Table 1.

Factors that increase the risk of infection in patients with solid tumors

Risk factor(s)a	Additional explanatory comments
Neutropenia	Chemotherapy, radiation therapy, bone marrow infiltration with tumor, drugs (e.g., ganciclovir)
Disruption of anatomic barriers (e.g., skin, mucosal surfaces)	Chemotherapy (mucositis), radiation therapy, vascular access catheters, urinary catheters, percutaneous endoscopic gastrostomy tubes and other medical devices, surgical/diagnostic procedures
Obstruction due to primary or metastatic tumor	Airways: post-obstructive pneumonia, lung abscess, empyema, fistula formation (e.g., broncho-pleural or trachea-esophogeal)
	Biliary tract: ascending cholangitis, hepatic and pancreatic abscess
	Bowel: bowel obstruction, necrosis, perforation, peritonitis, hemorrhage
	Urinary tract: urinary tract infection, renal abscess, prostatitis or prostatic abscess
Procedure and devices	Diagnostic/therapeutic surgery: surgical site infections, wound dehiscence, abscess formation
	Shunts: disseminated infection (bacteremia) shunt-related infections such as meningitis/ventriculitis, hepato-biliary infections, complicated urinary tract infections
	Prosthetic devices: infected prosthesis, osteomyelitis and/or septic arthritis, local abscess formation, disseminated infection
Miscellaneous factors	Age, nutritional status, prior antibiotic exposure, loss of gag reflex

^aMultiple risk factors frequently occur in the same patient