A real-time PCR for quantification of parasite burden and its correlations with clinical characteristics and anti-rKRP42 IgG level in cutaneous leishmaniasis in Sri Lanka

In visceral and mucocutaneous leishmaniasis, humoral immune response can reflect disease severity and parasite burden. Cutaneous leishmaniasis (CL) in Sri Lanka is caused by a usually visceralizing parasite, Leishmania donovani. We assessed the parasite burden (relative quantity-RQ) in 190 CL patients using quantitative real-time PCR (qPCR-with primers designed for this study) and smear microscopy, then correlated it with clinical parameters and IgG response. RQ of parasite DNA was determined with human-specific glyceraldehyde 3-phosphate dehydrogenase (GAPDH) as the internal control. The qPCR sensitivity was tested with serially diluted DNA from cultured L. donovani parasites. Smears were assigned a score based on number of parasites per high power field. Data from previous studies were used for comparison and correlation; nested Internal Transcribed Spacer 1 (ITS1) PCR as reference standard (RS) and IgG antibody titers to the Leishmania rKRp42 antigen as the immune response. The qPCR amplified and quantified 86.8% of the samples while demonstrating a fair and significant agreement with ITS1-PCR and microscopy. Parasite burden by qPCR and microscopy were highly correlated (r = 0.76; p = 0.01) but showed no correlation with the IgG response (r = 0.056; p = 0.48). Corresponding mean RQs of IgG titers grouped by percentiles, showed no significant difference (p = 0.93). Mean RQ was higher in early lesions (p = 0.04), decreased with lesion size (p = 0.12) and slightly higher among papules, nodules and wet ulcers (p = 0.72). Our study established qPCR's efficacy in quantifying parasite burden in Sri Lankan CL lesions but no significant correlation was observed between the parasite burden and host IgG response to the Leishmania rKRP42 antigen.

Efficacy and Feasibility of Short-Stretch Compression Therapy for Filarial Lymphedema in Sri Lanka

The WHO-recommended essential package of care (EPC) for filarial limb lymphedema consists of daily limb washing, entry lesion management, limb protection, exercises, and elevation. Decongestive therapy (DT) with compression bandaging by trained lymphedema therapists adds additional benefit but is unavailable for most in low- and middle-income countries (LMICs). To determine whether DT using self-adjustable, short-stretch compression garments (SSCG), prefitted using portable, three-dimensional infrared imaging (3DII), would be effective and feasible in LMIC settings, we conducted a pilot 6-week, interventional, single-group, open-label pilot study in Galle, Sri Lanka. Ten participants with Dreyer stage 3 lymphedema used SSCG for 2 weeks after a 4-week lead-in EPC period. Effect of EPC and compression on quality of life was assessed using the 12-item WHO Disability Assessment Schedule 2.0 (WHODAS 2.0). Median participant age was 73 years (range: 32-85 years). Median percent limb volume reduction due to compression was 11.3% (range: 1.1-27.2%). WHODAS 2.0 scores did not change significantly between enrollment and study end. Garment acceptability was high throughout the study. These results provide proof of concept for 3DII-enabled SSCG in LMICs where trained therapists for filarial lymphedema may not be available.

Development of a Highly Sensitive Nested PCR and Its Application for the Diagnosis of Cutaneous Leishmaniasis in Sri Lanka

The recent surge in cutaneous leishmaniasis (CL) in Sri Lanka has rendered clinical diagnosis difficult; thus, laboratory confirmation is indispensable. A modified (two novel inner primers to detect CL caused by Leishmania donovani) nested Internal Transcribed Spacer-1 (ITS1) PCR-Restriction Fragment Length Polymorphism (RFLP) method was developed and tested. The sensitivity of the modified nested PCR was tested using serial dilutions (103 to 10−2) of the DNA extract of a cultured L. donovani DD8 strain. Patients (n = 194) from Southern Sri Lanka were examined clinically, microscopically (Slit Skin Smear-SSS) and using the modified nested PCR. The modified nested PCR detected 2.55 fg of parasite DNA compared to ITS1 PCR (25 fg) and detected more cases than SSS (94.3% vs. 77.3%; p < 0.01). The RFLP pattern was L. donovani in all cases. The modified nested PCR performed well in clinically doubtful lesions (95% by PCR vs. 60% by SSS; p < 0.01), ulcerated nodules (91% vs. 71.8%; p < 0.01) and plaques (100% vs. 66.7%; p < 0.01). SSS demonstrated sensitivity (80.9%), specificity (81.8%), PPV (98.7%) and NPV (20.5%) against modified PCR. Low parasite loads and atypical lesions can be diagnosed by the proposed method with higher accuracy.

Lymphoedema and its management in cases of lymphatic filariasis: the current situation in three suburbs of Matara, Sri Lanka, before the introduction of a morbidity-control programme

Using in-depth interviews, information on the current state of lymphoedema management was collected from 101 cases of lymphatic filariasis with lymphoedema in three suburbs of Matara. The interviews were conducted prior to the introduction of a programme of community home-based care (CHBC) that incorporates modern lymphoedema-management strategies. Thirty-two of the interviewees had severe lymphoedema (of grade III or above). The male interviewees had significantly more entry lesions than the female. Most of the subjects had suffered from episodes of limb pain with fever, although the incidence of these episodes appeared unrelated to the severity of the lymphoedema. The frequency of the episodes of limb-pain/fever in the 12 months prior to the interviews appeared unrelated either to the level of daily hygiene, which was generally poor, or to the frequency of bathing. Many (65%) of the subjects paid no attention to limb care when bathing, and 44% did not use footwear. Over 80% made no effort to keep their afflicted limbs elevated, and 95% did not exercise. Most of the female interviewees felt shameful of their condition and were, in consequence, less likely to attend government clinics, for treatment, than the male interviewees. The drug treatment that the interviewees had received was often inadequate, and most had stopped seeking treatment because they had not perceived any significant treatment-attributable improvement in their condition. Modern lymphoedema-management strategies (based on regular washing, careful drying, and treatment, with antifungal, antibiotic or emollient creams, of the affected limbs, limb elevation, exercise, and use of footwear) had not reached the study communities and the local physicians were not aware of them. When dermatology life-quality indexes (DLQI) were calculated for the interviewees, the 26 most impaired subjects gave scores of 5-15 (mean=8.6). The DLQI for these subjects will be regularly re-evaluated, as a measure of the effectiveness of the CHBC programme that has now begun.

Knowledge on lymphatic filariasis and the response to July 2002 mass treatment campaign in two communities in the Galle district

OBJECTIVE

To ascertain the knowledge on filariasis and response to the July 2002 mass treatment campaign in two sample populations.

DESIGN

Application of pre-tested questionnaire by direct interviews of individuals from randomly selected streets.

METHODS

Study areas were a coastal community in Unawatuna (population sample 381), and an inland community in Baddegama (population sample 236) in the Galle district. They were interviewed twice, 4 weeks before the mass drug administration (MDA) and 4 to 7 days after.

RESULTS

The sample population of Unawatuna had a greater awareness of the clinical and parasitological features of the disease (p = 0.0003) and the drug treatment (p = 0.00380 than that of Baddegama. Only 5.5% of the combined sample attributed the cause of filariasis to a parasitic worm. However, over 70.0% of them knew that transmission was through mosquito bites. Volunteers formed 87.5% of the work force used for drug distribution in Unawatuna and 70.1% in Baddegama. The balance work force were Grama Niladaris and Public Health Midwives. Drugs were received by 76.9% of the Unawatuna sample compared with 89.0% at Baddegama (p < 0.001). Among those who received the drugs, consumption was 91.8% in Unawatuna and 96.2% in Baddegama. Taking the two communities together adverse effects were experienced by 22.9%. These effects in night time drug consumers (10.4%) were significantly less than in day time consumers (19.8%) (p < 0.005). The adverse effects were sleepiness (37.8%), malaise (28.2%), headache (16.8%), vomiting (5.1%), nausea (4.5%) and fever (3.9%). The message of mass treatment was carried to the community by the people themselves on the eve and on the day of drug distribution. Over 95% agreed that in future programs drugs should be delivered to their homes.