8283 Diabetes Mellitus in Patients with Hemochromatosis- A Diagnostic and Therapeutic Challenge

Abstract Disclosure: U. Rafat: None. M. Siddiqui: None. J.L. Gilden: Other; Self; Novartis Pharmaceuticals. A. Moid: Other; Self; Novartis Pharmaceuticals. Background: Primary Hemochromatosis is a genetic condition most commonly due to two sets of mutations in the Human homeostatic iron regular Protein (HFE) gene. HFE modulates the expression of hepcidin, which regulates intestinal iron absorption, plasma iron concentration and distribution of iron in tissues. Hemochromatosis patients are at high risk for developing diabetes mellitus (DM) due to iron overload in the pancreas with damage to Beta cells and impaired insulin secretory capacity. Hemochromatosis is often called Bronze Diabetes due to brown discoloration of the skin from accumulation of iron, and is characterized by hepatic fibrosis, fatigue, arthralgias, cirrhosis, DM, arthropathy, pigmentation and cardiomyopathy. Case: We present a Caucasian male with homozygous hereditary hemochromatosis, diagnosed by liver biopsy at age 40 due to transaminitis and Ferritin level of 1500 ng/mL and Genetic testing- 2 copies of HFE gene pathogenic variant (C282Y). He was later diagnosed with DM age 51, started on Metformin and referred to Endocrine clinic with abdominal bloating, and polyarticular arthralgias. Physical exam=Vital Signs normal (WT. 231lbs, BMI 34), with splenomegaly, but normal musculoskeletal exam and skin without bronze discoloration. Both parents had T2DM. Lab- Hb a1c 8.7% (0.0-5.6), Iron saturation 71% (10-50), Ferritin 66.3 ng/mL (26-388), C-Peptide 3.30 ng/ml (0.81-3.85), with glucose level of 119 mg/dL, and negative IA-2 <5.4 U/mL, negative Islet cell antibody, GAD 65 <5 IU/mL (nl <5), Insulin Autoantibody <0.4 U/mL (nl <0.4), and Zinc Transporter 8 antibodies <10 U/mL (nl <15). Liver tests- AST 39 U/L(10-37), ALT 77 U/L (10-65), ALP 89 U/L (45-117), total bilirubin 1.1 mg/dL(0.2-1.2). Hormonal evaluation included TSH 1.2 uIU/mL (0.55-4.78), ACTH 19 pg/mL (0-47), AM Cortisol 16.28 ug/d (5.30-22.50) IGF1 158 ng/mL (50-317) FSH 9.6 mIU/mL(l.40-18.10), LH 5.09 mIU/mL (1.50-9.30), Prolactin 7.40 ng/mL(2.10-17.70), total testosterone 374 ng/dL(250-1100), free testosterone 66.2 pg/mL (35.0-155.0). Echocardiogram-left ventricular hypertrophy and thick right ventricular wall with concerns for iron overload. Hba1c improved to 6.6% on Metformin. Fructosamine 351umol/L (151-300). In the absence of advanced cardiac, hepatic and other organ involvement, and presence of elevated C-peptide and high BMI, this patient is being managed as T2DM, with low threshold to initiate insulin therapy considering possibility of concomitant Bronze DM. Conclusion: It is important to determine type of DM, so appropriate management options can be devised. While insulin is recommended for management in Bronze Diabetes, insulin sensitizers, such as metformin and/or GLP 1 agonists can be used in type 2 DM. One must also consider therapy based upon the risk of cancer and acute pancreatitis in the setting of pancreatic iron overload, when considering antihyperglycemic therapies. Presentation: 6/2/2024