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Table 2 Results of routine TB diagnostic tests, Xpert Ultra and the MPT64 test performed on samples

From: Diagnosis of extrapulmonary tuberculosis using the MPT64 antigen detection test in a high-income low tuberculosis prevalence setting

  Positive samples/total samples (%)
 Number of casesMicro-scopyaCulture1-step PCRNested-PCRXpert UltraMPT64 test
TB cases
 All samples316/27 (22)16/26 (62)6/18 (33)7/11 (64)4/7 (57)10/31 (32)
  Lymph node biopsies71/6 (17)2/6 (33)0/5 (0)2/2 (100)N/A3/7 (43)
  Other biopsies122/9 (22)5/8 (63)1/7 (14)4/6 (67)N/A4/12 (33)
  Pus samples20/2 (0)1/2 (50)1/1 (100)N/A1/2 (50)1/2 (50)
  Lymph node aspirates73/7 (43)5/7 (71)4/4 (100)1/3 (33)3/4 (75)2/7 (29)
  Fluid samples30/3 (0)3/3 (100)0/1 (0)N/A0/1 (0)0/3 (0)
 Confirmed TB case -confirmed sample22b5/19 (26)16/17 (94)6/13 (46)7/9 (78)4/5 (80)8/22 (36)
  Culture positive sample164/16 (25)16/16 (100)5/12 (42)2/4 (50)4/5 (80)3/16 (19)
  Culture positive, PCR positive sample63/6 (50)6/6 (100)5/5 (100)2/2 (100)3/3 (100)3/6 (50)
  Culture positive, PCR negative sample81/8 (13)8/8 (100)0/7 (0)0/2 (0)1/2 (50)0/8 (0)
  1-step PCR positive sample64/6 (67)5/6 (83)6/6 (100)1/1 (100)3/3 (100)4/6 (67)
  Nested-PCR positive sample71/4 (25)2/2 (100)1/1 (100)7/7 (100)1/1 (100)5/7 (71)
Confirmed TB case -unconfirmed sample40/3 (0)0/4 (0)0/3 (0)N/AN/A2/4 (50)
Clinically diagnosed TB case51/5 (20)0/5 (0)0/2 (0)0/2 (0)0/2 (0)0/5 (0)
Non-TB cases
 All samples2437/139 (5)0/226 (0)0/40 (0)0/24 (0)1/41 (2)39/243 (16)
  Lymph node biopsies17c1/13 (8)0/14 (0)0/4 (0)0/4 (0)0/2 (0)0/17 (0)
  Other biopsies52d2/35 (6)0/40 (0)0/16 (0)0/17 (0)1/8 (13)1/52 (2)
  Pus samples13e3/13 (23)0/13 (0)0/4 (0)0/1 (0)0/8 (0)4/13 (31)
  Lymph node aspirates4f1/2 (50)0/2 (0)0/2 (0)0/2 (0)0/1 (0)2/4 (50)
  Fluid samples1570/76 (0)0/157 (0)0/14 (0)N/A0/22 (0)32/157 (20)
  1. Abbreviations: TB, tuberculosis; PCR, polymerase chain reaction
  2. aMicroscopy performed at microbiology laboratory and/or pathology laboratory. A sample with discordant microscopy results between the laboratories (n = 2) is registered as microscopy positive
  3. bOne of the nested-PCR positive patients was not started on TB treatment, and only followed by controls
  4. c6 cases of NTM infection (2 NTM culture positive, 1 NTM specific PCR positive, 3 given a clinical diagnosis)
  5. d2 cases of NTM infection (2 NTM specific PCR positive)
  6. e3 cases of NTM infection (3 microscopy and NTM culture positive)
  7. f1 case of NTM infection (microscopy, NTM culture and NTM specific PCR positive. This case was also MPT64 positive)