Biomedical subjects

Carmen Valbuena

Publications and source records attributed to Carmen Valbuena.

6 recordsLinked to original sources

PubMed2007

Systemic polyarteritis nodosa associated with acute Epstein-Barr virus infection.

Polyarteritis nodosa (PAN) is a rare cause of systemic vasculitis in children, affecting medium and small-sized arteries. We report on a patient who presented with prolonged fever, shock, acute renal failure with nephrotic range proteinuria, hypertension, and sudden deterioration of consciousness. Cranial tomography revealed a left extensive hemorrhagic lesion. Renal biopsy revealed a large fibrinoid necrosis lesion consistent with PAN. Epstein-Barr virus (EBV) infection was confirmed by real-time polymerase chain reaction (RT-PCR) detection of EBV DNA. The patient was successfully treated with oral prednisolone and intravenous pulse of cyclophosphamide. To our knowledge, this is the first reported case of c-PAN related to active EBV infection.

Acute Disease↗

PubMed2006

Antioxidant vitamins and risk of gastric cancer: a case-control study in Portugal.

We quantified the effect of antioxidant vitamins in gastric cancer risk, taking into account Helicobacter pylori seropositivity and overall fruit and vegetable intake. Incident cases were identified in two large hospitals in Porto, Portugal, and controls were randomly sampled among city dwellers. Food intake was assessed with a previously validated semiquantitative food-frequency questionnaire. A commercially available chromatographic immunoassay was used for the detection of immunoglobulin G antibodies. Complete questionnaire information and serum samples were available for 233 cases and 311 controls. Compared with subjects in the lowest tertile of dietary intake, the odds ratios (ORs) for those in the highest were 0.85 (95% confidence interval, CI = 0.45-1.60) for vitamin C, 1.04 (95% CI = 0.60-1.80) for vitamin E, and 1.33 (95% CI = 0.77-2.30) for provitamin A carotenoids after further adjusting for fruit and vegetable consumption. Fruit and vegetables remained an independent protective factor (OR = 0.45; 95% CI = 0.23-0.89) after further adjustment for the intake of antioxidant vitamins. H. pylori status had no significant interaction with dietary items. Factors other than H. pylori infection and intake of vitamin C and provitamin A carotenoids seem to account for the inverse association between fruit and vegetable consumption and gastric cancer.

Aged↗

PubMed2005

[Lung-kidney syndrome].

The lung-kidney syndrome is characterized by the coexistence of glomerulonephritis and pulmonary hemorrhage. However these manifestations can define different pathologies. The association of diffuse pulmonary hemorrhage, glomerulonephritis and circulating anti-glomerular basement membrane antibodies define Goodpasture syndrome. We report a case of Goodpasture syndrome with review of the literature.

Aged↗

PubMed2004

Renal dopamine and salt sensitivity of blood pressure in IgA nephropathy.

BACKGROUND: Patients with chronic glomerulonephritis exhibit salt-sensitive (SS) hypertension. In the early stage, however, the exact characteristics are still unclear. A decrease in renal dopamine production under basal conditions or after a sodium load has been reported in a subset of patients with SS primary hypertension. AIMS: The present study examined 17 untreated IgA-N patients with near-normal renal function, to determine whether salt sensitivity appears before hypertension and whether this sensitivity is related to renal dopamine production. METHODS: Daily urinary excretion of dopamine, the amine precursor--L-DOPA, and metabolites was monitored in conditions of basal sodium ingestion, followed by three consecutive 5-day periods of 100, 20 and 350 mmol/day sodium intake. The sodium sensitivity index (SSI) was evaluated in each patient. In addition, the patients were considered SS when showing an increase > or =5 mm Hg in 24-hour mean BP when they changed from a 20- to a 350-mmol/day sodium diet. RESULTS: Urinary dopamine output was lower in SS than in salt-resistant patients throughout the study (p < 0.001). This was accompanied by lower creatinine clearance values and higher urinary protein excretion in SS IgA-N patients. A strong negative relationship was observed in these 17 IgA-N patients between the SSI and the daily urinary excretion of dopamine in conditions of both 20 mmol/day sodium intake (r2 = 0.592; p = 0.0003) and 350 mmol/day sodium diet (r2 = 0.352; p = 0.01). However, urinary dopamine output varied appropriately throughout the study in SS patients, in agreement with changes in sodium intake. CONCLUSION: We conclude that in IgA-N patients, a rightward shift in the 'pressure natriuresis' can appear before hypertension and is related with a reduced renal production of dopamine. It is suggested that decreased renal dopamine synthesis in SS IgA-N patients results from acquired tubulointerstitial injury. In contrast to what has been found in SS primary hypertension, renal dopamine may behave appropriately in SS IgA-N patients, as a compensatory hormone.

Adult↗

PubMedDate not supplied

[Solitary fibrous tumor -- report of two cases].

Solitary Fibrous Tumor is a rare neoplasm derived from mesenchymal cell. To achieve a diagnosis and to differentiate from others neoplasm immunohistochemical analysis is needed. The majority of these tumours are benign, and complete surgical resection remains the mainstay of therapy for both the benign and malignant variants. However, there are cases of local and distant recurrences, so patients should have a close follow-up and it is far incorrect to look at this lesion as definitely benign. The authors review clinical presentation, radiological features, histological findings, and treatment options for this tumor and report two clinical cases discussing the differences between them.

Adult↗

PubMedDate not supplied

Renal diseases: a 27-year renal biopsy study.

BACKGROUND: Data from registries of renal biopsy (RB), currently an important source for diagnosing renal disease, are available for a number of countries, but different patterns seem to exist in different countries. METHODS: We reviewed the records of all patients who underwent an RB at our institution over a 27-year period (January 1, 1977, to December 31, 2003), in northern Portugal, a European region with a predominantly Caucasian population. We aimed at identifying patterns of glomerular disease frequency, as well as the corresponding changes over time. The patients were grouped for analysis in 9-year intervals: period A (1977 through 1985), period B (1986 through 1994) and period C (1995 through 2003). RESULTS: Nephrotic syndrome was the most common clinical presentation for RB (42.0%), followed by urinary abnormalities (28.5%), acute renal failure (9.7%), chronic renal failure (9.3%) and nephritic syndrome (9.3%). Primary glomerulonephritis (GN) was the most common type of kidney disease in the present study, representing 50.4% of all renal pathology, followed by secondary GN (29.4%) and vascular and tubulointerstitial diseases (14.0%). The relative frequency of secondary GN and vascular and tubulointerstitial diseases increased significantly over time, and so did IgA nephropathy, the most common type of primary glomerular disease in the present study (31.2%). Focal and segmental glomerulosclerosis represented 6.9% of primary glomerular disease, and its frequency did not increase in the time period under study. Regarding secondary glomerular diseases, apparent changes were noted in the incidence of a number of diseases, including vasculitis, thin glomerular basement membrane disease and Henoch-Schönlein pur-pura. A somewhat similar situation was noted with vascular and tubulointerstitial diseases. CONCLUSIONS: We conclude that, as occurs in other European and Asiatic populations, and unlike the findings in the American continent, IgA nephropathy is the most frequent glomerular disease in our population.

Adolescent↗