Diagnostic utility of quantitative cytomegalovirus DNA polymerase chain reaction in intestinal biopsies from patients with inflammatory bowel disease

[Cytomegalovirus Infection in Patients with Inflammatory Bowel Disease]

A diagnostic evaluation for cytomegalovirus (CMV) infection is required in patients with inflammatory bowel disease (IBD) who do not respond to steroid or immunomodulatory treatment. However, there is no consensus on an accurate diagnostic method for CMV infection in patients with IBD, and it is difficult to clearly distinguish the exacerbation of ulcerative colitis from CMV colitis. According to several recent studies, the most accurate test method for CMV colitis is quantitative tissue DNA-quantitative PCR, which is recommended as the first-line diagnostic technique along with an immunohistochemistry stain. The benefit of antiviral therapy for CMV infection in patients with IBD is also controversial. Although the definition of viral load is unclear, antiviral therapy can lower the rate of colectomy in CMV infections with a high viral load in patients with IBD. This review presents the latest findings about CMV infections in IBD, based on recently reported studies.

Cytomegalovirus Colitis in Immunocompetent and Immunocompromised Children: A 2-Center Study

BACKGROUND

Data about cytomegalovirus (CMV) colitis in children are scarce. We aimed to describe the characteristics of childhood CMV colitis in terms of risk factors, clinical symptoms, diagnosis, therapeutic approaches, and outcomes.

METHODS

Inflammatory bowel disease (IBD) and non-IBD patients with CMV colitis diagnosed by histology and tissue CMV PCR at 2 tertiary centers between January 2017 and November 2019 were studied. Clinical and laboratory data were retrieved from medical records. Underlying conditions, immune status, response to therapy and outcomes were described and followed up to 6 months after diagnosis.

RESULTS

A total of 16 children (8 non-IBD, 7 ulcerative colitis and 1 Crohn's disease) with CMV colitis were included. All patients had persistent diarrhea (bloody in 13 cases). There was a significant age difference between IBD and non-IBD children (P < 0.05). The final diagnosis in 1 patient was immunodeficiency with a mutation in JAK1 gene. Three children were categorized as apparently immunocompromised and 4 children as apparently immunocompetent. Ulcer was not visible in 2 children from the non-IBD group. The mean fecal calprotectin level of IBD children was significantly higher than that of non-IBD children (376.12 ± 231.21 µg/g vs. 160.96 ± 69.94 µg/g, P < 0.05). After follow-up, 1 patient died because of another reason. Ganciclovir was used in 14 of 16 children for 3 weeks and the treatment was continued with valganciclovir in selected 6 children.

CONCLUSIONS

CMV colitis is a rare but overlooked cause of prolonged diarrhea in immunocompetent and immunocompromised children. CMV colitis might present without any ulcer formation at colonoscopy in infants.

Diagnostic significance of cytomegalovirus DNA quantitation in gastrointestinal biopsies: comparison with histopathological data and blood cytomegalovirus DNA

OBJECTIVES

This study aims to improve the diagnosis of gastrointestinal (GI) cytomegalovirus (CMV) disease. It presents the results of a novel study in which CMV blood viral load (BVL), tissue viral load (TVL) determined by PCR and hematoxylin-eosin (HE)/immunohistochemistry (IHC) results of GI biopsies are examined comparatively.

METHODS

CMV DNA was investigated by quantitative real-time PCR in blood and GI biopsy specimens of 76 patients suspected of CMV disease. Biopsies were also performed HE/IHC stainings in the pathology laboratory.

RESULTS

This study included 76 patients whose median age was 34.5 years and 58% (44) were male. Tissue CMV PCR positivity was detected in the highest colon (40/53;75.5%) samples. HE, IHC, blood and tissue CMV PCR positivity rates of all samples were 15.8, 25, 50 and 71.1%, respectively. When IHC was used as the gold standard test for ROC analysis, the optimal cutoff values for the maximum sensitivity and specificity for BVL and TVL were 1.91 log10 copies/ml and 3.82 log10 copies/mg, respectively. Sensitivity and specificity for the cutoff value of tissue CMV DNA were 78.9 and 74.3%, respectively (P < 0.001).

CONCLUSION

In this study, CMV DNA was detected in 71.1% of the tissue samples of the cases by PCR. Since the sensitivity of the histopathological examinations accepted as the gold standard is low, simultaneous with the histopathological examinations, determination of BVL, TVL and the identification of optimal cutoff values have been shown to support the diagnosis of GI CMV disease.

Standard treatment-refractory cytomegalovirus encephalitis unmasked by immune reconstitution inflammatory syndrome and successfully treated with virus-specific hyperimmune globulin

Objectives

Cytomegalovirus (CMV)‐related encephalitis is a rare but potentially life‐threatening complication of CMV infection in immunocompromised patients. The high mortality rate is associated with deficient immune system reconstitution after hematopoietic stem cell transplant (HSCT) and poor bioavailability of antiviral drugs in cerebrospinal fluid (CSF). CMV‐related central nervous system (CNS) infection may occur with aspecific symptoms, without evidence of either blood viral load or magnetic resonance imaging (MRI) signs of encephalitis.

Methods

Here, we describe a 10‐year‐old girl who underwent an allogeneic HSCT and subsequently developed CMV encephalitis. Because of the absence of CMV antigen in the blood, the diagnosis of encephalitis was proposed only after a delay, following the onset of immune reconstitution inflammatory syndrome (IRIS). Two months of combined dual antiviral therapy with ganciclovir and foscarnet proved ineffective against CMV and caused significant bone marrow and renal toxicity. To avoid further toxicity, the girl was given daily treatment with CMV‐hyperimmune globulins alone.

Results

After three weeks, the CSF viral load dropped significantly and was undetectable within three more weeks. In the meantime, the renal impairment resolved, and there was a complete bone marrow recovery.

Conclusion

We suggest that this patient succeeded in achieving CMV CSF clearance with high dose of CMV‐hyperimmune globulin, given alone, because of the ability of immunoglobulins to penetrate the blood–brain barrier (BBB).

Ulcerative Colitis and Cytomegalovirus Infection: From A to Z

Despite multiple studies, the role of cytomegalovirus [CMV] infection in exacerbating the severity of inflammation in ulcerative colitis [UC], and its response to treatment, remain debatable. Additionally, the optimal diagnostic tests for CMV infection in the setting of UC relapse, and timing of antiviral treatment initiation, remain unclear. The challenge faced by gastroenterologists is to differentiate between an acute UC flare and true CMV colitis. It seems that the presence of CMV colitis, as defined by the presence of intranuclear or intracellular inclusion bodies on haematoxylin and eosin [H&E] staining and/or positive immunohistochemistry [IHC] assay on histology, is associated with more severe colitis. Patients with CMV infection and acute severe colitis are more resistant to treatment with corticosteroids than non-infected patients. This refractoriness to steroids is related to colonic tissue CMV viral load and number of inclusion bodies [high-grade CMV infection] which may have a pronounced effect on clinical outcomes and colectomy rates. Whereas many studies showed no effect for antiviral treatment on colectomy rates in CMV-infected UC patients, there was a significant difference in colectomy rates of patients with high-grade infection who received anti-viral therapy compared with those who did not receive treatment. It was therefore proposed that high-grade CMV disease indicates that the virus is acting as a pathogen, whereas in those with low-grade CMV disease, the severity of IBD itself is more likely to influence outcome. The different algorithms that have been put forward for the management of patients with UC and concomitant CMV infection are discussed.

Cytomegalovirus and Inflammatory Bowel Diseases (IBD) with a Special Focus on the Link with Ulcerative Colitis (UC)

Cytomegalovirus (CMV) infects approximately 40% of adults in France and persists lifelong as a latent agent in different organs, including gut. A close relationship is observed between inflammation that favors viral expression and viral replication that exacerbates inflammation. In this context, CMV colitis may impact the prognosis of patients suffering from inflammatory bowel diseases (IBDs), and notably those with ulcerative colitis (UC). In UC, the mucosal inflammation and T helper cell (T_H) 2 cytokines, together with immunomodulatory drugs used for controlling flare-ups, favor viral reactivation within the gut, which, in turn, increases mucosal inflammation, impairs corticoid and immunosuppressor efficacy (the probability of steroid resistance is multiplied by more than 20 in the case of CMV colitis), and enhances the risk for colectomy. This review emphasizes the virological tools that are recommended for exploring CMV colitis during inflammatory bowel diseases (IBD) and underlines the interest of using ganciclovir for treating flare-ups associated to CMV colitis in UC patients.