Clinical and epidemiological features of tuberculosis isolated from critically ill patients

Specific Mycobacterium tuberculosis Strain Circulating in Prison Revealed by Cost-Effective Amplicon Sequencing

“…The results obtained indicate that, within the PDL population, 39% of strains were identified as LAM (lineage 4.3), 34% as X (lineage 4.1.1), 25% as Haarlem (lineage 4.1.2.1), and 2% as S (lineage 4.4.1.1) (Figure 1). The distribution of lineages contrasts with that observed in community isolates (data obtained from previous work [11]). In particular, the X strain is overrepresented in PDL (chi-square with p-value = 0.0001).…”

“…In particular, the X strain is overrepresented in PDL (chi-square with p-value = 0.0001). This lineage was not detected in any isolates from patients admi9ed to intensive care units and is detected in very low percentages in community isolates (around 1%) [11]. It was also not observed in drug-resistant strains previously characterized by our group [23].…”

“…observed in community isolates (data obtained from previous work [11]). In particular, the X strain is overrepresented in PDL (chi-square with p-value = 0.0001).…”

“…While PDLs are recognized by the World Health Organization (WHO) as a highrisk population for tuberculosis, global data on tuberculosis cases among PDLs are not systematically gathered [3]. In Latin America, reports on tuberculosis in prisons are scarce, with a majority of these from Brazil [4][5][6][7][8][9][10][11]. In Uruguay, where this study was performed, the available data indicate an incidence rate of 887/100,000 PDL (23.3 times greater than in the general population, in line with the reported data [2]) (https://chlaep.org.uy/programanacional-de-control-de-tuberculosis/dia-de-la-tuberculosis-2023/ accessed on 4 May 2024).…”

“…The SNP-based approach allows us to amplify eleven regions containing characteristic lineage SNPs and nine genes associated with anti-tuberculosis drugs using two simple PCR pool reactions, at an affordable cost for the public system. With this approach, we identified a specific lineage (lineage X) circulating among PDL that is not present in the general population [11]. Interestingly, all the cases detected upon entry into the prison system with the X lineage had a previous history of incarceration.…”