Fatal Neutropenic Enterocolitis Caused by Stenotrophomonas maltophilia: A Rare and Underrecognized Entity.

Although Stenotrophomonas maltophilia causes substantial morbidity and mortality in immunocompromised patients, it has not been described as a causal pathogen of neutropenic enterocolitis (NEC). We describe the first case of histologically-confirmed NEC caused by S. maltophilia accompanied by bacteremia and pneumonia after salvage chemotherapy for acute myeloid leukemia relapse following a second hematopoietic stem cell transplantation. S. maltophilia should be included as a pathogenic organism of NEC in severely immunocompromised patients to prevent a delayed diagnosis, which carries a high risk of inappropriate antimicrobial selection and fatal outcome.

[Opportunistic bacteria and microbial flora in children with leukemia and neutropenic enterocolitis]. / Bacterias oportunistas y microbiota en niños con leucemia y enterocolitis neutropénica.

OBJECTIVE: to determine the prevalence of opportunistic microorganisms and microbial flora in neutropenic enterocolitis in oncohematological pediatric patients. METHODS: a prospective and observational study was done. Patients with diagnosis of acute leukemia and neutropenia were included. Stool cultures were taken to identify microorganisms and microbial flora. A χ(2) test with Yates corrections and Fisher exact test were used in the statistical analysis. RESULTS: 21 patients were included (12 male, 57.1 %). The stool cultures showed that 68 % of microorganisms were Gram-negative. The presence of microorganisms Gram-positive was 20 %, 6 % for Candida sp.; 3 % for Cryptosporidium sp.; and in 3 % were acid fast bacilli. Staphylococcus epidermidis, Enterobacter sp., and Escherichia coli were presented in pure culture. No association was found between Gram-positive and Gram-negative microorganisms with age, white cell count or pure or mixed cultures. CONCLUSIONS: although Gram-negative microorganisms were the most frequent, Gram-positive and other microorganisms that are not detected habitually in feces culture were isolated.

Objetivo: determinar la microbiota y la prevalencia de microorganismos oportunistas en niños con leucemia y enterocolitis neutropénica. Métodos: se realizó un estudio prospectivo observacional en pacientes con leucemia aguda y neutropenia. Se tomaron cultivos de heces para identificar la presencia de bacterias y microbiota. Se aplicó estadística descriptiva para su análisis. Resultados: fueron incluidos 21 pacientes (12 hombres, 57.1 %). En 68 % de los coprocultivos se observó desarrollo de microorganismos gramnegativos. La presencia de microorganismos grampositivos fue de 20 %, 6 % de Candida sp., 3 % de Cryptosporidium sp. y en 3 % se observaron bacilos ácido alcohol resistentes. Staphylococcus epidermidis, Enterobacter sp., y Escherichia coli se observaron en cultivo puro. No se encontró asociación entre microorganismos grampositivos y gramnegativos con la edad, el recuento leucocitario ni el cultivo puro o mixto.Conclusiones: aunque los microorganismos gramnegativos fueron los más frecuentes, se aislaron de manera importante grampositivos y otros que no se buscan de rutina en el coprocultivo.

Lethal human neutropenic entercolitis caused by Clostridium chauvoei in the United States: tip of the iceberg?

The patient is a 44-year-old woman with metastatic grade 3 intra-ductal carcinoma of the breast who was started on palliative chemotherapy (docetaxel) 10 days prior to admission and presented to the emergency center complaining of diffuse abdominal pain and generalized weakness. CT abdomen showed diffuse bowel wall thickening from the cecum to the transverse colon with free fluid in the pelvis. The patient was neutropenic on admission (absolute neutrophil count of 600 cells/µl). She received antibiotics for 21 days for neutropenic enterocolitis. Blood culture isolate from admission was sent for 16s rRNA gene sequencing, which identified Clostridium chauvoei. While C. chauvoei has a long history of veterinary importance, this is the first documented case of infection caused by C. chauvoei in a human in the United States. C. chauvoei has a close phylogenetic relationship with C. septicum making the two species difficult to differentiate using conventional microbiologic methods. With increased use of more reliable detection methods the actual prevalence of C. chauvoei causing human disease may be higher than currently recognized.

Systematic review of case reports concerning adults suffering from neutropenic enterocolitis.

INTRODUCTION: Neutropenic enterocolitis (NEC) is a well recognised clinical-pathological and life-threatening complication in patients suffering from several conditions, including solid and haematological malignancies or aplastic anaemia. OBJECTIVE: This review was aimed at evaluating overall NEC mortality rate, describing clinical diagnostic findings and therapeutical interventions reported in the literature and generating a hypothesis regarding factors influencing mortality and surgical intervention. MATERIALS AND METHODS: An advanced search was made in Medline, Embase, Lilacs and Google. Additional strategies included manual search of specific journals. Reports were considered if they described case definition, inclusion and exclusion criteria. RESULTS: 275 cases were selected; 109 were from individual data and 40 from grouped data. Comparing data between case reports and case series revealed no significant differences related to mortality, surgical intervention, sex or age. Higher mortality (chi2 = 7.51 p = 0.006) was found in women (50%) compared to men (28%). No significant difference was found between antibiotic combinations and mortality (chi(2) = 12.85 df 13 p = 0.45). Mortality (chi2 = 3.89 df 1, p = 0.049), surgical intervention (chi2 = 7.64 df 1, p = 0.006) and duration of diarrhoea (chi2 = 4.71 df 1, p = 0.043) were significantly different in 26.4% of individuals using antifungal agents; death occurred in 81% of patients! who did not receive such medication compared to 19% individuals reported as being treated with antifungal agents. CONCLUSION: The current evidence suggests that antifungal agents should be used early in patients suffering from NEC. However, this hypothesis must be evaluated in multi-centric, randomised controlled trials.

[Clinical and microbiological characteristics of neutropenic enterocolitis in adults with blood cancer in the National Cancer Institute of Bogota D.C. (Colombia)]. / Características clínicas y microbiológicas de la colitis neutropénica en adultos con neoplasias hematológicas del Instituto Nacional de Cancerología de Bogotá D.C. (Colombia).

OBJECTIVES: This study describes the clinical, epidemiological and microbiological characteristics of adult patients with blood cancer and neutropenic enterocolitis treated in the Instituto Nacional de Cancerologia (National Cancer Institute) in Bogota, Colombia. METHODS: The clinical histories of 692 adult patients hospitalized in the Instituto Nacional de Cancerologia between 1997 and 2001 with a diagnosis of leukemia or lymphoma were reviewed. Thirty-five of these cases met the criteria for probable or confirmed neutropenic enterocolitis. RESULTS: Twenty-two cases were confirmed and the remaining 13 were probable neutropenic enterocolitis. All patients were undergoing chemotherapy and all presented watery diarrhea and abdominal pain. In addition, 17% had melena and 25% severe vomiting. Eight of 26 stool cultures (30%) and 17 of 32 (58%) blood cultures were positive for potentially pathogenic microorganisms, particularly gram-negative bacilli. Three patients with probable neutropenic enterocolitis and ten confirmed cases died (37%); mortality was higher among patients who were managed surgically. CONCLUSION: Neutropenic colitis presents as a multifactorial syndrome in patients with blood cancer undergoing cytotoxic therapy with agents such as cytosine arabinoside, etoposide, vincristine, cyclophosphamide and corticoids. This highly lethal complication is partly due to infections caused by gram-negative bacilli.