Challenges for management of post kala-azar dermal leishmaniasis and future directions

Differences in the Cellular Immune Response during and after Treatment of Sudanese Patients with Post-kala-azar Dermal Leishmaniasis, and Possible Implications for Outcome

BACKGROUND

The host cellular immune response associated with two treatments for post-kala-azar dermal leishmaniasis (PKDL) - paromomycin plus miltefosine (Arm 1), and liposomal amphotericin B plus miltefosine (Arm 2) - was examined in Sudanese patients before treatment (D0), at the end of treatment (D42), and during the post-treatment period (D180).

METHODS

Whole blood samples were stimulated with soluble Leishmania antigen for 24 h (whole blood assay [WBA]) and the concentrations of Th1/Th2/Th17-associated cytokines, IP-10, PDL-1 and granzyme B were determined.

RESULTS

The Arm 1 treatment (98.2% cure rate) induced a Th1/Th2/Th17 response, while the Arm 2 treatment (80% cure rate) induced a Th1/Th2 response. Five Arm 2 patients relapsed and showed lower IFN-γ, TNF and IL-1β concentrations at D0 than non-relapsers in this Arm. In patients with low-IFN-γ-production at D0, Arm 1 treatment led to a better host immune response and clinical outcome than Arm 2 treatment.

CONCLUSIONS

A Th1/Th2/Th17 response was associated with a higher cure rate. Patients with low IFN-γ, TNF and IL-1β before treatment are more likely to relapse if they undergo Arm 2-type treatment. Determining IFN-γ, TNF and IL-10 levels prior to treatment could help predict patients at higher risk of relapse/recovery from PKDL.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03399955, Registered 17 January 2018, https://clinicaltrials.gov/study/ NCT03399955.

The usefulness of trained field workers in diagnosis of post-kala-azar dermal leishmaniasis (PKDL) and clinico-epidemiological profile in highly endemic areas of Bihar

BACKGROUND

Surveillance of post-kala-azar dermal leishmaniasis (PKDL) is critical to the elimination of visceral leishmaniasis (VL). In this study we assessed the feasibility of using trained field workers for detecting suspected PKDL cases.

METHODS

A cross-sectional study using a multistage sampling technique was conducted in the Araria district of Bihar. Trained field workers were utilized for identification of suspected PKDL case.

RESULTS

We investigated 57 099 individuals from 11 300 households. The trained field workers were useful in identifying 107 (18%) probable PKDL cases. The calculated PKDL prevalences were 18.7/10 000 and 9.7/10 000 for probable and confirmed PKDL cases, respectively. The median duration of onset of PKDL was 23 months (interquartile range 16.5-56.5). The younger age group developed PKDL significantly more often compared with the older age group (p=0.007). Of the 107 patients, 25 (55.5%) were positive by microscopy of slit skin smear and 42 (93.3%) by polymerase chain reaction. Of 45 patients, 33 (73%) PKDL cases were cured after full treatment. The risk of not being cured with incomplete treatment was three times higher than with complete treatment (relative risk 3.12 [95% confidence interval 1.23 to 8.67], p=0.004).

CONCLUSIONS

We conclude that the prevalence of PKDL is high and the use of trained field workers may be feasible to actively detect PKDL cases in VL-endemic areas of Bihar, India.

Case Report: Treatment of Widespread Nodular Post kala-Azar Dermal Leishmaniasis with Extended-Dose Liposomal Amphotericin B in Bangladesh: A Series of Four Cases

Post kala-azar dermal leishmaniasis (PKDL) is a skin manifestation which usually appears after visceral leishmaniasis. It is now proved that PKDL patients serve as a reservoir for anthropometric leishmanial transmission. Hence, to achieve the kala-azar elimination target set by the World Health Organization in the Indian Subcontinent, PKDL cases should be given priority. The goal of treatment for PKDL should be early reepithelizlization and rapid cure, but unfortunately this has been difficult to achieve, especially for patients with severe lesions. Therefore, we describe here four cases of PKDL who had widespread nodular and macular lesions and were treated with two cycles of LAmB doses with 20 mg/kg body weight divided into four equal doses (each dose contains 5 mg/kg) administered every alternate day. This treatment schedule achieved 100% treatment success with the minimal safety concern.

Study on the safety and efficacy of miltefosine for the treatment of children and adolescents with post-kala-azar dermal leishmaniasis in Bangladesh, and an association of serum vitamin E and exposure to arsenic with post-kala-azar dermal leishmaniasis: an open clinical trial and case-control study protocol

INTRODUCTION

Post-kala-azar dermal leishmaniasis (PKDL) is a dermatological complication that occurs primarily among treated visceral leishmaniasis (VL) patients, and sporadically in a few without a history of VL. It mostly affects children and adolescents but is also common in adults. The conventional treatment with 120 intramuscular injections of sodium stibogluconate (SSG) is phasing out. Miltefosine (MF) is the only eventual alternative to SSG; however, its efficacy and safety profiles for treatment of children and adolescents with PKDL are lacking. In addition, risk factors for PKDL are poorly investigated. Host genetic, nutritional and environmental factors could be potential risk factors. As such, here we propose to evaluate the efficacy and safety of MF for 12 weeks at an allometric dose for children and adolescents with PKDL, and also to explore potential risk factors for PKDL.

METHODS AND ANALYSIS

A cross-sectional survey will look for suspected participants with PKDL among treated VL children and adolescents, a subsequent open clinical trial with MF at allometric dose, with a follow-up at 12 months. A case-control study will be carried out for PKDL risk factors. Assuming 95% cure rate, 95% CI and α=0.05, a sample size of 73 children with PKDL is needed. Considering an attrition rate of 10%, the final sample size is 80 children in each group. Descriptive and analytical analyses will be performed. Primary outcome is safety and cure rate of 12 weeks of treatment with MF.

ETHICS AND DISSEMINATION

International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B) Ethical Review Committee (ERC) approved the protocol (PR#013045). Written informed consent will be taken from all participants and their guardians (in case of minor). A Data and Safety Monitoring Board (DSMB) of ICDDR,B ERC will monitor all study activities to ensure the safety of the participants.

TRIAL REGISTRATION NUMBER

NCT02193022; Pre-results.

Uniting mathematics and biology for control of visceral leishmaniasis

The neglected tropical disease (NTD) visceral leishmaniasis (VL) has been targeted by the WHO for elimination as a public health problem on the Indian subcontinent by 2017 or earlier. To date there is a surprising scarcity of mathematical models capable of capturing VL disease dynamics, which are widely considered central to planning and assessing the efficacy of interventions. The few models that have been developed are examined, highlighting the necessity for better data to parameterise and fit these and future models. In particular, the characterisation and infectiousness of the different disease stages will be crucial to elimination. Modelling can then assist in establishing whether, when, and how the WHO VL elimination targets can be met.