Causes of blindness at Nkhoma Eye Hospital, Malawi.

PURPOSE: The majority of blindness in Sub-Saharan Africa is treatable. This hospital-based study was undertaken in order to investigate the etiology of blindness at Nkhoma Eye Hospital, Malawi. METHODS: One ophthalmologist examined 2082 consecutive new patients who presented to the outpatient department at Nkhoma Eye Hospital, Malawi in 2006. Data recorded included age, sex, visual acuity and diagnosis. Patients were classified as blind if their best corrected visual acuity was <3/60 in one eye (unilateral) or two eyes (bilateral). RESULTS: The most common diagnosis in new outpatients was cataract (52.8%), followed by glaucoma (8.1%), corneal pathology (7.2%), uveitis (4.5%) and maculopathy (3.2%). There were 742 (35.6%) patients with unilateral blindness and 331 (15.9%) patients with bilateral blindness. Unilateral blindness was present in 37.4% of males and 26.5% of females. The most common causes of unilateral blindness were lens pathology (57.8%), followed by glaucoma (12.1%), corneal pathology (10.0%) and uveitis (6.1%). Bilateral blindness was present in 12.5% of males and 16.8% of females respectively. The most common causes of bilateral blindness were lens pathology (54.4%), followed by glaucoma (19.9%), retinopathy (3.6%), maculopathy (3.6%), uveitis (3.6%) and corneal pathology (3.3%). CONCLUSIONS: Cataract is the most common cause of blindness in Nkhoma. Resultantly, cataract management is preferentially targeted in the Nkhoma VISION2020 Programme. Training of auxiliary eye personnel in cataract diagnosis and surgery may assist in this approach.

Risk factors for mortality in Clostridium difficile infection in the general hospital population: a systematic review.

BACKGROUND: Clostridium difficile infection (CDI) is one of the most important healthcare-associated infections, causing considerable mortality. Numerous severity scores have been proposed to identify patients with CDI at risk of mortality, but a systematic review of the evidence upon which these are based has never been published. Such a review could permit future development of scores that better predict mortality. AIM: A systematic review of the published literature investigating clinically useful risk markers for mortality in CDI. METHODS: We searched MEDLINE 1950 to present, Web of Science with conference proceedings 1899 to present and BIOSIS Citation Index 1969 to present using PubMed and Web of Knowledge. Potential risk markers that had been evaluated by at least four studies were extracted. FINDINGS: Twenty-six studies, of 1617 initially identified, met inclusion criteria. The majority were retrospective cohort studies, mostly based in the USA. Older age, higher white blood cell count (WBC), higher creatinine level, lower albumin levels and, to a lesser extent, corticosteroid use were most frequently associated with mortality. Presence of fever, haemoglobin/haematocrit level, diarrhoea severity, presence of renal disease, diabetes, cancer, or nasogastric tube use did not appear to be associated with mortality. CONCLUSION: Our results support the use of age, WBC, serum creatinine, serum albumin level and possibly pre-existing corticosteroid use as potentially useful risk markers for mortality in CDI. Our results do not support the use of fever, haemoglobin/haematocrit, diarrhoea severity and several comorbidities as useful risk markers, raising questions about their inclusion in CDI severity scores.

Age over 80 years is not associated with increased hemorrhagic transformation after stroke thrombolysis.

Thrombolysis trials have recruited few patients aged ≥80 years, which has led to uncertainty about the likely risk-to-benefit profile in the elderly. Leukoaraiosis (LA) has been associated with hemorrhagic transformation (HT) and increases with advanced age. We tested whether there were any independent associations between age, LA and HT. Consecutive patients treated with intravenous (IV) tissue plasminogen activator (tPA) were identified from a prospective database. LA on baseline CT scans was assessed by two independent raters using the modified Van Swieten Score (mVSS) (maximum score 8, severe >4). HT was assessed on routine 24 hour to 48 hour CT /MRI scans using the European Cooperative Acute Stroke Study criteria for hemorrhagic infarct (HI) or parenchymal hematoma (PH) and judged symptomatic by the treating neurologist as per Safe Implementation of Thrombolysis in Stroke criteria. There were 206 patients treated with IV tPA (mean age: 71.0 years; range: 24-92 years), of whom 65/206 (32%) were aged ≥80 years. Overall, HT occurred in 41/206 patients (20%), HI in 31, PH1 in four (one symptomatic) and PH2 in six (three symptomatic). Age was not associated with HT (any HT: odds ratio [OR]=1.01; 95% confidence interval [CI]=0.5-2.08; p=0.99; PH: OR=0.53; 95% CI=0.12-2.3; p=0.51). There was one patient with PH1 and one patient with PH2 in 65 patients ≥80 years, both asymptomatic. LA was present in 112/208 (54%), and severe in 16.5%. LA increased with age (p<0.001) but was not associated with PH (any LA: OR=0.83; 95% CI=0.25-2.8; p=0.99; severe LA: OR=0.54, 95% CI=0.09-3.5; p=0.99). Age ≥80 years or LA did not increase the risk of HT (including PH) after thrombolysis, although LA increased with age. Neither factor should exclude otherwise eligible patients from tPA treatment.

Distribution of conjunctival ultraviolet autofluorescence in a population-based study: the Norfolk Island Eye Study.

OBJECTIVE: The objective of this study was to describe the distribution of conjunctival ultraviolet autofluorescence (UVAF) in an adult population. METHODS: We conducted a cross-sectional, population-based study in the genetic isolate of Norfolk Island, South Pacific Ocean. In all, 641 people, aged 15 to 89 years, were recruited. UVAF and standard (control) photographs were taken of the nasal and temporal interpalpebral regions bilaterally. Differences between the groups for non-normally distributed continuous variables were assessed using the Wilcoxon-Mann-Whitney ranksum test. Trends across categories were assessed using Cuzick's non-parametric test for trend or Kendall's rank correlation τ. RESULTS: Conjunctival UVAF is a non-parametric trait with a positively skewed distribution. Median amount of conjunctival UVAF per person (sum of four measurements; right nasal/temporal and left nasal/temporal) was 28.2 mm(2) (interquartile range 14.5-48.2). There was an inverse, linear relationship between UVAF and advancing age (P<0.001). Males had a higher sum of UVAF compared with females (34.4 mm(2) vs 23.2 mm(2), P<0.0001). There were no statistically significant differences in area of UVAF between right and left eyes or between nasal and temporal regions. CONCLUSION: We have provided the first quantifiable estimates of conjunctival UVAF in an adult population. Further data are required to provide information about the natural history of UVAF and to characterise other potential disease associations with UVAF. UVR protective strategies should be emphasised at an early age to prevent the long-term adverse effects on health associated with excess UVR.