Bla g 3: a novel allergen of German cockroach identified using cockroach-specific avian single-chain variable fragment antibody.

BACKGROUND: The IgE response to cockroach allergens is thought to be associated with asthma. German cockroach (GCr) allergen extract is a complex mixture of allergens, and the identification and characterization of immunodominant allergens is important for the effective diagnosis and treatment of GCr-induced asthma. OBJECTIVE: To characterize a novel GCr allergen homologous to the American cockroach allergen Per a 3. METHODS: GCr-specific avian monoclonal antibodies were used for direct immunoprecipitation of specific targets from whole-body GCr extract. Precipitated protein was identified by mass spectrometry and sequence analysis. Putative recombinant protein also was expressed, purified, and used for determination of allergenicity, determined by IgE enzyme-linked immunosorbent assay with serum from 61 GCr-allergic patients. The identified target also was analyzed for heat stability using a bead-based assay. RESULTS: The immunoprecipitated target of monoclonal antibody 2A1 was identified as a novel allergen of GCr homologous to American cockroach allergen Per a 3. This homolog, designated Bla g 3, has an apparent mass of 78 kDa, can be measured in GCr extract using antibody 2A1, and is a heat-stable protein. Screening of 61 serum samples from GCr-allergic patients showed a 22% prevalence of Bla g 3-specific IgE. CONCLUSION: Bla g 3 is a GCr allergen with structural homology to American cockroach allergen Per a 3.

Clinical characteristics of hospitalized patients with false-negative severe acute respiratory coronavirus virus 2 (SARS-CoV-2) test results.

OBJECTIVE: To determine clinical characteristics associated with false-negative severe acute respiratory coronavirus virus 2 (SARS-CoV-2) test results to help inform coronavirus disease 2019 (COVID-19) testing practices in the inpatient setting. DESIGN: A retrospective observational cohort study. SETTING: Tertiary-care facility. PATIENTS: All patients 2 years of age and older tested for SARS-CoV-2 between March 14, 2020, and April 30, 2020, who had at least 2 SARS-CoV-2 reverse-transcriptase polymerase chain reaction tests within 7 days. METHODS: The primary outcome measure was a false-negative testing episode, which we defined as an initial negative test followed by a positive test within the subsequent 7 days. Data collected included symptoms, demographics, comorbidities, vital signs, labs, and imaging studies. Logistic regression was used to model associations between clinical variables and false-negative SARS-CoV-2 test results. RESULTS: Of the 1,009 SARS-CoV-2 test results included in the analysis, 4.0% were false-negative results. In multivariable regression analysis, compared with true-negative test results, false-negative test results were associated with anosmia or ageusia (adjusted odds ratio [aOR], 8.4; 95% confidence interval [CI], 1.4-50.5; P = .02), having had a COVID-19-positive contact (aOR, 10.5; 95% CI, 4.3-25.4; P < .0001), and having an elevated lactate dehydrogenase level (aOR, 3.3; 95% CI, 1.2-9.3; P = .03). Demographics, symptom duration, other laboratory values, and abnormal chest imaging were not significantly associated with false-negative test results in our multivariable analysis. CONCLUSIONS: Clinical features can help predict which patients are more likely to have false-negative SARS-CoV-2 test results.

Universal screening for Clostridioides difficile at an urban academic medical center.

We implemented universal inpatient Clostridioides difficile screening at an 800-bed hospital. Over 3 years, 2,010 of 47,048 screening tests (4.2%) were positive, with significantly higher rates of C. difficile colonization on transplant units than medical-surgical units: 5.4% (152 of 2,801) versus 4.3% (880 of 20,564), respectively (P = .005). Compliance with screening ranged from 79% to 96%.

Three-Tiered COVID-19 Cohorting Strategy and Implications for Memory-Care.

An outbreak of SARS-CoV-2 in a skilled nursing facility (SNF) can be devastating for residents and staff. Difficulty identifying asymptomatic and presymptomatic cases and lack of vaccination or treatment options make management challenging. We created, implemented, and now present a guide to rapidly deploy point-prevalence testing and 3-tiered cohorting in an SNF to mitigate an outbreak. We outline key challenges to SNF cohorting.

Clinical Characteristics and Outcomes Among Older Women with HIV.

OBJECTIVES: To inform the development of HIV care strategies for older women with HIV infection, an understudied group, we compared the psychosocial, behavioral, and clinical characteristics of HIV-positive women aged ≥50 (older women) with those aged 18-49 (younger women). METHODS: We examined factors among HIV-positive women in care using data from the 2009 through 2013 cycles of a nationally representative sample of HIV-positive adults in care (Medical Monitoring Project). We compared psychosocial, clinical, and behavioral factors among women aged ≥50 years at interview versus those aged <50 years. We calculated weighted frequency estimates and performed logistic regression to compute adjusted prevalence ratios (aPR) and 95% confidence intervals (CIs) for the comparison of characteristics among women aged ≥50 versus <50 years. RESULTS: Of 22,145 participants, 6186 were women; 40.7% (CI 39.1-42.3) were ≥50 years, and 32.7% of older women reported being sexually active. Compared with women <50 years, women aged ≥50 years were more likely to be dose adherent (aPR = 1.19; CI 1.07-1.33), prescribed antiretroviral therapy and have sustained viral load suppression (aPR = 1.03; CI 1.00-1.18), and were less likely to report any depression (aPR = 0.92; CI 0.86-0.99), to report condomless sex with a negative or unknown partner if sexually active (aPR = 0.56; CI 0.48-0.67), and to have received HIV/sexually transmitted infection (STI) prevention counseling from a healthcare provider (aPR = 0.82; CI 0.76-0.88). CONCLUSIONS: These data suggest that older women in HIV care have more favorable outcomes in some clinical areas, but may warrant increased HIV/STI prevention counseling from their care providers, especially if sexually active.