Type-H, and Type-L COVID-19: are they different subtypes or the same?

OBJECTIVE: SARS-CoV-2 infection, which causes severe pneumonia, caused an epidemic that started in Wuhan, China in December 2019 and spread to the whole world. COVID-19 mainly affects the respiratory system and causes the development of severe pneumonia and related acute respiratory distress syndrome (ARDS) in some patients. We aimed to investigate whether COVID-19 pneumonia cases can be evaluated in different categories in clinical and radiological terms. PATIENTS AND METHODS: COVID-19 associated ARDS cases being treated with the diagnosis of severe pneumonia between March 21, 2020 and June 15, 2020 in Anesthesia Intensive Care Unit were examined and divided into 2 groups (type-L and type-H, total 29 cases) according to their clinical findings (according to whether they benefited from high PEEP and their lung compliance) and lung computed tomography findings (according to the severity of the ground glass appearance). The groups were compared with each other in terms of inflammatory markers [CRP (C reactive protein), ferritin, D Dimer, PCT (procalcitonin), white blood cell, lymphocyte count, arterial blood gas analysis] and imaging findings. RESULTS: It was observed that the prone position was beneficial in improving oxygenation in both H-type and L-type patients. 7 of 22 L-type patients were intubated and 5 of these patients died. There was no statistical difference between the two groups in terms of intubation times, hospital stays, cytokine levels, prone position application responses and mortality rates. CONCLUSIONS: Are there two separate forms of COVID-19 pneumonia, such as h-type and l-type, or are they intertwined and describe the early and late stages of the disease? This question needs to be discussed. In addition, we believe that subtyping COVID-19 pneumonia patients does not make a difference in the treatments to be applied.

Are we aware of COVID-19-related acute kidney injury in intensive care units?

OBJECTIVE: Coronavirus disease-19 (COVID-19) primarily affects the respiratory system. In some cases, the heart, kidney, liver, circulatory system, and nervous system are also affected. COVID-19-related acute kidney injury (AKI) occurs in more than 20% of hospitalized patients and more than 50% of patients in the intensive care unit (ICU). In this study, we aimed to review the prevalence of COVID-19-related acute kidney injury, risk factors, hospital and ICU length of stay, the need for renal replacement therapy. We also examined the effect of AKI on mortality in patients in the ICU that we treated during a 1-year period. PATIENTS AND METHODS: The files of patients with COVID-19 (n=220) who were treated in our ICU between March 21st, 2020, and June 1st, 2021, were analyzed retrospectively. Demographic data of the patients, laboratory data, and treatments were examined. Patients were divided into two groups, group I patients without AKI and, group II patients with AKI. The patients with AKI were evaluated according to the theKidney Disease Improving Global Outcomes (KDIGO) classification and were graded. RESULTS: Of the 220 patients included in the study, 89 were female and 131 were male. The mean age of patients with AKI (70.92±11.28 years) was statistically significantly higher than among those without AKI (58.87±13.63 years) (p<0.001). In patients with AKI, ICU length of stay, Acute Physiology and Chronic Health Evaluation (APACHE) II scores, initial lactate levels, need for mechanical ventilation, duration of mechanical ventilation, and secondary infection rates were found to be statistically significantly higher. Discharge rates from the ICU in patients without AKI were statistically higher (75.3% vs. 26.6%), and mortality rates were significantly higher in patients with AKI (67.8% vs. 14.3%). CONCLUSIONS: Various studies conducted have shown that patients with COVID-19 are at risk for AKI, and this is closely related to age, sex, and disease severity. The presence of AKI in patients with COVID-19 increases mortality, and this is more evident in patients hospitalized in the ICU. In our study, the prevalence of AKI was higher in older patients with high APACHE II scores and initial lactate levels. Comorbidities such as hypertension, chronic kidney disease, and coronary artery disease in patients with AKI were higher than in those without AKI.

Can we estimate cytokine storm from initial computed tomography images of Coronavirus disease-2019 patients?

OBJECTIVES: The present study aims to investigate whether elementary lesions detected at the time of the diagnosis, their distribution characteristics, and CT scoring can be predictive of a cytokine storm. BACKGROUND: CT might have a prognostic predictive value beyond its diagnostic value. METHODS: Sixty-eight patients, 32 with cytokine storm and 36 without cytokine storm, were included in the study. Four different scoring methods were created according to elementary lesions, distribution and involvement rate. CT scores and demographic findings of the cases were compared in the cytokine storm and non-cytokine storm groups. RESULTS: The mean age of patients was 57.72 (SD: 13.5) and 40 (58.8 %) of them were male. The cytokine storm was significantly more common among male patients and patients of older age (p=0.04).  The AUC values of CT score 1, CT score 2, CT score 3, and CT score 4 were as follows; 0.772 (95% CI; 0.651-0.892), 0.766 (95% CI; 0.647-0.885), 0.758 (95% CI; 0.639-8.78), and 0.760 (95% CI; 0.640-0.881), respectively. All CT scores had better predictive values in males. CONCLUSIONS: CT scoring at the time of admission can be used to predict cases that may develop cytokine storm later (Tab. 4, Fig. 2, Ref. 15).

The effect of beta glucan on MTX induced testicular damage in rats.

We investigated the histopathological effects of methotrexate (MTX), a chemotherapeutic agent, and beta glucan (BG), an antioxidant, on rat testis. We used four groups of Sprague-Dawley male rats: MTX, MTX + BG, BG, and control. The MTX group was exposed to a single dose of MTX on the first day of experiment. The MTX + BG group was exposed to a single dose of MTX and BG on the first day of experiment followed by BG for 4 additional days. The BG group was exposed to BG for 5 days. The control group was given saline for 5 days. On day five, all animals were sacrificed and testicular tissue was evaluated for histopathology and the terminal deoxynucleotidyl transferase (TdT) deoxyuridine triphosphate nick-end labeling assay (TUNEL) was used to detect apoptosis. The apoptotic index (AI) and testicular damage increased in the MTX group compared to the other three groups. Histopathology was reduced in the MTX + BG group compared to the MTX group. Seminiferous tubule diameter was reduced in the MTX group compared to the BG group; we found no difference between control and BG groups. The thickness of th e germinal epithelium was reduced in the MTX group compared to the other groups. We found no difference in testicular weight among the groups. We compared body weight before and after the experiment; weights in the MTX and MTX + BG groups were significantly reduced compared to controls. In the control groups, we found a statistically significant increase in body weight, whereas there was no change in the BG group. We found that MTX causes deleterious effects on testicular tissue and that beta glucan may be protective.

Predictors of stereoacuity outcome in visually mature subjects with exotropia.

The purpose of this study was to determine the predictors of stereoacuity outcome in visually mature subjects with exotropia following surgical correction. Visually mature subjects who were surgically aligned and had been tested for stereoacuity in the postoperative period were studied retrospectively. Subjects were grouped with respect to their responses to Titmus or TNO stereotests. Characteristics such as amblyopia, anisometropia, and characteristics of the exodeviation such as time of onset, duration, intermittency, presence of an A or V pattern, distance-near disparity, coexisting vertical deviation, and inferior oblique overaction, were compared between the groups. One hundred and four visually mature subjects with exotropia met the inclusion criteria. Stereoacuity was achieved in 77% of the study group and only 9% of these could achieve fine stereoacuity. Negative stereoacuity was more frequently associated with larger deviation angles, higher anisometropia, inferior oblique overaction, pattern strabismus, coexisting vertical strabismus, and distance-near disparity, but not at a statistically significant level. The optimal cutoff for strabismus duration was 20 years for a positive stereoacuity outcome. Any-level visual acuity difference was found to decrease the chance for positive stereoacuity significantly. The odds ratios for the stereoacuity positivity were 4.05 for strabismus duration <20 years, 7.9 for strabismus onset >1 year of age, 3.79 for weaker eye visual acuity >20/25 and 9.85 for intermittency of strabismus. Intermittence of exotropia was the strongest predictor for positive stereoacuity. Exotropia onset after 1 year of age, absence of any-level visual acuity difference, and strabismus duration <20 years were the other predictors with decreasing power.

Vitamin D supplementation during the first two years of life in Izmir, Turkey.

AIM: The aim of the present study was to determine the prevalence of vitamin D supplementation and risk factors for non-supplemented infants in Izmir, Turkey. METHODS: This cross-sectional study was carried out in Well-Child Care Clinics in Izmir, Turkey. Parents filled a questionnaire about socio-demographic characteristics and the use of vitamin D. SPSS version 16.0 was used for statistical analysis. RESULTS: A total of 1002 children (aged 1 to 24 months) were enrolled in the study. The supplementation rates of vitamin D were 77% in the first 3 months of life, 57% at 10 to 12 months. Economic status of family, education of parents, occupational status of mothers and parity were associated factors with the use of vitamin D supplements in infants (P<0.05). However, when the data were analyzed using logistic regression analysis, only education of mother seems to be statistically significant independent variable in decreasing non-supplementation/ irregular supplementation. CONCLUSION: Vitamin D supplementation rates seem to be not satisfactory in Izmir. Therefore, the importance of vitamin D supplementation in infants should be emphasized in every well-child care visit to prevent vitamin D deficiency.

Acute-phase reactants and cytokines in ischemic stroke: do they have any relationship with short-term mortality?

BACKGROUND: Many unknown risk factors play a role in the etiopathogenesis of stroke. The appearance of inflammatory cells within the damaged tissue after cerebral ischemia suggests that an inflammatory response may play a role in stroke pathogenesis. In our study, we examined whether an association exists between the acute-phase reactants and the levels of cytokines, the volume and diameter of the stroke, and short-term mortality in patients who were diagnosed as acute ischemic a stroke after admission to the Emergency Department. PATIENTS AND METHODS: A total of 50 consecutive patients who applied to the Emergency Service with acute ischemic stroke were enrolled in the study. Their stroke volume were calculated and serum samples were obtained as soon as they arrived into the Emergency Service. The patients were evaluated according to the Glasgow Coma Scale (GCS) and National Institutes of Health Stroke Scale (NIHSS). RESULTS: There was no significant correlations between stroke volume and levels of cytokine and acute-phase reactants in dead patient group or in living patient group. A correlation and statistical significance was found between stroke volume and hospital stay time in living patient group. In addition, GCS and NIHSS scores were correlated with stroke volume and was found a significant statistically. CONCLUSIONS: Scales such as GKS and NIHHS, which evaluate the functional state of patients, are the best indicators for defining prognosis in our daily practices. In addition, we found a positive correlation between levels of CRP (C reactive protein) and prognosis. However, we did not observe a statistically significant correlation between prognosis and other acute-phase reactants such as TNF-alpha, IL-6, IL-8, IL-10, fibrinogen, and leukocytes.

Genotoxicity assessment of vaccine adjuvant squalene.

The genotoxic potential of the vaccine adjuvant Squalene was assessed by the chromosomal aberrations (CAs), sister chromatid exchanges (SCEs) and micronucleus (MNs) tests in human lymphocytes and comet assay in both human and rat lymphocytes. Five different concentrations of squalene (1250-20,000 µg/ml for human lymphocytes and 0.07-1.12 mg/kg for rat lymphocytes) were studied. Squalene did not affect the CAs and MN frequency, in all treatments in vitro. A significant increase in SCEs was observed in almost all concentrations at 24 h treatment. Squalene did not affect significantly the comet tail length (CTL) (except 2500 µg/ml) and comet tail intensity (CTI) at all treatments in vitro. In rats, squalene significantly increased and decreased CTL and CTI in some doses. Although there are increasing and reduction in the effect, squalene cannot be regarded as genotoxic in human lymphocytes. However, further in vivo studies are required to be sure on the effect.

Effects of Enterococcus faecium supplementation and floor type on performance, morphology of erythrocytes and intestinal microbiota in broiler chickens.

1. The experiment was to study the effects of floor type and probiotic supplementation (Enterococcus faecium) on performance, morphology of erythrocytes and intestinal microbiota of male Ross 308 broiler chickens. 2. The experimental design was a factorial 2 × 2 with 6 replicates. The factors were floor type (wire floor versus wood shaving litter) and the presence or absence of probiotic. 3. Birds housed on wood shavings exhibited significantly improved weight gain and food intake. 4. Addition of E. faecium led to significantly decreased food intake and gizzard weight. Supplementation with E. faecium positively influenced the ileal and caecal microbiota, with a significant decrease in the population of Escherichia coli. 5. Erythrocyte length decreased and erythrocyte width increased in the birds housed on wood shavings.

Pharmacokinetics of florfenicol in the plasma of Japanese quail.

AIM: To determine the pharmacokinetics and bioavailability of florfenicol in the plasma of healthy Japanese quail (Coturnix japonica). METHODS: Sixty-five quail were given an I/V and I/M dose of florfenicol at 30 mg/kg bodyweight (BW). A two-period sequential design was used, with a wash-out period of 2 weeks between the different routes of administration. Concentrations of florfenicol in plasma were determined using high-performance liquid chromatography (HPLC). RESULTS: A naïve pooled data analysis approach for the plasma concentration-time profile of florfenicol was found to fit a non-compartmental open model. After I/V administration, the mean residence time (MRT), mean volume of distribution at steady state (Vss), and total body clearance of florfenicol were 12.0 (SD 0.37) h, 8.7 (SD 0.22) L/kg, and 1.3 (SD 0.08) L/h/ kg, respectively. After I/M injection, the MRT, mean absorption time (MAT), and bioavailability were 12.3 (SD 0.37) h, 0.2 (SD 0.02) h, and 79.1 (SD 1.79)%, respectively. CONCLUSIONS: The time for the concentration of florfenicol to fall below the probable effective concentration of 1 microg/ ml of approximately 10 h is sufficient for the minimum inhibitory concentration needed for many bacterial isolates. Further pharmacodynamic studies in quail are needed to evaluate a suitable dosage regimen.

Pharmacokinetics of florfenicol after intravenous and intramuscular administration in New Zealand White rabbits.

The pharmacokinetic disposition and bioavailability of florfenicol (FF) were determined after single intravenous (i.v.) and intramuscular (i.m.) administrations of 25mg/kg b.w. to ten healthy New Zealand White rabbits. Plasma FF concentrations were determined by high-performance liquid chromatography (HPLC). The plasma pharmacokinetic values for FF were best described by a one-compartment open model. The elimination half-life (t(1/2beta)) was different (p<0.05) however, the area under curve (AUC) was similar (p>0.05) after i.v. and i.m. administrations. FF was rapidly eliminated (t(1/2beta) 1.49+/-0.23 h), slowly absorbed and high (F, 88.75+/-0.22%) after i.m. injection. In addition, FF was widely distributed to the body tissues (V(ss) 0.98+/-0.05 L/kg) after i.v. injection. In this study the time that plasma concentration exceeded the concentration of 2 microg/mL was approximately 6h. For bacteria with MIC of 2 microg/mL, frequent administration at this dose would be needed to maintain the concentration above the MIC. However, it is possible that rabbit pathogens may have MIC values less than 2 microg/mL which would allow for less frequent administration. Further studies are necessary to identify the range of MIC values for rabbit pathogens and to identify the most appropriate PK-PD parameter needed to predict an effective dose.

The influence of homocysteine levels on endothelial function and their relation with microvascular complications in T2DM patients without macrovascular disease.

The aim of this study was to investigate the influence of homocysteine (hcy) levels on endothelial function by the method of brachial artery ultrasonography and their relation with microvascular complications in type 2 diabetes mellitus (T2DM) patients without macrovascular disease. Fifty-nine T2DM patients with a mean age of 53.4+/-8.6 years and diabetes duration of 8.1+/-6.2 years and 16 healthy controls with a mean age of 47+/-14.5 years were included in the study. Endothelialdependent and endothelium-independent flow-mediated dilatation (FMD) were evaluated via brachial artery ultrasonography. Fasting plasma glucose (FPG), glycosylated haemoglobin (A1c), lipid profile, hcy, B12 and folic acid levels were measured. Diabetic patients and control group individuals were compared with regard to the laboratory values and brachial artery vascular reactivity. Factors influencing endothelium-dependent FMD were investigated with linear regression analysis. Age, gender, body mass index, lipid profiles and hcy levels were similar in both groups (p>0.05). Endothelium-dependent FMD percentages were significantly lower in diabetics than in the control group (7.7+/-5.9 vs. 11.7+/-7.1%, p<0.05). Endothelial-independent FMD percentage was similar for both groups (p>0.05). The upper limit of the reference hcy value was found to be 12.6 micromol/l in the control group. In the diabetic group, hcy levels were high in 33 patients and normal in 26 patients. No difference was detected between the patients with high hcy levels and those with a normal level with regard to endothelium-dependent and endothelium-independent FMD values (p>0.05). Mean hcy levels were 16+/-1.7 and 13.3+/-4.3 micromol/l in T2DM patients with microvascular complication and those with no microvascular complication, respectively (p<0.05). Regression analysis revealed that the main factors influencing the endothelial-dependent FMD were FPG, total cholesterol (TC), triglycerides (TG) and high-density lipoprotein (HDL-C) levels (p<0.05, p=0.05, p=0.05, p=0.02, respectively). Hcy, folic acid and B12 values did not influence endothelium-dependent FMD (p>0.05). Diabetes duration and A1c levels were close to being significant although they did not reach statistical significance (p=0.07 and p=0.08 respectively). Hcy levels have no effect on endothelium-dependent and endothelium-independent FMD in T2DM patients without macrovascular complications. The influence of classical atherogenic factors (such as FPG, TC, TG and HDL-C levels) on endothelium functions, detected with endothelium-dependent FMD, is greater.

Resolution in partially accomodative esotropia during occlusion treatment for amblyopia.

PURPOSE: To evaluate alignment changes in partially accommodative esotropia during occlusion treatment for amblyopia. METHOD: Changes at the deviation angles of 63 partially accommodative esotropia patients, who had occlusion treatment for amblyopia, were evaluated retrospectively. RESULTS: Mean deviation angle at the start of therapy without glasses was 45 PD (10-90 PD) and became 27 PD (5-70 PD) after at least 2 months with glasses. During 12 (2-36) months of occlusion period, mean manifest deviation angle with glasses decreased to 11 PD (0-50) (P < 0.001) and amblyopia resolved in 71.5% of the cases. After termination of amblyopia treatment 24 (38%) cases had surgery for the residual deviation but if we had planned surgery before amblyopia treatment, 81% of the patients would have had surgery. DISCUSSION: Should amblyopia be treated initially or should we operate first in patients with strabismus and amblyopia together? Our research suggests that we should not hurry to operate in high hypermetropic partially accommodative cases, which have amblyopia and a long-term history of strabismus. Initial amblyopia treatment in these cases allows time for resolution of the nonaccomodative component in strabismus and can significantly decrease the necessity for surgery.

The aetiology in paediatric aphakic glaucoma.

PURPOSE: To investigate the causes of glaucoma in children following removal of cataracts. METHODS: In total, 24 patients (37 eyes) with uncomplicated congenital cataracts who developed glaucoma following cataract removal were studied retrospectively. Cataract morphology, surgical technique, postoperative complications, time to glaucoma onset, gonioscopic findings, the presence of microcornea, and the histopathologic characteristics of the filtration angle in one case were the studied parameters. RESULTS: We found a bimodal onset of glaucoma. Early-onset glaucoma occurred at a mean age of 6 months in 15 eyes and delayed-onset glaucoma at a mean age of 12 years in 22 eyes. Early-onset glaucoma was significantly (P=0.018) more likely to be due to angle closure. With delayed-onset glaucoma, the filtration angle is open in 86% of eyes and significantly (P=0.006) more eyes in the delayed-onset group had microcornea. CONCLUSIONS: Performing cataract surgery very early in life in microphthalmic eyes and leaving residual lens material increases the risk for glaucoma. We recommend a prophylactic iridectomy in eyes at risk for pupillary block. Eyes with delayed-onset glaucoma have open filtration angles but with findings consistent with incomplete development of filtration structures. Early age at cataract extraction and microcornea are risk factors for delayed-onset glaucoma.

The sensitivity and specificity of 0.5% apraclonidine in the diagnosis of oculosympathetic paresis.

AIMS: To evaluate the sensitivity and specificity of 0.5% apraclonidine test in the diagnosis of oculosympathetic paresis (OSP). METHOD: Apraclonidine (0.5%) was administered to 31 eyes, nine with a diagnosis of Horner syndrome (HS), 22 with bilateral OSP caused by diabetes, and to 54 control eyes. All were confirmed with the cocaine test. The effects on pupil diameter and upper eyelid level were observed 1 hour later. RESULTS: Apraclonidine caused a mean dilation of 2.04 mm (range 1--4.5) (p<0.001) in the pupils with OSP and it caused pupillary constriction in the control eyes with a mean change of -0.14 mm (range 0.5 to --1) (p<0.05). It caused reversal of anisocoria in all HS cases. Its effects on both pupil diameters and upper lid levels differed significantly between the groups (p<0.001). The mean elevation in the upper lid was 1.75 mm (range 1--4) in the OSP group (p<0.001) and 0.61 mm (range 0--3) in the control group (p<0.001). CONCLUSION: The effect of the apraclonidine (0.5%) test on the pupil diameter was diagnostic for OSP and had at least the same sensitivity and specificity as the cocaine test for the diagnosis of OSP.

Is it possible to differentiate early-onset accommodative esotropia from early-onset essential esotropia?

PURPOSE: To determine the frequency of > or =2.50 diopter (D) hyperopia in infantile esotropia with onset up to the age of 6 months and by evaluating the treatment results of these cases retrospectively, to find the factors that may help to differentiate early-onset accommodative esotropia from early-onset essential esotropia. METHODS: The charts of 256 patients with infantile esotropia were reviewed. Thirtyseven cases, with hyperopia of > or =2.50 D, no other systemic and neurologic disease, and at least 1 year of follow-up, were included in this study. The age at the start of therapy, refractive error, deviation angle, type of therapy (antiaccommodative therapy, surgery) and the presence of amblyopia, latent nystagmus, inferior oblique overaction, dissociated vertical deviation and cross-fixation were recorded for each case. RESULTS: The prevalence of high hyperopia was found to be 14.4% (37/256) in infantile esotropia. In 18 of the cases (48.6%), antiaccommodative therapy alone was found to be adequate (Group I). In the remaining 19, although antiaccommodative therapy was found to decrease the deviation angle significantly (P<0.001), surgery was also required (Group II). Groups were compared with respect to age at the initial examination, refractive error, deviation angle, presence of amblyopia, anisometropia, and inferior oblique overaction, but no factor could be determined to predict the pure refractive ones (P>0.05). Essential infantile esotropia-associated findings did not help because they are rarely evident at the time of initial diagnosis. CONCLUSIONS: Half of the high hyperopic infantile esotropes could be corrected fully by antiaccommodative therapy alone, while the remaining ones could also benefit significantly. It is strongly recommended to try spectacles at first in the treatment of infantile esotropia with hyperopia > or =2.5 D.

Factors influencing treatment results in pseudophakic endophthalmitis.

PURPOSE: To evaluate risk factors, therapeutic approaches and factors associated with the poor visual outcome in pseudophakic endophthalmitis. METHODS: Data related to 28 cases with the diagnosis of endophthalmitis after cataract surgery and IOL implantation were gathered retrospectively. RESULTS: Preceding surgery was extracapsular cataract extraction (ECCE) in 18, phacoemulsification in 8 and scleral fixated intraocular lens implantation in two cases. Posterior capsule rupture and diabetes mellitus were considered to contribute to the development of endophthalmitis because of their high incidences (50% and 25%) in the study group. Microbiological studies from aqueous and vitreous humour were done in 85% of the cases and 58% were positive. S. Epidermidis was the most common organism, accounting for 50% of the isolates. All cases were given topical and systemic antibiotics. Inflammation was controlled by addition of subconjunctival antibiotics to this regimen in two, intravitreal antibiotic injection in 14, pars plana vitrectomy, total capsular and lens extraction and intravitreal antibiotic injection in three, lens exchange, intracapsular and intravitreal antibiotic injection in three cases. Six (21%) cases eventually needed evisceration. Visual acuity of 20/40 or better was achieved in 25%, and 20/100 or better in 64%. CONCLUSIONS: Treatment delay (p=0.039), capsular rupture complicating cataract surgery, especially with extracapsular cataract extraction (p=0.015), and initial visual acuity worse than hand motion (p=0.003) were strong predictors of poor visual outcome. The risk of endophthalmitis was not different forplanned ECCCE (0.26%) andphacoemulsification (0.27%) but the prognosis was better with the latter.

Does surgical technique influence cataract surgery contamination?

PURPOSE: To compare cataract surgery contamination rates in large-incision extracapsular cataract extraction (ECCE) and phacoemulsification (PE), we studied 65 cases prospectively. METHODS: Thirty-five cases were operated by large-incision ECCE (Group I) and 30 by PE (Group II). Conjunctival swab cultures were taken immediately before surgery and anterior chamber aspirate was taken for culture upon completion of surgery for each case. RESULTS: Anterior chamber cultures were positive in 22.8% of the cases in group I and 23% in Group II. Frequencies of contamination in each group were no different (x2: 0.22, p>0.05). When the contaminations were evaluated in relation to operating time, prolongation of the operating time raised the contamination rate in Group I (p<0.05) but not in Group II (p>0.05). Silicone and PMMA intraocular lenses (IOL) were tested to see whether they had any additional risk of contamination. The frequencies of contaminated silicone IOL implanted cases (6/26) and contaminated PMMA IOL implanted cases (8/39) were similar (x2: 0.36, p>0. 05). CONCLUSIONS: Although the architecture of the incision and irrigation dynamics provided an advantage to the PE technique as the operating time became longer, routine PE was not superior to classical ECCE with respect to contamination when performed in the same circumstances. Prolonging the operating time raised the contamination rate in classical ECCE.

Microbial keratitis following penetrating keratoplasty.

PURPOSE: To investigate the prevalence of microbial keratitis, predisposing risk factors and treatment modalities in patients who developed keratitis following penetrating keratoplasty (PK). PATIENTS AND METHODS: The records of 285 patients who had undergone PK between January 1991 and December 1995 in a tertiary care center were reviewed. Patients who developed postoperative microbial keratitis were evaluated for predisposing risk factors, microbiological etiology, response to broad spectrum antibiotic therapy and subsequent PK. Patients were mainly treated with fortified topical antibiotics with or without repeat PK. RESULTS: Of the 285 patient records reviewed, microbial keratitis developed in 21 eyes of 21 patients (7.4%). Seventy-one percent of infections occurred within 6 months after grafting. Keratitis initially began from the donor-recipient border in 16 cases (76.2%) and were central or paracentral in 5 patients. Predisposing risk factors included loose or exposed suture (9), suture removal (1), persistent epithelial defect (3), graft failure (3), contact lens wear (1), Stevens-Johnson syndrome (1). Fifteen (71.4%) patients were culture-positive consisting of Streptococcus pneumoniae (7), Staphylococcus aureus (5), Pseudomonas aureginosa (2), and Hemophilus influenzae (1). Forty-three percent of patients were successfully treated with medical therapy only. Seven patients underwent second PK for visual rehabilitation and 4 for tectonic purposes. After medical and surgical therapy, graft clarity was achieved in 17 (81%) of patients. CONCLUSIONS: The microbial keratitis following PK is a major postoperative problem affecting the long term prognosis. Careful selection of patients, and preoperative and postoperative control of risk factors, may decrease the frequency of this complication. Several factors, including loose or exposed sutures, epithelial defects, ocular surface disorders, and graft failure, may predispose patients to develop microbial keratitis following PK.