The purpose of our cohort study was to quantify olfactory deficits in Coronavirus disease 2019 (COVID-19) patients using Sniffin' Sticks and a pre-post design to evaluate olfactory recovery. Thirty adult patients with laboratory-confirmed mild to moderate forms of COVID-19 underwent a quantitative olfactory test performed with the Sniffin' Sticks test (SST; Burghardt, Wedel, Germany), considering olfactory threshold (T), odor discrimination (D), and odor identification (I). Results were presented as a composite TDI score (range 1-48) that used to define functional anosmia (TDI ≤ 16.5), hyposmia (16.5 < TDI < 30.5), or functionally normal ability to smell (TDI ≥ 30.5). Patients also self-evaluated their olfactory function by rating their ability to smell on a visual analogue scale (Visual Analog Scale rating) and answering a validated Italian questionnaire (Hyposmia Rating Scale). Patients were tested during hospitalization and about 2 months after symptoms onset. During the hospitalization, the overall TDI score indicated that our cohort had impairments in their olfactory ability (10% was diagnosed with anosmia and more than 50% were hyposmic). Almost all patients showed a significant improvement at around 1 month following the first test and for all the parts of the SST except for odor identification. None of the subjects at 1 month was still diagnosed with anosmia. We also quantified the improvement in the TDI score based on initial diagnosis. Anosmic subjects showed a greater improvement than hyposmic and normosmic subjects. In conclusion, within a month time window and 2 months after symptoms' onset, in our cohort of patients we observed a substantial improvement in the olfactory abilities.

中文翻译：

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找回失去的东西：在 COVID-19 后恢复轻度至中度患者的嗅觉。

我们的队列研究的目的是使用 Sniffin' Sticks 和前后设计来量化 2019 年冠状病毒病 (COVID-19) 患者的嗅觉缺陷，以评估嗅觉恢复情况。30 名实验室确诊的轻度至中度 COVID-19 成年患者接受了 Sniffin' Sticks 测试（SST；Burghardt，Wedel，德国）的定量嗅觉测试，考虑嗅觉阈值 (T)、气味辨别 (D)、和气味鉴别（一）。结果以综合 TDI 评分（范围 1-48）的形式呈现，用于定义功能性嗅觉丧失（TDI ≤ 16.5）、嗅觉减退（16.5 < TDI < 30.5）或功能性正常嗅觉能力（TDI ≥ 30.5）。患者还通过视觉模拟量表（视觉模拟量表评级）评估他们的嗅觉能力并回答经过验证的意大利问卷（低尿症评级量表）来自我评估他们的嗅觉功能。患者在住院期间和症状出现后约 2 个月接受了检测。住院期间，总体 TDI 评分表明我们的队列有嗅觉能力受损（10% 被诊断为嗅觉丧失症，超过 50% 为嗅觉减退）。几乎所有患者在第一次测试后约 1 个月时，除气味识别外，SST 的所有部分均表现出显着改善。1 个月时，没有受试者仍被诊断患有嗅觉丧失症。我们还根据初步诊断量化了 TDI 评分的改善。嗅觉丧失的受试者比嗅觉低下和嗅觉正常的受试者表现出更大的改善。总之，在一个月的时间窗口内和症状出现后两个月内，我们观察到患者的嗅觉能力有了显着改善。