The Epidemiological Profile and Predisposing Factors of Microbial Keratitis Over a 10-Year Period at a Tertiary Hospital in Central Saudi Arabia.

PURPOSE: To evaluate the demographic and predisposing factors and clinical presentation of microbial keratitis (MK) patients over 10 years at a tertiary hospital in central Saudi Arabia. METHOD: In 2020, a retrospective review of data from clinical and pathology departments from 2010 to 2019 was conducted. Demography includes age, gender, residence, and the risk factor of microbial keratitis, clinical features, and organism profile as number and percentage. RESULT: We reviewed 181 eyes of 179 patients with microbial keratitis. The mean age was 40.1 years. Contact lens usage (55; 30%), ocular trauma (30; 16.5%), and ocular surface diseases (42; 23.2%) were the main predisposing factors. Hypopyon was noted in 60 (33%) eyes, impaired vision at presentation was observed in 78 (43%) eyes, and endophthalmitis with microbial keratitis was noted in eight (4.4%) eyes at presentation. Ninety-eight (54,1%) cases were culture positive, while gram-positive organisms were seen in 50 (27.6%) eyes, gram-negative organisms in 35 (19.3%) patients, and fungi in 13 (7.2%) patients. Microbial keratitis was central in 67 (37%), paracentral in 94 (52%), and peripheral in 20 (11.3%) patients. All instances of fungal keratitis occurred in the eyes of men who work in the agriculture field. CONCLUSION: Standard operating procedures to manage microbial keratitis at primary and secondary eye care levels are recommended. Health promotion to prevent trauma, appropriate use of contact lens, and early treatment could prevent the incidence of microbial keratitis.

Characteristics and health risk assessment of heavy metal contamination from dust collected on household HVAC air filters.

Heavy metals associated with airborne particulate matter are detrimental to human health, but risk assessment is difficult due to the technical challenges of determining exposure rates. In houses and other buildings, the heating, ventilation and air conditioning (HVAC) system is equipped with an air filter that captures airborne particulate matter from the indoor air that enters the HVAC system. This study used the air filter dust as a proxy for the heavy metal exposure of children and adults, based on a household study in Kuwait. Air filter dust contained from 12.5 ± 5 mg Co/kg dust to 14 453 ± 5046 mg Fe/kg dust. Houses had high levels of Fe, Al, Zn, and Mn and relatively low concentrations of As and Co. Source apportionment revealed that metals in air filter dust were from natural and anthropogenic sources, including vehicular emissions, fossil fuel combustion, and metals-related industries. The total Hazard Index (HI; Σ exposure routes) for heavy metals was >1 for children and adults. Total cancer risks (TCR; Σ exposure routes) were 5.93 × 10-3 (95% CI: 5.28 × 10-3- 6.59 × 10-3) for children and 5.16 × 10-3 (95% CI: 4.59 × 10-3 - 5.73 × 10-3) for adults. Heavy metals, particularly the Cr and Pb concentrations, contribute to the non-carcinogenic and carcinogenic health risks of children and adults in Kuwait households.

Human health risks from brominated flame retardants and polycyclic aromatic hydrocarbons in indoor dust.

Exposure to dust particles containing toxic compounds is linked to serious health outcomes, including cancer. The purpose of this study was to determine if indoor dust from houses and cars contained harmful levels of brominated flame retardants (polybrominated diphenyl ethers, PBDEs) and polycyclic aromatic hydrocarbons (PAHs), and to assess their potential toxicity to adults and children. In Kuwait, the median concentration of total PBDEs (Æ©14- PBDEs) was 408.55 µg PBDEs/kg dust in houses and twice as high in cars (838.52 µg PBDEs/kg dust), while total PAHs (Æ©16-PAHs) were similar in houses (992.81 µg PAHs/kg) and cars (900.42 µg PAHs/kg). The PBDEs and PAHs concentrations in indoor dust were related to house age and square footage, car model year, and natural ventilation. Furthermore, a higher PBDEs concentration was associated with electronic devices that operate continuously, furniture containing foam treated with PBDEs, and cars that are parked outdoors, since PBDEs tend to be volatilized under these conditions. The PAHs concentration in indoor dust increased with smoking and proximity to major roads and industrial facilities, which are major PAHs sources. The hazard quotient and total cancer risk for PBDEs in indoor dust were within safe limits, but indoor dust with higher PAHs concentrations had hazard quotients from 5.51 to 11.23 and total cancer risk of 10-3 for adults and children. We conclude that exposure to PAHs-contaminated indoor dust from houses and cars where smoking occurs can increase the cancer risk of adults and children.

Modeling gaseous emissions and dispersion of two major greenhouse gases from landfill sites in arid hot environment.

As waste production exponentially increases, landfill continues to be the common method of waste disposal. Landfills represent significant anthropogenic sources of methane (CH4) and carbon dioxide (CO2); the main constituents of greenhouse gases (GHGs) resultant from microbial decomposition of organic waste. In the present study, ISC-AERMOD dispersion model was employed to estimate the release and dispersion rates of CH4 and CO2 from major landfill sites across Kuwait under different seasonal conditions. Results revealed that dispersions of CH4 and CO2 were influenced by the dominant northwestern and southeastern wind directions and thus, the dispersion of CH4 and CO2 extended predominantly toward northeastern direction. In terms of seasonal variation, the maximum concentrations of CH4 and CO2 were detected in winter and spring seasons, close to the landfill zone, and the dispersion of CH4 and CO2 fluxes during winter and spring seasons was longer than that during summer and fall seasons. Consequently, residential areas close to the disposal sites were exposed to higher concentrations of CH4 and CO2 gases during winter and spring. The findings of this study can serve as the basis for selecting suitable landfill locations under desert climatic conditions as determined by the distances over which gaseous emissions can diffuse.

Health risks associated with the polycyclic aromatic hydrocarbons in indoor dust collected from houses in Kuwait.

Polycyclic aromatic hydrocarbons (PAHs) are a byproduct of combustion processes. They are common pollutants in oil-producing countries because fossil fuel processing generates PAHs that associate with dust. Airborne particles containing PAHs are transported into houses during dust storms, which are common in the arid oil-producing countries, and consequently the children and adults in the household are exposed to PAHs in indoor house dust. The goal of this study was to present a systematic survey of PAHs in indoor house dust in Kuwait. The PAHs concentrations and composition of indoor house dust was determined, along with their probable source and the potential carcinogenic risks. Total PAHs concentrations (Æ©PAH) were, on average (±standard deviation) 1112 ± 347 µg/kg and ranged from 450 to 2242 µg/kg. Heavier congeners (4-6 ring PAHs) represented 61% of the Æ©PAH. Petroleum combustion and traffic emissions were the major source of PAHs, based on the isomeric ratios of PAHs in indoor house dust. The incremental lifetime cancer risks (ILCRs) of exposure to PAHs in indoor house dust was 2.23 × 10-3 (95% CI: 1.99 × 10-3 - 2.48 × 10-3) for children and 2.15 × 10-3 (95% CI: 1.94 × 10-3 - 2.37 × 10-3) for adults, exceeding the US EPA safe limit of 1 × 10-6. Therefore, exposure to PAHs present in indoor house dust increases the cancer risk for children and adults in Kuwait.

Demography and diagnosis of patients encountered at Qassim University Polyclinics, Central Saudi Arabia.

OBJECTIVES: To provide current data on the demography and diagnosis of patients encountered at the Internal Medicine Outpatient Department of Qassim University Polyclinics (QUP), Qassim, Kingdom of Saudi Arabia (KSA).  METHODS: A cross-sectional descriptive study conducted at QUP, Qassim, KSA, during the period November 2014 and December 2015. The record files of the study patients who were sampled by convenience method, were reviewed and analyzed. A standardized questionnaire was designed by the authors to collect data from the patients' records. Percentage descriptive statistics were used for data analysis.   RESULTS: A total of 115 patients were studied. Males were 61.8%. The age range was 1.5-83 years (mean 42.3). The predominant age group was 31-60 years (59.4%). The identified top 5 diseases were: hypertension 40 (34.7%), diabetes mellitus 39 (33.9%), dyslipidemia 17 (14.7%), vitamin D deficiency 13 (11.3%), and arthritic disease 6 (5.2%).  CONCLUSION: Non-communicable diseases, in the present study, were the common causes for patients to attend QUP, Qassim, KSA. Changing lifestyle of the population is one possible explanation for such a trend. Prospective studies are advisable toward an in-depth understanding of this trend.