Inherited Liver Disease

Slide 1 · Inherited Liver Disease

Iron overload · Copper accumulation · Protein misfolding

Iron overload

Copper retention

Protein misfolding

Dr Abu Suraih Sakhri

MBBS, MD (Pathology)

www.abusuraihsakhri.com

Slide 2 · Learning objectives

Distinguish iron overload, copper transport failure, and α1-antitrypsin misfolding.

Connect each molecular defect to liver injury and extrahepatic disease.

Recognize characteristic histologic patterns and their limitations.

Select appropriate diagnostic approaches and explain clinical implications.

Slide 3 · Three diseases, three mechanisms

Hemochromatosis

Increased intestinal iron delivery

Hepatic iron deposition → oxidant injury

Wilson disease

Failed ATP7B-mediated copper handling

Toxic copper retention → hepatic / neural injury

α1-Antitrypsin deficiency

Misfolded secretory protein retained in ER

Hepatocyte proteotoxic stress

Slide 4 · What is inherited—and what is injured?

Disorder

Primary lesion

Hepatic consequence

Hemochromatosis

Iron regulatory genes; hepcidin axis

Hemosiderin deposition, fibrosis, cirrhosis

Wilson disease

ATP7B copper-transport ATPase

Variable hepatocyte injury, hepatitis, cirrhosis

α1-Antitrypsin deficiency

PiZ misfolding phenotype

ER retention, inclusions, chronic liver injury

Slide 5 · Inheritance does not predict phenotype alone

Gene variant and zygosity influence the biochemical abnormality.

Clinical penetrance is incomplete in common HFE genotypes.

Not every PiZZ individual develops clinically overt liver disease.

The magnitude and duration of tissue accumulation shape organ damage.

Slide 6 · Three routes to hepatocyte damage

Genetic defect

Metal excess or protein retention

Cell stress / injury

Fibrosis or organ dysfunction

Different initiating defects converge on progressive tissue injury.

Slide 7 · Hemochromatosis: Systemic iron overload

Excessive intestinal iron absorption drives iron accumulation.

Liver and pancreas are major sites of deposition; Other organs follow.

Inherited forms are hereditary hemochromatosis.

Transfusional and other acquired causes produce secondary iron overload.

Slide 8 · Hereditary versus secondary overload

Hereditary hemochromatosis

Secondary hemochromatosis

Usually disrupted iron sensing / hepcidin regulation

Repeated transfusions or increased intestinal iron uptake

Commonly HFE-associated adult phenotype

Ineffective erythropoiesis, severe thalassemias, marrow disease

Iron loads accumulate over years

May occur independently of hereditary hepcidin defects

Slide 9 · Hepcidin is the iron-export brake

Hepatocyte produces hepcidin

Hepcidin binds ferroportin

Ferroportin is internalized

Less iron exits enterocytes / macrophages

Normal negative feedback prevents excessive plasma iron delivery.

Slide 10 · Ferroportin connects gut and plasma

Intestinal enterocyte

Absorbs dietary iron

Ferroportin exports iron to plasma

Hepcidin restricts export

Macrophage

Recycles iron from erythrocytes

Ferroportin releases recycled iron

Hepcidin restricts export

Slide 11 · The hereditary hemochromatosis genes

Gene / protein

Normal role

Disease association

HFE

Supports hepatic hepcidin synthesis

Most common adult hereditary form

TFR2 / transferrin receptor 2

Iron sensing / hepcidin regulation

Rare hereditary form

HJV / hemojuvelin

Hepcidin regulation

Juvenile hemochromatosis

HAMP / hepcidin

Hormonal inhibition of ferroportin

Rare juvenile form

SLC40A1 / ferroportin

Cellular iron efflux

Rare ferroportin-related disease

Slide 12 · When hepcidin feedback fails

Iron-sensing defect

Inadequate hepcidin action

Ferroportin remains active

Persistent plasma iron delivery

Excess iron eventually deposits in parenchymal organs.

Slide 13 · HFE genotype does not equal clinical disease

C282Y is the predominant HFE mutation among diagnosed hereditary cases.

C282Y homozygosity is commoner than clinically manifest disease.

The excerpt estimates iron-overload evidence in only about 10% of homozygous males.

Penetrance is even lower in female C282Y homozygotes and H63D-associated genotypes.

Slide 14 · Why manifestations often occur later

Inherited iron uptake defect

From early life

Net iron accumulation

Progresses over decades

Tissue toxicity

Often middle adulthood

Menstrual iron losses can delay clinically important iron accumulation.

Slide 15 · Iron accumulation: Organ distribution

IRON OVERLOAD

Liver

Cirrhosis

Pancreas

Diabetes / fibrosis

Heart

Myocardial dysfunction

Endocrine / joints

Hypogonadism / arthropathy

Slide 16 · Iron toxicity has three principal effects

Free radicals

Iron-catalyzed lipid peroxidation

Membrane and cellular injury

Stellate cells

Activation of collagen production

Progressive hepatic fibrosis

DNA injury

ROS and iron-associated damage

Contribution to carcinogenesis

Slide 17 · How iron overload produces fibrosis

Chronic hepatocellular iron

Oxidative injury

Stellate-cell activation

Collagen deposition and cirrhosis

Iron is directly hepatotoxic; Marked inflammation is not a defining early feature.

Slide 18 · The liver changes with disease duration

Early

Enlarged, dense, brown liver

Progressive

Hepatocyte iron spreads across lobule

Advanced

Septal fibrosis → shrunken cirrhotic liver

These changes reflect cumulative tissue burden, not a rigid staging criterion.

Slide 19 · Hemochromatosis: Periportal iron first

Periportal region → toward central lobule

Morphologic principle

Schematic: Periportal hepatocytes develop cytoplasmic hemosiderin before widespread lobular deposition.

Schematic — not a specimen

Slide 20 · Prussian blue reveals iron deposition

Hemosiderin appears as golden-brown granules with routine microscopy.

Prussian blue produces a blue reaction in iron-containing deposits.

Early parenchymal deposition is prominent in periportal hepatocytes.

Later deposits extend to bile duct epithelium and Kupffer cells.

Slide 21 · Distribution changes as iron burden rises

Stage of loading

Periportal hepatocytes

Greater burden

Other hepatocytes and lobule

Extensive loading

Bile ducts and Kupffer cells

Illustrative progression of deposition distribution, not a validated histologic staging scale.

Slide 22 · The pancreatic lesion explains diabetes

Microscopic response

Iron-related acinar / endocrine damage

Progressive parenchymal atrophy

Interstitial fibrosis

Clinical consequence

Disrupted glucose homeostasis

Diabetes may emerge late

Other metabolic disorders may coexist

Slide 23 · Cardiac, endocrine and joint effects

Organ system

Pathology or physiology

Clinical correlate

Heart

Myocardial hemosiderosis and fibrosis

Arrhythmia / cardiomyopathy

Pituitary–gonadal axis

Pituitary involvement; low gonadotropins

Hypogonadism

Joints

Synovial iron and CPP crystal disease

Arthritis / pseudogout

Skin

Increased melanin, with iron pigmentation

Slate-gray coloration

Slide 24 · Recognizing symptomatic hemochromatosis

Hepatomegaly, abdominal pain and chronic liver disease.

Skin darkening, particularly in sun-exposed regions.

Diabetes or abnormal glucose regulation.

Cardiomyopathy, arrhythmia, arthropathy, or hypogonadism.

The complete classical combination is a late manifestation.

Slide 25 · Diagnosis begins before cirrhosis

Suspicion of excess iron

Serum iron assessment

Causal genetic evaluation

Exclude secondary causes / assess fibrosis

Genetic testing and imaging reduce the need for routine quantitative liver biopsy.

Slide 26 · Secondary iron overload: The differential

Repeated red-cell transfusion may cause systemic hemosiderosis.

Ineffective erythropoiesis can also increase intestinal iron uptake.

Thalassemia and myelodysplastic syndromes are key examples.

Other chronic liver diseases can lower hepcidin production.

Transfusion and marrow-disease history guide the differential.

Slide 27 · Phlebotomy alters the natural history

Treatment principle

Regular phlebotomy removes total-body iron

Can prevent progressive organ injury

Best before irreversible damage

Persistent risk

Advanced cirrhosis may already exist

HCC risk is not fully eliminated

Family screening identifies silent disease

Slide 28 · Hemochromatosis: Clinical exercise

An adult with diabetes, arthropathy, darkened skin and hepatomegaly has elevated iron indices.

Discussion prompts

Which common regulatory axis should be considered?

Why can cirrhosis occur without prominent inflammation?

What acquired causes should be excluded?

Slide 29 · Wilson disease: Inherited copper toxicity

Autosomal recessive loss of ATP7B transporter function.

Impaired biliary copper excretion causes hepatic accumulation.

Copper incorporation into ceruloplasmin is also impaired.

Liver, brain and eye are prominent injured organs.

Slide 30 · Normal copper enters and exits the liver

Dietary copper absorbed

Copper reaches hepatocytes

ATP7B packages and handles copper

Surplus copper leaves in bile

Ceruloplasmin synthesis and biliary disposal are linked to ATP7B.

Slide 31 · ATP7B has two critical functions

Copper handling in Golgi

Copper incorporation into apoceruloplasmin

Formation and secretion of ceruloplasmin

Copper elimination

Movement toward biliary excretion

Protection from toxic intracellular copper

Slide 32 · ATP7B failure creates a double defect

Retained hepatic copper

Biliary clearance is reduced

Hepatocellular copper increases

Cell injury releases copper to blood

Reduced ceruloplasmin

Less copper is loaded onto apoprotein

Measured total serum copper may be low

Unbound copper can still be harmful

Slide 33 · Three molecular routes of copper toxicity

Reactive radicals

Copper catalyzes oxidant chemistry

Membrane and protein damage

Protein interactions

Copper binds protein sulfhydryl groups

Loss of function / stress

Metalloenzymes

Copper displaces physiologic metals

Enzyme dysfunction

Slide 34 · Copper moves beyond the liver

COPPER RETENTION

Liver

Hepatitis / cirrhosis

Basal ganglia

Movement disorder

Cornea

Kayser–Fleischer rings

Erythrocytes

Hemolysis

Slide 35 · Wilson disease has a broad liver phenotype

Milder injury

Steatosis or focal necrosis

Hepatitic injury

Acute or chronic hepatitis

Advanced injury

Progressive fibrosis and cirrhosis

Illustrative spectrum—not an obligatory progression for every patient.

Slide 36 · Why Wilson disease mimics steatohepatitis

Hepatocytes may show fatty change and ballooning.

Mallory hyaline can accompany the injury pattern.

Perisinusoidal fibrosis may be present.

Portal inflammation and necrosis can imitate chronic hepatitis.

Histology alone is not a reliable etiologic label.

Slide 37 · Acute Wilson hepatitis can look infectious

Morphologic overlap

Acute hepatocellular injury

Focal or severe necrosis

Inflammatory changes

Diagnostic implication

Age and family history help

Copper studies are necessary

Do not infer a viral cause from biopsy alone

Slide 38 · Copper staining cannot confirm Wilson disease

Hepatic injury may resemble several other liver disorders.

Histochemical copper staining lacks adequate sensitivity.

The stain is also not specific for Wilson disease.

Clinical, biochemical and molecular evidence must be integrated.

Slide 39 · Neurologic Wilson disease localizes to basal ganglia

Tremor, incoordination, chorea or choreoathetosis.

Rigid or spastic dystonia may develop.

Masklike facies, gait changes and rigidity are described.

Psychiatric manifestations may coexist with hepatic disease.

Slide 40 · Kayser–Fleischer rings: Tissue localization

Limbal copper ring

Morphologic principle

Schematic: Copper deposits in Descemet membrane near the corneal limbus.

Schematic — not a specimen

Slide 41 · Copper can cause hemolytic anemia

Hepatocyte copper leakage

Circulating reactive copper

Erythrocyte oxidant injury

Hemolytic anemia

The hemolytic component may accompany otherwise diverse hepatic presentations.

Slide 42 · Wilson disease: Diagnostic evidence

Test / finding

Source-described role

Limitation or interpretation

Serum ceruloplasmin

Often reduced

May be normal in liver injury

Hepatic copper

Increased; highly informative

Biopsy and sampling considerations

Urinary copper

Increased excretion

Must be interpreted clinically

ATP7B sequencing

Molecular support

Variants differ in pathogenicity

Slit-lamp assessment

Kayser–Fleischer rings

Not every hepatic case has rings

Slide 43 · Interpreting copper tests requires context

Reduced ceruloplasmin is helpful but not infallible.

Total serum copper can be low despite tissue overload.

Hepatic copper and urinary copper reflect different compartments.

ATP7B sequencing can clarify ambiguous biochemical findings.

A single nonspecific histologic pattern should not overrule the workup.

Slide 44 · Wilson disease is treatable

Reduce circulating / tissue copper

D-Penicillamine or trientine chelation

Zinc-based treatment limits intestinal uptake

Advanced liver damage

Liver transplantation for severe disease

Transplant can correct hepatic metabolic defect

Slide 45 · Wilson disease: Clinical exercise

A teenager has abnormal liver tests, tremor and mood changes; The corneal examination reveals a pigmented peripheral ring.

Discussion prompts

Which transporter is implicated?

Why might total serum copper be low?

Which testing domains support diagnosis?

Slide 46 · α1-Antitrypsin deficiency: Liver and lung

Inherited deficiency of a circulating serine protease inhibitor.

Loss of anti-elastase protection promotes pulmonary emphysema.

Misfolded α1-antitrypsin accumulates in hepatocyte ER.

Liver injury reflects a toxic gain of function within secretory cells.

Slide 47 · Pi genotype identifies α1-antitrypsin variants

Genotype / allele

Expected phenotype from source

Clinical interpretation

PiMM

Common wild-type genotype

Normal secreted inhibitor

PiZZ

Markedly diminished serum α1-antitrypsin

High risk of liver and lung disease

PiMZ

Intermediate α1-antitrypsin levels

Incomplete / variable manifestations

Slide 48 · PiZZ: Low plasma level, retained hepatocyte protein

Systemic circulation

PiZZ levels ≈10% of normal

Reduced inhibition of neutrophil proteases

Hepatocyte

Mutant protein misfolds and aggregates

Accumulation occurs in endoplasmic reticulum

Slide 49 · Normal α1-antitrypsin secretion

Protein synthesized in hepatocyte

Folding within ER

Trafficking through Golgi

Release into blood

Normal secretory trafficking supplies antiprotease protection to tissues.

Slide 50 · PiZ misfolding blocks secretory trafficking

PiZ variant polypeptide

Abnormal folding and aggregation

Retention inside hepatocyte ER

Proteotoxic stress and injury

The retained protein is toxic even though circulating protein is deficient.

Slide 51 · Why this is gain-of-function and loss-of-function

Liver: Toxic gain of function

Aggregated mutant protein retained

ER stress and unfolded protein response

Hepatocellular injury

Lung: Loss of function

Depleted circulating antiprotease

Neutrophil elastase remains active

Parenchymal destruction → emphysema

Slide 52 · ER stress links aggregation to injury

α1AT-Z accumulates

Unfolded protein response

Cellular stress signaling

Apoptosis may occur

Source describes a pathway that may culminate in hepatocyte apoptosis.

Slide 53 · Why PiZZ carriers differ clinically

Intracellular α1AT-Z accumulation occurs in PiZZ individuals.

Only a subset develops overt liver disease.

Additional genetic and environmental modifiers are suspected.

The number of cytoplasmic globules does not reliably grade severity.

Slide 54 · Characteristic α1AT hepatocyte inclusions

Stylized retained protein globules, stronger periportally

Morphologic principle

Schematic: Rounded cytoplasmic inclusions in hepatocytes; Not a genuine PAS-D photomicrograph.

Schematic — not a specimen

Slide 55 · PAS with diastase highlights the globules

Affected hepatocytes contain round-to-oval cytoplasmic inclusions.

Globules are strongly periodic acid–Schiff positive.

They remain after diastase digestion (PAS-D resistant).

This pattern reflects retained misfolded α1-antitrypsin protein.

Slide 56 · Zonal distribution and timing matter

Early / mild

Predominantly periportal globules

Progressive injury

Globules extend toward central hepatocytes

Young infant

Clinical hepatitis may precede visible globules

Absence of globules early in life does not exclude disease.

Slide 57 · Neonatal α1AT liver disease

Can present with hepatitis during infancy.

Severe neonatal presentations may progress rapidly to cirrhosis.

Globules may not yet be visible in the earliest biopsies.

Diagnosis requires integration of phenotype and laboratory findings.

Slide 58 · Adult α1AT liver disease

May appear as chronic hepatitis or progressive hepatic fibrosis.

Cirrhosis is a major late complication.

Hepatocellular carcinoma can occur, often with cirrhosis.

Some individuals remain without overt liver symptoms.

Slide 59 · α1AT deficiency in the lung

Low circulating α1AT

Insufficient protease inhibition

Unopposed neutrophil elastase

Pulmonary emphysema

Pulmonary disease is a consequence of deficient inhibitor activity, not hepatic protein accumulation.

Slide 60 · The hepatic risk is not only cirrhosis

Persistent misfolded protein may produce chronic cellular injury.

Progressive fibrosis can eventually impair hepatic architecture.

The excerpt describes hepatocellular carcinoma in some PiZZ adults.

Liver and pulmonary outcomes must be evaluated separately.

Slide 61 · Liver transplantation corrects the hepatic defect

After hepatic transplantation

Donor hepatocytes synthesize functioning protein

Hepatic protein retention no longer occurs

Hepatic disease may be cured

What it does not reverse

Existing pulmonary damage is not cured

Pulmonary disease requires separate care

Slide 62 · α1AT deficiency: Clinical exercise

A child with chronic liver injury has hepatocytes containing diastase-resistant PAS-positive cytoplasmic globules.

Discussion prompts

Which inherited secretory-protein defect fits best?

What is the mechanism of liver injury?

What extrahepatic disease should be considered?

Slide 63 · The defining hepatic lesion differs

Disorder

Principal hepatocyte abnormality

Useful morphological clue

Hemochromatosis

Excess iron deposition

Periportal hemosiderin; Prussian blue positive

Wilson disease

Copper-associated hepatocyte injury

Variable hepatitis, steatosis / steatohepatitis

α1AT deficiency

ER retention of aberrant protein

PAS-D–resistant globules in hepatocytes

Slide 64 · Age and clinical presentation are discriminators

Hemochromatosis

Wilson disease

α1AT deficiency

Usually adult onset after decades of loading

Often childhood to young-adult presentation

Can present in infancy or adulthood

Diabetes, pigmentation, arthropathy

Hepatitis, neurologic signs, corneal rings

Chronic liver disease with lung emphysema

Iron accumulation and secondary causes

Biochemical / genetic copper evaluation

Protein phenotype / deficiency and PAS-D inclusions

Slide 65 · Tests interrogate different disease biology

Iron physiology

Serum iron indices; Causative genotype

Biopsy or imaging for consequences

Copper handling

Ceruloplasmin, urinary / hepatic copper

ATP7B and ocular examination

α1AT secretion

Circulating α1AT level and Pi phenotype

Biopsy inclusion pattern is supportive

Slide 66 · A phenotype-first clinical approach

Identify hepatic syndrome

Seek extrahepatic clues

Choose metal / protein testing

Integrate genetics with pathology

Morphology is informative but rarely replaces clinical and biochemical context.

Slide 67 · Shared outcome; Distinct mechanisms

Iron

Overdelivery + oxidant stress

Cirrhosis; HCC risk

Copper

Transport failure + copper toxicity

Hepatitis; Neural injury

α1AT

Proteotoxic ER retention

Chronic liver injury; Emphysema

Slide 68 · Integration exercise: Choose the disorder

Three teaching vignettes: (A) adult iron overload with diabetes; (B) adolescent hepatitis with tremor; (C) infant hepatitis with PAS-D hepatocyte inclusions.

Discussion prompts

Assign one inherited liver disease to each vignette.

Name the causal molecular pathway for each.

Identify one potentially informative investigation.

Slide 69 · Core distinctions to retain

Hemochromatosis: Hepcidin–ferroportin dysfunction → excess iron entry.

Wilson disease: Defective ATP7B → reduced copper clearance and ceruloplasmin loading.

α1AT deficiency: Mutant protein is retained in ER while circulating inhibitor falls.

Diagnostic morphology differs: Iron stain, nonspecific copper injury, PAS-D globules.

Earlier diagnosis can prevent or limit irreversible organ damage.

Slide 70 · Primary reference

Robbins, Cotran & Kumar: Pathologic Basis of Disease

11th edition (2026)

Inherited Liver Disease: Hemochromatosis, Wilson Disease, α1-Antitrypsin Deficiency