Faculty Bibliography

The intestinal microbiome is emerging as a crucial mediator between external insults and systemic infections. New research suggests that our intestinal microorganisms contribute to critical illness and the development of non-gastrointestinal infectious diseases. Common pathways include a loss of fecal intestinal bacterial diversity and a disproportionate increase in toxogenic bacterial species. Therapeutic interventions targeting the microbiome - primarily probiotics - have yielded limited results to date. However, knowledge in this area is rapidly expanding and microbiome-based therapy such as short-chain fatty acids may eventually become a standard strategy for preventing systemic infections in the context of critical illness.

BACKGROUND: The diagnosis of celiac disease is dependent on the quality of biopsy specimens obtained at EGD. Endoscopists may obtain a single- or double-biopsy specimen with each pass of the forceps. OBJECTIVE: To compare the quality of biopsy specimens obtained with the single-biopsy and double-biopsy techniques. DESIGN: Prospective cohort study. SETTING: U.S. tertiary-care university hospital. PATIENTS: Patients undergoing upper endoscopy with confirmed, suspected, or unknown celiac disease status. INTERVENTIONS: Four biopsy specimens from the second portion of the duodenum: 2 by using the single-biopsy technique (1 bite per pass of the forceps) and an additional 2 by using the double-biopsy technique (2 bites per pass of the forceps). Specimens were blindly reviewed to determine orientation, consecutive crypt-to-villous units, and Marsh score. MAIN OUTCOME MEASUREMENTS: Proportion of well-oriented biopsy specimens. RESULTS: Patients (N = 86) were enrolled, 47% with known celiac disease, 36% with suspected celiac disease, and 17% with an unknown celiac disease status. Well-oriented biopsy specimens were noted in 66% of patients with the single-biopsy technique and 42% of patients with the double-biopsy technique (P < .01). Analysis of matched pairs showed improved orientation with the single-biopsy technique (odds ratio 3.1; 95% confidence interval, 1.5-7.1; P < .01). This persisted in subgroup analysis of patients with known celiac disease (P = .02), villous atrophy (P = .02), and a final diagnosis of celiac disease (P < .01). LIMITATIONS: A single-center trial. CONCLUSION: The single-biopsy technique improves the yield of well-oriented duodenal biopsy specimens. Endoscopists should consider taking only 1 biopsy specimen per pass of the forceps in patients undergoing biopsies of the duodenal mucosa.

OBJECTIVE: To evaluate responses to mycophenolate mofetil (MMF) and intravenous cyclophosphamide (CYC) in lupus nephritis in a multiethnic population. METHODS: This was a retrospective study of all patients with systemic lupus erythematosus (SLE) that underwent kidney biopsy at New York University Medical Center. Patients with followup of at least 6 months were included. Clinical response was defined as complete (return to +/- 10% of normal) or partial (improvement of 50% in abnormal renal measurements). RESULTS: Ninty-nine patients were included in the study: 86% females, 86% non-Caucasian, age 34.2 +/- 1.1 years, 62% with proliferative nephritis (PN; ISN/RPS-III and IV), and 32% with membranous nephritis (MN; ISN/RPS-V). Of the 70 patients with PN, 37 were treated with CYC and 33 with MMF. The baseline characteristics of the 2 treatment groups were different in the incidence of ISN/RPS-IV, values of serum creatinine and serum albumin, and type of insurance (p < 0.05). The response rate was greater in the MMF than in the CYC group (70% vs 41%). Responses to MMF were different in Asians (11/11), Caucasians (4/5), African Americans (3/5), and Hispanics (5/11). Responses to CYC had a similar distribution (Asians 6/10, Caucasians 4/5, African Americans 4/9, Hispanics 1/11). In the MN group (N = 23) responses were similar to the PN group (73% MMF and 38% CYC). After adjusting for race, serum creatinine, serum albumin, type of insurance, and class of nephritis, in a logistic regression model, response to MMF was superior to CYC: OR 6.2 (95% CI 1.9-20.2). Hispanics had worse outcome than Caucasians (OR 0.17). Longterm followup suggested no difference in maintenance with MMF or CYC. CONCLUSION: After controlling for the fact that less severe nephritis is preferentially treated with MMF, we found overall that response to MMF was superior to CYC. In this US population, ethnicity was observed to have an influence on response