INTRODUCTION
Cytomegalovirus (CMV), a common herpes virus is a chronic stressor for the immune system
which establishes persistent, lifelong infections, and can get reactivated periodically.[1] Early CMV infection, in the immunocompetent patient is mild and remains undetected
clinically.[2] We report a patient with type 2 diabetes mellitus who developed CMV colitis presenting
as massive lower gastrointestinal bleed, which proved to be fatal. Awareness about
this life-threatening entity is important in patients who have impaired immune response.
CASE REPORT
A 50-year-old male was admitted with shock due to hematochezia for 4 days. He denied
having fever, painful defecation, abdominal pain, vomiting, hematemesis, pus, or mucus
per rectum. He was detected having diabetes 10 years ago; diabetes was poorly controlled
and was complicated by nephropathy. 2 months before presentation he developed quadriparesis
after a cerebral ischemic event, following which he was bedridden. There was no history
of gastrointestinal bleed.
Investigations at admission revealed hemoglobin of 7.1 g/dl (normal: 13.5–17), serum
creatinine 2.4 mg/dl (normal: 0.8–1.4), and serum albumin of 1.6 g/dl (normal: 3.5–5.4).
Bleeding had settled at presentation. He was resuscitated with blood transfusions
and intravenous fluids. Colonoscopy showed diffuse erythema with loss of vascular
pattern in rectum, sigmoid, and distal descending colon, with rest of the large bowel
and terminal ileum being normal [Figure 1]. Rectum also had a confluent ulcer approximately 1.5 cm in diameter [Figure 2]. Quantitative CMV DNA polymerase chain reaction (PCR) of biopsy from the ulcer base
had 128,013 copies of CMV per ml. Tissue histology did not show inclusion bodies,
it showed preserved crypt architecture and acute inflammatory infiltrate in lamina
propria. Human immunodeficiency virus enzyme-linked immunosorbent assay was negative,
and he did not receive any immune-modulatory drugs in the past. A computed tomography
angiography was not done in view of high risk of renal failure and colonoscopic findings.
Colectomy was advised but declined by the relatives in view of comorbidities and high-risk
surgery.
Figure 1: Diffuse erythema with loss of vascular pattern in sigmoid colon
Figure 2: Confluent rectal ulcer
He was treated with ganciclovir. He had another episode of massive lower gastrointestinal
bleeding after which his condition worsened. He developed shock and oliguria following
which he died.
DISCUSSION
CMV colitis has been usually described in immunocompromised hosts.[3] CMV colitis in immunocompetent patients is a rare disease and is not commonly considered
in differential diagnosis in patients who are not overtly immunocompromised.[4] However, it should be looked for in patients with bloody diarrhea, even in immunocompetent
patients in whom other causes are ruled out.[5]
CMV can cause severe toxicity in immunocompetent patients sporadically. A meta-analysis
found only 44 immunocompetent patients with CMV colitis over a period of 23 years,
14 (31.8%) of these patients died.[6] In yet another study, immunocompetent patients with CMV colitis were critically
ill, had higher mortality rate and need prolonged stay in the ICU.[7] Any part of the gastrointestinal tract, from mouth to anus can be infected by CMV,
colon is the most commonly affected while the small bowel is rarely affected.[8]
Although rare in immunocompetent individuals, CMV colitis should be suspected in individuals
with first episode of symptoms of colitis including abdominal pain, fever, diarrhea,
or lower gastrointestinal bleeding, during such an episode, presence of a condition
causing immune deficiency should be looked for and likelihood of an alternative diagnosis,
such as first presentation of inflammatory bowel disease must be excluded.[9] Diagnosis of CMV colitis is made with serologic and histologic findings. Serologic
finding includes positive IgM titer for CMV, CMV antigen in the blood and positive
PCR in blood or tissues. Histologic finding consists of intranuclear inclusion bodies,
which are pathognomic for CMV disease. In a study, PCR from colonic biopsy was found
to be most sensitive (80%) method to diagnose CMV infection followed by IgM antibody
(60%). The presence of inclusion bodies was least sensitive (10%).[10]
Our patient had diabetes and renal dysfunction, both of which are considered to modify
immune response and predispose to infections which are otherwise uncommon. In the
absence of inclusion bodies, a postmortem would have been useful to confirm the diagnosis;
however, it was not done in our patient.
We conclude that CMV colitis is an uncommon cause of lower gastrointestinal bleed.
Awareness about this potentially fatal entity is important while treating patients
who have impaired immune response.
Financial support and sponsorship
Nil.
