ABSTRACT
BACKGROUND: Nocturnal hypoxemia adversely affects outcomes in patients with cystic fibrosis (CF). Although an early detection of this abnormality may be desirable, still its predictability remains uncertain. The Lung Clearance Index (LCI) is a measure of lung ventilation distribution obtained from a multiple-breath washout technique (MBW), recently implemented in patients with CF. This study aimed to establish whether the LCI predicts nocturnal hypoxemia in patients with stable CF, with mild to moderate disease, and normal diurnal gas exchange. METHODS: 31 stable patients (15 males, mean age 17.4 ± 5.2 years) with mild to moderate CF, normoxic when awake, were enrolled. In all patients we performed nocturnal cardio-respiratory polygraphy, lung function measurement, and MBW test to derive LCI values. RESULTS: LCI was abnormal in most of the patients and inversely correlated with mean nocturnal SpO2 (r = -0.880 p < 0.01). A receiver operating characteristic (ROC) analysis, performed to assess whether LCI predicted nocturnal hypoxemia, revealed a high predictive accuracy of LCI for nocturnal desaturation (AUC = 0.96; Youden index = 0.79). Forced expiratory volume in 1 s (FEV1) was predictive only in patients with more severe airway obstruction, with a moderate degree of accuracy (AUC 0.71). CONCLUSIONS: The LCI showed a high effectiveness in predicting nocturnal hypoxemia in stable patients with CF, particularly when compared with a traditional parameter of lung function such as FEV1.
Subject(s)
Cystic Fibrosis/complications , Hypoxia/diagnosis , Hypoxia/etiology , Lung/metabolism , Pulmonary Ventilation , Respiratory Function Tests/methods , Adolescent , Child , Cystic Fibrosis/physiopathology , Female , Forced Expiratory Volume , Humans , Male , Polysomnography , Predictive Value of Tests , Respiratory Function Tests/trends , Severity of Illness Index , Young AdultABSTRACT
BACKGROUND: Many reports have confirmed that hypertriglyceridemia (HTG) is more common in HIV-infected patients than in the general population, but the relationship between HTG and clinical conditions have not been well established. This work analyzes the relationships between CD4+ cell count, HTG and the presence of active intercurrent infections in patients hospitalized for HIV infection. METHODS: Blood specimens from hospitalized HIV-infected patients and healthy controls without HIV infection were analyzed. Clinical conditions when the specimens were collected were recorded. RESULTS: The average level of serum triglycerides from 89 HIV-infected patients was significantly higher than the 29 healthy controls (1.57 +/- 0.09 vs 0.78 +/- 0.08 mmol/l respectively) (p < 0.001). In the study group, HTG was detected in 25 patients (27%). Twenty-six patients had intercurrent infections and 50 were asymptomatic. Clinical conditions of the remaining 13 were not available. HTG was detected in 18 out of 26 patients having intercurrent infections (68%), and in 4 out of the 50 patients without active infections (8%) (p < 0.000000417). CONCLUSIONS: HTG was more frequent in HIV-infected patients than in healthy controls, and it was significantly associated with the presence of intercurrent infections. This has important diagnostic implications, because the presence of HTG might be considered an unspecific marker for intercurrent infections in HIV patients.
