Recurrent Clostridium difficile infection is associated with treatment failure and prolonged illness in cancer patients.

BACKGROUND: Cancer patients are susceptible to recurrent Clostridium difficile infection (CDI) that is increasing globally, necessitating new approaches to prevent fatal consequences. We examined the clinical characteristics of cancer patients with recurrent CDI (RCDI). PATIENTS AND METHODS: A retrospective review of cancer patients with C. difficile-positive test between January 2015 and May 2017 was carried out. CDI was defined as diarrhea and toxigenic C. difficile detection in the stool by nucleic acid amplification test and enzyme immunoassay. Patients having two CDI episodes were categorized as single recurrent CDI (SRCDI), and those having three or more CDI episodes were categorized as multiple recurrent CDI (MRCDI). Treatment failure was defined as the requirement of antimicrobial alteration or repetition. RESULTS: We included 170 patients having 270 CDI episodes; 85 patients had non-RCDI, and 85 had RCDI; 14 of them had MRCDI. Previous hospitalization and immunosuppressant use were more frequent in MRCDI group than in SRCDI group (P=0.009 and 0.002, respectively). Physicians treated more SRCDI episodes than MRCDI episodes with metronidazole alone (P=0.017), whereas, more MRCDI episodes needed combination antimicrobials (P=0.072). The mean duration of CDI treatment was longer in the MRCDI group than in the SRCDI group (P=0.030). MRCDI was associated with treatment failure more than SRCDI (P=0.021). The risk for a recurrent episode of CDI was increased in patients who had the following features of the first CDI episode: previous use of antibiotic, NSAID, immunosuppressant, chemotherapy, comorbidities, CDI treatment failure, and severe CDI (P<0.05). CONCLUSION: Risk factors for RCDI in cancer patients are similar to those without cancer, with the exception of chemotherapy that is only given to cancer patients. Long CDI treatment and CDI treatment failure are associated with MRCDI.

Safety of endoscopy in cancer patients with thrombocytopenia and neutropenia.

BACKGROUND AND AIMS: Cancer patients are prone to thrombocytopenia and neutropenia, which increase the risk of bleeding and infection. We assessed the safety of endoscopic procedures in cancer patients with thrombocytopenia and/or neutropenia. METHODS: We studied consecutive cancer patients with thrombocytopenia and/or neutropenia who underwent endoscopic procedures from 2010 through 2015. Neutropenia was defined as an absolute neutrophil count (ANC) <1000 cells/µL, and thrombocytopenia as a platelet count <100 × 103/µL. Univariate and multivariate generalized estimating equation models were used to assess factors associated with risk of adverse events (AEs) or death. RESULTS: We identified 588 patients who underwent 783 procedures; 608 procedures were performed in the setting of thrombocytopenia and 675 procedures in the setting of neutropenia. Concurrent neutropenia and thrombocytopenia were recorded in 500 endoscopies. Twenty-four patients (4.1%) experienced infectious AEs, whereas 29 (4.9%) experienced bleeding AEs within 1 week of the procedure. On multivariate analysis, platelet count ≤50 × 103/µL was associated with risk of bleeding AEs. In contrast, poor performance status was associated with increased risk of infection AEs (P < .01). No association was observed between low ANC and infectious AEs. Poor performance status (P < .01) and platelet count ≤100 × 103/µL (P < .05) were associated with increased risk of 30-day mortality. A persistent platelet count <20 × 103/µL after the procedure, with a baseline platelet count of ≤20 × 103/µL before the procedure, was associated with significant risk of bleeding AEs compared with a platelet count >20 × 103/µL after the procedure (P < .01); furthermore, if the platelet count increased to >50 × 103/µL after the procedure, the bleeding risk after the procedure was greatly reduced (P < .01). CONCLUSIONS: Endoscopic procedures are relatively safe in cancer patients with platelet count >50 × 103/µL. Nevertheless, a platelet count of ≥20 × 103/µL could be an appropriate threshold for platelet transfusion if 50 × 103/µL is difficult to achieve. The functional status of the patient, in the absence of the need for urgent or necessary endoscopic interventions, should be considered when deciding whether to perform endoscopy. The risk of procedure and the ANC did not seem to affect the outcomes.

Immune-checkpoint inhibitor-induced diarrhea and colitis in patients with advanced malignancies: retrospective review at MD Anderson.

BACKGROUND: Immune checkpoint inhibitors (ICPIs) are gaining increasing popularity as an efficacious treatment for advanced malignancies. ICPI treatment can be complicated by diarrhea and colitis. Systemic steroids are the first line treatment. Infliximab is reserved for severe refractory cases. We aimed to assess the impact of ICPI-induced diarrhea and colitis and their immunosuppressive treatment on patients' outcomes. METHODS: This retrospective analysis was conducted in 327 cancer patients who received ICPIs between 2011 and 2017. Patients with ICPI-induced toxicities in other organs were excluded. We collected data about patient demographics, clinical variables, and overall survival. We used descriptive analysis to compare different groups based on the occurrence and the treatment of diarrhea and colitis. Kaplan-Meier and log-rank test were used to estimate and compare overall survival durations between groups. RESULTS: Diarrhea was recorded in 117 (36%) patients; 79 (24%) of them required immunosuppressive treatment of either systemic corticosteroid without infliximab (n = 44) or with infliximab (n = 35). Caucasian ethnicity, melanoma, stage 3 cancer, and ipilimumab were predictors of colitis that requires immunosuppression. Patients who required immunosuppressants had better overall survival than those who did not require treatment for colitis or diarrhea (P < 0.001). Immunosuppression for diarrhea or colitis did not affect the overall survival significantly (P = 0.232), nor did the choice of treatment (corticosteroids with vs. without infliximab; P = 0.768). Diarrhea was an independent predictor of a favorable overall survival (P < 0.001), irrespective of treatment need (P = 0.003). We confirmed the same results in a subgroup analysis for patients with stage IV malignancies only. Patients who received long duration of steroid treatment (> 30 days) had numerically higher infection rate than those who received steroid for shorter duration (40.4 vs. 25.8%, P = 0.160). Likewise, long duration of steroid without infliximab was associated with increased risk of infection compared to short duration of steroid with infliximab (42.9% vs. 14.3%, P = 0.089). CONCLUSIONS: Patients with ICPI-induced diarrhea or colitis have improved survival outcomes. Diarrhea is an independent predictor of an improved survival regardless of treatment requirement. Immunosuppressive treatment for diarrhea did not significantly affect overall survival, however, infection rates were numerically higher among patients who received steroids for a long duration. Therefore, early non-steroid immunosuppressive therapy may ensure a more favorable overall outcome.

Endoscopic and Histologic Features of Immune Checkpoint Inhibitor-Related Colitis.

Background: Diarrhea and colitis are the second most common immune checkpoint inhibitor (ICPI)-induced adverse events. However, a comprehensive characterization of the endoscopic and histologic features of ICPI-induced diarrhea and colitis is lacking. Therefore, we aimed to describe endoscopic and histologic features of ICPI-induced gastrointestinal toxicities and to assess their association with patients' clinical characteristics and outcomes. Methods: We retrospectively reviewed records of 53 patients with ICPI-related diarrhea/colitis between 2011 and 2017. We collected data on demographics, diarrhea/colitis grade, treatment, and endoscopic and histologic findings. Long-term follow-up included repeat endoscopy findings, diarrhea recurrence, and overall survival. We compared groups by treatment, endoscopic and histologic findings, and constructed Kaplan-Meier survival curves. Results: Most patients had grade 2 or higher diarrhea (87%) and colitis (60%). Thirty-one patients were successfully treated with corticosteroids, and 22 additionally required infliximab. On endoscopy, 21 (40%) patients had ulcerations and 22 (42%) had nonulcerative inflammation. Patients with ulcerations had more steroid-refractory disease (P = 0.044) and high-grade diarrhea (P = 0.033). Histology showed mostly acute (23%) or chronic (60%) inflammation. During mean follow-up duration of 18.9 months, 19 (36%) developed recurrent diarrhea. Most patients had persistent endoscopic (8/13, 62%) and histologic (9/11, 82%) inflammation. Patients with higher-grade adverse events had improved survival. Higher-grade colitis was associated with endoscopic inflammation (P = 0.039), but grade of diarrhea was not associated with endoscopic inflammation or grade of colitis. Conclusion: 10.1093/ibd/izy104_video1izy104.video15808053084001.

Mutation spectrum and risk of colorectal cancer in African American families with Lynch syndrome.

BACKGROUND & AIMS: African Americans (AAs) have the highest incidence of and mortality resulting from colorectal cancer (CRC) in the United States. Few data are available on genetic and nongenetic risk factors for CRC among AAs. Little is known about cancer risks and mutations in mismatch repair (MMR) genes in AAs with the most common inherited CRC condition, Lynch syndrome. We aimed to characterize phenotype, mutation spectrum, and risk of CRC in AAs with Lynch syndrome. METHODS: We performed a retrospective study of AAs with mutations in MMR genes (MLH1, MSH2, MSH6, and PMS2) using databases from 13 US referral centers. We analyzed data on personal and family histories of cancer. Modified segregation analysis conditioned on ascertainment criteria was used to estimate age- and sex-specific CRC cumulative risk, studying members of the mutation-carrying families. RESULTS: We identified 51 AA families with deleterious mutations that disrupt function of the MMR gene product: 31 in MLH1 (61%), 11 in MSH2 (21%), 3 in MSH6 (6%), and 6 in PMS2 (12%); 8 mutations were detected in more than 1 individual, and 11 have not been previously reported. In the 920 members of the 51 families with deleterious mutations, the cumulative risks of CRC at 80 years of age were estimated to be 36.2% (95% confidence interval [CI], 10.5%-83.9%) for men and 29.7% (95% CI, 8.31%-76.1%) for women. CRC risk was significantly higher among individuals with mutations in MLH1 or MSH2 (hazard ratio, 13.9; 95% CI, 3.44-56.5). CONCLUSIONS: We estimate the cumulative risk for CRC in AAs with MMR gene mutations to be similar to that of individuals of European descent with Lynch syndrome. Two-thirds of mutations were found in MLH1, some of which were found in multiple individuals and some that have not been previously reported. Differences in mutation spectrum are likely to reflect the genetic diversity of this population.

Natural language processing as an alternative to manual reporting of colonoscopy quality metrics.

BACKGROUND AND AIMS: The adenoma detection rate (ADR) is a quality metric tied to interval colon cancer occurrence. However, manual extraction of data to calculate and track the ADR in clinical practice is labor-intensive. To overcome this difficulty, we developed a natural language processing (NLP) method to identify adenomas and sessile serrated adenomas (SSAs) in patients undergoing their first screening colonoscopy. We compared the NLP-generated results with that of manual data extraction to test the accuracy of NLP and report on colonoscopy quality metrics using NLP. METHODS: Identification of screening colonoscopies using NLP was compared with that using the manual method for 12,748 patients who underwent colonoscopies from July 2010 to February 2013. Also, identification of adenomas and SSAs using NLP was compared with that using the manual method with 2259 matched patient records. Colonoscopy ADRs using these methods were generated for each physician. RESULTS: NLP correctly identified 91.3% of the screening examinations, whereas the manual method identified 87.8% of them. Both the manual method and NLP correctly identified examinations of patients with adenomas and SSAs in the matched records almost perfectly. Both NLP and the manual method produced comparable values for ADRs for each endoscopist and for the group as a whole. CONCLUSIONS: NLP can correctly identify screening colonoscopies, accurately identify adenomas and SSAs in a pathology database, and provide real-time quality metrics for colonoscopy.

Estrogen enhances recovery from radiation-induced spermatogonial arrest in rat testes.

Irradiation of LBNF(1) rat testes induces spermatogonial differentiation arrest, which can be reversed by gonadotropin-releasing hormone (GnRH) antagonist-induced suppression of intratesticular testosterone (ITT) and follicle-stimulating hormone (FSH). Although exogenous estrogen treatment also enhanced spermatogenic recovery, as measured by the tubule differentiation index (TDI), it was not clear whether estrogen stimulated spermatogonial differentiation only by further suppressing ITT or by an additional independent mechanism as well. To resolve this question, we performed the following experiments. At 15 weeks after irradiation, rats were treated with GnRH antagonist; some also received 17beta-estradiol (E2) and were killed 4 weeks later. GnRH antagonist treatment increased the TDI from 0% to 8%, and addition of E2 further increased the TDI to 39%. However, E2 addition further reduced ITT from 7 ng/g testis, observed with GnRH antagonist to 3 ng/g testis, so decreased ITT levels might have contributed to recovery. Next GnRH antagonist-treated rats were given exogenous testosterone and flutamide to stabilize ITT levels and block its action. This increased TDI slightly from 8% to 13%, but the further addition of E2 significantly raised the TDI to 27%, indicating it acted by a mechanism independent of ITT levels. Plots of TDI for all treatment groups compared with ITT, FSH, or a linear combination of ITT and FSH showed that treatments including E2 produced higher TDI values than did treatments without E2. These results indicate that there was an effect of E2 on spermatogonial differentiation because of an additional direct action on the testis that is unrelated to its suppression of testosterone or gonadotropins.

Restoration of spermatogenesis in dibromochloropropane (DBCP)-treated rats by hormone suppression.

The exposure of men to the nematocide dibromochloropropane (DBCP) has caused prolonged oligo- and azoospermia, which occasionally reverses spontaneously. We recently demonstrated that in testes of rats treated with a dose of DBCP sufficient to reduce the percentage of tubules producing differentiating germ cells (tubule differentiation index, TDI) to 20%, the tubules lacking differentiating cells contained type A spermatogonia. To determine whether these type A spermatogonia could be stimulated to differentiate, as had been demonstrated previously in other models of toxicant-induced sterility, we suppressed intratesticular testosterone and serum follicle stimulating hormone (FSH) levels with the GnRH agonist Lupron (leuprolide). When the GnRH agonist was given for 10 weeks starting immediately after DBCP exposure, the TDI was maintained at 94%. Even when GnRH-agonist treatment was stopped at week 10, the TDI remained between 65 and 80% 10 weeks later. Late spermatid counts averaged 10 x 10(6) per testis for the GnRH-agonist-treated rats at week 20 compared with 1.7 x 10(6) per testis in rats treated with only DBCP. To determine whether spermatogonial differentiation could be stimulated after the TDI had declined to below 30%, we initiated GnRH-agonist treatment 6 weeks after DBCP exposure. The GnRH treatment increased the TDI to 53% at week 16. These results indicate that, if the same principles apply to humans, suppression of testosterone may be applied to restore spermatogenesis in men rendered azoospermic by DBCP or other reproductive toxicants.

Dibromochloropropane inhibits spermatogonial development in rats.

Exposure to the nematocide dibromochloropropane (DBCP) has caused prolonged oligo- and azoospermia in men. There are questions regarding the cellular targets resulting in this effect. In this study we characterized an animal model, in which four daily injections of DBCP produced prolonged oligospermia in LBNF(1) rats without any indication of recovery. Between 6 and 20 weeks after DBCP treatment, 70% of seminiferous tubules showed an epithelium with Sertoli cells but no differentiating germ cells. About 20% of tubules contained differentiating germ cells and 10% showed occlusion or major morphologic alterations to Sertoli cells. Since gonadotropin levels and intratesticular testosterone (ITT) concentrations were elevated in the DBCP-treated rats, the failure of spermatogonial development could not have been a result of lack of these hormones. The tubules without differentiating germ cells contained actively proliferating and dividing type A spermatogonia, which underwent apoptosis instead of differentiation. Thus, the target for the damaging effect appears not to be the killing of stem spermatogonia, but the loss of their ability to undergo differentiation. The presence of type A spermatogonia in the atrophic tubules indicates the potential for intervention to restore spermatogenesis.