The Effect of Cobalt Chloride Pre-treatment on Experimental Ischemia-Reperfusion Renal Injury / 대한신장학회잡지

BACKGOUND: Cobalt chloride (COCL) has hypoxia-mimetic effects by inhibiting degradation of HIF-1alpha, which is a master regulator of genes activated by low oxygen tension. Heme oxygenase-1 (HO-1), an inducible heat shock protein, is known to have cytoprotective effects against ischemic injury. This study evaluated the efficacy of COCL in a bilateral renal ischemia-reperfusion (I-R) injury model of male Sprague-Dawley rats. METHODS: I-R renal injury was induced by 45 min clamping of both renal arteries. Rats in the sham (n=6) and I-R control groups (n=8) had been drinking tap water, whereas rats in the COCL treated sham (n=6) and COCL treated I-R groups (n=9) had been drinking water containing 2 mM COCL from day -10 to day 1. RESULTS: The serum level of creatinine 24 hrs after surgery was 2.6+/-1.1 (mean+/-SD) mg/dL in I-R COCL treated group, significantly lower than that in I-R control group (4.8+/-1.6 mg/dL, p<0.05). The renal HO-1 gene expression and protein signal were significantly upregulated in the COCL treated sham group compared to sham operated control rats (all, p<0.05). The expressions of TGF-beta MCP-1, TNF-alpha endothelin-1 and Fas genes in COCL treated I-R rats were significantly lower than those of I-R control rats (all, p<0.05). The level of Bcl-2 gene expression of COCL treated I-R rats was significantly higher than the level of I-R control rats (p<0.05). CONCLUSION: It is speculated that the pretreatment of COCL in I-R rat model attenuates ischemic renal injury and at least in part, upregulation of renal HO-1 is involved in this mechanism.

A Case of Reversible Posterior Leukoencephalopathy Syndrome in Patient with Chronic Renal Failure / 대한신장학회잡지

A Reversible Posterior Leukoencephalopathy Syndrome(RPLS) consists of neurologic symptoms and signs - headache, consciousness change, seizure, visual impairment - and brain imaging finding showing brain(espicially white matter) edema usually involving the posteior parietal-temporal-occipital areas. The causes are thought to be hypertensive encephalopathy, pre-eclampsia or eclampsia, renal failure with fluid overload and immunosuppressive agents such as cyclosporin A or FK506. RPLS may usually reversible if treated early by decreasing blood pressure and discontinuing offending drugs. A 23-year-old man had been hemodialyzed with chronic renal failure for two years. His blood pressure elevated to 240/150mmHg 3 days before admission and he complained of severe headache, vomiting, and total visual loss at the day of admission. Brain T2-weighted MRI imaging showed increased signal intensity involving the both parietal, posterior temporal, and occipital lobes. After antihypertensive and dexamethason treatment, a follow-up brain MRI performed on 7 days after admission showed nearly normalized findings and all symptoms including visual loss were recovered completely in one week.

A Case of Nephrotic Syndrome Complicated by the Thrombosis of Common Iliac Artery and Coronary Artery of Heart / 대한신장학회잡지

Thrombosis is one of the important complications of nephrotic syndrome. Still, the mechanism of thrombosis of nephrotic syndrome is under debate, but the presence of hypercoagulable state in nephrotic syndrome is regarded as the principal contributing factor to that. Venous thrombosis in nephrotic syndrome has been increasingly reported, but arterial thrombosis is relatively rare and has been reported mainly in nephrotic children. Authors experienced a 35-year old male patient with frequently relapsing nephrotic syndrome of focal segmental glomerulosclerosis, who complained sudden onset of claudication, cold sensation, numbness and cyanosis of right lower extremity. A diagnosis of thrombosis in right common iliac artery and thromboses in septal and distal branch of left anterior descending coronary artery was made by arterial angiography. The patient fully recovered after emergent thrombectomy and anticoagulation therapy.

Primary Sj gren's Syndrome Presenting with a Huge Pulmonary Mass and Acute Renal Insufficieney / 대한신장학회잡지

Sj gren's syndrome(SS) is a systemic autoimmune disorder characterized by lymphocytic infiltration of the lacrimal and salivary glands, which result in dry eye and dry mouth. Systemic involvement including the lungs, gastrointestinal tract, kidneys, endocrine glands, skin, or nervous system has been reported. Pulmonary abnormalities in SS are lymphoid interstitial infiltration, chronic bronchitis, pulmonary fibrosis and pleurisy. Pulmonary pseudolymphoma associated with acute renal insufficiency is very rare. Recently, we experienced a patient with SS presenting with a huge pulmonary mass in the left upper lobe and acute renal failure. Pulmonary pseudolymphoma and renal functional impairment were completely reversed after a six month treatment with oral prednisolon(1mg/kg, body weight) and monthly cyclophosphamide pulse therapy (12mg/kg, I.V.). There was no evidence of disease recurrence for 16 months after discontinuation of prednisolone therapy.

Renal Cortical TNF-alpha, TGF-beta, and Endothelin-1 Expression in Uni1ateral Renal Ischemia-Reperfusion Injured Rats / 대한신장학회잡지

Although the exact pathogenetic mechanisms of the renal ischemia-reperfusion injury(I-R injury) have not been clearly elucidated yet, the reactive oxygen spe-cies(ROS) and mononuclear cell infiltration have been suggested to contribute to this renal injury process. The cytokines and growth factors produced by infiltrated leukocytes and renal parenchymal cells could accelerate the process of tissue damage by inducing cellular proliferation, fibrosis, and further recruitment of other inflammatory cells. The renin-angiotensin sys- tem(RAS) also has been suggested to be one of the most important mediators in the renal injury process of many animal models and human renal diseases. In order to evaluate the change of the levels of TNF-alpha, endothelin-l, and TGF-beta gene expression in unilateral I-R injured renal cortical tissue, competitive RT-PCR was performed for the above mRNAs in Sprague-Dawley rats(60 minutes of ischemic time by non-traumatic vessel clamp and 24 hours of reperfusion). Also the plasma renin activity(PRA) and an-giotensin II(AII) level were measured at the time of sacrifice by radioimmunoassay. On the light miscroscopic examination, I-R injured renal cortical tissue showed typical findings of acute tubular necrosis, such as mononuclear ceU infiltration, necrosis, swelling and denudation of proximal tubular cells. Compared to control sham operated group, I-R injured group tissues showed significantiy increased level of TGF-beta(p<0.05), endothelin-l(p<0.05) and TNF-alpha(p<0.05) gene expression in 24 hours after I-R renal injury. The levels of PRA and AIl were also significantly elevated compared to sham group(p< 0.05, p<0.05, respectively). In conclusion, we speculate that the early activation of RAS and elevated gene expression of TNF-alpha, endothelin and TGF-beta of renal cortieal tissue may contribute to the early pathogenetic mechanism of I-R renal injury process.

A Case of Acute Cortical Necrosis in Patient with Polycystic Kidney Disease / 대한신장학회잡지

Acute cortical necrosis is a rare cause of the acute renal failure. It is frequently associated with complications of pregnancy. The renal biopsy is the key of diagnosis of these disease. However, the contrast enhanced CT scan can be a tool for the diagnosis of acute renal cortical necrosis, because of its noninvasiveness and constant findings(enhancement of subcapsular rim, nonenhancement of the renal cortex, enhancement of medulla, and lack of excretion of contrast media to the collecting system). This is a case of acute renal cortical necrosis diagnosed by CT scan. She had an anuria for 16 days and feature of hemolytic uremic syndrome and polycystic kidney.