Viral infections in inflammatory bowel disease: Tips and tricks for correct management

Table 2 Diagnostic approach to inflammatory bowel disease patients with infectious symptoms

Symptoms cluster	Potential viral pathogens	Diagnostic work up
Fever	VZV, HBV, HCV, EBV, HIV, SARS-CoV-2	Medical history, physical examination
		Blood cell counts, PCR, PCT
		VZV, HBV, HCV, EBV and HIV Ab
		Hemocultures
		Urine analysis and culture
		Stool examinations
		Strongyloidiasis serology
		Chest X-ray
		Infectious disease specialist consult
Respiratory	Influenza, SARS-CoV-2 (Bilateral interstitial infiltrates)	Chest X-ray or US
		SaO2% < range → CT
		Pneumonia:
		Sputum cultures
		NPS for SARS-CoV-2/influenza virus Legionella and pneumococcal U-Ag
		Bronchoalveolar lavage
Gastrointestinal	HSV, CMV, EBV, Adenovirus, Astrovirus, Norovirus, Rotavirus, Sapovirus	Rule out potential enteric infection:
		Stool cultures
		Examination for parasites
		C. difficile toxin testing
		Multiplex molecular assays
Central nervous system	CMV, HSV, VZV, JC virus	Neurological advice
		CSF cultures and PCR
		MRI
Cutaneous	HSV, VZV	Dermatological consult
		PCR on recent lesion

CRP: C-reactive protein; PCT: Procalcitonin; US: Ultrasound; CT: Computed tomography; NPS: Nasopharyngeal swab; U-Ag: Urinary antigen; CSF: Cerebrospinal fluid; PCR: Polymerase chain reaction; MRI: Magnetic resonance imaging; HAV: Hepatitis A virus; HBV: Hepatitis B virus; HCV: Hepatitis C virus; HPV: Human papillomavirus; HIV: Human immunodeficiency virus; HSV: Herpes simplex virus; CMV: Cytomegalovirus; VZV: Varicella zoster virus; EBV: Epstein-Barr virus; SARS-CoV-2: Severe acute respiratory syndrome coronavirus 2; JC: John Cunningham virus; C. difficile: Clostridium difficile.