No abstract

Diagnosis of lung tuberculosis is possible with two spot sputum samples with modified ZN staining.

A method was devised to measure the work of adhesion (WA) to a substrate of mucus, a viscoelastic gel, from the measured contact angle of glycerol on a mucus substrate and the known physical properties of a Teflon surface. Fifteen sputum samples from cystic fibrosis (CF) patients were compared with 25 mucus samples from canine tracheal pouches (CP), studied in the hydrated and partially dehydrated states. Apparent viscosity (eta A) and recoverable shear strain (SR) were measured by fluxgate magnetometry, and water content was inferred from vapor pressure osmometry. Na+, K+, and Ca2+ concentrations were measured with specific ion electrodes and Cl- with a chloridimeter. The Cl- concentration of the CP mucus was inversely proportional to its osmolality, and the Cl- concentration of the CP mucus was 102.5 +/- 1.6 meq/l compared with 55.6 +/- 2.5 meq/l for CF sputum. When CP mucus osmolality was increased from 316.0 +/- 5.5 to 430.0 +/- 7.5 mosmol/kg, WA increased from 25.1 +/- 1.8 to 31.1 +/- 1.2 ergs/cm2 and eta A increased from 391 +/- 55 to 622 +/- 121 P, respectively. CF sputum WA was 30.2 +/- 0.6 ergs/cm2, eta A was 1,110 +/- 316 P, and osmolality was 466.0 +/- 14.0 mosmol/kg. The increased WA and eta A of mucus in CF patients may thus be dependent on the hydration of mucus, which is related to the documented Cl- transport defect.

Background:Sputum smear microscopy is the main tool for the diagnosis of pulmonary tuberculosis (TB), especially in low- and middle-income countries (LMICs). Limited sensitivity of smear microscopy and patient dropouts (PDs) are the important obstacles of national TB control programs.Objectives:(1) To assess the diagnostic utility of the same day (SS2) approach (2) To compare the smear results of the spot morning (SM) and the SS2 approaches.Materials and Methods:The study was conducted in the Department of Microbiology, GSL Medical College, Rajahmundry, Andhra Pradesh, India from January 2011 to February 2015. Three sputum samples were collected [spot (S), second spot (S2) 1 h after S, and morning sample (M)] from the volunteers. The sputum smears were stained by Ziehl-Neelsen (ZN), modified ZN (MZN), and fluorescent staining (FS) techniques and the results were pooled and compared under SM and SS2 approaches.Results:Of the 3,186 study participants, sputum smear positivity (SSP) for SM approach was 9.6% and 10.8% and for SS2 approach, it was 9.4% and 10.6%, respectively, with ZN and FS and the results were statistically insignificant (Mann-Whitney U test, P > 0.05).Conclusion:Technically SSP was similar for both the approaches and no improvement was observed with the SS2 approach. Hence, there is an urgent need to improve SSP.

Nil dropouts and patient convenience are the added advantages of using same-day smears, and the concentration method improved smear positivity. Given these advantages, using same-day smears with the concentration method should be considered by the World Health Organization and India's Revised National Tuberculosis Control Programme.