Hemochromatosis
A genetic disorder causing toxic iron overload in organs (liver, heart, pancreas) due to HFE gene mutations leading to hepcidin deficiency.
Emergency Management: Vibrio vulnificus septicemia requires immediate, aggressive broad-spectrum antibiotics (e.g., Ceftriaxone + Doxycycline) and ICU supportive care.
Hereditary hemochromatosis (HH) is an autosomal recessive genetic disorder characterized by excessive intestinal absorption of dietary iron, leading to pathological iron deposition in multiple parenchymal organs. The resulting iron overload causes tissue damage and organ dysfunction, most notably in the liver, pancreas, heart, joints, and pituitary gland.
Detailed Overview
HH is one of the most common genetic disorders in individuals of Northern European descent. The most prevalent form is caused by a C282Y mutation in the HFE gene, which severely impairs the production of hepcidin, the master iron-regulatory hormone. Because humans lack a physiological pathway to excrete excess iron, the unregulated absorption results in progressive iron accumulation. Decades of iron deposition lead to classic manifestations such as cirrhosis, 'bronze diabetes', and restrictive cardiomyopathy. Early diagnosis is critical because therapeutic phlebotomy can prevent organ damage and restore normal life expectancy.
Epidemiology & Demographics
Incidence/Prevalence: 1 in 200 to 1 in 300 individuals of Northern European (Celtic) ancestry are homozygous for the C282Y mutation. Age distribution: Symptoms typically present in men at 40-50 years and in women at 50-60 years (post-menopause). Gender ratio: Men are affected earlier and more severely than women due to physiological blood loss in women (menstruation, pregnancy).
Etiological Mechanism
Autosomal recessive mutation in the HFE gene located on chromosome 6. The most common genotype is C282Y homozygosity (accounting for 80-90% of clinical HH cases).
Primary Causes
Primary: Homozygous C282Y mutation in the HFE gene, or compound heterozygous C282Y/H63D mutations
Secondary: Non-HFE mutations (e.g., Hemojuvelin, Hepcidin, Transferrin receptor 2) causing juvenile or rarer forms of hemochromatosis
In a healthy individual, the liver peptide hepcidin binds to ferroportin (the iron exporter on intestinal enterocytes and macrophages), inducing its internalization and degradation, thereby halting iron absorption into the blood. In HFE-hemochromatosis, the mutated HFE protein fails to complex properly with the transferrin receptor, leading to a false 'low iron' signal to the hepatocytes. Consequently, hepcidin production is drastically reduced. Without hepcidin, ferroportin remains constantly active on the basolateral membrane of enterocytes, resulting in uninhibited iron absorption. Iron saturates circulating transferrin, and non-transferrin-bound iron (NTBI) emerges in the plasma. NTBI is rapidly taken up by parenchymal cells of the liver, pancreas, and heart. Inside these cells, excess iron catalyzes the Fenton reaction, generating highly reactive hydroxyl radicals. This oxidative stress causes lipid peroxidation, DNA damage, and ultimately cell death and fibrosis (e.g., cirrhosis, pancreatic beta-cell destruction).
Diagnostic Criteria & Guidelines
Initial screening requires fasting Transferrin Saturation (>45%) and elevated Serum Ferritin (>300 ng/mL in men, >200 ng/mL in women). Diagnosis is confirmed by HFE genetic testing revealing C282Y homozygosity. Liver biopsy is reserved for patients with Ferritin > 1000 ng/mL or elevated liver enzymes to assess for cirrhosis.
Therapeutic Phlebotomy: Removal of 500 mL of whole blood (contains ~200-250 mg iron) once or twice weekly until serum ferritin is 50-100 ng/mL. Maintenance phlebotomy every 2-4 months thereafter to keep ferritin < 50-100 ng/mL.
Second-Line & Adjunctive Therapy
For patients intolerant to phlebotomy (e.g., severe anemia, heart failure): Iron chelation therapy with Deferasirox 10-20 mg/kg/day PO or Deferoxamine SC/IV.
Surgical & Procedural Management
Liver transplantation for decompensated cirrhosis or early-stage Hepatocellular Carcinoma (HCC). Joint replacement (arthroplasty) for severe, debilitating arthropathy.
Patient Counseling & Advice
Educate the patient that hemochromatosis is highly manageable and normal life expectancy is expected if treatment begins before cirrhosis develops. Emphasize the necessity of lifelong maintenance phlebotomy. Strongly recommend screening for first-degree relatives (siblings, children) via iron panel and HFE genetic testing.
Follow-Up & Monitoring Schedule
Check Hemoglobin and Ferritin prior to every phlebotomy during induction. Once at maintenance, monitor Ferritin every 3-6 months. For patients with cirrhosis, routine HCC screening with hepatic ultrasound and AFP every 6 months is mandatory.
Preventive Strategies
Primary prevention involves genetic screening of first-degree relatives to initiate phlebotomy before iron loading damages organs.
Normal life expectancy if phlebotomy is initiated before the onset of cirrhosis or diabetes. If cirrhosis is present at diagnosis, life expectancy is reduced and HCC risk is high.