Risk factors for anthroponotic cutaneous leishmaniasis in unresponsive and responsive patients in a major focus, southeast of Iran

Abstract

Cutaneous leishmaniasis (CL) is a serious health challenge at the global level due to Leishmania tropica. This study was conducted to evaluate the risk factors associated with anthroponotic CL (ACL) in unresponsive (patient who does not heal and remains with an active lesion, despite receiving two courses of intra-lesional Glucantime along with cryotherapy and one cycle of systemic Glucantime) and responsive patients in a major focus in southeastern Iran. A case-control study was conducted from April 2015 to October 2016 in the southeast of Iran. Patients were recruited in a major ACL focus from unresponsive and responsive cases. These patients were compared for environmental, clinical, and demographic characteristic factors. Twenty-five risk related factors were analyzed using multivariate logistic regression and backward elimination stepwise models. P<0.05 was defined to be statistically significant. In general, 340 patients with ACL comprising 72 (21.2%) unresponsive cases and 268 (78.8%) responsive cases with active lesions or scars were analyzed by estimating odds ratio (OR). All isolates from 15 responsive and 15 unresponsive patients were characterized as Leishmania tropica based on the BLAST and phylogenic analyses by PCR sequences of the Hsp70 and ITS1 loci. Among the 25 variables, 4 major risk factors including poor interior housing conditions (OR = 1.99, confidence interval (CI) = 1–3.93, P<0.04), history of chronic diseases (OR = 6.22, CI = 2.51–15.44, P≤0.001), duration of lesion in the patients referred ≥13 months (OR = 74.99, CI = 17.24–326.17, P≤0.001), and 5–12 months (OR = 7.42, CI = 3.07–17.92, P≤0.001) than lesions with ≤4 months of age and age groups ≥51 years (OR = 3.85, CI = 1.04–14.22, P<0.04) than those ≤7 years, were significantly associated with unresponsive forms. Improving interior house construction protecting high risk individuals and those with debilitating diseases from being bitten by sand flies, together with the early detection and effective treatment of older age groups with history of chronic diseases are highly important measures for preventing unresponsive forms in patients with ACL in southeastern Iran.

Expansion of urban cutaneous leishmaniasis into rural areas of southeastern Iran: Clinical, epidemiological and phylogenetic profiles explored using 7SL high resolution melting‐PCR analysis

“…Numerous risk determinants have contributed to the recent rise in transmission, the incidence of cases and expansion to new geographical ranges. These include environmental changes, anthropogenic modifications, population displacement, climate change, global conflict, poor standards of living and drug resistance (Aflatoonian et al, ; Bamorovat, Sharifi, Aflatoonian, et al, ; Bamorovat et al, ; Desjeux, ; Nikonahad et al, ; Oliaee et al, ). In the presence of such pre‐existing risk factors, CL has become a dynamic disease, as has been documented by several reports (Bailey et al, ; Karimkhani et al, ; WHO, ).…”

Emerging Epidemics of Cutaneous Leishmaniasis in Iran: Operational Aspects, Management and Implemented Control Approaches

“…Over the past decades, global data indicated emergence of new CL foci in different countries, i.e., Bolivia [6], Pakistan [7], Afghanistan [8], Morocco [9], Israel [10], Brazil [11], Libya [12], Sri Lanka [13], Europe [14] and Iran [15]. Various risk factors including environmental modifications due to urbanization and natural disasters, lack of competent vector and reservoir control strategies, population displacements, drug resistance, poor sanitation, and human behaviors play essential roles in expansion of the disease [1,5,[16][17][18][19]. The mentioned risk factors can converge to gradual or sudden emergence of epidemics and longlasting endemic foci can also erupt into epidemics [11].…”

“…The standard therapy for all clinical forms of leishmaniasis is pentavalent antimonial drugs, including meglumine antimoniate (Glucantime) and sodium stibogluconate (Pentostam), although the latter drug has currently no further use in the treatment of leishmaniasis [52]. Most of the clinical features are unresponsive to therapy and serve as the primary source for the transmission of the Leishmania agent [19,48,[53][54][55].…”

“…The results also suggested that shrinkage in the human reservoir pool in response to the intervention might play a significant role in prolonging the preventive effect beyond the insecticidal life of impregnated materials in foci of ACL. Special attention should be paid to those with underlying diseases including diabetics, young children, opium addicted individuals, HIV coinfection and those with chronic diseases [19,[87][88][89] who might be at higher risk of contracting severe infection, particularly during the transmission season.…”

“…papatasi as the primary biological vector. In the foci where R. opimus is the primary host, the inexpensive and remarkably effective approach [19,76,77] was using zinc phosphide [2.5%) as a rodenticide. Rhombomys is readily identifiable by its burrow system and distinctive morphology [61,75].…”