S1818 Rare Sequelae of Obstructive Jaundice: Hyperferritinemia and Bile Cast Nephropathy

Abstract

Introduction: Obstructive jaundice occurs due to a physical blockage in the biliary outflow tract or external compression. While jaundice and scleral icterus are common symptoms initially, long term sequelae include severe systemic manifestations from the buildup of various compounds normally excreted in bile such as bilirubin. Case Description/Methods: A 67-year-old male smoker presented with 3 weeks of pruritus, acholic stools, dark urine, nausea, vomiting, and 20-pound weight loss. Physical exam was notable for jaundice and scleral icterus, LUQ and epigastric tenderness to palpation, but lacked hepatosplenomegaly, ascites or other stigmata of cirrhosis. Liver function tests showed AST 486 IU/L, Alk Phos 1419 IU/L, Alt 600 IU/L, and total bilirubin >30.0 mg/dL with direct bilirubin >10.0 mg/dL. Ferritin was >7500 ng/mL with decreased transferrin of 159 mcg/dL. Hepatitis panel and malignancy/autoimmune markers were negative. CMP showed BUN 74 mg/dL, and creatinine 5.1 mg/dL with 2+bilirubin on urinalysis and microscopic analysis showing pigmented renal tubular cells, bilirubin crystals, and waxy casts suggestive of ATN due to bilirubin damage and possible CKD given waxy casts (Table). CT abdomen reported severe intra and extra hepatic biliary duct dilation with CBD of 17 mm and abrupt tapering with pancreatic head fullness confirmed with MRCP. On day 2, ERCP showed a tight 15mm distal biliary stricture. A small sphincterotomy followed by balloon dilation allowed for placement of a CBD stent with excellent drainage of dark green bile. Following ERCP, patient had a drop of liver function tests and ferritin levels, gradual improvement in BUN and creatinine, and was discharged in stable condition on hospital day 6. On day 16, EUS revealed a hypoechoic area within the periampullary area with atypical cells in brushings collected during repeat ERCP (Figure). Discussion: Iron and iron binding proteins have been shown to be excreted in bile, primarily in iron excess. Our patient showed a large increase in ferritin signifying the potential role of biliary excretion of excess ferritin, with unknown ramifications. Additionally, severe biliary tree obstruction led to markedly elevated bilirubin, overwhelming renal clearance leading to severe tubular damage. With alleviation of obstruction, there was a steady decrease in ferritin and return to normal baseline renal function. Further research is needed to clarify both the consequences of excess ferritin in biliary obstruction and the significance of excess bilirubin in renal injury.Figure 1.: a) Ampulla prior to ERCP on day 2 shows no periampullary abnormality. b) Day 16 - Endoscopic Ultrasound showing narrowing of distal common bile duct with hypoechoic intraductal area. c) Bile casts and bilirubin crystals seen on microscopy. Table 1. - Patient’s Laboratory test results on and post admission Laboratory Values Reference Range Day 1 Day 5 (3 days post-ERCP) Day 21 AST 13 – 39 IU/L 486 187 18 ALT 7 – 52 IU/L 600 315 27 Alkaline Phosphatase 34 – 104 IU/L 1419 886 160 Total Bilirubin 0.3 - 1.2 mg/dL >30.0 13.0 4.4 Albumin 3.5 - 5.2 g/ 3.0 2.9 3.4 BUN 7 – 25 mg/dL 74 64 18 Creatinine 0.5 - 1.2 mg/dL 5.1 2.90 1.01 WBC 4 – 11 K/cmm 13.8 17.7 10.1 Hgb 13.7 - 17.5 g/dL 11.9 9.4 8.5 Ferritin 24 – 336 >7500 4677 976 Transferrin 300 to 360 mcg/dL 159 233 Iron 50 - 182 ug/dL 126 61 Iron Saturation 57% 19% TIBC 250 – 450 ug/dl 233 326 Urine Bilirubin Negative 2+ Negative Urobilinogen 0.0 - 2.0 EU/dL 4.0 < 2.0 PT 9.1 - 13.2 sec 26.6 12.8 PTT 23.3 - 36.6 SEC 42.0 33.0 INR 0.8 - 1.2 2.3 1.1 Alpha-1-Antitrypsin (ATT) 83 – 199 mg/dL 256 Ceruloplasmin 18– 36 mg/dL 51 Carcinoembryonic Antigen (CEA) 0.0 - 3.0 ng/mL 3.9