Positive Toxoplasma IgG Serology Is Associated with Increased Overall Mortality - A Propensity Score-Matched Analysis.

Toxoplasma gondii is a prevalent parasitic disease with significant morbidity and mortality in immunocompromised populations. We lack long-term outcomes for latent infections. We aimed to elucidate the relationship between latent T. gondii infection and mortality risk. We queried TriNetX, a international multicenter network, to validate mortality risk differences among patients with positive or negative toxoplasma IgG through propensity score matching (PSM). We excluded patients with toxoplasmosis disease by International Classification of Diseases codes or polymerase chain reaction testing. We found 28,138 patients with available toxoplasma IgG serology. Seropositive patients were older and had a male preponderance. More seropositive patients identified as Hispanic, Latino, or Black persons. Patients who were positive for T. gondii IgG serology were slightly more likely to have underlying heart failure, a transplanted organ or tissue, malignant neoplasms of lymphoid or hematopoietic tissues, and diseases of the nervous system than seronegative controls. After PSM of patients with positive (N = 6,475) and negative (N = 6,475) toxoplasma IgG serologies, toxoplasmosis-positive patients were more likely to have long-term drug use but less likely to suffer from behavioral disorders. The overall PSM 1- and 5-year mortality was higher among patients with a positive toxoplasma IgG serology. The risk of schizophrenia was increased at 5 years. We found a prevalence of toxoplasma IgG positivity of 0.03% during the last 3 years. Latent T. gondii associates with a higher overall mortality risk. The study of social determinants of health and follow-up studies are necessary to corroborate the findings and find possible causal mechanisms.

Diabetes Mellitus Type 2 as a Risk Factor and Outcome Modifier for Cryptococcosis in HIV Negative, Non-transplant Patients, a Propensity Score Match Analysis.

Cryptococcosis is an opportunistic fungal infection of worldwide distribution with significant associated morbidity and mortality. HIV, organ transplantation, malignancy, cirrhosis, sarcoidosis, and immunosuppressive medications are established risk factors for cryptococcosis. Type 2 diabetes mellitus (DM2) has been hypothesized as a risk factor and an outcome modifier for cryptococcosis. We aimed to compare outcomes among HIV-negative, non-transplant (NHNT) patients with and without DM2. We queried a global research network to identify NHNT patients (n = 3280). We performed a propensity score-matched (PSM) analysis comparing clinical outcomes among cryptococcosis patients by DM status. We also characterize adults with cryptococcosis and DM2 as the only risk factor. After PSM, NHNT patients with DM2 were more likely to develop cognitive dysfunction [9% vs. 6%, OR 1.6; 95% CI (1.1-2.3); P = 0.01] but had similar mortality, hospitalization, ICU, and stroke risk after acquiring cryptococcosis when compared to NHNT patients without DM2. Pulmonary cryptococcosis was the most common site of infection. Among 44 cryptococcosis patients with DM2 as the only identifiable risk factor for disease, the annual incidence of cryptococcosis was 0.001%, with a prevalence of 0.002%. DM2 is associated with increased cognitive dysfunction risk in NHNT patients with cryptococcosis. It is rare for DM2 to be the only identified risk factor for developing cryptococcosis. Kidney disease, hyperglycemia, and immune dysfunction can increase the risk of cryptococcosis in patients with DM2.

Characteristics and Outcomes of Cryptococcosis among Patients with and without COVID-19.

The effect of COVID-19 on the risk and prognosis of cryptococcosis is unclear. We compared the characteristics and outcomes of cryptococcosis in patients with and without COVID-19. Patients 18 years and older with cryptococcosis were identified from TriNetX and separated into two cohorts based on a diagnosis of COVID-19 within 3 months of the index diagnosis of cryptococcosis. Differences examined between groups included comorbidities, immunosuppressive medications, ED visits, hospitalizations, ICU admissions, mechanical ventilation, and deaths. The propensity score matching was performed based on demographics and comorbidities. Of the 6998 patients with cryptococcosis included, 4.4% (n = 306) had COVID-19 prior to cryptococcosis. Mortality was higher in patients with COVID-19 compared to those without COVID-19 (14% vs. 11%, p = 0.032). Additionally, those with COVID-19 were older (55.2 ± 14.4 vs. 51.9 ± 15.2 years, p < 0.001) with higher rates of transplant (29% vs. 13%, p < 0.001), neoplastic disease (37% vs. 21%, p < 0.001), chronic kidney disease (42% vs. 18%, p < 0.001), or diabetes (35% vs. 19%, p < 0.001) but not HIV (30% vs. 31%, p = 0.618). Glucocorticoid use was more common in those with COVID-19 (52% vs. 27%, p < 0.001). More patients with COVID-19 required ED visits (29% vs. 23%, p = 0.025) and ICU admission (18% vs. 11%, p < 0.001). After propensity score matching, patients with COVID-19 had higher rates of neoplastic disease, heart failure, chronic kidney disease, and glucocorticoid use but did not experience worse outcomes compared to those without COVID-19. Patients with COVID-19 who developed cryptococcosis had independently higher rates of comorbidities and glucocorticoid use but similar outcomes, including death, versus those without COVID-19.

Seasonal variations and risk factors of Streptococcus pyogenes infection: a multicenter research network study.

Background: Streptococcus pyogenes, or Group A Streptococcus (GAS), causes acute pharyngitis and necrotizing fasciitis. Seasonal variations in GAS infections are not robustly characterized. We assessed seasonal variations and risk factors of GAS pharyngitis and ICD-10-diagnosed necrotizing fasciitis. Methods: From the period 2010-2019, we conducted a case-control study using laboratory-confirmed cases of GAS pharyngitis and a descriptive observational study of necrotizing fasciitis using ICD-10 codes. Data were collected from TriNetX, a federated research network. We extracted seasonal (quarterly) incidence rates. We used an autoregressive integrated moving average (ARIMA) model to assess seasonal variations. Demographic characteristics and 1-month outcomes were compared among adults with or without GAS pharyngitis. Results: We identified 224,471 adults with GAS pharyngitis (test-positive) and 546,142 adults without it (test-negative). GAS pharyngitis adults were younger (25.3 versus 30.2 years of age, p < 0.0001), more likely to be Hispanic individuals (10% versus 8%, p < 0.0001) and slightly more likely to be Black or African American individuals (14% versus 13%, p < 0.0001). Propensity score matching found that adults with test-positive cases of GAS pharyngitis had a higher risk of acute rheumatic fever while having no significant differences in risk of intensive care unit admission and mortality compared with test-negative cases. GAS pharyngitis average incidence peaked in the winter while dipping in the summer (0.32 versus 0.18 and 4.07 versus 1.78 per 1000 adults and pediatric patients, respectively). Necrotizing fasciitis diagnoses were highest during summer (0.032 per 1000 adults). There was a significant ARIMA seasonal variation in the time series analysis for adult and pediatric GAS pharyngitis (p < 0.0001 and p = 0.014, respectively). Necrotizing fasciitis diagnosis was not associated with seasonal variation (p = 0.861). Conclusion: Peaks in GAS pharyngitis occur in the winter months. ICD code-based necrotizing fasciitis did not show a quarterly seasonal variation.

Cryptococcosis among hospitalised patients with COVID-19: A multicentre research network study.

It is unclear if there is an association between COVID-19 and cryptococcosis. Therefore, this study aimed to describe the clinical features, risk factors, and outcomes associated with cryptococcosis in hospitalised patients with COVID-19. The objectives of this study were to determine the incidence of and examine factors associated with cryptococcosis after a diagnosis of COVID-19. We used TriNetX to identify and sort patients 18 years and older hospitalised with COVID-19 into two cohorts based on the presence or absence of a diagnosis of cryptococcosis following diagnosis of COVID-19. Outcomes of interest included the incidence of cryptococcosis following the diagnosis of COVID-19 as well as the proportion of patients in each group who had underlying comorbidities, received immunomodulatory therapy, required ICU admission or mechanical ventilation (MV), or died. Propensity score matching was used to adjust for confounding. Among 212,479 hospitalised patients with COVID-19, 65 developed cryptococcosis. The incidence of cryptococcosis following COVID-19 was 0.022%. Patients with cryptococcosis were more likely to be male and have underlying comorbidities. Among cases, 32% were people with HIV. Patients with cryptococcosis were more likely to have received tocilizumab (p < .0001) or baricitinib (p < .0001), but not dexamethasone (p = .0840). ICU admission (38% vs 29%), MV (23% vs 11%), and mortality (36% vs 14%) were significantly higher among patients with cryptococcosis. Mortality remained elevated after adjusted propensity score matching. Cryptococcosis occurred most often in hospitalised patients with COVID-19 who had traditional risk factors, comparable to findings in patients without COVID-19. Cryptococcosis was associated with increased ICU admission, MV, and mortality.

Hepatitis C Treatment Knowledge and Practice Among Family Medicine Physicians in Wisconsin During the Current Hepatitis C Epidemic.

BACKGROUND: Curative treatment for hepatitis C virus (HCV) exists, making elimination of HCV possible. However, most people with HCV have not received treatment. One barrier is limited access to treatment providers. HCV treatment can be effectively provided by primary care providers and, since 2017, Wisconsin Medicaid allows nonspecialists to prescribe treatment. We surveyed family medicine physicians in Wisconsin to evaluate capacity for the provision of HCV treatment. METHODS: We mailed a survey to family medicine physicians in Wisconsin from June 25, 2018 through September 7, 2018. Physicians were asked whether they prescribe HCV treatment and about their knowledge regarding HCV treatment and relevant statewide Medicaid policy. Using multivariable logistic regression, we evaluated physician characteristics associated with prescribing HCV treatment. RESULTS: Of 1,333 physicians surveyed, 600 (45%) responded. Few respondents reported prescribing HCV treatment independently (1%; n = 4) or in consultation with a specialist (6%; n = 35). Only 6% (n = 36) reported having a "great deal" of knowledge about HCV treatment. Most (86%; n = 515) were not aware that family medicine physicians can now prescribe HCV treatment covered by Medicaid. Physicians who practiced in offices affiliated with health systems were less likely to prescribe HCV treatment than physicians who practiced in an independent office or a Rural Health Clinic. CONCLUSIONS: Among family medicine physicians in Wisconsin, experience with and knowledge of HCV treatment was limited. Developing knowledge and skills among primary care providers is needed to expand treatment access and make progress toward HCV elimination. Studies are needed to evaluate treatment access in primary care offices affiliated with health systems.

Impact of Strand Number on Parallel ß-Sheet Stability.

We have examined whether parallel ß-sheet secondary structure becomes more stable as the number of ß-strands increases, via comparisons among peptides designed to adopt two- or three-stranded parallel ß-sheet conformations in aqueous solution. Our three-strand design is the first experimental model of a triple-stranded parallel ß-sheet. Analysis of the designed peptides by nuclear magnetic resonance (NMR) and circular dichroism (CD) spectroscopy supports the hypothesis that increasing the number of ß-strands, from two to three, increases the stability of the parallel ß-sheet. We present the first experimental evidence for cooperativity in the folding of a triple-stranded parallel ß-sheet, and we show how minimal model systems may enable experimental documentation of characteristic properties, such as CD spectra, of parallel ß-sheets.

Fluorogenic affinity label for the facile, rapid imaging of proteins in live cells.

Haloalkane dehalogenase (HD) catalyzes the hydrolysis of haloalkanes via a covalent enzyme-substrate intermediate. Fusing a target protein to an HD variant that cannot hydrolyze the intermediate enables labeling of the target protein with a haloalkane in cellulo. The utility of extant probes is hampered, however, by background fluorescence as well as limited membrane permeability. Here, we report on the synthesis and use of a fluorogenic affinity label that, after unmasking by an intracellular esterase, labels an HD variant in cellulo. Labeling is rapid and specific, as expected from the reliance upon enzymic catalysts and the high membrane permeance of the probe both before and after unmasking. Most notably, even high concentrations of the fluorogenic affinity label cause minimal background fluorescence without a need to wash the cells. We envision that such fluorogenic affinity labels, which enlist catalysis by two cellular enzymes, will find utility in pulse-chase experiments, high-content screening, and numerous other protocols.

Increasing the potency of a cytotoxin with an arginine graft.

Variants and homologs of bovine pancreatic ribonuclease (RNase A) can exhibit cytotoxic activity. This toxicity relies on cellular internalization of the enzyme. Residues Glu49 and Asp53 form an anionic patch on the surface of RNase A. We find that replacing these two residues with arginine does not affect catalytic activity or affinity for the cytosolic ribonuclease inhibitor (RI) protein. This 'arginine graft' does, however, increase toxicity towards human cancer cells. Appending a nonaarginine domain to this cationic variant results in an additional increase in cytotoxicity, providing one of the most cytotoxic known variants of RNase A. These findings correlate the potency of a ribonuclease with its deliverance of ribonucleolytic activity to the cytosol, and indicate a rational means to enhance the efficacy of ribonucleases and other cytotoxic proteins.