Sacco KA, et al. - Researchers performed this study to investigate the factors associated with clinical outcomes in a cohort of patients with laboratory-confirmed norovirus infection. In the present cohort, the risk of hospitalization increased with the presence of an immune deficiency. Lower resolution was observed with the absence of fever that possibly may contribute to a persistent infectious state. They observed a lower overall mortality rate with the presence of concomitant C. difficile infection.

Methods

• A retrospective chart review was performed of patients with positive norovirus PCR in stool between October 1, 2015 to May 31, 2016.

Results

• During the study period, researchers identified 128 unique patients; 64 of these had immune deficiency, of which only 3 patients had a primary immune deficiency (CVID), while 61 patients had a secondary immune deficiency.
• Hospitalization was required for 50% of patients with immune deficiency, as compared to only 30% of the non-immune deficient cohort (Odds ratio: 2.1 (1.1–4.18, p=0.04).
• A polymicrobial stool infection was noticed in 32.8% of the patients and concurrent Clostridium difficile infection was observed in 21.1%.
• In the hospitalized group, initial mean total leukocyte count (WBC) was higher at 8.40 × 10⁹/L compared to 6.31 × 10⁹/L in the nonhospitalized group (p=0.049).
• Symptomatic resolution was observed in all 13 patients presenting with fever (p=0.002).
• Researchers observed a correlation of the presence of C. difficile infection with persistent symptoms (OR 2.30 [0.95–5.58], p=0.067).
• Among this cohort, the overall mortality rate was 3.13% (4 patients).
• Secondary immune deficiency was recognized in all deceased patients; none of them showed C. Difficile co-infection.