Corrigendum

Following the publication of the Special Report by Matteelli A, Richardson M, Sotgiu G, Centis R and Migliori GB ‘Multidrug- and extensively drug-resistant TB in persons living with HIV’, published in the June 2009 issue of Expert Review of Respiratory Medicine (Expert Rev. Resp. Med. 3[3], 245–254 [2009]), it has been brought to our attention that the following table on page 250 was incorrectly printed as:

Table 1. Characteristics of the most important techniques used for detecting drug resistance.

Method	Description	Advantages	Disadvantages	Sensitivity/specificity (%)	Turnaround time
DNA sequencing	To characterize mutations (mainly rpoB gene) for rifampicin	Accuracy	High cost; several reactions	97/100	16 days
Line probe assay	To detect rifampicin resistance (rpoB gene)	Relatively simple; high correlation with DNA sequencing and conventional tests; high sensitivity and specificity	Basic expertise in molecular biology required; sensitivity depends on the amount of DNA and the presence of inhibitors	82.2/66.7 (compared with conventional tests) 100/96.9 (detection of rifampicin resistance)	6 h–2 days
GenoType MTBDR assay	To simultaneously detect isoniazid and rifampicin resistance (rpoB and katG genes)	Relatively simple; high correlation with DNA sequencing and conventional tests; high sensitivity and specificity	Basic expertise in molecular biology required; sensitivity depends on the amount of DNA and the presence of inhibitors	98.1/98.7 (detection of rifampicin resistance) 84.3/99.5 (detection of isoniazid resistance)	6 h–2 days
Microarrays	To mainly detect resistance to rifampicin	Speed of the tests (within 12 h)	High cost	80/100	<12 h
Real-time PCR techniques	Rapid detection of drug resistance	Speed of the test (1.5–2 h after DNA extraction); lower risk of contamination; application directly in clinical samples	High cost (equipment and reagents); basic expertise in molecular biology required	78/100	1.5–2 h
MGIT system	Drug resistance	High correlation with conventional tests	High cost	100/98.6	10–22 days
LiPA assay for fluoroquinolone resistance	To detect fluoroquinolone resistance	Extensively drug-resistant-TB cases	Low specificity	90/100	A few hours to 2 days

The correct table is shown overleaf:

Table 1. Characteristics of the most important techniques used for detecting drug resistance.

Method	Description	Advantages	Disadvantages	Sensitivity/specificity (%)	Turnaround time
DNA sequencing	To characterize mutations (mainly rpoB gene) for rifampicin	Accuracy	High cost; several reactions	97/100	16 days
Line probe assay	To detect rifampicin resistance (rpoB gene)	Relatively simple; high correlation with DNA sequencing and conventional tests; high sensitivity and specificity	Basic expertise in molecular biology required; sensitivity depends on the amount of DNA and the presence of inhibitors	82.2/66.7 (compared with conventional tests) 100/96.9 (detection of rifampicin resistance)	6 h–2 days
GenoType MTBDR assay	To simultaneously detect isoniazid and rifampicin resistance (rpoB and katG genes)	Relatively simple; high correlation with DNA sequencing and conventional tests; high sensitivity and specificity	Basic expertise in molecular biology required; sensitivity depends on the amount of DNA and the presence of inhibitors	98.1/98.7 (detection of rifampicin resistance) 84.3/99.5 (detection of isoniazid resistance)	6 h–2 days
Microarrays	To mainly detect resistance to rifampicin	Speed of the tests (within 12 h)	High cost	80/100	<12 h
Real-time PCR techniques	Rapid detection of drug resistance	Speed of the test (1.5–2 h after DNA extraction); lower risk of contamination; application directly in clinical samples	High cost (equipment and reagents); basic expertise in molecular biology required	78/100	1.5–2 h
MGIT system	Drug resistance	High correlation with conventional tests	High cost	100/98.6	10–22 days
LiPA assay for fluoroquinolone resistance	To detect fluoroquinolone resistance	Extensively drug-resistant-TB cases	Low sensitivity	90/100	A few hours to 2 days

The authors and editors of Expert Review of Respiratory Medicine would like to sincerely apologize for any inconvenience or confusion this may have caused our readers.