Making Air Pollution Visible: A Tool for Promoting Environmental Health Literacy

BACKGROUND

Digital maps are instrumental in conveying information about environmental hazards geographically. For laypersons, computer-based maps can serve as tools to promote environmental health literacy about invisible traffic-related air pollution and ultrafine particles. Concentrations of these pollutants are higher near major roadways and increasingly linked to adverse health effects. Interactive computer maps provide visualizations that can allow users to build mental models of the spatial distribution of ultrafine particles in a community and learn about the risk of exposure in a geographic context.

OBJECTIVE

The objective of this work was to develop a new software tool appropriate for educating members of the Boston Chinatown community (Boston, MA, USA) about the nature and potential health risks of traffic-related air pollution. The tool, the Interactive Map of Chinatown Traffic Pollution ("Air Pollution Map" hereafter), is a prototype that can be adapted for the purpose of educating community members across a range of socioeconomic contexts.

METHODS

We built the educational visualization tool on the open source Weave software platform. We designed the tool as the centerpiece of a multimodal and intergenerational educational intervention about the health risk of traffic-related air pollution. We used a previously published fine resolution (20 m) hourly land-use regression model of ultrafine particles as the algorithm for predicting pollution levels and applied it to one neighborhood, Boston Chinatown. In designing the map, we consulted community experts to help customize the user interface to communication styles prevalent in the target community.

RESULTS

The product is a map that displays ultrafine particulate concentrations averaged across census blocks using a color gradation from white to dark red. The interactive features allow users to explore and learn how changing meteorological conditions and traffic volume influence ultrafine particle concentrations. Users can also select from multiple map layers, such as a street map or satellite view. The map legends and labels are available in both Chinese and English, and are thus accessible to immigrants and residents with proficiency in either language. The map can be either Web or desktop based.

CONCLUSIONS

The Air Pollution Map incorporates relevant language and landmarks to make complex scientific information about ultrafine particles accessible to members of the Boston Chinatown community. In future work, we will test the map in an educational intervention that features intergenerational colearning and the use of supplementary multimedia presentations.

Toxic pseudomembranous colitis in a patient with ulcerative colitis

Toxic colitis is a severe disease that may be caused by several inflammatory and/or infectious diseases. Ulcerative colitis is one of the most frequent causes of toxic colitis in the United States. Toxic megacolon complicating Clostridium difficile colitis is a rare occurrence with significant morbidity and mortality.

CASE REPORT

A 52-year-old male presented with rectal bleeding and tenesmus. He had been treated for amebiasis with metronidazole, and had improved. Two weeks later, symptoms recurred, and he was referred to our hospital. A sigmoidoscopy and biopsies demonstrated mucosal ulcerative colitis. He underwent treatment with systemic prednisone, mesalamine, and hydrocortisone enemas with adequate response. He was asymptomatic for 2 months, but later presented with a tender abdomen and rectal bleeding. Plain abdominal and thorax films showed colonic distention and free intraperitoneal air. Emergency laparotomy was performed, and an inflamed and distended colon, with free inflammatory liquid in the peritoneum, was found. A total abdominal colectomy with temporary ileostomy and Hartmann's pouch was performed. The histopathology analysis demonstrated a Clostridium difficile pseudomembranous colitis.

CONCLUSION

The presence of toxic megacolon due to Clostridium difficile in patients with ulcerative colitis is a rare complication that may be suspected in patients with initial relapse who are on antibiotics.

[Total proctocolectomy with ileo-anal reservoir in "J". Experience at the Salvador Zubirán National Institute of Nutrition]

BACKGROUND

Total proctocolectomy with ileal pouch-anal anastomosis (TPCIAA) is the procedure of choice for patients with Ulcerative Colitis and Familial Adenomatous Polyposis. The frequency of presentation of both diseases is low in Mexico, therefore the experience with the surgical procedure is limited.

OBJECTIVE

To analyze the operative morbidity and mortality and long-term functional results in a series of patients operated upon with the TPCIAA in a referral center in Mexico.

MATERIAL AND METHODS

Retrospective analysis of 44 consecutive patients operated upon from 1987 through 1997. The operation included resection of the anal transitional zone, handsewn anastomosis of a "J" pouch, and diverting ileostomy in all cases. Operative morbidity and mortality, and long-term functional results and complications were determined.

RESULTS

Mean age was 33 +/- 15 years. There were 52% women and 48% men. Diagnoses were ulcerative colitis in 59% and familial polyposis in 36%. Global morbidity was 39%, and mortality 2%. With a mean follow-up of 24 months, mean number of bowel movements was 4, 10% of patients had diurnal spotting, 30% nocturnal spotting, and no patient had gross incontinence. Three patients presented pouchitis with adequate response to antibiotics. Two patients presented long-term pouch fistulas that did not require pouch excision.

CONCLUSIONS

The TPCIAA is a feasible operation with acceptable rates of morbidity and mortality and satisfactory functional results.

[Surgical treatment of anorectal fistulas. A 17-year experience at the Instituto Nacional de la Nutrición "Salvador Zubirán"]

INTRODUCTION

Surgical treatment for anorectal fistula may be difficult because of the risk of recurrence, prolonged healing or anal incontinence following the operation.

OBJECTIVE

To analyze the experience with the surgical management of ano-rectal fistula during a period of 17 years.

PATIENTS AND METHODS

The medical records of 105 patients with anorectal fistulas were reviewed retrospectively, with analysis of demographic and clinical data, operative treatment, and results.

RESULTS

There were 73% men and 27% women. Mean age was 45 years. 86% had an underlying chronic disease, most frequently diabetes mellitus (21%) and obesity (14%). No anatomic classification of the fistulous tract was done in 86% of cases, and inter-sphincteric tracts were the most frequent type in the classified cases. In 90% of cases, treatment was fistulectomy. Complications occurred in 13% of cases, mainly delayed healing (6.5%). Recurrent disease was documented in 11 cases (10%), and the majority were treated with a new fistulectomy. There were no cases with anal incontinence following the operation.

CONCLUSIONS

The necessity of performing the anatomic classification of ano-rectal fistula should be emphasized. Fistulectomy was the most frequent surgical procedure.