A Case of Sarcoidosis Mimicking Lymphoma Confounded by Cognitive Decline.

Sarcoidosis is a disease with an unknown cause that affects multiple organ systems and has a varied clinical presentation. Often, its symptomatology mimics other disease processes, such as lymphoma, tuberculosis, and amyloidosis. The reticuloendothelial involvement and typical B symptoms of weight loss, fatigue, night sweats, and lymphadenopathy can make sarcoidosis often easily confused with lymphoma. Sarcoidosis has a myriad of central nervous system (CNS) effects, which are often not recognized as symptoms of the disease. These neuropsychiatric symptoms can include, but are not limited to, cognitive decline, headaches, and personality changes. In this report, we discuss a case of a patient who presented with symptoms consistent with indolent lymphoma but was eventually diagnosed with sarcoidosis with extrapulmonary manifestations.

Shared air: a renewed focus on ventilation for the prevention of tuberculosis transmission.

BACKGROUND: Despite an improvement in the overall TB cure rate from 40-74% between 1995 and 2011, TB incidence in South Africa continues to increase. The epidemic is notably disquieting in schools because the vulnerable population is compelled to be present. Older learners (age 15-19) are at particular risk given a smear-positive rate of 427 per 100,000 per year and the significant amount of time they spend indoors. High schools are therefore important locations for potential TB infection and thus prevention efforts. METHODS AND FINDINGS: Using portable carbon dioxide monitors, we measured CO2 in classrooms under non-steady state conditions. The threshold for tuberculosis transmission was estimated using a carbon dioxide-based risk equation. We determined a critical rebreathed fraction of carbon dioxide (ƒ(c)) of 1 · 6%, which correlates with an indoor CO2 concentration of 1000 ppm. These values correspond with a ventilation rate of 8 · 6 l/s per person or 12 air exchanges per hour (ACH) for standard classrooms of 180 m(3). CONCLUSIONS: Given the high smear positive rate of high-school adolescents in South Africa, the proposal to achieve CO2 levels of 1000 ppm through natural ventilation (in the amount 12 ACH) will not only help achieve WHO guidelines for providing children with healthy indoor environments, it will also provide a low-cost intervention for helping control the TB epidemic in areas of high prevalence.

Quantification of shared air: a social and environmental determinant of airborne disease transmission.

BACKGROUND: Tuberculosis is endemic in Cape Town, South Africa where a majority of the population become tuberculosis infected before adulthood. While social contact patterns impacting tuberculosis and other respiratory disease spread have been studied, the environmental determinants driving airborne transmission have not been quantified. METHODS: Indoor carbon dioxide levels above outdoor levels reflect the balance of exhaled breath by room occupants and ventilation. We developed a portable monitor to continuously sample carbon dioxide levels, which were combined with social contact diary records to estimate daily rebreathed litres. A pilot study established the practicality of monitor use up to 48-hours. We then estimated the daily volumes of air rebreathed by adolescents living in a crowded township. RESULTS: One hundred eight daily records were obtained from 63 adolescents aged between 12- and 20-years. Forty-five lived in wooden shacks and 18 in brick-built homes with a median household of 4 members (range 2-9). Mean daily volume of rebreathed air was 120.6 (standard error: 8.0) litres/day, with location contributions from household (48%), school (44%), visited households (4%), transport (0.5%) and other locations (3.4%). Independent predictors of daily rebreathed volumes included household type (p = 0.002), number of household occupants (p = 0.021), number of sleeping space occupants (p = 0.022) and winter season (p<0.001). CONCLUSIONS: We demonstrated the practical measurement of carbon dioxide levels to which individuals are exposed in a sequence of non-steady state indoor environments. A novel metric of rebreathed air volume reflects social and environmental factors associated with airborne infection and can identify locations with high transmission potential.