Natural killer cytotoxicity in the diagnosis of immune dysfunction: criteria for a reproducible assay

Current evidence indicates that natural killer (NK) cells, which are large granular lymphocytes that mediate non-major histocompatibility complex (MHC)-restricted cytotoxicity and antibody-dependent cytotoxicity and that are involved in multiple regulatory, developmental, and immunologic processes, are important in health. Immunodeficiency states presenting with low NK activity are often associated with malignancies, chronic viral infections, or autoimmune diseases. Monitoring of NK function appears to be indicated as an aid to diagnosis, prognosis, and follow-up after therapy. Reliable performance of NK assays in a clinical laboratory requires that uniform criteria be established and followed for the acceptability of results. Statistical analysis of daily variability can be of great assistance in identifying and tracking sources of error, but routine statistical adjustments are not generally advisable. The quality control program described here provides a degree of assurance that this cytotoxicity assay can be dependable whether performed at one time point or serially. The successful implementation of this program requires laboratory resources, biostatistical support, and interpretative skills, all of which are available in a modern clinical laboratory.     

A contemporary conceptual model of hypochondriasis

Hypochondriasis (HC), which involves preoccupation with the fear of having a serious illness despite appropriate medical examination, is often encountered in medical settings. The most conspicuous feature of this disorder is seeking excessive reassurance from physicians, medical references, or self-inspection; however, many patients also fear they will receive upsetting information if evaluated and thus avoid consultations and remain preoccupied with physiologic events, believing they are physically ill. Thus, HC causes personal suffering for the patient and practical and cost management problems for professionals across fields of clinical practice. The past 2 decades have seen considerable improvement in the understanding and treatment of HC. In this article, we review a contemporary conceptual model of HC and an effective form of treatment called cognitive-behavioral therapy that is derived from this model. Recommendations for presenting this conceptualization to patients and encouraging proper treatment are also discussed.     

Attentional selectivity,automaticity, and self-efficacy predict simulator-acquired skill transfer to the clinical environment

Introduction

Several studies demonstrated that simulator-acquired skill transfer to the operating room is incomplete. Our objective was to identify trainee characteristics that predict the transfer of simulator-acquired skill to the operating room.

Bypassing proximal health care facilities for acute care: a survey of patients in a Ghanaian Accident and Emergency Centre

Objective To characterise the population that presents to the Accident and Emergency Centre (AEC) at Komfo Anokye Teaching Hospital (KATH) and to identify risk factors associated with bypassing proximal care facilities. Methods A structured questionnaire was verbally administered to patients presenting to the AEC over 2 weeks. The questionnaire focused on the use of health care resources and characteristics of current illness or injury. Measures recorded include demographics, socioeconomic status, chief complaint, transportation and mobility, reasons for choosing KATH and health care service utilisation and cost. Results The total rate of bypassing proximal care was 33.9%. On multivariate analysis, factors positively associated with bypassing included age older than 38 years (OR: 2.18, P 0.04) and prior visits to facility (OR 2.88, P 0.01). Bypassers were less likely to be insured (OR 0.31, P 0.01), to be seeking care due to injury (OR 0.42, P 0.03) and to have previously sought care for the problem (OR 0.10, P < 0.001). Conclusions Patients who bypass facilities near them to seek care at an urban AEC in Ghana do so for a combination of reasons including familiarity with the facility, chief complaint and insurance status. Understanding bypassing behaviour is important for guiding health care utilisation policy decisions and streamlining cost‐effective, appropriate access to care for all patients.