studied 449 HIV-infected patients receiving care at a US Naval hospital involving 4750 person-years (PY) of follow-up. We also evaluated the rates of appendicitis among HIV-negative persons at our medical facility. We compared demographics, HIV-specific data, and HAART use in HIV-infected patients with and without appendicitis.

RESULTS

Sixteen (3.6%) of 449 patients developed appendicitis after HIV seroconversion. The incidence rate was 337 cases/100 000 PY, more than fourfold higher than among HIV-negative persons. Eighty-eight per cent of cases among HIV-infected patients had an elevated white blood count at presentation, 39% were complicated, and 64% required hospitalization. HIV-infected patients with appendicitis compared with those who did not develop appendicitis were less likely to be receiving HAART (25 vs. 71%, P<0.001), had higher viral loads (3.5 vs. 1.7 log(10) HIV-1 RNA copies/mL, P=0.005), and were younger (median age of 30 vs. 41 years, P<0.002). In the multivariate model, receipt of HAART remained protective [odds ratio (OR) 0.21, P=0.012] for appendicitis, while younger age was positively associated (OR 1.08, P=0.048) with appendicitis.

CONCLUSION

Acute appendicitis occurs at higher incidence rates among HIV-infected patients compared with the general population. Our study demonstrates that the lack of HAART may be a risk factor for appendicitis among HIV-infected patients; further studies are needed.

High prevalence of an active cytomegalovirus infection in the appendix of immunocompetent patients with acute appendicitis

BACKGROUND

Appendicitis is a very common surgical diagnosis with unclear pathology. Human cytomegalovirus (HCMV) can modulate our immune system and has been associated with inflammatory bowel disease (IBD) and various other inflammatory diseases.

METHODS

We investigated the association between HCMV and acute appendicitis in 14 immunocompetent patients. Tissue sections from 10 AIDS patients with verified HCMV infection were used as positive controls, and uninflamed intestinal tissue sections from 12 patients were used as negative controls.

RESULTS

Cells double positive for HCMV early antigens and IL-6/IL-8 were observed in the appendices of 64.3% of appendicitis patients (9 of 14) by immunohistochemical analysis. HCMV late antigen was found in the appendices of 42.9% of the acute appendicitis patients (6 of 14). Latent HCMV appendix infection, as verified by in situ hybridization, as well as HCMV IgG, was observed in 78.6% of patients (11 of 14). The study samples from all 6 healthy appendices were negative for HCMV early and late antigens, although 50% (3 of 6) were HCMV IgG and HCMV DNA positive.

CONCLUSIONS

We have shown that HCMV infection of the appendix is associated with acute appendicitis (P = 0.002) and possibly with the severity of the disease. Our study identified HCMV as a pathogen to be sought for in the appendicitis patient group, possibly allowing further medical treatment of these patients.

Appendicitis and infections of the appendix

The pathologic spectrum of the acutely inflamed appendix encompasses a wide range of infectious and noninfectious entities. The appendix suffers alone in some of these disorders, and in others may be involved through extension from other areas of the gastrointestinal tract. Although the appendix is the most commonly resected and examined intraabdominal organ, the pathogenesis and etiology of acute nonspecific appendicitis (the most common diagnosis made in this organ) remains enigmatic. This review encompasses the pathology, pathogenesis, and bacteriology of acute appendicitis, as well as controversial issues such as the diagnosis of chronic appendicitis and the significance of a morphologically unremarkable appendectomy specimen in the clinical context of appendicitis. In addition, the pathologic features, pertinent diagnostic techniques, and clinical significance of several specific bacterial, viral, fungal, and parasitic infections affecting the appendix are presented, including adenovirus, cytomegalovirus, Yersinia species, actinomycosis, Mycobacteria species, histoplasmosis, pinworms, schistosomiasis, and Strongyloides stercoralis.

Gastrointestinal pathology in HIV-infected patients

Specific pathologic processes, particularly oral, esophageal, and intestinal infections, are common in the alimentary tract of AIDS patients. Many of these diseases are adequately assessed only by biopsy with histologic examination. Most are rare or unreported in immunocompetent hosts and are easily missed by those not familiar with them. This article describes the gross or endoscopic and histologic appearances and the diagnostic criteria for enteric pathologic processes seen in HIV-infected individuals.

The right lower quadrant "revisited"

Appendicitis remains a common and morbid illness in children. The history, epidemiology, pathophysiology, clinical presentation, diagnostic evaluation, and management of acute appendicitis are discussed in this article.

Infectious diarrhoea. Viruses

Increased knowledge has been gained into the aetiology and pathogenesis of viral gastroenteritis during the past two decades. There are now thought to be four major subclassifications of gastroenteritis-causing viruses; these include rotavirus, enteric adenovirus, calicivirus, including Norwalk and Norwalk-like viruses, and astrovirus. The association of these agents with gastroenteritis has been made by their electron microscopic detection in stool and intestinal biopsy specimens from affected patients, the inability to detect the viruses after recovery from disease, and the subsequent development of immunoglobulin responses after infection; in some instances disease transmission was achieved in human volunteers. The association of these viral agents with gastroenteritis has facilitated the study of classification, epidemiology, immunity, diagnostic tests, methods of treatment and, most importantly, disease prevention strategies such as vaccine development for rotavirus. This chapter highlights the major features of these agents, with special attention being given to the pertinent molecular biology as well as current and future prospects for vaccination. Enteric viral infections of the gastrointestinal tract in patients with AIDS are also discussed.