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Difficulty: Very hardGastroenterology and Hepatology

A 2929-year-old man is evaluated in the hospital for worsening bloody diarrhea and abdominal pain. He was admitted 55 days ago for a severe exacerbation of ulcerative pancolitis, presenting at that time with 1212 bloody bowel movements daily, severe cramps, and a weight loss of 4.5 kg4.5\text{ kg} (10 lbs10\text{ lbs}). On admission, stool studies were negative for Clostridioides difficile toxin, Salmonella, Shigella, and Campylobacter. He was subsequently started on high-dose intravenous methylprednisolone.

Despite 55 days of corticosteroid therapy, the patient's symptoms have rapidly deteriorated. He now reports 1515 bloody bowel movements a day and new-onset subjective fevers. His temperature is 38.6∘C38.6^{\circ}\text{C} (101.5∘F101.5^{\circ}\text{F}), blood pressure is 108/68 mmHg108/68\text{ mmHg}, and pulse is 114/min114/\text{min}. Physical examination reveals a distended abdomen with diffuse tenderness, but no rebound or guarding is present.

Laboratory studies show:
Hemoglobin: 7.8 g/dL7.8\text{ g/dL}
Leukocyte count: 14,500/mm314,500/\text{mm}^3
Erythrocyte sedimentation rate: 72 mm/hr72\text{ mm/hr}

An unprepared flexible sigmoidoscopy reveals diffuse mucosal erythema, friability, and several large, deep, punched-out ulcers in the descending colon. Histopathologic examination of the ulcer base biopsies demonstrates cytomegaly with prominent eosinophilic intranuclear inclusions surrounded by a clear halo.

Which of the following is the most appropriate next step in management?

  1. Initiate intravenous ganciclovirAnswer
  2. B
    Administer intravenous infliximab
  3. C
    Begin intravenous ceftriaxone and metronidazole
  4. D
    Proceed to urgent subtotal colectomy
  5. E
    Initiate oral vancomycin

Answer

The most appropriate next step is to initiate targeted antiviral therapy with intravenous ganciclovir.
The correct answer targets the definitive histologic diagnosis provided in the vignette. The presence of enlarged cells with eosinophilic intranuclear inclusions surrounded by a clear halo ('owl's eye' appearance) is pathognomonic for Cytomegalovirus (CMV). CMV colitis frequently complicates severe inflammatory bowel disease, particularly in patients receiving systemic corticosteroids or other immunosuppressants. When a patient with an IBD flare becomes refractory to steroids, superimposed infections must be ruled out. Because this patient has confirmed tissue-invasive CMV, the immediate next step in management is the initiation of antiviral therapy with intravenous ganciclovir. Tapering of corticosteroids is also typically initiated.

Step-by-Step Solution

1
Identify the primary presentation and failure of initial therapy.
The patient has a severe ulcerative colitis flare that is refractory to 5 days of high-dose intravenous corticosteroids.
Recognizing steroid refractoriness prompts the search for complications, such as superimposed infections, rather than simply assuming worsening primary inflammation.
2
Interpret the biopsy findings from the flexible sigmoidoscopy.
The biopsy shows cytomegaly and 'eosinophilic intranuclear inclusions surrounded by a clear halo' (owl's eye inclusions).
These histologic findings are pathognomonic for Cytomegalovirus (CMV) infection.
3
Synthesize the clinical picture to establish the final diagnosis.
The diagnosis is CMV colitis complicating severe, immunosuppressed ulcerative colitis.
Patients with severe IBD on immunosuppressive therapy are at high risk for reactivation of latent CMV in the colon, which masquerades as a steroid-refractory flare.
4
Determine the optimal management for the specific complication.
Select intravenous ganciclovir to treat the CMV colitis.
Treating the underlying opportunistic infection is required before considering further biologic immunosuppression or irreversible surgical resection.

Key Concept

Cytomegalovirus (CMV) colitis is a common and severe complication of steroid-refractory inflammatory bowel disease; it is diagnosed by identifying pathognomonic 'owl's eye' intranuclear inclusions on colonic biopsy and is treated with intravenous ganciclovir.
Estimated Time:2m 30s
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Topics

Gastroenterology and Hepatology

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