Faculty Bibliography

Aim: To identify factors that affect outpatient colonoscopy attendance in a tertiary care center. Methods: A retrospective review of the electronic medical record system was performed for patients scheduled for outpatient colonoscopies from July to October 2008 at the Manhattan VA Hospital. Patient age, gender, ethnicity, marital status, gender of referring healthcare provider (HCP), distance from hospital (in miles), living situation (e.g. apartment vs. shelter, alone vs. with others), employment status, smoking history, appointment time, day of the week, month, proximity to holiday (in days), family history of gastrointestinal malignancy, prior colon procedures, indication for current procedure, comorbidities (diabetes, hypertension, hyperlipidemia, obesity, pathologies of the major organ systems, psychiatric disorders, and history of cancer) were compared. Statistical analysis using t- and +/-2-tests was performed, with p values 0.05 denoting statistical significance. Results: A total of 517 patients were identified, comprised of 358 patients who presented for their scheduled colonoscopies ("shows") and 159 patients who did not ("no shows"). Patients were more likely to attend their procedure if the referring HCP was female rather than male (p<0.001, Figure 1a). A higher percentage of employed patients presented at their scheduled time compared with patients who were not employed (p<0.005, Figure 1b). Fewer active smokers attended compared with non-smokers. A higher percentage of "shows" who quit smoking attended compared with that of "no shows" (p<0.05, Figure 1c). Patients were less likely to attend the morning time slots from 8-11:30am compared with the afternoon/ early evening time slots from 12-5:30pm (p<0.05, Figure 1d). Patients with neurological conditions (Figure 2, footnote) were less likely to show up at their scheduled appointments (p<0.05, Figure 1e). A greater percentage of "no shows" showed up for future outpatient colonoscopies at the VA Hospital compared with "shows" (p<0.00!

A 38-year-old man with a history of HIV infection virologically suppressed on antiretroviral therapy presents to his gastroenterologist for evaluation of iron deficiency anemia and weight loss. A diagnostic colonoscopy demonstrates a two-centimeter ulcerated mass in the cecum. Biopsies of the lesion return moderately differentiated adenocarcinoma that is wild type for the KRAS mutation by real-time PCR.

Understanding of the human microbiome continues to grow rapidly; however, reports on changes in the microbiome after HIV infection are still limited. This review surveys the progress made in methodology associated with microbiome studies and highlights the remaining challenges to this field. Studies have shown that commensal oral, gut, vaginal, and penile bacteria are vital to the health of the human immune system. Our studies on crosstalk among oral and gastrointestinal soluble innate factors, HIV, and microbes indicated that the oral and gut microbiome was altered in the HIV-positive samples compared to the negative controls. The importance of understanding the bacterial component of HIV/AIDS, and likelihood of "crosstalk" between viral and bacterial pathogens, will help in understanding the role of the microbiome in HIV-infected individuals and facilitate identification of novel antiretroviral factors for use as novel diagnostics, microbicides, or therapeutics against HIV infection.

Mucosal mononuclear (MMC) CCR5+CD4+ T cells of the gastrointestinal (GI) tract are selectively infected and depleted during acute HIV-1 infection. Despite early initiation of combination antiretroviral therapy (cART), gut-associated lymphoid tissue (GALT) CD4+ T cell depletion and activation persist in the majority of HIV-1 positive individuals studied. This may result from ongoing HIV-1 replication and T-cell activation despite effective cART. We hypothesized that ongoing viral replication in the GI tract during cART would result in measurable viral evolution, with divergent populations emerging over time. Subjects treated during early HIV-1 infection underwent phlebotomy and flexible sigmoidoscopy with biopsies prior to and 15-24 months post initiation of cART. At the 2(nd) biopsy, three GALT phenotypes were noted, characterized by high, intermediate and low levels of immune activation. A representative case from each phenotype was analyzed. Each subject had plasma HIV-1 RNA levels <50 copies/ml at 2(nd) GI biopsy and CD4+ T cell reconstitution in the peripheral blood. Single genome amplification of full-length HIV-1 envelope was performed for each subject pre- and post-initiation of cART in GALT and PBMC. A total of 280 confirmed single genome sequences (SGS) were analyzed for experimental cases. For each subject, maximum likelihood phylogenetic trees derived from molecular sequence data showed no evidence of evolved forms in the GALT over the study period. During treatment, HIV-1 envelope diversity in GALT-derived SGS did not increase and post-treatment GALT-derived SGS showed no substantial genetic divergence from pre-treatment sequences within transmitted groups. Similar results were obtained from PBMC-derived SGS. Our results reveal that initiation of cART during acute/early HIV-1 infection can result in the interruption of measurable viral evolution in the GALT, suggesting the absence of de-novo rounds of HIV-1 replication in this compartment during suppressive cART.

ABSTRACT: BACKGROUND: The incidence of colorectal cancer can be decreased by appropriate use of screening modalities. Patients with a family history of colon cancer and of African-American ethnicity are known to be at higher risk of developing colorectal cancer. We aimed to determine if there is a lack of physician knowledge for colorectal cancer screening guidelines based on family history and ethnicity. Between February and April 2009 an anonymous web-based survey was administered to a random sample selected from a national list of 25,000 internists, family physicians and gastroenterologists. A stratified sampling strategy was used to include practitioners from states with high as well as low CRC incidence. All data analyses were performed following data collection in 2009. RESULTS: The average knowledge score was 37 +/- 18% among the 512 respondents. Gastroenterologists averaged higher scores compared to internists, and family physicians, p = 0.001. Only 28% of physicians correctly identified the screening initiation point for African-Americans while only 12% of physicians correctly identified the screening initiation point and interval for a patient with a family history of CRC. The most commonly cited barriers to referring high-risk patients for CRC screening were 'patient refusal' and 'lack of insurance reimbursement.' CONCLUSIONS: There is a lack of knowledge amongst physicians of the screening guidelines for high-risk populations, based on family history and ethnicity. Educational programs to improve physician knowledge and to reduce perceived barriers to CRC screening are warranted to address health disparities in colorectal cancer