Microbiological spectrum and antibiotic sensitivity in endophthalmitis: a 25-year review.

PURPOSE: To identify the spectrum and susceptibility pattern of pathogens responsible for culture-positive endophthalmitis referred to a single institution and investigate possible trends in both pathogens and antibiotic sensitivities over the past 25 years. DESIGN: A retrospective, laboratory-based study of consecutive microbiological isolates. PARTICIPANTS: A total of 988 consecutive culture-positive endophthalmitis isolates from 911 eyes. METHODS: All culture-positive endophthalmitis isolates collected from 1987 to 2011 were identified. Susceptibility rates to a variety of antibiotics were calculated. Chi-square test for trend was used to detect changes in spectrum or susceptibility over time. MAIN OUTCOME MEASURES: Microbial spectrum and susceptibility pattern over time. RESULTS: A total of 988 isolates were identified from 911 eyes. The average patient age was 67 ± 18 years, and 55% of the patients were female. The most prevalent pathogens were coagulase-negative staphylococcus (39.4%), followed by Streptococcus viridans species (12.1%) and Staphylococcus aureus (11.1%). Gram-negative organisms and fungi accounted for 10.3% and 4.6% of all isolates, respectively. With the exception of 2 isolates, Enterococcus faecium and Nocardia exalbida, all the other 725 (99.7%) gram-positive bacteria tested were susceptible to vancomycin. Of the 94 gram-negative organisms tested against ceftazidime, 2 were of intermediate sensitivity and 6 were resistant. For 8 antibiotics, increasing microbial resistance over time was observed: cefazolin (P = 0.02), cefotetan (P = 0.006), cephalothin (P<0.0001), clindamycin (P = 0.04), erythromycin (P<0.0001), methicillin/oxacillin (P<0.0001), ampicillin (P = 0.01), and ceftriaxone (P = 0.006). For 3 antibiotics, increasing microbial susceptibility was observed: gentamicin (P<0.0001), tobramycin (P = 0.005), and imipenem (P<0.0001). CONCLUSIONS: Coagulase-negative staphylococcus remains the most frequently identified cause of endophthalmitis. Vancomycin and ceftazidime seem to be excellent empiric antibiotics for treating endophthalmitis. Although a statistically significant trend toward increasing microbial resistance against a variety of antibiotics, including cephalosporins and methicillin, was observed, a significant trend toward decreasing microbial resistance against aminoglycosides and imipenem also was detected.

Nonfamilial vitreous amyloidosis diagnosed by portable sutureless vitrectomy.

PURPOSE: To describe a case of primary nonfamilial vitreous amyloidosis and a novel technique for expediting vitreous biopsy. DESIGN: Interventional case report. CASE: A 43-year-old man presented with progressive deterioration of vision and was found to have bilateral vitreous opacities. A systemic medical workup including family history was noncontributory. Given a high clinical suspicion of vitreous amyloidosis, the decision was made to obtain a vitreous biopsy for ultrastructural study. An office-based pars plana sutureless vitrectomy was performed. Pathologic study of the vitreous specimen confirmed the diagnosis of amyloidosis. CONCLUSION: Vitreous amyloid deposition may occur with neither systemic involvement nor family history. Sutureless pars plana vitrectomy may facilitate diagnosis while saving time and expense for both the physician and the patient.

Efficacy of nonsimultaneous bilateral LASIK after nonsimultaneous bilateral penetrating keratoplasty.

PURPOSE: To show if nonsimultaneous bilateral laser in situ keratomileusis (LASIK) is a safe and effective procedure for patients with bilateral penetrating keratoplasty (PKP). METHODS: Five patients (10 eyes), with keratoconus, underwent PKP separately in each eye. After an average PKP follow-up of 45.8 months per eye, (range, 19-92 months), each eye underwent 1-stage LASIK using the Visx Star S3 laser to correct its residual refractive error. We used the cycloplegic refraction as the target for the LASIK surgery. Each patient had his or her eyes done separately 3 weeks apart. RESULTS: Pre-LASIK myopia averaged -3.93 +/- 2.9 D, ranging from -10.00 to +0.75 D. Pre-LASIK astigmatism averaged -3.25 +/- 0.80 D, ranging from -1.75 to -4.50 D. Mean pre-LASIK keratometry was 45.4 +/- 2.6, ranging from 42.2 to 50.5. Uncorrected visual acuity pre-LASIK averaged 20/220, ranging from 20/60 to 20/400. Best-corrected spectacle visual acuity (BCSVA) pre-LASIK averaged 20/22, ranging from 20/20 to 20/30. Nine eyes had no complications. One eye had a flap buttonhole during LASIK, and surgery was aborted. No vision was lost in this eye. Mean follow-up after LASIK in the 9 eyes was 17 +/- 15.2 months, (range, 4-56 months). Mean post-LASIK ametropia in these 9 eyes was +0.25 +/- 0.45 D, ranging from -0.50 to +0.75 D. Average post-LASIK astigmatism was -0.33 +/- 0.38 D, ranging from 0 to -0.75 D. In the 9 treated eyes, uncorrected vision post-LASIK averaged 20/25, ranging from 20/20 to 20/30. BCSVA post-LASIK averaged 20/21, ranging from 20/20 to 20/25. No lines of visual acuity were lost in any of the eyes. CONCLUSION: Young patients who have had bilateral PKP, with good postoperative vision and low levels of myopia, astigmatism, and minimal wound override, are good candidates for bilateral nonsimultaneous LASIK. Further studies can now be done on the performance of bilateral simultaneous LASIK in patients who have had corneal transplant surgery in both of their eyes.

Cyclic AMP elevates tubulin expression without increasing intrinsic axon growth capacity.

Exposing rat dorsal root ganglion (DRG) neurons to dibutyryl cAMP (db-cAMP) enables central branches to regenerate in the spinal cord by nullifying the ability of CNS myelin to inhibit elongation. A conditioning lesion (CL) promotes similar regeneration of central branches in the spinal cord by increasing neuronal cAMP levels. It is a matter of speculation whether any of the other effects of a CL are triggered by elevated cAMP. We found that like a CL, intraganglionic injection of db-cAMP increases the expression of growth-associated tubulin isotypes. However, unlike a CL, db-cAMP does not increase the velocity at which tubulin is delivered to the tips of growing axons by slow component b (SCb). db-cAMP also fails to increase intrinsic axon growth capacity enough to raise the rate of regeneration of peripheral branches in the sciatic nerve or enable central branches to elongate long distances in an environment free of all CNS inhibitors of elongation (i.e., a peripheral nerve graft transplanted into the spinal cord at the site of dorsal column transection). Thus, the increase in cAMP induced by a CL induces some, but not all, of the changes that may be necessary to increase intrinsic axon growth capacity.

Plasma ghrelin levels are normal in obese patients with idiopathic intracranial hypertension (pseudotumor cerebri).

PURPOSE: Idiopathic intracranial hypertension (IIH) occurs predominantly in young, obese women. Weight loss may alleviate symptoms of IIH yet may be difficult to achieve. Ghrelin, a gastric hormone, is involved in normal body weight and appetite regulation. Its levels are elevated in syndromes of overeating and decline in simple obesity. We postulated that fasting plasma ghrelin levels are elevated in IIH patients and that the typical postprandial decline in plasma ghrelin may not occur. DESIGN: Prospective, observational case-control study. METHODS: Prospective study. SETTING: University hospital and clinic. STUDY POPULATION: Sixty-five patients with a diagnosis of IIH and 25 obese control patients (screened for IIH symptoms). Patients with intracranial abnormalities or a history of gastric surgery were excluded. OBSERVATION PROCEDURE: Fasting plasma ghrelin, leptin, and insulin levels were assessed between 8 am and 10 am. Subjects were fed a standard breakfast, and postprandial ghrelin levels were measured 30 minutes later. RESULTS: Fasting plasma ghrelin levels negatively correlated with body mass index in both IIH subjects (r = -.48) and controls; leptin showed a positive correlation with body mass index in both IIH (r =.59) and controls. Levels were not significantly different between the groups. Postprandial ghrelin declined by 71 +/- 31 (95% CI) pg/ml in the IIH group and 71 +/- 35 (95% CI) pg/ml in the control group. CONCLUSION: Plasma ghrelin levels, both fasting and postprandial, do not differ between IIH patients and obese controls. Obese IIH patients should be encouraged to lose weight and referred for medical weight loss management to maximize their chances of alleviating their symptoms.