Podocyte Injury in Autosomal Dominant Polycystic Kidney Disease.

BACKGROUND/AIMS: Autosomal dominant polycystic kidney disease (ADPKD) is a tubulointerstitial disease. Different degrees of glomerular affection in ADPKD may affect the further course of disease in which it may hypothetically be secondary to the result of glomerular involvement causing podocyte injury. Our aim was to compare urinary excretion of podocin and podocalyxin, which are biomarkers of podocyte injury, and to assess their relationship with proteinuria and renal function in ADPKD. METHODS: Fifty-six patients with ADPKD and 28 volunteers were enrolled to study. Podocin, podocalyxin protein levels, and proteinuria were measured in urine. Patients were categorized based on their estimated glomerular filtration rate (eGFR). RESULTS: Patients with ADPKD had higher podocin and podocalyxin levels compared to the control group. The levels of podocin and podocalyxin were higher in ADPKD patients both with eGFR ≥60 mL/min/1.73 m2 and with eGFR <60 mL/min/1.73 m2 than in controls. The levels of podocin and podocalyxin were higher in ADPKD patients with eGFR <60 mL/min/1.73 m2 than in ADPKD patients with eGFR ≥60 mL/min/1.73 m2. Podocin and podocalyxin were negatively correlated with eGFR and positively correlated with urine protein to creatinine ratio in ADPKD patients. CONCLUSION: Urine biomarkers of podocytes injury were significantly higher in ADPKD patients even in the early stage of the disease than in the control group. It should be clarified whether these biomarkers can provide new prognostic parameters for disease surveillance.

Bilateral Ischemic Optic Neuropathy Developed under Interferon Therapy.

Introduction. Interferon is a glycoprotein produced by assigned cells of immune system. It has been used in many different diseases. Although flu-like syndrome, myalgia, rash, hypotension, thrombocytopenia and peripheral neuropathy due to interferon use are encountered frequently, ocular side effects are rare, generally mild and transient. Case Report. 47-year-old female patient, presented with a mass lesion in right renal pelvis. Right radical nephrectomy was applied and the histopathological examination was consistent with papillary renal cell carcinoma. Interferon alpha treatment was started subcutaneously at the dose of 5 MIU/3 times in a week. Four weeks after the interferon therapy, suddenly bilateral visual loss developed. We discussed the diagnosis, followup, and treatment of the patient who developed irreversible ischemic optic neuropathy and had no previous known primary systemic disease to cause this condition. Conclusion. We suggest that patients should be screened for risk factors causing optic ischemic neuropathy, before interferon therapy. Although there was no adequate information in the literature for the followup, patients should be monitorized before, 1 month after, and 2 months after the treatment. And if there is no complication, we suggest that they should be followed up at 3-month intervals.