A case of a pulmonary-renal syndrome caused by streptococcal infection.

Pulmonary-renal syndrome (PRS) is defined as a combination of diffuse alveolar haemorrhage and glomerulonephritis. An 18-year-old woman visited our hospital with a 2-day history of fever, dyspnoea, and leg edema. Laboratory investigations revealed an elevated inflammatory reaction, increased serum creatinine levels, and normocytic anaemia. Additionally, the anti-streptolysin-O titre was positive, and complement component-3 levels were decreased. Urinalysis revealed proteinuria and hematuria. Bronchoalveolar lavage aliquots were progressively more hemorrhagic. These findings supported a diagnosis of PRS secondary to streptococcal infection. The patient was treated with high-dose methylprednisolone and antibiotics. After 4 days of treatment, her respiratory symptoms and serum creatinine levels improved. Steroid tapering was performed over 15 days. The findings in this case indicate that streptococcal infection is a potential cause of PRS, and that short-term steroid therapy is an effective treatment.

Association of Plasma Branched-Chain and Aromatic Amino Acids with Reduction in Kidney Function Evaluated in Apparently Healthy Adults.

The published literature on the association of circulatory branched-chain amino acids (BCAAs) and aromatic amino acids (AAAs) with reduced kidney function is inconsistent or conflicting. Clarification of it might help to better understand the underlying pathophysiology and to determine potential biomarkers for early detection and evaluation of kidney function decline. Our main purpose was to explore and clarify the potential relationships of individual BCAAs and AAAs with estimated glomerular filtration rate (eGFR) decline. We included the data from 2804 healthy subjects and categorized them into three groups based on eGFR tertiles. The associations between individual amino acids and eGFR were explored by covariate-adjusted logistic regression models. There was a progressive increase in the concentrations of BCAAs and AAAs from the upper to the lower tertiles. We revealed significant positive associations of isoleucine, leucine, and phenylalanine with lower tertiles of eGFR in the adjusted models (p < 0.01-0.001). The findings hold a promising potential of using plasma isoleucine, leucine, and phenylalanine levels for evaluation of kidney function decline. Future longitudinal studies should investigate the causal association between altered levels of these amino acids and impaired kidney function and also the utility of the former as potential biomarkers for evaluating the risk and early detection of the latter.

Plasma Branched-Chain and Aromatic Amino Acids in Relation to Hypertension.

Findings of the available studies regarding the roles of branched-chain amino acids (BCAAs) and aromatic amino acids (AAAs) in hypertension are inconsistent, conflicting and inconclusive. The purpose of this study was to explore and clarify the existence of any relationships of individual BCAAs and AAAs with hypertension with adjustments for potential relevant confounders. A total of 2805 healthy controls and 2736 hypertensive patients were included in the current analysis. The associations between individual amino acids and hypertension were explored by logistic regression analyses adjusted for potential confounding variables. Among the investigated amino acids, only the BCAAs showed consistently significant positive associations with hypertension in the adjusted models (p-trend < 0.05 to 0.001). However, compared with the corresponding lowest quartile of individual BCAAs, the positive association with hypertension remained significant only in the highest quartile (p < 0.01 to 0.001). We confirmed in a relatively large cohort of subjects that BCAAs, not AAAs, demonstrated consistent positive associations with hypertension. The results display the promising potential for the use of BCAAs as relevant and accessible biomarkers, and provide perspectives on interventions directed towards the reduction in plasma BCAA levels in the prevention and management of hypertension.