Zach Stednick

Epidemiology of Multiple Respiratory Viruses in Childcare Attendees

Abstract Background. The identification of multiple viruses during respiratory illness is increasing with advances in rapid molecular testing; however, the epidemiology of respiratory viral coinfections is not well known. Methods. In total, 225 childcare attendees were prospectively followed for up to 2 years. Nasal swabs were collected at respiratory illness onset and every 7–10 days until illness resolution. Swabs were tested by polymerase chain reaction for 15 respiratory viruses and subtypes. Results. At least 1 virus was detected in 382 (84%) of 455 new-onset illnesses with multiple viruses identified in 212 (46%). The proportion of subject swabs with multiple viruses detected changed as respiratory illnesses progressed from week to week, as did the prevalence of individual viruses. Children with multiple viruses detected at the time of illness onset had less frequent fever (odds ratio [OR], 0.56; 95% confidence interval [CI], 0.35, 0.90), however, these children more often had illness symptoms lasting over 7 days (OR, 1.94; 95% CI, 1.20, 3.14). Conclusions. A high proportion of daycare attendees had multiple viruses detected during respiratory illnesses. Delay between onset of illness and viral detection varied by virus, indicating that some viruses may be underrepresented in studies of virus epidemiology that rely on only a single test at symptom onset.

Evaluating risk factors for Clostridium difficile infection in adult and pediatric hematopoietic cell transplant recipients

BackgroundAlthough hematopoietic cell transplant (HCT) recipients are routinely exposed to classic risk factors for Clostridium difficile infection (CDI), few studies have assessed CDI risk in these high-risk patients, and data are especially lacking for pediatric HCT recipients. We aimed to determine incidence and risk factors for CDI in adult and pediatric allogeneic HCT recipients.MethodsCDI was defined as having diarrhea that tested positive for C. difficile via PCR, cytotoxin assay, or dual enzyme immunoassays. We included all patients who received an allogeneic HCT from 2008 to 2012 at the Fred Hutchinson Cancer Research Center; those <1 year old or with CDI within 8 weeks pre-HCT were excluded. Patients were categorized by transplanting hospital (“adult” or “pediatric”) and followed for 100 days post-HCT.ResultsOf 1182 HCT recipients, CDI was diagnosed in 17 % (33/192) of pediatric recipients for an incidence of 20 per 10,000 patient-days, and 11 % (107/990) of adult recipients for an incidence of 12 per 10,000. Pediatric recipients were diagnosed a median of 51 days (interquartile range [IQR]: 5, 72) after HCT and adults at 16 days (IQR = 5, 49). Compared with calendar year 2008, pediatric recipients transplanted in 2012 were at increased risk for CDI (hazard ratio [HR] = 3.99, p =.02). Myeloablative conditioning increased CDI risk in adult recipients (HR = 1.81, p =.005).ConclusionsPediatric and adult allogeneic recipients are at high risk of CDI post-HCT, particularly adult recipients of myeloablative conditioning. Differences in CDI incidence between children and adults may have resulted from exposure differences related to age; therefore, separately evaluating these groups should be considered in future CDI studies.

Incidence and outcomes of bloodstream infections among hematopoietic cell transplant recipients from species commonly reported to be in over-the-counter probiotic formulations

Probiotic supplementation has been promoted for numerous health conditions; however, safety in immunosuppressed patients is unknown. We evaluated bloodstream infections (BSIs) caused by common probiotic organisms in hematopoietic cell transplant recipients.

Decline in the Use of Surgical Biopsy for Diagnosis of Pulmonary Disease in Hematopoietic Cell Transplantation Recipients in an Era of Improved Diagnostics and Empirical Therapy

Abstract Historically, diagnosis of enigmatic pulmonary disease after hematopoietic cell transplantation (HCT) required lung biopsy, but recent advancements in diagnosis and therapy for respiratory infections have changed how clinicians approach pulmonary abnormalities. We examined temporal trends in the use of lung biopsy after HCT. We retrospectively reviewed patients who underwent their first allogeneic HCT at the Fred Hutchinson Cancer Research Center between the years 1993 to 1997, 2003 to 2007, and 2013 to 2015 and subsequently underwent surgical lung biopsy for any reason. Lung biopsy between cohorts were analyzed using a Cox proportional hazards model with death and relapse considered competing risks. Of 1418 patients, 52 (3.7%) underwent 54 post-HCT surgical lung biopsies during 1993 to 1997 compared with 24 (2.1%) and 25 biopsies in the 2003 to 2007 cohort; 2 cases of surgical lung biopsies out of 786 HCT recipients occurred during the 2013 to 2015 cohort (.25%). The median time to biopsy post-HCT was 71.5 days (IQR, 31 to 89) for the early cohort and 97 days (IQR, 42 to 124) for the late cohort, for an overall biopsy incidence of .15 and .075 per 1000 patient days in the first year after HCT, respectively. Patients in the 2003 to 2007 cohort were less likely to undergo a lung biopsy (adjusted HR, .50; 95% CI, .29 to .83; P = .008) when compared with patients in the early cohort, but more patients in the early cohort underwent lung biopsy without antecedent bronchoscopy (25/54 [46%] versus 3/25 [12%], P = .005). Although infections were a more common finding at biopsy in the early cohort (35/1418 versus 8/1148, P < .001), the number of biopsies demonstrating noninfectious lesions was similar between the two cohorts (19/1418 versus 17/1148, P = .76). Fungal infections were the major infectious etiology in both cohorts (32/35 [91%] versus 5/8 [63%], P = .07), but there was a significant reduction in the number of Aspergillus species found at biopsy between the cohorts (30/54 versus 1/25, P < .001). A similar percentage underwent biopsy with therapeutic intent for invasive fungal disease in the 2 cohorts (8/54 [15%] versus 4/25 [16%]). Surgical evaluation of lung disease in HCT recipients significantly declined over a span of 2 decades. The decline from the years 1993 to 1997 compared with 2003 to 2007 was because of a reduction in the number of biopsies for post-transplant infections due to aspergillosis, which is temporally related to improved diagnostic testing by minimally invasive means and the increased use of empiric therapy with extended-spectrum azoles. This practice of primary nonsurgical diagnostic and treatment approaches to pulmonary disease post-HCT have continued, shown by low numbers of surgical biopsies over the last 3 years.

Evaluation of routine pretransplantation screening for methicillin-resistant Staphylococcus aureus in hematopoietic cell transplant recipients

Methicillin-resistant Staphylococcus aureus (MRSA) screening guidelines for hematopoietic cell transplant (HCT) recipients are not well defined. Retrospective assessment of standardized pretransplantation MRSA screening in a large single-center cohort of HCT recipients demonstrated that colonization was uncommon, and that no colonized patients developed posttransplantation invasive complications.

Bacterial foodborne infections after hematopoietic cell transplantation.

Diarrhea, abdominal pain, and fever are common among patients undergoing hematopoietic cell transplantation (HCT), but such symptoms are also typical with foodborne infections. The burden of disease caused by foodborne infections in patients undergoing HCT is unknown. We sought to describe bacterial foodborne infection incidence after transplantation within a single-center population of HCT recipients. All HCT recipients who underwent transplantation from 2001 through 2011 at the Fred Hutchinson Cancer Research Center in Seattle, Washington were followed for 1 year after transplantation. Data were collected retrospectively using center databases, which include information from transplantation, on-site examinations, outside records, and collected laboratory data. Patients were considered to have a bacterial foodborne infection if Campylobacter jejuni/coli, Listeria monocytogenes, E. coli O157:H7, Salmonella species, Shigella species, Vibrio species, or Yersinia species were isolated in culture within 1 year after transplantation. Nonfoodborne infections with these agents and patients with pre-existing bacterial foodborne infection (within 30 days of transplantation) were excluded from analyses. A total of 12 of 4069 (.3%) patients developed a bacterial foodborne infection within 1 year after transplantation. Patients with infections had a median age at transplantation of 50.5 years (interquartile range [IQR], 35 to 57), and the majority were adults ≥18 years of age (9 of 12 [75%]), male gender (8 of 12 [67%]) and had allogeneic transplantation (8 of 12 [67%]). Infectious episodes occurred at an incidence rate of 1.0 per 100,000 patient-days (95% confidence interval, .5 to 1.7) and at a median of 50.5 days after transplantation (IQR, 26 to 58.5). The most frequent pathogen detected was C. jejuni/coli (5 of 12 [42%]) followed by Yersinia (3 of 12 [25%]), although Salmonella (2 of 12 [17%]) and Listeria (2 of 12 [17%]) showed equal frequencies; no cases of Shigella, Vibrio, or E. coli O157:H7 were detected. Most patients were diagnosed via stool (8 of 12 [67%]), fewer through blood (2 of 12 [17%]), 1 via both stool and blood simultaneously, and 1 through urine. Mortality due to bacterial foodborne infection was not observed during follow-up. Our large single-center study indicates that common bacterial foodborne infections were a rare complication after HCT, and the few cases that did occur resolved without complications. These data provide important baseline incidence for future studies evaluating dietary interventions for HCT patients.

Underutilization of norovirus testing in hematopoietic cell transplant recipients at a large cancer center

HighlightsTesting patterns and incidence of norovirus are analyzed in transplant recipients.Norovirus testing is infrequently used despite clear seasonal variation.Targeted educational programs to enhance norovirus testing are needed. &NA; The development of a new laboratory‐developed norovirus assay provided an opportunity to assess testing patterns, incidence, and outcomes of norovirus among hematopoietic cell transplant (HCT) recipients. Clostridium difficile and norovirus tests from 1,393 HCT recipients were compared in these analyses. In this population of high‐risk patients, norovirus appeared to occur seasonally, but testing was infrequent despite a correlation with more severe disease when compared with patients with C difficile infection.