Skip to main content

Table 4 Comparison of ZN and CS methods for detection and grading of AFB in first-spot sputum specimens

From: Comparative evaluation of a two-reagent cold stain method with Ziehl-Nelseen method for pulmonary tuberculosis diagnosis

ZN; no. (%)/24
  Grade 3+ 2+ 1+ Scanty Negative Total
  3+ 5(1.4) 0(0) 0(0) 0(0) 0(0) 5(1.4)
  2+ 3(0.8) 8(2.2) 0(0) 0(0) 0(0) 11(3.0)
CS/23 1+ 0(0) 0(0) 6(1.7) 0(0) 0(0) 6(1.7)
  Scanty 0(0) 0(0) 0(0) 1(0.3) 0(0) 1(0.3)
  Negative 0(0) 0(0) 0(0) 1(0.3) 338(93.4) 339(93.6
  Total 8(2.2) 8(2.2) 6(1.7) 2(0.6) 338(93.4) 362(100)
  1. AFB acid fast bacilli; 3+ = More than 10 AFB per oil immersion field in at least 20 fields; 2+ = 1–9 AFB per oil immersion field in at least 50 fields; 1+ = 10–99 AFB in 100 oil immersion fields; Scanty = 1–9 AFB in 100 oil immersion fields.