Quantification of Metal(loid)s in Lubricating Eye Drops Used in the Treatment of Dry Eye Disease.

The aim of the study was to evaluate the presence of metal(loid)s in lubricating eye drops used in the treatment of dry eye disease. The concentrations of Al, As, Ba, Cd, Co, Cu, Cr, Pb, Fe, Mg, Mn, Mo, Ni, Se, V, and Zn were determined in 19 eye drop samples using inductively coupled plasma optical emission spectrometry (ICP OES). The limit of detection (LOD) and limit of quantification (LOQ) values for the quantified elements ranged from 0.0002-0.0363 (mg/L) and 0.0007-0.1211 (mg/L), respectively. High values of concentrations of Al (2.382 µg/g), As (0.204 µg/g), Ba (0.056 µg/g), Cd (0.051 µg/g), Co (1.085 µg/g), Cr (0.020 µg/g), Cu (0.023 µg/g), Fe (0.453 µg/g), Mg (24.284 µg/g), Mn (0.014 µg/g), Mo (0.046 µg/g), Ni (0.071 µg/g), Pb (0.049 µg/g), Se (0.365 µg/g), V (0.083 µg/g), and Zn (0.552 µg/g) were quantified in samples of eye drops with and without preservatives. The concentrations of As (5 samples) and Cd (3 samples) were higher than those allowed by the Brazilian Pharmacopoeia for impurities (parenteral use). The value of Co content (µg/g) in a sample was higher than the value established by the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH Q3D (R2)) in the parenteral route. The daily eye drop instillation exposure (µg/day) was below the values from the parenteral-permitted daily exposure (PDE) set by the ICH Q3D guideline (R2). The presence of heavy metals in eye drops is an alert to regulatory agencies in several countries so that control and inspections can be carried out.

Iron metabolism disorders of patients with chronic paracoccidioidomycosis.

Paracoccidioidomycosis (PCM) is caused by Paracoccidioides spp.; during infection, some host mechanisms limit the availability of iron, thereby reducing its reproduction. However, Paracoccidioides spp. can evade the immune defense and, even under limited iron conditions, use this mineral for growth and dissemination. This study evaluated the iron metabolism of 39 patients who were diagnosed with chronic PCM from 2013 to 2021. The forms of iron before treatment and at the time of clinical cure were evaluated based on the following: serum ferritin levels (storage iron); total iron-binding capacity (TIBC) and transferrin saturation (TSAT) level (transport iron); red blood cell (RBC), hemoglobin (Hb), hematocrit (HCT), and soluble transferrin receptor (sTfR) levels; and sTfR/log ferritin ratio (functional iron). The mean age of the patients was 54.5 years (±6.7 years). Most patients were men (97.4%), rural workers (92.1%), and smokers (84.6%); furthermore, most had moderate disease severity (66.7%). After achieving clinical cure, we observed that serum ferritin levels decreased, and parameters of functional iron increased. The extent of alteration in these parameters were more pronounced in severe cases than in to mild or moderate cases. Furthermore, moderate correlations were observed between C-reactive protein and the Hb (r = -0.500; p = 0.002), RBC (r = -0.461; p = 0.005), HCT (r = -0.514; p = 0.001), and iron levels (r = -0.491; p = 0.002). However, it is possible to infer that PCM interferes with functional and storage iron because improvements in these parameters after treatment as well as associations with disease severity were observed. PCM can lead to anemia of inflammation, which can be differentiated from iron deficiency anemia by a careful investigation of the iron form parameters.