Shah Divya, Cojuc-Konigsberg Gabriel, Brown Stacy D, Chiarella Sergio E, Volcheck Gerald W, Kita Hirohito, Garvey Lene H, Gonzalez-Estrada Alexei
Department of Internal Medicine, University of Arizona College of Medicine, Phoenix, Ariz.
Medical School, Faculty of Health Sciences, Universidad Anahuac, Mexico City, Mexico.
J Allergy Clin Immunol Glob. 2024 Nov 26;4(1):100372. doi: 10.1016/j.jacig.2024.100372. eCollection 2025 Feb.
Chlorhexidine gluconate (CHX), a common cause of perioperative anaphylaxis, is frequently used for skin testing in allergy evaluations. Although CHX's maximal nonirritating concentrations are known, the stability of its dilutions for skin testing remains unexplored, particularly when sterile water for injection (SWFI) or normal saline (NS) are used as diluents.
Our aim was to evaluate the stability and precipitation of CHX when diluted with SWFI or NS for drug allergy skin testing.
CHX dilutions (5-0.002 mg/mL) were prepared using SWFI and NS. HPLC and UV-visible spectrophotometry were used to assess stability and precipitation over 48 hours. Turbidity was measured at various time points to monitor precipitation.
HPLC analysis showed no significant differences in peak heights between CHX-SWFI and CHX-NS dilutions. However, visible precipitation and increased turbidity (>100 NTU) were observed in CHX-NS at higher concentrations (5 mg/mL) after 60 minutes. No precipitation occurred in CHX-SWFI at any concentration for 48 hours.
For CHX skin testing, SWFI is the preferred diluent at concentrations higher than 0.02 mg/mL to avoid precipitation. Using NS for the final dilution from 0.02 to 0.002 mg/mL is feasible and reduces injection pain. Except for CHX-NS at 5 mg/mL, reagents can be prepared up to 24 hours before testing.
葡萄糖酸氯己定（CHX）是围手术期过敏反应的常见诱因，在过敏评估中常用于皮肤试验。尽管已知CHX的最大无刺激浓度，但其用于皮肤试验的稀释液稳定性仍未得到探索，尤其是当使用注射用水（SWFI）或生理盐水（NS）作为稀释剂时。
我们的目的是评估用SWFI或NS稀释用于药物过敏皮肤试验的CHX时的稳定性和沉淀情况。
使用SWFI和NS制备CHX稀释液（5 - 0.002 mg/mL）。采用高效液相色谱法（HPLC）和紫外可见分光光度法评估48小时内的稳定性和沉淀情况。在不同时间点测量浊度以监测沉淀。
HPLC分析显示CHX - SWFI和CHX - NS稀释液的峰高无显著差异。然而，60分钟后，较高浓度（5 mg/mL）的CHX - NS中观察到明显沉淀和浊度增加（>100 NTU）。48小时内，任何浓度的CHX - SWFI均未出现沉淀。
对于CHX皮肤试验，浓度高于0.02 mg/mL时，SWFI是首选稀释剂，可避免沉淀。使用NS将最终浓度从0.02 mg/mL稀释至0.002 mg/mL是可行的，且可减轻注射疼痛。除5 mg/mL的CHX - NS外，试剂可在试验前24小时内配制。
