RESUMO
Invasive aspergillosis (IA) represents a common form of fungal infection caused by various species of Aspergillus that most frequently affect immunocompromised patients. Typically, this disease occurs preferentially in high-risk groups including patients infected with the human immunodeficiency virus (HIV), patients with leukemia, patients with autoimmune diseases, and organ transplant patients undergoing medical immunosuppression. Considered the second most common cause of opportunistic fungal infection in humans after Candida albicans, this pathogen predominantly affects the lungs, but it may also spread by a hematogenous route to various organs and have a heterogeneous presentation. Owing to its high iodine levels, high perfusion, and enclosed capsule, the thyroid gland is considered to have a lower susceptibility to microbial invasion, and it is fairly uncommon to find associated infectious nodules. In metabolic imaging, 18F-FDG-PET/CT has become increasingly useful for detecting a wide range of infectious and inflammatory diseases and is already the gold standard for certain indications. According to the literature, no studies of hypermetabolic nodular thyroid aspergillosis on 18F-FDG-PET/CT confirmed on histology have yet been reported. Here, we report the first case of a patient with a heterogeneous presentation of IA and the presence of a hypermetabolic nodule in the thyroid with a surprising result.
RESUMO
BACKGROUND: High ratio of the carbon dioxide veno-arterial difference to the oxygen arterial-venous difference (PvaCO2/CavO2) is associated with fluid bolus (FB) induced increase in oxygen consumption (VO2). This study investigated whether PvaCO2/CavO2 was associated with decreases in blood-lactate levels FB in critically ill patients with hyperlactatemia. METHODS: This prospective observational study examined adult patients in the intensive care unit (ICU) with lactate levels > 1.5 mmol/L who received FBs. Blood-lactate levels were measured before and after FB under unchanged metabolic, respiratory, and hemodynamic conditions. The primary outcome was blood-lactate levels after FB. Significant decreases in blood-lactate levels were considered as blood-lactate levels < 1.5 mmol/L or a decrease of more than 10% compared to baseline. RESULTS: The study enrolled 40 critically ill patients, and their median concentration of blood lactate was 2.6 [IQR:1.9 - 3.8] mmol/L. There were 27 (68%) patients with PvaCO2/CavO2 ≥ 1.4 mmHg/ml, and 10 of them had an increase in oxygen consumption (dVO2) ≥ 15% after FB, while 13 (32%) patients had PvaCO2/CavO2 < 1.4 mmHg/ml before FB, and none of them had dVO2 ≥ 15% after FB. FB increased the cardiac index in patients with high and low preinfusion PvaCO2/CavO2 (13.4% [IQR: 8.3 - 20.2] vs. 8.8% [IQR: 2.9 - 17.4], p = 0.34). Baseline PvaCO2/CavO2 was not found to be associated with a decrease in blood lactate after FB (OR: 0.88 [95% CI: 0.39 - 1.98], p = 0.76). A positive correlation was observed between changes in blood lactate and baseline PvaCO2/CavO2 (r = 0.35, p = 0.02). CONCLUSIONS: In critically ill patients with hyperlactatemia, PvaCO2/CavO2 before FB cannot be used to predict decreases in blood-lactate levels after FB. Increased PvaCO2/CavO2 is associated with less decrease in blood-lactate levels.