Search PubMed⌕ Search

Biomedical subjects

Hiroyuki Ohi

Publications and source records attributed to Hiroyuki Ohi.

6 recordsLinked to original sources

Autoimmune hemolytic anemia occurred prior to evident nephropathy in a patient with chronic hepatitis C virus infection: case report.

BACKGROUND: Renal involvement in patients with chronic hepatitis C virus infection has been suggested to be due to a variety of immunological processes. However, the precise mechanism by which the kidneys are damaged in these patients is still unclear. CASE PRESENTATION: A 66 year old man presented with the sudden onset of autoimmune hemolytic anemia. Concomitant with a worsening of hemolysis, his initially mild proteinuria and hemoglobinuria progressed. On admission, laboratory tests revealed that he was positive for hepatitis C virus in his blood, though his liver function tests were all normal. The patient displayed cryoglobulinemia and hypocomplementemia with cold activation, and exhibited a biological false positive of syphilic test. Renal biopsy specimens showed signs of immune complex type nephropathy with hemosiderin deposition in the tubular epithelial cells. CONCLUSIONS: The renal histological findings in this case are consistent with the deposition of immune complexes and hemolytic products, which might have occurred as a result of the patient's underlying autoimmune imbalance, autoimmune hemolytic anemia, and chronic hepatitis C virus infection.

Aged↗

Recombinant EPO therapy increases erythrocyte expression of complement regulatory proteins.

BACKGROUND: One of the complications of hemodialysis (HD) therapy is anemia caused by erythropoietin (EPO) deficiency. Recombinant EPO (rEPO) has been used routinely as a supplemental treatment. Erythrocyte expression of the complement regulatory proteins decay accelerating factor (DAF) and CD59 restricts complement activation and inhibits hemolysis. We hypothesized that the efficacy of rEPO treatment may be caused in part by the ability of rEPO to increase erythrocyte expression of DAF and CD59. METHODS: DAF, CD59, and complement receptor 1 (CR1) levels were analyzed for a group of 95 HD patients and compared with those of a control group. To evaluate effects of discontinuation of rEPO therapy, rEPO therapy was stopped for 12 HD patients until hematocrits decreased to less than 25%. DAF and CD59 levels then were reanalyzed. RESULTS: In the 95 HD patients, three factors correlated significantly: DAF and CD59 (r = 0.642), DAF and CR1 (r = 0.503), and CD59 and CR1 (r = 0.324), whereas no correlations were found in the group of 42 healthy controls. In the experiment in which rEPO therapy was discontinued, 8 of 12 patients reached the defined level of anemia 4 to 7 weeks after rEPO treatment had been withheld. Both DAF and CD59 levels decreased significantly after discontinuation of rEPO therapy (P < 0.01). DAF and CD59 levels increased in all 8 patients after rEPO treatment was reinitiated (P < 0.01), and CR1 levels increased in 5 of 8 patients. Four of 12 patients showed no evidence of anemia after discontinuation of rEPO treatment. In these patients, DAF, CD59, and CR1 levels did not change before or after withholding rEPO therapy. CONCLUSION: One of the mechanisms mediating the efficacy of EPO therapy is increased DAF and CD59 expression.

Anemia↗

Significant elevations in serum mannose-binding lectin levels in patients with chronic renal failure.

BACKGROUND/AIMS: Mannose-binding lectin (MBL), a liver-derived C-type serum lectin, activates the complement cascade through the lectin pathway. Since the complement system contributes to the host defense against infections and mediates inflammatory processes including atherosclerosis, and since chronic renal failure (CRF) patients are prone to the development of infectious complications and cardiovascular disease, we focused on serum MBL levels in CRF patients who were either uremic, or who were receiving hemodialysis treatment. METHODS: MBL levels were measured in the sera of subjects with CRF before they began dialysis treatment (pre-HD patients; n = 23) and in the sera of subjects who were receiving maintenance hemodialysis (HD patients; n = 178), by ELISA using polyclonal anti-rabbit IgG and a monoclonal antibody directed against MBL (3E7). METHODS: Mean levels (+/- SD) of serum MBL were significantly higher in pre-HD subjects (4.343 +/- 2.533 microg/ml, p < 0.05) and in HD subjects (8.897 +/- 4.920 microg/ml, p < 0.05), than in healthy controls (1.452 +/- 0.692 microg/ml). Levels were also significantly higher in HD subjects than in pre-HD subjects (p < 0.05). CONCLUSIONS: Elevated serum MBL levels in patients with CRF might have significantly influence pathologic conditions such as alterations of the immune system and acceleration of atherogenesis.

Adult↗

Urinary complement factor H in renal disease.

BACKGROUND: Complement factor H (hCFH) plays a key inhibitory role in the control of the alternative complement pathway. We examined whether urinary hCFH (U-hCFH) levels is useful as an indirect indicator of renal damage. METHODS: Urine samples were obtained from 104 patients with renal disease. Urine was collected with 10 mM EDTA and U-hCFH levels were measured using the BTA TRAK Assay Kit. RESULTS: In the 62 patients with nephritis, the levels of U-hCFH were elevated (range 15-52,198 U/ml) over the normal range (0-14 U/ml). U-hCFH levels of patients with chronic renal failure, lupus nephritis, membranoproliferative glomerulonephritis, focal glomerulosclerosis were higher than that of IgA nephropathy patients (p < 0.05). In the patients with minimal change disease, showed high levels of U-hCFH during the nephrotic syndrome. U-hCFH was correlated significantly with urinary protein and urinary N-acetyl-beta-D-glucosaminidase. CONCLUSIONS: We demonstrated that U-hCFH was detected in the urine of nephritis patients.

Biomarkers↗

Nephrotic syndrome with portal, splenic and renal vein thrombosis. A case report.

BACKGROUND: Thromboembolism is known as a major complication of nephrotic syndrome, but only 4 cases of portal vein thrombosis have been reported as a complication of nephrotic syndrome. All of these 4 cases had acute symptoms, and 3 of 4 were in relapsing phase of nephrotic syndrome when thrombi were found. We describe here a case of 51-year-old woman with fresh nephrotic syndrome that was asymptomatically complicated by portal, splenic and renal vein thrombosis. CONCLUSIONS: In the presence of fresh nephrotic syndrome of minimal change, asymptomatic and widely distributed, including portal vein, thrombus formation occurred. If the clinical course shows resistance to therapy, we must consider the complication of venous thrombosis. Anticoagulant therapy with heparin and warfarin was effective and all thrombi disappeared without any other complications.

Acute Disease↗