Table 2.
Summary of studies that use qPCR in diagnosis of PKDL, including those that use qPCR during follow-up.
| References | Method | Tissue obtained by | PKDL type | No tested | Result |
|---|---|---|---|---|---|
| Ramesh et al., 2011 | qPCR | Biopsy before treatment | Macular (2), indurated (11) polymorphic (13) | 26 | Range: 3–240,000 parasites/μg tissue DNA; median 667 |
| Biopsy after treatment | 15 | All negative | |||
| Ramesh et al., 2015b | qPCR | Slit aspirate | Pretreatment parasite load: | ||
| Polymorphic | 59 | • In 62 who were cured: 2302 parasites/μL slit aspirate | |||
| Macular | 14 | • In 11 who relapsed: 11842 parasites/μL slit aspirate | |||
| After treatment | |||||
| All | 30 | • 26 negative | |||
| • 2 <10 parasites/μL slit aspirate and were cured | |||||
| • 2 <10 parasites/μL slit aspirate and relapsed | |||||
| Verma et al., 2013b | qPCR | Slit aspirate | All types | 50 | Range 4–70740/μL slit aspirate |
| Nodular | 26 | Mean 9790 parasites/μL slit aspirate | |||
| Papular/macularIn those who in slit aspirate are | 24 | Mean 427 parasites/μL slit aspirate | |||
| • Microscopy positive | 30 | Mean 8205 parasites/μL slit aspirate | |||
| • Microscopy negative | 20 | Mean 932 parasites/μL slit aspirate | |||
| In those who in biopsy are | |||||
| • Microscopy positive | 15 | Mean 15925 parasites/μL slit aspirate | |||
| • Microscopy negative | 31 | Mean 791 parasites/μL slit aspirate | |||
| 1 month after treatment | 17 | Negative | |||
| 2 | 7 and 8 parasites/μL slit aspirate, 1 relapsed after 1 year | ||||
| Hossain et al., 2017 | qPCR Leishmania-nested PCR (Ln-PCR) | Biopsy before treatment | Macular | 38 | qPCR: positive 34/40; sensitivity 85% (95% CI, 70.2–94.3) |
| Papular | 2 | Ln-PCR: positive 21/40; sensitivity 52.5 % (95% CI 36.1–68.5) | |||
| Pretreatment parasite load by qPCR: | |||||
| • Range 1.38–4065.89 parasites/μg tissue DNA | |||||
| • Mean 295.46 parasites/μg tissue DNA | |||||
| Biopsy after treatment | 40 | After treatment | |||
| • 3 remained positive in qPCR | |||||
| • 1 remained positive in Ln-PCR | |||||
| Ghosh et al., 2018 | qPCR | Biopsy | Macular | 91 | positive 83; sensitivity 91.2% (83.4–96.1%) |
| Microscopy | Biopsy | Macular | 91 | positive 46; sensitivity 50.6% (39.9%–61.2%) | |
| Buffy coat | Blood | Macular | 91 | all negative | |
| qPCR | biopsy | In those who are | |||
| • Microscopy positive | 46 | IQR 9.19 (3.61–45.41)/μg tissue DNA median per μg tissue DNA* | |||
| • Grade 1: 7.56 (4.5–71.22) | |||||
| • Grade 2: 8.22 (2.09–33.42) | |||||
| • Grade 3: 22.06 (3.9–43.02) | |||||
| • Microscopy negative | 45 | IQR 15.3 (2.99–64.7)/μg tissue DNA | |||
| qPCR | Buffy coat | Healthy controls | 86 | All negative | |
| Moulik et al., 2018 | qPCR | Biopsy before treatment | All | 184 | Median IQR 5229 (896–50898)/μg genomic DNA |
| Macular | 91 | Median IQR 3665 (615–21528)/μg gDNA | |||
| Polymorphic | 93 | Median IQR 18620 (1266–93934)/μg gDNA | |||
| Biopsy after treatment | |||||
| • With miltefosine (3 m) | Macular | 17 | <10/μg gDNA | ||
| Polymorphic | 21 | <10/μg gDNA | |||
| • With LAMB after | |||||
| ° 3 wks | Macular Polymorphic |
34 36 |
2128 (544–5763)/μg gDNA 2541 (650–9073)/μg gDNA |
||
| ° 6 months | All | 38 | 5665 (1840-17067/μg gDNA | ||
| Bhargava et al., 2018 | Threshold to detect parasites by | (Macular 4, papular 20, nodular 26) | |||
| Microscopy | SSS | 4 parasites/μL SSS | |||
| qPCR | SSS | 60 parasites /μL SSS | |||
| Microscopy | Biopsy | 63 parasites/μg tissue DNA | |||
| qPCR | Biopsy | 502 parasites /μg tissue DNA |
*
Number of parasites detected by microscopy: grade 1: 1–10 per 1,000 fields; grade 2: 1–10 per 100 fields; grade 3: 1–10 per 10 fields. Difference not significant (p = 0.2457).