Misdiagnosis of Clostridioides difficile Infections by Standard-of-Care Specimen Collection and Testing among Hospitalized Adults, Louisville, Kentucky, USA, 2019-20201.

Although Clostridioides difficile infection (CDI) incidence is high in the United States, standard-of-care (SOC) stool collection and testing practices might result in incidence overestimation or underestimation. We conducted diarrhea surveillance among inpatients >50 years of age in Louisville, Kentucky, USA, during October 14, 2019-October 13, 2020; concurrent SOC stool collection and CDI testing occurred independently. A study CDI case was nucleic acid amplification test‒/cytotoxicity neutralization assay‒positive or nucleic acid amplification test‒positive stool in a patient with pseudomembranous colitis. Study incidence was adjusted for hospitalization share and specimen collection rate and, in a sensitivity analysis, for diarrhea cases without study testing. SOC hospitalized CDI incidence was 121/100,000 population/year; study incidence was 154/100,000 population/year and, in sensitivity analysis, 202/100,000 population/year. Of 75 SOC CDI cases, 12 (16.0%) were not study diagnosed; of 109 study CDI cases, 44 (40.4%) were not SOC diagnosed. CDI incidence estimates based on SOC CDI testing are probably underestimated.

Frequency of stool specimen collection and testing for Clostridioides difficile of hospitalized adults and long-term care facility residents with new-onset diarrhea in Louisville, Kentucky.

OBJECTIVES: This study aimed to determine the stool specimen collection and Clostridioides difficile (C. difficile) testing frequency from inpatients and long-term care facility (LTCF) residents with new-onset diarrhea. METHODS: A cross-sectional study was conducted in all wards of 9 adult hospitals (3532 beds) and 14 LTCFs (1205 beds) in Louisville, Kentucky to identify new-onset diarrhea (≥3 loose stools in the past 24 h and not present in the preceding 24 h) among Louisville adults via electronic medical record review, nurse interviews, and patient interviews during a 1-2 week observation period in 2018-2019. RESULTS: Among Louisville-resident inpatients, 167 patients with 9731 inpatient-days had new-onset diarrhea (1.7/100 inpatient-days). Stool specimens were collected from 32% (53/167); 12 (23%) specimens were laboratory-confirmed for C. difficile infection (CDI) (12.3 cases/10,000 inpatient-days). Among LTCF residents, 63 with 10,402 LTCF resident-days had new-onset diarrhea (0.6/100 LTCF resident-days). Stool specimens were collected from 32% (20/63); 9 (45%) specimens were laboratory-confirmed for CDI (8.6 cases/10,000 LTCF resident-days). CONCLUSIONS: New-onset diarrhea was common among inpatients and LTCF residents. Only one-third of patients with new-onset diarrhea had a stool specimen collected and tested for C. difficile-indicative of a potential CDI underdiagnosis-although, further studies are needed to confirm the extent of CDI underdiagnosis.

Pneumococcal epidemiology among us adults hospitalized for community-acquired pneumonia.

BACKGROUND: Few studies have measured the burden of adult pneumococcal disease after the introduction of 13-valent pneumococcal conjugate vaccine (PCV13) into the US infant vaccination schedule. Further, most data regarding pneumococcal serotypes are derived from invasive pneumococcal disease (IPD), which represents only a fraction of all adult pneumococcal disease burden. Understanding which pneumococcal serotypes cause pneumonia in adults is critical for informing current immunization policy. The objective of this study was to measure the proportion of radiographically-confirmed (CXR+) community-acquired pneumonia (CAP) caused by PCV13 serotypes in hospitalized US adults. METHODS: This observational, prospective surveillance study recruited hospitalized adults aged ≥18 years from 21 acute care hospitals across 10 geographically-dispersed cities in the United States between October 2013 and September 2016. Clinical and demographic data were collected during hospitalization. Vital status was ascertained 30 days after enrollment. Pneumococcal serotypes were detected via culture from the respiratory tract and normally-sterile sites (including blood and pleural fluid). Additionally, a novel, Luminex-based serotype-specific urinary antigen detection (UAD) assay was used to detect serotypes included in PCV13. RESULTS: Of 15,572 enrolled participants, 12,055 eligible patients with CXR+CAP were included in the final analysis population. Mean age was 64.1 years and 52.7% were aged ≥65 years. Common comorbidities included chronic obstructive pulmonary disease (43.0%) and diabetes mellitus (28.6%). PCV13 serotypes were detected in 552/12,055 (4.6%) of all patients and 265/6347 (4.2%) of those aged ≥65 years. Among patients aged 18-64 years PCV13 serotypes were detected in 3.8-5.3% of patients depending on their risk status. CONCLUSIONS: After implementation of a pneumococcal conjugate vaccination program in US children, and despite the herd protection observed in US adults, a persistent burden of PCV13-type CAP remains in this population.