No abstract

The various presentations of osseous Langerhans cell histiocytosis (LCH) make it difficult to distinguish from other bone diseases. In addition, there is no universally accepted protocol for managing osseous LCH for single non-central nervous system-risk lesions. Here, the rare cases of two paediatric patients, aged 1 and 2 years, who presented with a solitary tibial lesion at time of LCH diagnosis, are reported. One patient progressed to multiple lesions after curettage of the original lesion. Subsequently, both patients received preventive chemotherapy using the Taiwan Paediatric Oncology Group (TPOG) revised protocol for treating low risk patients with LCH, namely, TPOG LCH2002-LR. After receiving this treatment, which included a schedule of prednisolone and vincristine for 6 weeks, followed by prednisolone, vincristine and 6-mercaptopurine for a further 48 weeks, both patients are free from recurrence or progression.

This systematic review was performed to determine the population that benefited from prophylactic ivermectin. Seven databases of health-related studies were searched for eligible trials without language restrictions. Randomized controlled trials (RCTs) and cohort studies investigating ivermectin for coronavirus disease 2019 (COVID-19) prevention were included. Data were pooled using a random-effects model, and subgroups were analyzed by study type and the pre-or postexposure population. The certainty of the evidence was determined by the Grading of Recommendations Assessment, Development, and Evaluation approach. Furthermore, 4 RCTs and 4 cohort studies with a moderate to high risk of bias were included in the analysis. The prophylactic use of ivermectin significantly decreased the overall incidence of COVID-19 (odds ratio [OR], 0.26; 95% confidence interval [CI], 0.16-0.44). Nevertheless, the positive result was not supported by the RCT. Ivermectin was associated with a lower risk of COVID-19 (OR, 0.22; 95% CI, 0.12-0.40) in the preexposure population, whereas no protective effect was observed in the postexposure population (OR, 0.39; 95% CI, 0.09-1.67). In summary, prophylactic ivermectin did not prevent COVID-19 in the postexposure population. Although the protective effect of ivermectin was shown in the overall and preexposure populations, the results were unreliable owing to poor-quality evidence.