External Ocular Surface Bacterial Isolates and their Antimicrobial Susceptibility Patterns among Pre-operative Cataract Patients at Mulago National Hospital in Kampala, Uganda.

Endophthalmitis is a severe complication of cataract surgery which leads to high ocular morbidity and visual loss even with antibiotic treatment. Bacterial ocular floras are the implicated causative agents. This study was undertaken to evaluate the external ocular surface bacterial isolates and their antimicrobial susceptibility patterns among pre-operative cataract patients at Mulago National Hospital. This cross sectional study enrolled consecutively 131 patients scheduled for routine cataract surgery in the Department of Ophthalmology at Mulago National Hospital in Kampala, Uganda. Eyelid margin and conjunctival swabs were collected and processed using standard microbiological procedures to identify bacterial isolates and their respective antimicrobial susceptibility patterns. Of 131 patients involved (mean age 63.3 ± 14.5 years), 54.2% (71/131) were females. The eyelid margin and conjunctival samples were culture positive in 59.5% (78/138) and 45.8% (60/138) respectively. The most common organisms identified were Coagulase-negative Staphylococci (CoNS) [65.9% (91/138)] and Staphylococcus aureus [21.0% (29/138)]. CoNS showed the highest resistance to tetracycline (58.2%, 53/91) and erythromycin (38.5%, 35/91), whereas in S. aureus the resistance to tetracycline and erythromycin were 55.2% (16/29) and 31.0% (9/29) respectively. Methicillin resistant CoNS (MRS) and Methicillin resistance S. aureus (MRSA) were 31.9% (29/91) and 27.6% (8/29) respectively. There were low resistance rates for CoNS, S. aureus and other bacterial isolates to ciprofloxacin (11.1%-24.2%), gentamicin (5.6-31.0%), tobramycin (17.2% -25.3%) and vancomycin (0.0%). CoNS and S. aureus are the most common bacterial isolates found on the external ocular surface of the pre-operative cataract patients. Ciprofloxacin, gentamicin, tobramycin and vancomycin showed the lowest resistance rates to all bacterial isolates, therefore may be used to reduce bacteria load in the conjunctiva sac among cataract patients prior to surgery

Two forms of death in ageing Caenorhabditis elegans

Ageing generates senescent pathologies, some of which cause death. Interventions that delay or prevent lethal pathologies will extend lifespan. Here we identify life-limiting pathologies in Caenorhabditis elegans with a necropsy analysis of worms that have died of old age. Our results imply the presence of multiple causes of death. Specifically, we identify two classes of corpse: early deaths with a swollen pharynx (which we call ‘P deaths’), and later deaths with an atrophied pharynx (termed ‘p deaths’). The effects of interventions on lifespan can be broken down into changes in the frequency and/or timing of either form of death. For example, glp-1 mutation only delays p death, while eat-2 mutation reduces P death. Combining pathology and mortality analysis allows mortality profiles to be deconvolved, providing biological meaning to complex survival and mortality profiles

Central Serous Chorioretinopathy, Corticosteroids, and Uveitis

Any patient with a diagnosis of central serous chorioretinopathy (CSCR) should be questioned to determine any recent corticosteroid use, as the poor visual outcome may be due to unrecognized corticosteroid use. Atypical forms of CSCR may be misdiagnosed as an inflammatory serous retinal detachment, mainly Vogt-Koyanagi-Harada disease. CSCR that develops in association with preexisting uveitis could be a challenging diagnosis as it might be misinterpreted as a worsening of the primary inflammatory condition. Failure to differentiate CSCR from retinal or choroidal inflammatory diseases may result in inappropriate use of corticosteroids, leading to exacerbation of the condition and permanent visual loss. Discontinuation of corticosteroids should be the first step in the treatment of CSCR associated with corticosteroid therapy, and the use of immunosuppressive or immunomodulatory drugs may be required to control systemic or ocular inflammatory disease. The prognosis is usually favorable, but persistent visual loss may occur