Pharmacy Practice Department, College of Pharmacy, Shaqra University, Shaqra 11961, Saudi Arabia; Clinical Pharmacy Department, National Cancer Institute, Cairo University, Fom El Khalig Square, Kasr Al-Aini Street, Cairo 11796, Egypt.
Department of Otolaryngology, Faculty of Medicine, Al-Azhar University, 34518 Damietta, Egypt.
Am J Otolaryngol. 2023 Jul-Aug;44(4):103871. doi: 10.1016/j.amjoto.2023.103871. Epub 2023 Mar 30.
COVID-19 has been frequently demonstrated to be associated with anosmia. Calcium cations are a mainstay in the transmission of odor. One of their documented effects is feedback inhibition. Thus, it has been advocated that reducing the free intranasal calcium cations using topical chelators such as pentasodium diethylenetriamine pentaacetate (DTPA) could lead to restoration of the olfactory function in patients with post-COVID-19 anosmia.
This is a randomized controlled trial that investigated the effect of DTPA on post-COVID-19 anosmia. A total of 66 adult patients who had confirmed COVID-19 with associated anosmia that continued beyond three months of being negative for SARS-CoV-2 infection. The included patients were randomly allocated to the control group that received 0.9 % sodium chloride-containing nasal spray or the interventional group that received 2 % DTPA-containing nasal spray at a 1:1 ratio. Before treatment and 30 days post-treatment, the patients' olfactory function was evaluated using Sniffin' Sticks, and quantitative estimation of the calcium cations in the nasal mucus was done using a carbon paste ion-selective electrode test.
Patients in the DTPA-treated group significantly improved compared to the control group in recovery from functional anosmia to hyposmia. Additionally, they showed a significant post-treatment reduction in the calcium concentration compared to the control group.
This study confirmed the efficacy of DTPA in treating post-COVID-19 anosmia.
COVID-19 经常与嗅觉丧失有关。钙离子是气味传递的主要物质之一。其已被证实的作用之一是反馈抑制。因此，有人主张使用局部螯合剂（如五钠二乙撑三胺五乙酸（DTPA））减少鼻腔内游离钙离子，可以恢复 COVID-19 后嗅觉丧失患者的嗅觉功能。
这是一项随机对照试验，旨在研究 DTPA 对 COVID-19 后嗅觉丧失的影响。共有 66 名成年患者确诊 COVID-19 后伴有嗅觉丧失，且在 SARS-CoV-2 感染检测阴性后持续超过三个月。纳入的患者被随机分配到对照组（接受 0.9%含氯化钠的鼻腔喷雾剂）或干预组（接受 2%含 DTPA 的鼻腔喷雾剂，比例为 1:1）。在治疗前和治疗后 30 天，使用嗅觉测试棒评估患者的嗅觉功能，并使用碳糊离子选择性电极测试定量估计鼻腔粘液中的钙离子。
与对照组相比，DTPA 治疗组的患者在从功能性嗅觉丧失恢复到嗅觉减退方面有显著改善。此外，与对照组相比，DTPA 治疗组患者在治疗后钙离子浓度显著降低。
这项研究证实了 DTPA 治疗 COVID-19 后嗅觉丧失的疗效。
