Pathological findings of progressive renal involvement in a patient with TAFRO syndrome.

TAFRO syndrome (thrombocytopenia, anasarca, fever, reticulin fibrosis, and organomegaly) is thought of as an atypical type of idiopathic multicentric Castleman's disease. Interleukin-6, vascular endothelial growth factor (VEGF), and other cytokines are considered etiological factors. A 45-year-old woman was admitted to hospital with unknown fever and abdominal pain. She had thrombocytopenia, anasarca, proteinuria/hematuria, and slight hepatosplenomegaly. Based on her clinical course and laboratory data, she was diagnosed as having TAFRO syndrome. Kidney biopsy showed a membranoproliferative glomerulonephritis (MPGN)-like lesion containing lobulations of glomeruli, endothelial cell swelling, double contours of the glomerular basement membrane, and mesangiolysis. She was treated with methylprednisolone pulse (500 mg/day) and oral prednisolone (60 mg/day) therapy. The pleural effusion and ascites disappeared, and renal function normalized. Cyclosporine was added to prevent relapse. She went home, with no relapse 8 months after hospitalization. MPGN-like lesions were found frequently in patients with TAFRO syndrome in recent reports. However, there are few reports of pathologically confirmed cases of progressive renal involvement in TAFRO syndrome. The relationship between VEGF expression in renal tissue and the pathogenesis of renal injury in TAFRO syndrome was investigated in the present case.

Risk factors for bleeding complications in percutaneous renal biopsy.

BACKGROUND: Among the complications in percutaneous renal biopsy, bleeding is the most frequent and sometimes becomes fatal. METHODS: We prospectively studied 394 consecutive percutaneous renal biopsies in 359 patients (male/female = 188/171). The mean age of the patients was 44.0 +/- 17.2 years. Percutaneous renal biopsies were performed on native kidneys under direct visualization by ultrasound, using an automated spring-loaded biopsy device and a 16-cm 18 G needle. RESULTS: The most common complication was hematoma (n = 149, 37.8%). "De novo macrohematuria" was observed in 29 patients (7.4%). Other complications included pain (n = 27, 6.9%), loss of blood (n = 17, 4.3%), and renal dysfunction (increase of serum creatinine more than 0.2 mg/dl, n = 9, 2.2%). Although there were no severe complications such as loss of blood requiring a blood transfusion, loss of kidney function, or death, 10 patients had an extended rest period in bed because of moderate complications. Hypertension and amyloidosis had significant influence on the complications. CONCLUSIONS: For those who are clinically suspected of having amyloidosis or hypertension, more careful biopsy procedures and observations are necessary.

Effects of salt loading on blood pressure in mice lacking the prostanoid receptor gene.

BACKGROUND: This study examined whether targeted disruption of the genes for the prostacyclin receptor (IP) or the thromboxane A2 receptor (TP) confers a susceptibility to salt-dependent hypertension. METHODS AND RESULTS: Eight female IP- or TP-deficient mice were examined. Baseline systolic blood pressure (SBP) did not differ between TP(-/-) and TP(+/+), but was significantly lower in the IP(-/-) group than in the IP(+/+). With a high salt diet, SBP in IP(-/-) gradually increased. In contrast, SBP in the IP(+/+), TP(-/-), or TP(+/+) groups remained unchanged. CONCLUSIONS: The prostacyclin receptor may participate in the maintenance of baseline BP. With salt loading, BP adaptation may take place, at least in part, via IP mediated signals.

Steroid therapy reduces mesangial matrix accumulation in advanced IgA nephropathy.

BACKGROUND: Steroid therapy for IgA nephropathy (IgAN) has been reported to ameliorate the long-term prognosis of IgAN, but its mode of action has not been fully elucidated. In this study, we examined the effect of steroids on glomerular morphological changes in IgAN. METHODS: We examined 16 patients with biopsy-proven IgAN (male/female =11/5, mean age 32.1 years) who were divided into prognosis groups according to criteria set by the Japanese Society of Nephrology. Initially, they received a loading dose of steroids, followed by a daily dose of 10-15 mg prednisolone. After 12 months, they underwent a second biopsy, and their histological and clinical features were examined. RESULTS: Before and after therapy, systolic blood pressure, diastolic blood pressure, serum creatinine and creatinine clearance all remained unchanged. However, urinary protein excretion decreased dramatically, from 1.6+/-1.7 to 0.4+/-0.2 g/day (P<0.005). Furthermore, computerized imaging revealed a significant reduction of the mesangial matrix index (MMI) from 14.5+/-5.2 to 9.5+/-3.6% (P<0.001). The numbers of sclerosing glomeruli did not change. CONCLUSIONS: Steroid therapy reduces mesangial matrix accumulation and reduces urinary protein excretion in advanced IgAN.

The product of duration and amount of proteinuria (proteinuria index) is a possible marker for glomerular and tubulointerstitial damage in IgA nephropathy.

BACKGROUND/AIMS: IgA nephropathy (IgAN) is one of the major causes for chronic renal failure (CRF). Presence of massive proteinuria, hypertension, increased serum creatinine level and sclerotic histopathological changes of the glomerulus are known to be determinants for the progression of CRF. However, the relationships between duration of proteinuria/hematuria and histopathological changes, which may be correlated with the renal prognosis, have not been clarified. METHODS: A cross-sectional, univariate analysis of clinical parameters on the four glomerular and three tubulointerstitial histopathological grades in 57 untreated biopsy-proven IgAN patients (M/F = 32/25) was performed. RESULTS: The age at the time of renal biopsy (35.2 +/- 13.0 years; mean +/- SD), average duration of proteinuria (5.3 +/- 5.8 years), mean urinary protein excretion (0.99 +/- 1.22 g/day), serum creatinine (Cr 0.97 +/- 0.28 mg/dl), Cr clearance (Ccr 75.5 +/- 29.4 ml/min), and blood urea nitrogen (BUN 15.4 +/- 3.9 mg/dl) were well correlated with both histopathological grades. The product of duration (years) and urinary protein excretion (g/day) at the time of renal biopsy was more significantly correlated with glomerular and tubulointerstitial histopathological grades and serum Cr. CONCLUSION: The natural course of IgAN is steadily progressive depending on the duration and amount of proteinuria. The product of these two factors (proteinuria index) may be a useful predictor for glomerular and interstitial histopathological changes and the fate of renal function in IgAN.