ECHO (Extension for Community Healthcare Outcomes) Autism STAT: A Diagnostic Accuracy Study of Community-Based Primary Care Diagnosis of Autism Spectrum Disorder

OBJECTIVE

Children can be reliably diagnosed with autism spectrum disorder (ASD) by a highly trained clinician as early as 12 to 24 months of age, but recent estimates indicate that the average age of diagnosis is 4.4 years. We hypothesized that trained primary care physicians and practitioners can reliably and accurately diagnose children 14 to 48 months with unambiguous symptoms of ASD.

METHODS

Through this diagnostic accuracy study, 20 patients diagnosed with ASD by clinicians trained through the ECHO (Extension for Community Healthcare Outcomes) Autism STAT program participated in an independent gold-standard evaluation at a regional autism center. Caregiver perceptions of the diagnostic process were also assessed.

RESULTS

Of the 20 patients who received a diagnosis of ASD by a trained clinician and completed the study, 19 diagnoses were confirmed by a gold-standard evaluation. Caregivers indicated that undergoing diagnosis in their local community rather than an autism specialty center was helpful (4.8/5 on a 5-point Likert scale, n = 19). Results of this study demonstrate that primary care clinicians can be trained to reliably diagnose ASD in children 14 to 48 months with unambiguous symptoms.

CONCLUSION

Diagnosis in the primary care setting may lead to earlier diagnosis and quicker connection to evidence-based therapies and interventions. Given the potential impact of increasing access to high-quality diagnostic services, the role of primary care clinicians in the diagnosis of ASD should be further evaluated.

Digital Methodology for Mobile Clinical Decision Support Development in Long-Term Care

The global COVID-19 pandemic has driven innovations in methods to sustain initiatives for the design, development, evaluation, and implementation of clinical support technology in long-term care settings while removing risk of infection for residents, family members, health care workers, researchers and technical professionals. We adapted traditional design and evaluation methodology for a mobile clinical decision support app - designated Mobile Application Information System for Integrated Evidence ("MAISIE") - to a completely digital design methodology that removes in-person contacts between the research team, developer, and nursing home staff and residents. We have successfully maintained project continuity for MAISIE app development with only minor challenges while working remotely. This digital design methodology can be implemented in projects where software can be installed without in-person technical support and remote work is feasible. Team skills, experience, and relationships are key considerations for adapting to digital environments and maintaining project momentum.

2B4, the natural killer and T cell immunoglobulin superfamily surface protein, is a ligand for CD48

2B4 is a cell surface glycoprotein related to CD2 and implicated in the regulation of natural killer and T lymphocyte function. A recombinant protein containing the extracellular region of mouse (m)2B4 attached to avidin-coated fluorescent beads bound to rodent cells, and binding was completely blocked by CD48 monoclonal antibodies (mAbs). Using surface plasmon resonance, we showed that purified soluble mCD48 bound m2B4 with a six- to ninefold higher affinity (Kd approximately 16 microM at 37 degreesC) than its other ligand, CD2. Human CD48 bound human 2B4 with a similar affinity (Kd approximately 8 microM). The finding of an additional ligand for CD48 provides an explanation for distinct functional effects observed on perturbing CD2 and CD48 with mAbs or by genetic manipulation.

N-acetylcysteine does not influence the activity of endothelium-derived relaxing factor in vivo

Nitric oxide forms complexes with an array of biomolecular carriers that retain biological activity. This reactivity of nitric oxide in physiological systems has led to some dispute as to whether endothelium-derived relaxing factors nitric oxide or a closely related adduct thereof, such as a nitrosothiol. In vitro bioassays used to address this question are limited by the exclusion of biological thiols that are requisite for nitrosothiol formation. Thus, the purpose of this study was to obtain insight into the identity of endothelium-derived relaxing factor in vivo. We reasoned that if endothelium-derived relaxing factor in nitric oxide, infusion of physiological concentrations of thiol would potentiate its bioactivity by analogy with effects seen in vitro, whereas nitrosothiol would be resistant to such modulation. We used venous-occlusion plethysmography to study forearm blood flow in normal subjects. Methacholine (0.3 to 10 micrograms/min) and nitroglycerin (1 to 30 micrograms/min) were infused via the brachial artery to elicit endothelium-dependent and endothelium-independent vasodilation, respectively. Dose-response determinations were made for each drug before and after an intra-arterial infusion of the reduced thiol, N-acetylcysteine, at rates estimated to achieve a physiological concentration of 1 mmol/L. Methacholine increased forearm blood flow in a dose-dependent manner. Infusion of N-acetylcysteine did not change the sensitivity (ED50, 1.7 versus 1.7 micrograms/min, P = NS) or maximal response to methacholine. In contrast, thiol increased the sensitivity to nitroglycerin (ED50, 4.7 versus 2.8 micrograms/min, P < .01). Thus, conflicting with reports in vitro, thiol does not modulate endothelium-derived relaxing factor responses in vivo. These data indicate that sulfhydryl groups are not a limiting factor for endothelium-derived relaxing factor responses in forearm resistance vessels in normal humans and are in keeping with reports that nitrosothiol contributes to endothelium-derived relaxing factor bioactivity in plasma and vascular smooth muscle. Potentiation of the effects of nitroglycerin by N-acetylcysteine can be attributed to its enhanced biotransformation to an endothelium-derived relaxing factor equivalent, such as nitrosothiol. These observations support the notion of an equilibrium between nitric oxide and nitrosothiol in biological systems that may be influenced by redox state.