High delayed mortality after the first episode of Clostridium difficile infection.

Clostridium difficile infection (CDI) is characterized by a high delayed and unrelated mortality. Predicting delayed mortality in CDI patients could allow the implementation of interventions that could reduce these events. A prospective multicentric study was carried out to investigate prognostic factors associated with mortality. It was based on a cohort (July 2015 to February 2016) of 295 patients presenting with CDI. Logistic regression was used and the model was calibrated using the Hosmer-Lemeshow test. The mortality rate at 75 days in our series was 18%. Age (>65 years), comorbidity (defined by heart failure, diabetes mellitus with any organ lesion, renal failure, active neoplasia or immunosuppression) and fecal incontinence at clinical presentation were associated with delayed (75-day) mortality. When present, each of the aforementioned variables added one point to the score. Mortalities with 0, 1, 2 and 3 points were 0%, 9.4%, 18.5% and 38.2%, respectively. The area under the ROC curve was 0.743, and the Hosmer-Lemeshow goodness-of-fit test p value was 0.875. Therefore, the prediction of high delayed mortality in CDI patients by our scoring system could promote measures for increasing survival in suitable cases.

In vitro adherence of conjunctival bacteria to different oculoplastic materials.

AIM: To investigate the resistance to bacterial adhesion of materials used in oculoplastic surgery, particularly materials used in the manufacture of orbital implants. METHODS: Seven organisms of conjunctival flora (two strains of Staphylococcus epidermidis and one strain each of Staphylococcus aureus, Staphylococcus hominis, Corynebacterium amycolatum, Acinetobacter calcoaceticus, and Serratia marcescens) were selected. A lactic acid bacterium (Lactobacillus rhamnosus) was also included as positive control because of its well-known adhesion ability. Eight materials used to make oculoplastic prostheses were selected (glass, steel, polytetrafluoroethylene, polymethylmethacrylate, silicone from orbital implants, commercial silicone, porous polyethylene, and semi-smooth polyethylene). Materials surfaces and biofilms developed by strains were observed by scanning electron microscopy. Kinetics of growth and adhesion of bacterial strains were determined by spectrophotometry. Each strain was incubated in contact with plates of the different materials. After growth, attached bacteria were re-suspended and colony-forming units (CFUs) were counted. The number of CFUs per square millimetre of material was statistically analyzed. RESULTS: A mature biofilm was observed in studied strains except Staphylococcus hominis, which simply produced a microcolony. Materials showed a smooth surface on the microbial scale, although steel exhibited 1.0-µm-diameter grooves. Most organisms showed significant differences in adhesion according to the material. There were also significant differences in the total number of CFUs per square millimetre from each material (P=0.044). CFU counts were significantly higher in porous polyethylene than in silicone from orbital implants (P=0.038). CONCLUSION: Silicone orbital implants can resist microbial colonization better than porous polyethylene implants.

Orbital implant infection by Corynebacterium amycolatum.

Corynebacterium amycolatum is a saprophyte gram-positive bacillus of the skin flora. It has been linked to diverse infections in immunocompromised patients and also of different types of prostheses. However, to our knowledge, there are no reports on its ability to produce ocular infections or to grow over alloplastic materials for orbital surgery. We present a case of orbital implant exposure including pure isolation of C. amycolatum. The patient was referred for discharge in his socket. After removal of the artificial eye, a large area of implant exposure and signs of chronic infection were observed. A microbiological sample was taken by rubbing the implant with a sterile swab. The sample was cultured and C. amycolatum was identified by phenotypical characterization. Other microbial species were not isolated. Besides being able to adhere to cardiac and joint devices, this case shows that C. amycolatum is a potential infectious agent of orbital prostheses. Pure isolation of C. amycolatum in an ocular sample is extremely rare and suggests an etiological role of this microorganism in an ocular or periocular infection.

Study of conjunctival flora in anophthalmic patients: influence on the comfort of the socket.

PURPOSE: To investigate the relationship between conjunctival flora and comfort of the socket in anophthalmic patients. METHODS: A cross-sectional clinical study including 60 patients with unilateral anophthalmia who wear a prosthetic eye. From each patient three microbiological samples were taken from the lower conjunctival sac (healthy eye, pre-prosthesis, and retro-prosthesis space of socket). The 180 samples obtained were cultured. Samples from a randomized subgroup of 29 patients were measured by spectrophotometry at 540 nm after 48 h of growth, to determine their microbial density (MD). The grade of comfort of the socket (GCS) of each patient was established by a questionnaire. Epidemiological and clinical data of the anophthalmic socket and artificial eye care of each patient were also collected. RESULTS: MD decreased in healthy eyes (0.213 ± 0.201, P = 0.004) compared with the pre-prosthesis (0.402 ± 0.323) and retro-prosthesis (0.438 ± 0.268) samples. Pre-prosthesis MD correlated with retro-prosthesis MD (R = 0.401, P = 0.031) and healthy eye MD (R = 0.482, P = 0.008), and it was also related to poor GCS (P = 0.017). Aerobic Gram-negative bacteria in retro-prosthesis samples of patients with poor GCS was higher than in patients with good or fair GCS (P = 0.008). In the same samples, coagulase-negative staphylococci proportion (excluding S. epidermidis) increased in patients with good GCS (P = 0.030). CONCLUSIONS: Socket microflora is related to GCS. Increased pathogenic flora, especially Gram-negative bacteria, and high MD are related to discomfort, while coagulase-negative staphylococci (other than S. epidermidis) are associated with comfort.