Fig 1.
Clinical evaluations of the cases.
A clinical evaluation and sample collection at the first visit; the histopathological and PCR results and the decision on pursuing MDT in the second; the consensus diagnosis in the third visit one year after the second.
Table 1.
Clinical-epidemiological characteristics: N = 172.
Table 2.
Proportions for histological diagnosis and polymerase chain reaction results.
Fig 2.
Flow chart of quantitative polymerase chain reaction results, histopathological results, and consensus diagnosis.
The 21 underlined patients had exhibited the histological features of other dermatoses or NSHFs, and the consensus diagnosis was leprosy (L). These cases were diagnosed by PCR. The five highlighted cases were false PCR positives. L = consensus diagnosis of leprosy; NL = consensus diagnosis of non-leprosy.
Fig 3.
Examples of cases diagnosed as other dermatoses via histology and for which polymerase chain reaction was decisive in the leprosy diagnosis.
All the cases were qPCR positive. Case I: (A) before multi-drug therapy (MDT), (B) one year after MDT; (C) histology: hematoxilin-eosin (H.E.) 10X, granulomatous rosacea: nerve bundles with normal appearance and granulomas attached to adnexa; Case II: (D) before MDT, (E) 8 months after MDT, (F) histology: H.E. 20X, suggestive of eczema; Case III: (G) before MDT, (H) residual lesion at release from treatment, (I) histology: H.E. 10X, nonspecific infiltrated inflammatory; Case IV: (J) before MDT, (K) one year after the end of MDT, (L) histology: HE 10X, granuloma annulare.
Table 3.
Histological and quantitative polymerase chain reaction (qPCR) sensitivity, specificity, and accuracy, and the combination of these two diagnostic methods.