Conjunctival flora in patients with type 1 or type 2 diabetes mellitus

Abstract

Patients with diabetes mellitus (DM) are prone to infection because glucose in the skin, urine, mucous membranes, and tears promotes growth of microorganisms. Conjunctival flora develops soon after birth, and some saprophytic conjunctival flora play a pathogenic role when immune function is compromised, which can lead to serious infection. DM is one condition that may compromise immune status. In lacrimal function tests of DM patients, a decrease in breakup time (BUT) of lacrimal film and a decrease in Schirmer's test results were seen. In the present study, conjunctival flora in patients with DM was compared with that in controls with regard to type and duration of diabetes and results of lacrimal function tests. Seventeen patients with type 1 DM (n=34 eyes), 66 patients with type 2 DM (n=132 eyes), and 50 control subjects (n=100 eyes) were included. The control group consisted of age-matched patients with no ophthalmologic problems other than refractive error. Glycosylated hemoglobin values were measured with highpressure liquid chromatography with the Hi-AUTOA1c analyzer (Kyoto Daiichi Kagatu Co., Ltd., Kyoto, Japan). Type and duration of diabetes and demographic data were recorded, and routine ophthalmologic examinations were performed; the BUT of lacrimal film was determined, and the results of Schirmer's test were assessed. Microbiologic sampling was performed twice for both eyes with sterile cotton swabs. One sample was incubated in 2 mL of brain-heart infusion broth agar; the other was incubated for the presence of fungi in Sabouraud dextrose agar. Colony morphology, hemolysis, and Gram's stain, as well as catalase, oxidase, and coagulase tests were performed. No growth was observed in 12 of 17 patients (35.4%) with type 1 DM, 28 of 66 patients (21.2%) with type 2 DM, and 25 of 50 control subjects (50%). Staphylococcus epidermidis (11.79%) and Staphylococcus aureus (11.7%) were the most frequently isolated organisms in the type 1 DM group, and S epidermidis (24.2%) and S aureus (21.2%) were the predominant organisms in the type 2 DM group. In control subjects, S epidermidis (22%), S aureus (12%), and Corynebacterium spp (10%) were the most frequently isolated organisms, and the number of eyes with growth of S aureus was significantly higher in the type 2 DM group than in the other groups (P<.01). Patients with diabetes are more prone to postoperative endophthalmitis than are nondiabetics, and preoperative application of antiseptic or antimicrobial agents to the conjunctiva may not sterilize the area. Impaired integrity of the posterior capsule may also increase the risk of endophthalmitis. Postoperative endophthalmitis is usually associated with gram-positive organisms (75%-80%); gram-negative organisms (15%-29%) and fungi (3%-13%) account for a smaller number of cases. A high rate of resistance to penicillin, ampicillin, and tetracycline was observed in S aureus isolates, although resistance to vancomycin was absent, rendering this molecule the most effective therapeutic option. In this study, S epidermi...

The conjunctival bacterial pattern of diabetics undergoing cataract surgery

“…In one of the two small-sized studies published on the diabetics conjunctival bacteria, 28,29 an increased prevalence of S. aureus was only found in diabetics type II, although the number of patients studied by Bilen et al 28 was small (17 diabetics type I, 66 diabetics type II, and 50 control subjects). But only an increased prevalence of SCN was found in the other one, 29 which only studies the flora of diabetics with retinopathy.…”

Pathogenic conjunctival bacteria associated with systemic co-morbidities of patients undergoing cataract surgery

“…42 To our knowledge, the present study contains the biggest cohort of consecutive patients undergoing their first cataract surgery in which a wide range of individual co-morbidities were associated with the prevalence of their conjunctival bacteria. Previously, Fahmi et al 27 found a correlation between male sex and the prevalence of Corynebacteria and Gram-negative rods; other small studies associated the conjunctival bacteria with a particular co-morbidity such as patients taking immunosuppressive drugs 31 or those having diabetes; 32,33 Miñ o de Kaspar et al 29 found that advanced age and patients grouped for having diabetes, immunosuppression, autoimmune conditions, and asthma had a higher rate of positive conjunctival cultures than the control group, but they did not find any gender association. Recently, 30 with fewer patients, no association was found between conjunctival bacterial prevalence and diabetes, steroid therapy, dialysis and allergic conjunctivitis, but an association was found with age above 60.…”

“…[27][28][29][30] However, very little is known about whether the clinical characteristics of this small number of patients with pathogenic bacteria colonising their conjunctivas are different. 16,[31][32][33] Today, the available data of the Human Microbiome Project reveals the possibility of determining differences between the microbiomes of healthy and unhealthy people. 34 This fact opens a new horizon in the management of infectious diseases.…”

Aerobic bacterial microbiota of the conjunctiva in diabetic patients with normal and altered glycated hemoglobin levels in two regions in Brazil

“…S. epidermidis, S. aureus, and Corynebacterium sp have also been found in diabetic patients (4) . Variations in conjunctival microbiota may occur due to both intrinsic and extrinsic changes in the body, such as geographical diversity and different socioeconomic characteristics (4,10,(12)(13)(14) . Therefore, the conjunctival aerobic microbiota of diabetic patients was studied in two different Brazilian cities: Rio Branco, in the state of Acre, in north Brazil; and Sorocaba, in the state of São Paulo, in southeastern Brazil.…”