Pulmonary Langerhans cell histiocytosis: emerging concepts in pathobiology,radiology, and clinical evolution of disease

Pulmonary Langerhans cell histiocytosis (PLCH) is an uncommon disorder of adult smokers associated with a significant morbidity. Arising from the aberrant accumulation of Langerhans and other immune cells, PLCH tends to cause a relatively isolated pulmonary involvement as compared to other forms of Langerhans cell (LC) and histiocytic disorders. Increased knowledge of cytokine triggers, dendritic cell trafficking, and clonality of LC populations in PLCH have resulted in an improved understanding of the pathobiology of PLCH. High-resolution CT (HRCT) of the chest has led to better appreciation of nodular and cystic radiographic abnormalities characteristic of the disease. Correlation of HRCT abnormalities with lung pathologic changes has led to an improved comprehension of clinical evolution of PLCH. Current clinical predictors for PLCH outcomes remain poor, although long-term follow-up and radiologic monitoring may help to define disease progression. This review discusses advances in PLCH emphasizing the etiopathologic bases of the disease and currently available radiologic modalities for monitoring disease progression.     

Therapeutic Options for the Management of Postprandial Glucose in Patients With Type 2 Diabetes on Basal Insulin

In Brief For patients with type 2 diabetes who require add-on therapy to metformin plus basal insulin, GLP-1 receptor agonists may be a favorable option because they effectively manage postprandial glucose, reduce body weight, and have an overall favorable safety profile compared to other agents. Given the wide range of treatment combinations available for type 2 diabetes management, health professionals must partner with patients to determine the best choices based on patients’ individual lifestyle, resources, and treatment goals.Providing patients with optimal strategies for the management of hyperglycemia associated with type 2 diabetes is challenging. This is especially true as type 2 diabetes progresses and patients require two- and three-drug combinations or complex insulin regimens to achieve glycemic targets (1). Current consensus guidelines from the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD), as well as the 2015 diabetes management algorithm of the American Association of Clinical Endocrinologists, recognize that many different drug combinations can be used to achieve A1C goals (Figure 1) (1,2). Given this range of available therapeutic options, ADA/EASD guidelines emphasize the importance of individualized, patient-centered care (1). If patients are able to be involved with treatment decisions, health care professionals (HCPs) must use a shared decision-making process to increase patient satisfaction and adherence to treatment (3). HCPs should emphasize treatment outcomes that are also important to the patient (3). Factors to consider in such individualized type 2 diabetes treatment plans include patients’ attitudes and willingness to make lifestyle changes and risk factors for hypoglycemia and other adverse events. HCPs should also consider patients’ body weight, duration of disease, life expectancy, comorbidities, established vascular complications, overall level of support, and economic burdens of treatment (1). All treatment plans should include strategies for controlling obesity, blood pressure, and hyperlipidemia and emphasize smoking cessation, regular exercise, and healthy eating habits (4).Open in a separate windowFIGURE 1.ADA/EASD general recommendations for type 2 diabetes management (1). DPP-4-i, DPP-4 inhibitor; Fx’s, fractures; GLP-1-RA, GLP-1 receptor agonist; HF, heart failure; SU, sulfonylurea.^aConsider beginning at this stage in patients with a very high A1C level (e.g., ≥9%).^bConsider rapid-acting, nonsulfonylurea secretagogues (meglitinides) in patients with irregular meal schedules or who develop late postprandial hypoglycemia on sulfonylureas.^cUsually a basal insulin (NPH, glargine, or detemir) in combination with noninsulin agents.^dCertain noninsulin agents may be continued with insulin. Consider beginning at this stage if patient presents with severe hyperglycemia (≥300−350 mg/dL; A1C level ≥10.0−12.0%) with or without catabolic features (e.g., weight loss or ketosis).     

A virtual pointer to support the adoption of professional vision in laparoscopic training

Purpose

To assess a virtual pointer in supporting surgical trainees’ development of professional vision in laparoscopic surgery.

Methods

We developed a virtual pointing and telestration system utilizing the Microsoft Kinect movement sensor as an overlay for any imagine system. Training with the application was compared to a standard condition, i.e., verbal instruction with un-mediated gestures, in a laparoscopic training environment. Seven trainees performed four simulated laparoscopic tasks guided by an experienced surgeon as the trainer. Trainee performance was subjectively assessed by the trainee and trainer, and objectively measured by number of errors, time to task completion, and economy of movement.

Results

No significant differences in errors and time to task completion were obtained between virtual pointer and standard conditions. Economy of movement in the non-dominant hand was significantly improved when using virtual pointer (\(p = 0.012\)). The trainers perceived a significant improvement in trainee performance in virtual pointer condition (\(p < 0.001\)), while the trainees perceived no difference. The trainers’ perception of economy of movement was similar between the two conditions in the initial three runs and became significantly improved in virtual pointer condition in the fourth run (\(p = 0.017\)).

Conclusions

Results show that the virtual pointer system improves the trainer’s perception of trainee’s performance and this is reflected in the objective performance measures in the third and fourth training runs. The benefit of a virtual pointing and telestration system may be perceived by the trainers early on in training, but this is not evident in objective trainee performance until further mastery has been attained. In addition, the performance improvement of economy of motion specifically shows that the virtual pointer improves the adoption of professional vision— improved ability to see and use laparoscopic video results in more direct instrument movement.

     

HIV Infection Among People Who Inject Drugs in the United States: Geographically Explained Variance Across Racial and Ethnic Groups

Objectives. We explored how variance in HIV infection is distributed across multiple geographical scales among people who inject drugs (PWID) in the United States, overall and within racial/ethnic groups.Methods. People who inject drugs (n = 9077) were recruited via respondent-driven sampling from 19 metropolitan statistical areas (MSAs) for the Centers for Disease Control and Prevention’s 2009 National HIV Behavioral Surveillance system. We used multilevel modeling to determine the percentage of variance in HIV infection explained by zip codes, counties, and MSAs where PWID lived, overall and for specific racial/ethnic groups.Results. Collectively, zip codes, counties, and MSAs explained 29% of variance in HIV infection. Within specific racial/ethnic groups, all 3 scales explained variance in HIV infection among non-Hispanic/Latino White PWID (4.3%, 0.2%, and 7.5%, respectively), MSAs explained variance among Hispanic/Latino PWID (10.1%), and counties explained variance among non-Hispanic/Latino Black PWID (6.9%).Conclusions. Exposure to potential determinants of HIV infection at zip codes, counties, and MSAs may vary for different racial/ethnic groups of PWID, and may reveal opportunities to identify and ameliorate intraracial inequities in exposure to determinants of HIV infection at these geographical scales.Since the mid-1990s, there has been an increase in studies evaluating whether features of the social, economic, physical, and political environment (i.e., place characteristics) affect health. This focus on place characteristics is evident in the development of theories conceptualizing place characteristics as health determinants,1–3 in the use of geospatial and systematic social observation methods to measure place characteristics,4–10 in the application of multilevel modeling to assess the potential impacts of place characteristics,11–18 and in the recognition that interventions should not solely encourage individual behavior change but also modify environmental features.3,16,19Literature emerging from this field of research demonstrates that place characteristics operationalized at different geographical scales influence psychosocial processes and individual behaviors that increase vulnerability to several health outcomes. With rare exception,20–24 however, studies of place and health typically assess the potential influence of place characteristics at a single geographical scale and do not simultaneously evaluate characteristics of other geographical scales. For example, several studies, including our own,25,26 sample participants from a single metropolitan statistical area (MSA) to assess the relationships of census tract characteristics to health, without sampling participants from multiple MSAs to simultaneously assess the relationships of tract-, county-, and MSA-level characteristics to health.25–32 The decision to focus on characteristics of a single geographical scale may arise because of data availability, cost constraints, or feasibility.Studies of place and health that focus on a single geographical scale, however, may misspecify relationships and hinder the exploration of causal pathways in 2 ways. First, studies that focus on features measured at a single geographical scale may overlook potential health determinants that are operationalized at other geographical scales. For instance, research assessing the relationships of features of neighborhoods (e.g., economic deprivation, racial/ethnic composition, policing practices, and “crackdowns”) cannot determine the influence of policies, laws, and governmental expenditures that are operationalized at county, MSA, and state levels, and shape neighborhood environments. Second, studies of features of a single geographical scale cannot determine whether relationships between characteristics operating at one geographical scale are confounded, mediated, or modified by characteristics of other geographic scales.3,16,33 The possibility that at least 1 of these mechanisms can occur has been demonstrated in research conducted by Warner and Gomez, which suggests that, among Black women diagnosed with breast cancer, residing in census blocks with high concentrations of Black residents is more protective against mortality in more racially segregated metropolitan areas than less racially segregated metropolitan areas.34In addition, research assessing the association of place-based factors with health outcomes rarely highlights the extent to which variance in health outcomes is explained by place and place-based factors. Determining whether health outcomes vary geographically can generate hypotheses about inequities in exposure to potential place-based determinants of health, and thereby inform how interventions and social policies are developed and spatially concentrated.35The present study illustrates the generative possibilities of extending research beyond a single geographical scale by achieving 2 primary aims. The study’s first aim is to determine the share of total variance in HIV infection that is apportioned to zip codes, counties, and MSAs among people who inject drugs (PWID). In the United States, PWID account for 22% of people living with HIV,36 and a growing body of literature demonstrates that features of neighborhoods such as census-tract racial composition and block-level social or physical disorder are associated with HIV-related outcomes among PWID,37,38 as are features of MSAs, including drug-related law enforcement, income inequality, residential segregation, and health service access.39–41 Revealing the geographical scale to which variance in HIV infection is apportioned among PWID can stimulate hypotheses about inequities in exposure to place-based determinants of HIV and inform the development and tailoring of place-based interventions. For example, finding high MSA-level variance in HIV infection may support analyses of whether MSA-level variations in health care service access predict variance in HIV serostatus and, if they do, support interventions to increase health care access in low-access MSAs. In contrast, if little to no variance in HIV infection among PWID is apportioned to MSAs, PWID may encounter a relatively uniform exposure to health care service access.Previous studies have found that variance in some health outcomes vary across racial/ethnic groups.42,43 The second aim of this study therefore tests the hypothesis that variance in HIV infection will differ within each of 3 racial/ethnic groups of PWID: non-Hispanic/Latino Whites, non-Hispanic/Latino Blacks, and Hispanics/Latinos.     

Utility Values Associated with Diabetic Retinopathy in Chennai,India

Abstract

Purpose: The aim of this study was to estimate utility values associated with different severity stages of diabetic retinopathy (DR) in India by a direct elicitation method (time-trade off, TTO) and indirectly by questionnaire.

Methods: People with diabetes aged 40 years and over were recruited from an on-going DR epidemiology study and a laser clinic in Chennai, India. Utility values were elicited using the direct TTO method and indirectly through a validated questionnaire (EQ-5D).

Results: Of 249 participants, 30 had no DR, 73 had non-proliferative DR, 114 had sight-threatening DR, and 32 were blind from DR (bilateral visual acuity <6/60). The mean TTO utility value was 0.73 (standard deviation, SD, 0.31). TTO utility values decreased with increasing severity of DR (p?<?0.001) and were significantly lower among participants with sight threatening DR (0.70, SD 0.33) and blindness (0.55, SD 0.24) compared to those with no DR (0.89, SD 0.25) after adjustment for sociodemographic and clinical factors. Blindness from DR was independently associated with a lower EQ-5D utility value. The utility value derived from EQ-5D (0.06) associated with being blind from DR was substantially lower than that of the TTO utility value (0.55).

Conclusions: This study provides estimates of utility values that can be used in economic evaluations of DR screening strategies in India. The relatively low utility values associated with blindness highlights the importance of screening programs for early detection of the sight-threatening stages to prevent vision loss from DR in this setting.     

Punch's use of Graphic Satire for Middle Class Scientific Engagement, 1889–1914

Punch was the foremost satirical publication of the nineteenth and early twentieth century, engaging thoughtfully and seriously with the world of science. This article examines three of Punch's graphic satires concerning medical innovation. As Punch relied heavily on topical humour, many of its satires can trace their roots to occurrences reported in the popular press, which help to put the cartoons in context for an accurate reading of Punch's motives.

Punch's method, to educate and engage its loyal readers in debates about the role of medicine and doctors whilst making them laugh, would seem to be unique.