First Evidence for Two Independent and Different Leishmaniasis Transmission Foci in Sri Lanka: Recent Introduction or Long-Term Existence?

Cutaneous leishmaniasis caused by a genetic variant of L. donovani is being reported from Sri Lanka since year 2001. Patients presented from different geographical locations (600 patients from North or South and a minority of cases from other foci, 2001-2013) were studied. Analysis revealed two different sociodemographic and clinical profiles of leishmaniasis in Northern and Southern Sri Lanka. Also, the same different profiles were present in these foci since the onset of the recent outbreak and had independently propagated within each focus over the time. A profile of 14 parameters identified in the Northern focus was further examined with regard to other locations. Northwestern (10/14) and Central parts (9/14) of the island were more similar to Northern focus (14/14). Infection would have originated in one focus and spread to other 2 in Northern Sri Lanka. Southern focus was different from and appeared older than all others (2/14). Western focus that accommodates a large transient population had a mixed picture of North and South features (4/14). Lesions in North showed a slow progression and a nonulcerative nature (128/185, 69.2%), while those in South showed a rapid progression and less nonulcerative lesions (193/415, 46.5%). Clinical analysis favoured a parasite aetiology (considerable strain differences) rather than a host aetiology (age, gender, or genetics). Both foci demonstrated a biannual seasonal variation since the onset of the epidemic. Two peaks were observed during the early and latter parts of the year. Furthermore, long-term existence and recent spatiotemporal expansion and detection of leishmaniasis in this country rather than a recent introduction and establishment were indicated by these findings. Vigorous antimalarial activities that existed in Sri Lanka until few decades ago, lack of professional awareness, and more recent military activities that brought human population in close contact with a sylvatic cycle would have played a role in silent propagation of Leishmania parasites and subsequent increment in human cases, respectively, in this country.

Trends in Recently Emerged Leishmania donovani Induced Cutaneous Leishmaniasis, Sri Lanka, for the First 13 Years.

Sri Lanka reports a large epidemic of cutaneous leishmaniasis (CL) caused by an atypical L. donovani while regional leishmaniasis elimination drive aims at achieving its targets in 2020. Visceralization, mucotrophism, and CL associated poor treatment response were recently reported. Long-term clinico-epidemiological trends (2001-2013) in this focus were examined for the first time. Both constant and changing features were observed. Sociodemographic patient characteristics that differ significantly from those of country profile, microchanges within CL profile, spatial expansion, constant biannual seasonal variation, and nondependency of clinical profile on age or gender were evident. Classical CL remains the main clinical entity without clinical evidence for subsequent visceralization indicating presence of parasite strain variation. These observations make a scientific platform for disease control preferably timed based on seasonal variation and highlights the importance of periodic and continued surveillance of clinic-epidemiological and other characteristics.

Use of a clinical tool for screening and diagnosis of cutaneous leishmaniasis in Sri Lanka.

Cutaneous leishmaniasis (CL) was first detected in Sri Lanka in 1992.Local disease is caused by a genetically different variant of Leishmania donovani. Early case detection and management is the mainstay of L. donovani control. High degree of clinical suspicion is critical but a clinical diagnostic tool is not available for leishmaniasis. Current study described, for the first time, a two-staged clinical algorhythm that facilitates screening of CL in Sri Lanka by primary health care worker in stage 1 and management by medical professional in stage 2.Selected clinical markers of 400 patients suspected of CL were analysed retrospectively with laboratory confirmation of leishmaniasis. Ten clinical markers predicted CL with a over 90% accuracy. Subsets of markers showed high levels of sensitivities (60-97.2%) and/or significant association with positive laboratory results as compared to negative lesions [typical onset (acne-form, painless non-itchy), (P = 0.026), size up to 2 cm (P = 0.046), well-defined edges (P = 0.002), regular edges (P = 0.018), rounded shape (P = 0.030), and lesions at 5-8 months (P = 0.052)]. Five of them (typical onset, number up to 2, small size, rounded edges, and rounded shape) also had > 70% sensitivity levels as compared to laboratory findings. Typical onset had the highest sensitivity of 97% and a PPV of 72%. Lesions at 5-8 months duration having defined edges (P = 0.013, specificity 89.7%, PPV 83.1) or having regular edges (P = 0.006, specificity 86.2%, PPV 82.4%) were also predictive of CL. Most of early laboratory-confirmed ( < 12 months) lesions remained < 3 cm (sensitivity > 67%, PPV > 70%) and had defined edges (sensitivity of 52-71%, specificity 46.7-68.8%), (PPV 75.1-86%). Four clinical markers served as good diagnostic markers in both early ( ≤ 4) and late (>12 months) lesions, viz. typical onset (91.3-98.4%), presence of ≤ 2 lesions (sensitivity 82.6-94.7%), size ≤ 2 cm (66.9-73.7%), and regular edges (68.6-76.3%). Reliability of clinical markers generally declined in chronic lesions. However, small lesions of over 12 months were highly indicative of CL (sensitivity of 66%, specificity 66.7%). None of the single/combination markers, however, were 100% sensitive or specific, highlighting the undeniable usefulness of laboratory confirmation, in diagnosis. Decision-making algorithm used 10 basic clinical features for screening and seven specific clinical markers for clinical handling and referral for investigations.

Folliculitis decalvans--a retrospective study in a tertiary referred centre, over five years.

Folliculitis decalvans is a rare condition affecting mainly the scalp leading to scarring alopecia. Aetiology of the condition is still unknown, abnormal host response to Staphylococcus aureus has been postulated. We present a retrospective analysis of six cases of folliculitis decalvans presented to National Skin Centre (NSC), Singapore for the past five years, 1995-2000. The mean age of presentation was 39 years and ages ranged from 17 to 62 years. There were five male patients and one female patient. Duration of symptoms at presentation varied from six months to seven years. Occipital and vertex areas of the scalp were the only regions involved. Staphylococcus aureus was isolated in three patients; in one patient culture yielded negative results and no culture was done in the other two patients. All our patients were treated with several separate courses of systemic antibiotics which include doxycycline, erythromycin, minocycline, co-trimoxazole, cloxacillin, erythromycin, rifampicin and clindamycin. In addition one patient was treated with fucidic acid and zinc sulphate. The disease ran a protracted course with temporary improvement while on antibiotic and flare up of disease when antibiotics were stopped. The effectiveness of early treatment with rifampicin has been highlighted in some case reports in the past. We did use rifampicin in one of our patients. Our concern over emergence of antibiotic resistance, if used widely, may not permit us to use rifampicin on a wide scale.