Pulmonary tuberculosis, impaired lung function, disability and quality of life in a high-burden setting.

SETTING: Tuberculosis treatment clinic in Papua, Indonesia. OBJECTIVE: To document the impact of pulmonary tuberculosis (PTB) on lung function, exercise tolerance and quality of life (QOL). DESIGN: A prospective cohort study of 115 patients with smear-positive PTB followed for 6 months. Demographics, disease history, sputum microbiology, spirometry, 6-minute weight.walk distance (6MWWD) and QOL (modified St George's Respiratory Questionnaire) were measured at diagnosis and at 2 and 6 months. Analysis was restricted to the 69/115 (60%) subjects who attended all follow-up visits. RESULTS: Subjects who attended all visits were less likely than the full cohort to be of Papuan ethnicity (P < 0.05), were more likely to be cured (P < 0.001) and had better lung function at diagnosis (P < 0.05). Significant lung function impairment (forced expiratory volume in 1 second [FEV(1)] <60% predicted) was found in 27/69 (39%) at diagnosis. Although this fell during treatment (P < 0.01), 17/69 (24.6%) had persisting significant lung function impairment at treatment completion. As lung function recovered, exercise tolerance (6MWWD) rose by 12.3% (P < 0.001) and QOL improved (P < 0.001). CONCLUSION: In a high-burden setting, PTB causes prolonged, significant impairment of lung function, exercise tolerance and QOL. Current measures of disease burden are likely to underestimate the true impact of disease. Earlier diagnosis and disease-modifying treatments may reduce the long-term impact of PTB.

An assay combining cell culture with reverse transcriptase PCR to detect and determine the infectivity of waterborne Cryptosporidium parvum.

The presence of Cryptosporidium in drinking water supplies is a significant problem faced by the water industry. Although a variety of methods exist for the detection of waterborne oocysts, water utilities currently have no way of assessing the infectivity of detected oocysts and consequently are unable to accurately determine the risks posed to public health by waterborne Cryptosporidium. In this paper, the development of an infectivity assay for waterborne Cryptosporidium parvum is described. Oocysts were inoculated onto monolayers of Caco-2 cells and grown on microscope slides, and infections were detected by C. parvum specific reverse transcriptase PCR of extracted mRNA, targeting the heat shock protein 70 (hsp70) gene. A single infectious oocyst was detected by this experimental procedure. The use of concentrated samples obtained from 250 liters of finished water had no observable effect on the integrity of cell monolayers or on the infectivity of oocysts seeded into the concentrate. Intracellular developmental stages of the parasite were also detected by using fluorescently labeled antibodies. One pair of PCR primers targeting the hsp70 gene was specific for C. parvum, while a second pair recognized all species of Cryptosporidium tested. The C. parvum-specific primers amplified DNA from 1 to 10 oocysts used to seed 65 to 100 liters of concentrated environmental water samples and were compatible with multiplex PCR for the simultaneous detection of C. parvum and Giardia lambia. This paper confirms the utility of PCR for the detection of waterborne C. parvum and, most importantly, demonstrates the potential of an in vitro infectivity assay.