Barbieri RR, Manta FSN, Moreira SJM, Sales AM, Nery JAC, Nascimento LPR, Hacker MA, Pacheco AG, Machado AM, Sarno EM, Moraes MO. Quantitative polymerase chain reaction in paucibacillary leprosy diagnosis: A follow-up study.
PLoS Negl Trop Dis 2019;
13:e0007147. [PMID:
30835722 PMCID:
PMC6428338 DOI:
10.1371/journal.pntd.0007147]
[Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 03/21/2019] [Accepted: 01/09/2019] [Indexed: 02/01/2023] Open
Abstract
OBJECTIVE
The diagnosis of paucibacillary (PB) leprosy cases remains a challenge because of the absence of a confirmatory laboratory method. While quantitative polymerase chain reaction (qPCR) has been shown to provide reliable sensitivity and specificity in PB diagnoses, a thorough investigation of its efficacy in clinical practice has not yet been published. The present study evaluated patients with suspected leprosy skin lesions by using qPCR to identify PB individuals in the Leprosy Outpatient clinic at the Oswaldo Cruz Foundation in Rio de Janeiro, Brazil.
METHODS
One hundred seventy-two suspected PB cases were included in the study. The patients were evaluated by a dermatologist at three different times. The clinical dermato-neurological examination and collected samples were performed on the first visit. On the second visit, the results of the histopathological analysis and PCR assay (DNA-based Mycobacterium leprae qPCR-targeting 16S gene) results were analyzed, and a decision regarding multi-drug therapy was made. A year later, the patients were re-examined, and the consensus diagnosis was established.
RESULTS
In 58% (100/172) of cases, a conclusive diagnosis via histopathological analysis was not possible; however, 30% (30/100) of these cases had a positive PCR. One hundred ten patients (110/172) attended the third visit. The analysis showed that while the sensitivity of the histopathological test was very low (35%), a qPCR alone was more effective for identifying leprosy, with 57% sensitivity.
CONCLUSION
The use of qPCR in suspected PB cases with an inconclusive histology improved the sensitivity of leprosy diagnoses.
Collapse