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.

Initial functional status predicts infections during steroid therapy for renal diseases

BACKGROUND AND AIM

Corticosteroid therapy is an effective way of treatment for many renal diseases, however, it is sometimes associated with infections. Our aim is to identify useful predictive markers of infection during steroid therapy.

METHODS

We examined 121 patients (M/F = 71/50, mean age 43.8, range 15 - 82 years) who were treated with corticosteroids (IgA nephropathy in 51, minimal-change disease in 17, membranous nephropathy in 16 rapidly progressive glomerulonephritis (RPGN) in 13, lupus nephritis in 12 and other disorders in 12). Karnofsky's performance score (KPS) was employed to assess the physical functional status at the time of diagnosis. Infections were defined as conditions that required more than 1-week care, and those that caused the patient's death.

RESULTS

Nineteen patients (15.7%) had infections during treatment. A logistic multivariate analysis showed significant correlations between infection and the use of immunosuppressive agents (relative risk RR = 7.7, p = 0.0265), ages of 52.9 years or more (RR = 13.5, p = 0.0026), initial number of lymphocytes (Lym) less than 1.250/microl (RR = 14.2, p = 0.0011), and KPS less than 77.4 (RR = 12.1, p = 0.0020). All correlations with infection were independent of all the other variables listed above.

CONCLUSION

KPS, along with age, Lym and the use of immunosuppressive agents, are useful for the prediction of infectious complications during steroid therapy.

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.

Close relationship of plasminogen activator inhibitor-1 4G/5G polymorphism and progression of IgA nephropathy

BACKGROUND

The plasminogen activator inhibitor-1 (PAI-1) 4G/4G genotype influences the development of diabetic nephropathy and lupus nephritis. However, the association of the PAI-1 4G/4G genotype and IgA nephropathy (IgAN) has not been investigated.

SUBJECTS AND METHODS

The PAI-1 and ACE polymorphisms were examined in 270 healthy volunteers and 202 biopsy-proven IgAN patients, including 117 untreated IgAN patients who had an annual health check, allowing an estimation of the time of onset of overt proteinuria and/or hematuria. The relationship between the gene polymorphisms and the pathogenesis of IgAN were examined in 202 IgAN patients and the relationship between the gene polymorphisms clinical and pathohistological findings were examined in 117 untreated IgAN patients cross-sectionally at the time of renal biopsy.

RESULTS

202 IgAN patients and 117 untreated IgAN patients did not have different frequencies in PAI-1 4G/5G (4G/4G : 4G/5 : 5G/5G = 82 : 90: 30, 45 : 55 : 17) and ACE I/D (DD : ID : II = 41 : 82 : 79, 21 : 54 : 42) gene polymorphisms compared with 270 healthy volunteers (4G/4G : 4G/5 : 5G/5G = 99 : 124 : 47, DD : ID : II = 53 : 106 : 111). However, IgAN with 4G/4G had significantly more advanced histological changes than IgAN with 4G/5G or 5G/5G both in glomerular and tubulointerstitial findings (p < 0.0005). The disease duration in IgAN with 4G/4G was shorter than in IgAN with 4G/5G + 5G/5G (6.22 +/- 6.38 and 8.80 +/- 9.79 years, respectively, p < 0.05). Creatinine clearance (Ccr) in IgAN with 4G/4G was significantly lower than IgAN with 4G/5G or 5G/5G (72.3 +/- 26.5 and 82.4 +/- 22.8 ml/min, respectively, p < 0.05). The mean urinary protein excretion in IgAN with 4G/4G was significantly more than in IgAN with 4G/5G or 5G/5G (1.10 +/- 1.48 and 0.70 +/- 1.01 g/day, respectively, p < 0.05). There was no difference between IgAN with the DD ACE genotype and IgAN with ID + II genotypes in either the clinical or histopathological findings.

CONCLUSION

PAI-1 polymorphism is not associated with genesis of IgA nephropathy, but may be a risk factor for the progression of IgA nephropathy in Japanese.

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.

Insulin resistance highly associates with hypertension in IgA nephropathy

BACKGROUND

Insulin resistance has been reported to induce hypertension. Previous studies described that there was no relationship between insulin resistance and hypertension in patients with chronic renal diseases with mild to moderate renal dysfunction. The aim of the present study is to clarify the relationship between insulin resistance and blood pressure, renal function, histopathological changes and other characteristics in IgA nephropathy (IgAN).

METHODS

Eighty-eight IgAN patients were included in this cross-sectional study. Hypertension was diagnosed according to the WHO/ISH criteria. Insulin resistance was evaluated by homeostasis model assessment (HOMA-IR).

RESULTS

Male gender, age, body mass index, serum creatinine, urinary protein excretion, triglycerides and HOMA-IR were positively correlated with hypertension. C(Cr), serum albumin and HDL cholesterol were negatively correlated with blood pressure by Spearman's simple correlation test. By logistic multivariate analysis, C(Cr), insulin resistance, age and male gender were significantly correlated with hypertension, independently of all other variables.

CONCLUSIONS

Insulin resistance is not directly related to renal dysfunction, but is also independently associated with hypertension in IgAN. Since hypertension is considered as a risk factor for renal disease progression, insulin resistance may be an indirect deteriorating factor for IgAN. To identify and improve insulin resistance may be another therapeutic target in the clinical management of 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.