Non-alcoholic fatty liver disease (NAFLD) is the buildup of fat in the liver not caused by alcohol. It is the most common form of chronic liver disease, affecting 10-20% of children globally. Risk factors include obesity, diabetes, and metabolic syndrome. NAFLD can progress from a harmless fat buildup (steatosis) to a serious inflammation (NASH), and eventually fibrosis and cirrhosis if not addressed. The pathogenesis involves genetic predisposition combined with environmental factors like diet, gut bacteria, and insulin resistance that together cause liver damage over time.

1. Non-alcoholic Fatty Liver Disease
in Children
• Dr CSN Vittal

2. Non-Alcoholic Fatty Liver Disease (NAFLD)
• Non-alcoholic fatty liver disease (NAFLD) is the build up of extra fat in
liver cells that is not caused by alcohol.
• If more than 5% – 10% percent of the liver’s weight is fat, then it is
called a fatty liver (steatosis).
• American liver foundation

3. Non-Alcoholic Fatty Liver Disease (NAFLD)
• Most prevalent form of chronic liver disease, affecting 10%–20% of the general paediatric
population.
• Within the next 10 years it is expected to become the leading cause of liver pathology, liver failure
and indication for liver transplantation in childhood and adolescence in the Western world.
• 90% of those undergoing bariatric surgery have NAFLD
• Prevalence of childhood NAFLD globally is in the range of 9 to 37%
• Prevalence of NAFLD in normal-weight children and overweight/obese children is reported to range
about 3-10% and 8-80%, respectively
• Prevalence of fatty liver in the general adult population of India is in the range of 5% to 28%, with
higher prevalence among the overweight and diabetics
• Prevalence of NAFLD in normal-weight children and overweight/obese children is reported to range
about 3-10% and 8-80%, respectively

4. Non-Alcoholic Fatty Liver Disease - Stages
1. Simple fatty liver (steatosis) – a largely harmless build-up of fat in the liver cells that
may only be diagnosed during tests carried out for another reason
2. Non-alcoholic steatohepatitis (NASH) – a more serious form of NAFLD, where the
liver has become inflamed; (this is estimated to affect up to 5% of the UK population)
3. Fibrosis – persistent inflammation causes scar tissue around the liver and
nearby blood vessels, but the liver is still able to function normally
4. Cirrhosis – the most severe stage, occurring after years of inflammation, where the
liver shrinks and becomes scarred and lumpy; this damage is permanent and can lead
to liver failure and liver cancer
• https://www.nhs.uk/conditions/non-alcoholic-fatty-liver-disease/

7. NASH
• Hepatic steatosis
• Active hepatocyte
inflammation in the form
of ballooning
degeneration
• Risk of fibrosis and
progression to
cirrhosisHCC
• Requires a liver biopsy for
diagnosis
Ballooning degeneration:
--Form of cell death (apoptosis).
--Name derived from the fact that the cells undergoing this
form of cell death increase in size or “balloon”
--Descriptive term used in the context of steatohepatitis
Mallory bodies are damaged intermediate filaments within
the hepatocytes.

8. What populations are at higher
risk for NAFLD?
• Major components of the
metabolic syndrome.
• The presence of at least three of
these components define the
presence of metabolic syndrome.
• Drug Metab Rev. 2017 May; 49(2): 197–211.

9. What populations are at higher
risk for NAFLD?
•Risk Factors
• Obesity, (↑ risk with advancing BMI and waist circumference)
• Impaired fasting glucose
• Hispanic heritage
• Male gender
• Advancing age
• Coined the “Hepatic Manifestation” of Metabolic syndrome
• Those with the PNPLA3 genotype MM have an increased
tendency for hepatic fat storage

10. Clinical Presentation
• The mean age of diagnosis is 11–13 years old
• A dull or aching pain in the top right hypochondrium
• extreme tiredness
• unexplained weight loss
• Weakness
• liver might be slightly enlarged and
• acanthosis nigricans - commonly over the neck and the under arm area.
• If cirrhosis develops,
• jaundice
• itchy skin, and
• oedema
• NAFLD-associated comorbidities, including insulin resistance and Type II
Diabetes Mellitus,

11. Clinical Indicators
• The presence of any of the following, especially with a history of
abnormal AST/ALT, should lead to a work
— Presence of obesity, especially morbid obesity (BMI > 35)
— Diagnosis of type 2 diabetes mellitus
— Diagnosis of metabolic syndrome
— History of obstructive sleep apnea
— Presence of insulin resistance
— Chronic elevation of AST/ALT, otherwise unexplained

12. NAFLD - Pathogenesis
• A complex interaction among environmental factors (i.e., Western
diet), obesity, changes in microbiota, and predisposing genetic
variants resulting in a disturbed lipid homeostasis and an excessive
accumulation of triglycerides and other lipid species in
hepatocytes. Insulin resistance is a central mechanism that leads to
lipotoxicity, endoplasmic reticulum stress, disturbed autophagy,
and, ultimately, hepatocyte injury and death that triggers hepatic
inflammation, hepatic stellate cell activation, and progressive
fibrogenesis, thus driving disease progression.

13. NAFLD - Pathogenesis
• Two hit Hypothesis : (now obsolete)
• Leptin may stimulate inflammation, fat storage
• Adiponectin is anti-inflammatory, anti-steatotic
• Multi hit Hypothesis
• Multiple insult acting together on genetically
predisposed subjects.

14. Normal Liver NASHNAFL
“Simple Steatosis”
Cirrhosis
Clin Med (Lond). 2015 Apr
• Sedentary lifestyle
• High fat diet
• Insulin resistance
• Obesity
• Oxidative Stress
• Mitochondrial Dysfunction
• Inflammatory Cytokines
• Gut Dysbiosis, Endotoxins
1 2
“Two Hit” Hypothesis

15. “Multi-hit” Hypothesis
• Multiple insults acting together on genetically predisposed patient
(insulin resistance, altered gut bacteria, inflammatory cytokines..etc)
• Not necessarily a linear progression from simple steatosis to NASH
• Currently most accepted understanding of NAFLD

16. • Multiple insults acting together on genetically predisposed patient
(insulin resistance, altered gut bacteria, inflammatory cytokines..etc)
• Not necessarily a linear progression from simple steatosis to NASH
• Currently most accepted understanding of NAFLD
“Multi-hit” Hypothesis

17. 1. Adipose tissue inflammation
2. De novo Lipogensis (DNL)
3. Insulin Resistance
4. Lipotoxicity
5. Mitochondrial Dysfuntion
6. Oxidative Stress
7. Endoplasmic Reticulum Stress
8. Microbiota Associated Mechanism
9. Short-Chain Fatty Acids (SCFAs) Relevant
Mechanism
10. Dietary Choline Mechanism
11. Bile Acid Pool Related Mechanism
12. Endogenous Alcohol Theory
13. Intestinal Permeability and Endotoxemia
14. Saturated Fatty Acids
15. Fructose
16. Genetics
17. PNPLA3 ( Patatin-Like Phosopholipase Domain
Containing 3)
18. TM6SF2 (Transmembrane 6 Superfamily Member 2)
Interplay between Diet, Microbiota, and Host Genetics
• Gastroenterology Research and Practice Volume 2016, Article ID 2862173, 13 pages
“Multi-hit” Hypothesis

18. 1. Adipose tissue inflammation
• H. Tilg, “The role of cytokines in non-alcoholic fatty liver disease,” Digestive Diseases, vol. 28, no. 1, pp. 179–185, 2010.
• C. M. Hasenour, E. D. Berglund, and D. H. Wasserman, “Emerging role of AMP-activated protein kinase in endocrine control of metabolism in the liver,” Molecular and
Cellular Endocrinology, vol. 366, no. 2, pp. 152–162, 2013
• Adipocytes under inflammation secrete cytokines and chemokines, particularly tumor
necrosis factor-α (TNF-α), interleukin-6 (IL-6), and CC-chemokine ligand-2 (CCL2)
• Adipose tissue-derived TNF-α and IL-6 have been shown to regulate hepatic insulin
resistance via upregulation of SOCS3, a suppressor of cytokine signalling
• CCL2 recruits macrophages to the adipose tissue, resulting in even more local cytokine
production and perpetuating the inflammatory cycle;
• TNF-α and IL-6 induce a state of insulin resistance in adipocytes, which stimulates
triglyceride lipolysis and fatty acid release into the circulation.
• extrahepatic adipocytes are compromised in their natural ability to secrete adiponectin, an
anti-inflammatory adipokine that facilitates the normal partitioning of lipid to adipocytes for
storage
• Together, these abnormalities accentuate fat loss from adipocytes and promote ectopic fat
accumulation.

19. 2. de novo Lipogensis (DNL)
• J. E. Lambert, M. A. Ramos-Roman, J. D. Browning, and E. J. Parks, “Increased de novo lipogenesis is a distinct
characteristic of individuals with nonalcoholic fatty liver disease,” Gastroenterology, vol. 146, no. 3, pp. 726–735,
2014.
• A 3-fold higher rate of de novo fatty acid synthesis is seen in these
subjects.
• fructose is a more potent inducer of DNL than glucose
• dietary fat, particularly saturated fat, stimulates DNL by upregulating
SREBP-1 (sterol responsive element binding protein), a key regulator
of the lipogenic genes in the liver

20. 3. Insulin Resistance
• M. Gaggini, M. Morelli, E. Buzzigoli, R. A. DeFronzo, E. Bugianesi, and A. Gastaldelli, “Non-alcoholic fatty liver
disease (NAFLD) and its connection with insulin resistance, dyslipidemia, atherosclerosis and coronary heart
disease,” Nutrients, vol. 5, no. 5, pp. 1544–1560, 2013.
• Serine phosphorylation of insulin receptor substrates by inflammatory
signal transducers such as c-jun N-terminal protein kinase 1 (JNK1) or
inhibitor of nuclear factor-κB kinase-β(IKK-β) is considered one of the key
aspects that disrupts insulin signalling
• Insulin resistance is characterized not only by increased circulating insulin
levels but also by increased hepatic gluconeogenesis, impaired glucose
uptake by muscle, and increased release of free fatty acids and
inflammatory cytokines from peripheral adipose tissues, which are the key
factors promoting accumulation of liver fat and progression of hepatic
steatosis

21. 4. Lipotoxicity
• T. Sharifnia, J. Antoun, T. G. C. Verriere et al., “Hepatic TLR4 signaling in obese NAFLD,” American Journal of
Physiology—Gastrointestinal and Liver Physiology, vol. 309, no. 4, pp. G270–G278, 2015
• Lipids, including Free cholesterol (FC), long chain saturated fatty acids (SFA), and
certain lipid intermediates from excessive SFA, can activate a variety of
intracellular responses such as JNK1 and a mitochondrial death pathway, resulting
in lipotoxic stress in the endoplasmic reticulum and mitochondria, respectively.
• The toll-like receptor 4 (TLR4) is a pattern recognition receptor that activates a
proinflammatory signalling pathway in response to excessive SFAs.
• This pathway is initiated by recruiting adaptor molecules such as toll/IL-1
receptor domain containing adaptor protein (TIRAP) and myeloid differentiation
factor 88 (MyD88) that ultimately lead to activation of nuclear factor κB with
production of TNF-α

22. 5. Mitochondrial Dysfunction
• C. P. Day, “Pathogenesis of steatohepatitis,” Best Practice & Research Clinical Gastroenterology, vol. 16, no. 5,
pp. 663–678, 2002.
• Reduced enzymatic activities of mitochondrial electron transport
chain (ETC) complexes may be attributed to increased generation of
reactive oxygen species (ROS) as a result of ETC leakage during
mitochondrial β-oxidation in energy production (in the form of ATP)

23. 6. Oxidative Stress
• D. Pessayre, “Role of mitochondria in non-alcoholic fatty liver disease,” Journal of Gastroenterology and
Hepatology, vol. 22, supplement 1, pp. S20–S27, 2007
• Recent studies support the idea that oxidative stress may be a
primary cause of liver fat accumulation and subsequent liver injury
• ROS-induced expression of Fas-ligand on hepatocytes may induce
fratricidal cell death.
• These species can initiate lipid peroxidation by targeting
polyunsaturated fatty acids (PUFAs), resulting in the formation of
highly reactive aldehyde products, such as 4-hydroxy-2-nonenal (4-
HNE) and malondialdehyde (MDA)

24. 7. Endoplasmic Reticulum (ER) Stress
• D. Ron and P. Walter, “Signal integration in the endoplasmic reticulum unfolded protein response,” Nature
Reviews Molecular Cell Biology, vol. 8, no. 7, pp. 519–529, 2007
• Under pathological and/or stressful conditions such as NASH, it has been observed that
ER efficiency in the protein-folding, repairing, and/or trafficking machinery is decreased
while the demand of protein synthesis and folding/repair is increased.
• This type of cellular stress usually triggers an adaptive response, aimed at resolving ER
stress, called unfolded protein response (UPR)
• The UPR is mediated by at least three different stress-sensing pathways:
- protein kinase RNA-like ER kinase (PERK),
- inositol-requiring protein 1α (IRE1α), and
- activating transcription factor 6 (ATF6)

25. 8. Microbiota Associated Mechanism
• P. Lin, J. Lu, Y. Wang et al., “Naturally occurring stilbenoid TSG reverses non-alcoholic fatty liver diseases via gut-
liver axis,” PLoS ONE, vol. 10, no. 10, Article ID e0140346, 2015
• Gut microbiota may contribute to the pathogenesis of NAFLD through
several mechanisms
1. Increased production and absorption of gut short-chain fatty acids;
2. Altered dietary choline metabolism by the microbiota;
3. Altered bile acid pools by the microbiota;
4. Increased delivery of microbiota-derived ethanol to liver;
5. Gut permeability alterations and release of endotoxin; and
6. Interaction between specific diet and microbiota.

26. 9. Short-Chain Fatty Acids (SCFAs)
Relevant Mechanisms
• P. Lin, J. Lu, Y. Wang et al., “Naturally occurring stilbenoid TSG reverses non-alcoholic fatty liver diseases via gut-
liver axis,” PLoS ONE, vol. 10, no. 10, Article ID e0140346, 2015
• As an energy precursor, SCFAs are implicated in the pathogenesis of NAFLD
because of their possible contribution to obesity. BUT ???
• Beneficial effects of SCFAs
• immunoregulation, enhanced intestinal barrier function,
• acting as a histone deacetylase 1 (HDAC) inhibitor to decrease expression of lipogenic
genes and to increase carnitine palmitoyltransferase 1A expression , and
• a peroxisome proliferator-activated receptor-γ- (PPARγ-) dependent mechanism,
shifting metabolism in adipose and liver tissue from lipogenesis to fatty acid oxidation

27. 10. Dietary Choline Mechanism
• M. D. Spencer, T. J. Hamp, R. W. Reid, L. M. Fischer, S. H. Zeisel, and A. A. Fodor, “Association between
composition of the human gastrointestinal microbiome and development of fatty liver with choline
deficiency,” Gastroenterology, vol. 140, no. 3, pp. 976–986, 2011
• Dietary choline-deficiency has been linked with a variety of conditions
including hepatic steatosis.
• Choline has role in fat export out of the hepatocytes
• Choline-depleted diet revealed that increased Gammaproteobacteria
abundance and decreased Erysipelotrichi abundance were protective
against developing steatosis

28. 11. Bile Acid Pool Related Mechanisms
• R. H. McMahan, X. X. Wang, L. L. Cheng et al., “Bile acid receptor activation modulates hepatic monocyte
activity and improves nonalcoholic fatty liver disease,” The Journal of Biological Chemistry, vol. 288, no. 17, pp.
11761–11770, 2013
• Bile acids have also been recognized as important
cell signaling molecules regulating lipid
metabolism, carbohydrate metabolism, and
inflammatory response

29. 12. Endogenous Alcohol Theory
• I. C. de Medeiros and J. G. de Lima, “Is nonalcoholic fatty liver disease an endogenous alcoholic fatty liver
disease?—a mechanistic hypothesis,” Medical Hypotheses, vol. 85, no. 2, pp. 148–152, 2015.
• The composition of NASH microbiomes was found to be distinct from those
of healthy and obese microbiomes, and Escherichia stood out as the only
abundant genus that differed between NASH and obese patients.
Because Escherichia are ethanol producers, this finding is in agreement
with their previous report that alcohol-metabolizing enzymes are
upregulated in NASH livers
• Alcohol theory currently faces conflicting results from different
investigators.

30. 13. Intestinal Permeability and
Endotoxemia
• R. Medzhitov, “Toll-like receptors and innate immunity,” Nature Reviews Immunology, vol. 1, no. 2, pp. 135–145,
2001.
• Changes in the composition of microbiota can lead to increased intestinal
permeability and subsequent overflow of harmful bacterial by-products to
the liver that in turn triggers hepatic inflammation and metabolic
disorders.
• Endotoxin, that is, lipopolysaccharide (LPS), is derived from Gram-negative
bacteria, and it has long been implicated in chronic liver diseases
• LPS and other exogenous stimuli are responded to first by innate immunity
through pattern recognition receptors such as toll-like receptors (TLRs) and
NOD-like receptors (NLRs)

31. 14. Saturated Fatty Acids
• D. Wang, Y. Wei, and M. J. Pagliassotti, “Saturated fatty acids promote endoplasmic reticulum stress and liver
injury in rats with hepatic steatosis,” Endocrinology, vol. 147, no. 2, pp. 943–951, 2006.
• In liver and hepatocytes not exposed to alcohol, SFAs appear to promote
apoptosis and liver injury
• SFAs increase the saturation of membrane phospholipids, thus initiating unfolded
protein response (UPR) and leading to ER stress
• SFAs also affect mitochondrial metabolism and promote ROS accumulation
• SFAs can interact with gut microbiota to affect the progression of liver injury
• Overflow of SFAs to the distal intestine reduced microbial diversity and increased
the Firmicutes-to-Bacteroidetes ratio in the intestine

32. 15. Fructose
• M. F. Abdelmalek, A. Suzuki, C. Guy et al., “Increased fructose consumption is associated with fibrosis severity in
patients with nonalcoholic fatty liver disease,” Hepatology, vol. 51, no. 6, pp. 1961–1971, 2010.
• Excess fructose consumption is involved in the pathogenesis of NAFLD and
that upregulated de novo lipogenesis and inhibited fatty acid β-oxidation
are distinct metabolic processes for the development of hepatic steatosis in
individuals with NAFLD
• Increased fructose consumption is associated with a higher fibrosis stage in
patients with NAFLD, independent of age, sex, BMI, and total calorie intake
• Increased expression of TLRs has been implicated in the development of
fructose-induced hepatic steatosis

33. 16. Genetic Background of NAFLD
• F. S. Macaluso, M. Maida, and S. Petta, “Genetic background in nonalcoholic fatty liver disease: a comprehensive
review,” World Journal of Gastroenterology, vol. 21, no. 39, pp. 11088–11111, 2015
• Genetic variation does influence disease risk in NAFLD
• Dozens of genes with multiple polymorphisms have been discovered in
genome-wide association studies (GWAS) that may be responsible for risk
of NAFLD in certain populations

34. 17. PNPLA3 (Patatin-Like Phospholipase Domain
Containing 3)
• M. Krawczyk, P. Portincasa, and F. Lammert, “PNPLA3-associated steatohepatitis: toward a gene-based
classification of fatty liver disease,” Seminars in Liver Disease, vol. 33, no. 4, pp. 369–379, 2013
• PNPLA3 gene (adiponutrin) encodes a transmembrane polypeptide chain exhibiting
triglyceride hydrolase activity which is highly expressed on the endoplasmic reticulum
and lipid membranes of hepatocytes and adipose tissue and in human stellate cells.
• Subpopulations of NAFLD patients with PNLA3 mutation are not associated with insulin
resistance, a hallmark of metabolic syndrome
• A distinct entity might exist in which the PNPLA3 risk allele appears to be a major driver
of disease progression in combination with viral infection, alcohol abuse, lifestyle
(unhealthy diet and inactivity), and/or non-lifestyle (cryptogenic) causes, Eg. PNPLA3-
associated steatohepatitis (“PASH”)

35. 18. TM6SF2 (Transmembrane 6
Super family Member 2)
• G. Musso, M. Cassader, E. Paschetta, and R. Gambino, “TM6SF2 may drive postprandial lipoprotein cholesterol
toxicity away from the vessel walls to the liver in NAFLD,” Journal of Hepatology, vol. 64, no. 4, pp. 979–981, 2016.
• TM6SF2 gene regulated hepatic triglyceride secretion and that the
functional impairment of TM6SF2 promoted NAFLD
• Carriers of the TM6SF2 E167K variant seem to be more at risk for
progressive NASH, but at the same time they could be protected
against cardiovascular diseases

37. TGTG
TG
TG
TG
TG
HSL
Chylomicrons
FFAs
FFAs
B-oxidation
TGs in lipid
dropletes
Cholesterol
Phospholipids VLDL
DNL
Glucose +
Fructose
Peroxisome
HSL : Hormone sensitive lipase
DNL : de novo lipogenesis
FFAs: Free fatty acids
VLDL : Very low density lipoproteins

38. TGTG
TG
TG
TG
TG
HSL
Chylomicrons
FFAs
FFAs
B-oxidation
Lipid droplets in
hepatocytes
Cholesterol
Phospholipids VLDL
DNL
1) Insulin ResistanceInsulin
SREBP-1
IRS-2
FFAs cause
defective
insulin
signaling
M E T A B O L I S M C L I N I C A L A N D E X P E R I M E N T A L 6 5 ( 2 0 1 6 ) 1 0 3 8 – 1 0 4 8
Peroxisome
SREBP-1 : sterol regulatory element-binding protein 1
IRS-2 : insulin receptor substrate 2
FFAs: Free fatty acids
VLDL : Very low density lipoproteins

39. TGTG
TG
TG
TG
TG
HSL
Chylomicrons
FFAs
FFAs
B-oxidation
Lipid droplets in
hepatocytes
Cholesterol
Phospholipids VLDL
DNL
1) Insulin Resistance
2) Mitochondrial
Dysfunction
Insulin
SREBP-1
IRS-2
FFAs cause
defective
insulin
signaling
M E T A B O L I S M C L I N I C A L A N D E X P E R I M E N T A L 6 5 ( 2 0 1 6 ) 1 0 3 8 – 1 0 4 8
Peroxisome
ROS
Ferramosca A et al . Antioxidants and fatty liver
INFLAMMATION
FIBROSIS
APOPTOSIS
Stellate cells
ROS : Reactive oxygen species
TG : Triglycerides
FFAs : Free fatty acids
SREBP-1 : sterol regulatory element-binding protein 1
IRS-2 : insulin receptor substrate 2

40. TGTG
TG
TG
TG
TG
HSL
Chylomicrons
FFAs
FFAs
B-oxidation
Lipid droplets in
hepatocytes
Cholesterol
Phospholipids VLDL
DNL
1) Insulin Resistance
2) Mitochondrial
Dysfunction
3) ER Stress
Insulin
SREBP-1
IRS-2
FFAs cause
defective
insulin
signaling
M E T A B O L I S M C L I N I C A L A N D E X P E R I M E N T A L 6 5 ( 2 0 1 6 ) 1 0 3 8 – 1 0 4 8
Peroxisome
ROS INFLAMMATION
FIBROSIS
APOPTOSIS
Stellate cells
ER
UPR • Dec protein
synthesis
• Incr Protein
transit and
degredation
JNK INFLAMMATION
APOPTOSIS
Impaired insulin signalingJNK : c-jun terminal kinase
UPR : unfolded protein response
IRS-2 : insulin receptor substrate 2

41. TGTG
TG
TG
TG
TG
HSL
Chylomicrons
FFAs
FFAs
B-oxidation
Lipid droplets in
hepatocytes
Cholesterol
Phospholipids VLDL
DNL
1) Insulin Resistance
2) Mitochondrial
Dysfunction
3) ER Stress
4) Adipose tissue
Dysfunction
Insulin
SREBP-1
IRS-2
FFAs cause
defective
insulin
signaling
M E T A B O L I S M C L I N I C A L A N D E X P E R I M E N T A L 6 5 ( 2 0 1 6 ) 1 0 3 8 – 1 0 4 8
Peroxisome
ROS
Ferramosca A et al . Antioxidants and fatty liver
INFLAMMATION
FIBROSIS
APOPTOSIS
Stellate cells
ER
UPR • Dec protein
synthesis
• Incr Protein
transit and
degradation
JNK INFLAMMATION
APOPTOSIS
Impaired insulin signaling
IL-6
TNF-α
Leptin

42. TGTG
TG
TG
TG
TG
HSL
Chylomicrons
FFAs
FFAs
B-oxidation
Lipid droplets in
hepatocytes
Cholesterol
Phospholipids VLDL
DNL
1) Insulin Resistance
2) Mitochondrial
Dysfunction
3) ER Stress
4) Adipose tissue
Dysfunction
5) Dysbiosis
Insulin
SREBP-1
IRS-2
FFAs cause
defective
insulin
signaling
M E T A B O L I S M C L I N I C A L A N D E X P E R I M E N T A L 6 5 ( 2 0 1 6 ) 1 0 3 8 – 1 0 4 8
Peroxisome
ROS
INFLAMMATION
FIBROSIS
APOPTOSIS
Stellate cells
ER
UPR • Dec protein
synthesis
• Incr Protein
transit and
degradation
JNK INFLAMMATION
APOPTOSIS
Impaired insulin signaling
IL-6
TNF-α
Leptin
LPS
LPS: Lipopolysaccharide

43. TGTG
TG
TG
TG
TG
HSL
Chylomicrons
FFAs
FFAs
B-oxidation
Lipid droplets in
hepatocytes
Cholesterol
Phospholipids VLDL
DNL
1) Insulin Resistance
2) Mitochondrial
Dysfunction
3) ER Stress
4) Adipose tissue
Dysfunction
5) Dysbiosis
6) Inflammatory
State
Insulin
SREBP-1
IRS-2
FFAs cause
defective
insulin
signaling
M E T A B O L I S M C L I N I C A L A N D E X P E R I M E N T A L 6 5 ( 2 0 1 6 ) 1 0 3 8 – 1 0 4 8
Peroxisome
ROS
INFLAMMATION
FIBROSIS
APOPTOSIS
Stellate cells
ER
UPR • Dec protein
synthesis
• Incr Protein
transit and
degradation
JNK INFLAMMATION
APOPTOSIS
Impaired insulin signaling
IL-6
TNF-α
Leptin
LPS
NF-kB
NF-kB : Nuclear factor-jB kinase-b

44. TGTG
TG
TG
TG
TG
HSL
Chylomicrons
FFAs
FFAs
B-oxidation
Lipid droplets in
hepatocytes
Cholesterol
Phospholipids VLDL
DNL
1) Insulin Resistance
2) Mitochondrial
Dysfunction
3) ER Stress
4) Adipose tissue
Dysfunction
5) Dysbiosis
6) Inflammatory
State
Insulin
SREBP-1
IRS-2
FFAs cause
defective
insulin
signaling
M E T A B O L I S M C L I N I C A L A N D E X P E R I M E N T A L 6 5 ( 2 0 1 6 ) 1 0 3 8 – 1 0 4 8
Peroxisome
ROS
INFLAMMATION
FIBROSIS
APOPTOSIS
Stellate cells
ER
UPR • Dec protein
synthesis
• Incr Protein
transit and
degredation
JNK INFLAMMATION
APOPTOSIS
Impaired insulin signaling
IL-6
TNF-α
Leptin
LPS
NF-kB

45. Histology of NASH

46. Extra Hepatic Complications of NAFLD
• 90% of NAFLD patients have at least one feature of the metabolic
syndrome and up to 33% meet the complete diagnosis - metabolic
syndrome
• Cardiovascular Disease
• NAFLD is an independent risk factor for coronary artery disease, as
well as being strongly associated with a number of other
cardiovascular risk factors, including multi-organ insulin resistance,
dyslipidaemia and impaired flow-mediated vasodilatation
• Insulin Resistance and Type II Diabetes Mellitus
• Insulin Resistance (IR) is the most common metabolic abnormality
associated with NAFLD

47. Diagnostic Tools
Maintenance of high index of suspicion
1 Clinical Features
• Over weight /
Obesity
• Hypertension (CV
Disease)
• Insulin Resistance
(Type II DM)
• > 3 years old
• Family h/o.
NAFLD
• Hepatomegaly
• Acanthosis
nigricans
• Transaminases
ALT. AST
• Total Bilirubin
• Proinflammatory
markers
• Cytokines
• Hepatocyte
apoptosis
markers
• Lipid profile (TG,
FFA, Cholesterol)
• Serum
autoantibodies
• Abdominal
ultrasound
• Magnetic
resonance
Imaging
• Transient
Elastography
2 Serum Biomarkers 3 Imaging Techniques 4 Liver Biopsy
• Infammation
• Fibrosis
• Cellunalr
infiltration

48. Diagnosis of NAFLD?
• In 10% of NASH patients, ALT and AST may be normal,
especially with simple steatosis.
• AST/ALT ratio < 1—this ratio is usually > 2 in alcoholic
hepatitis.
• An abnormal ferritin level in the presence of normal
transferrin saturation should always suggest a need to rule
out NASH.

49. U/S Appearance - (NAFLD)
• Hepatic steatosis
• No inflammation
• Can be diagnosed with
imaging alone
• Low risk for disease
progression

50. Radiology - NAFLD?
• Increased echogenicity
• Hepatomegaly
• Low attenuation compared
with the spleen

51. Histopathology - NASH?
• Liver biopsy is the GOLD standard
Do we have to do a biopsy on
EVERYONE with fatty liver
disease??

52. Non-invasive Diagnose of NASH??
• Vibration Controlled Transient
Elastography (Fibroscan) : uses sound
waves to measure the stiffness of liver
tissue.
• MRI Elastography (MRE): to capture
images of shearwave propagation in the
liver producing an elastogram that maps
liver stiffness values with high resolution
• Multiparametric MRI (Liver Multiscan)
• Circulating levels of cytokeratin-18
(CK18)

53. Differential Diagnosis
• Alternate causes of fatty liver:
• Alcohol
• Wilson’s Disease
• Hepatitis C (genotype 3)
• Starvation
• TPN
• Medications (EX: methotrexate, tamoxifen,
corticosteroids)

54. Management of paediatric NAFLD
1st Lifestyle Intervention 2nd Pharmacotherapy 3rd Bariartic Surgery
Diet and Physical exercise
(Education + Intervention)
• Decrease caloric intake
• Decrease fat intake
• Decrease fructose
intake
• Decrease alcohol intake
• Increase physical
exercise
Supplementations:
• Vitamin D
• Omega-3 fatty acids
Insulin sensitisers
• Metformin
• Incretin mimetics
• DDP-4 inhibitors
• Thiazolidinediones
Weight loss:
• Orlistat
Cholesterol regulation:
• Statins
Antiocidants
• Ursodeoxycholic acid
• Vitamin E
Probiotics
• Gastric banding
• Gastric bypass
• Sleeve
gastrectomy
• Intragastric
balloon
Am J Gastroenterol 2012; 107:811–826

55. Management of paediatric NAFLD
CAUSE TREATMENT
Obesity Diet, exercise
Nutritional
deficiencies
Increase vitamins/fiber
Insulin resistance Metformin, pioglitazone
Oxidative stress Antioxidants
Cytokines,
adipokines
Anticytokine therapy
Bacterial
overgrowth
Probiotics/antibiotics
Hyperlipidemia Antihyperlipidemics
Adapted from NEJM 2006;355(22):2361.

56. 1) Review of clinical history
2) RUQ US
3) Full liver enzymes evaluation (rule out viral hepatitis,
autoimmune disease, hemochromatosis, etc
The Lowly fellow’s
algorithm for
elevated LFTS and/or
concern for NAFLD:
1) Imaging assessment of Fibrosis (Fibroscan
or MRE)
2) Review clinical risk
Continue LFT
evaluation as
necessary
Continue liver enzyme
evaluation as necessary
No liver
Biopsy
Liver biopsy
for staging
US(+), no clear alternate
etiologiesUS(-)
Elevated Liver stiffness
Clinically increased riskNormal liver stiffness
Encourage lifestyle modifications
?Vitamin E
Weight loss accountability
Continue to reassess need for staging
(if not already done)
NASH
Non NASH
NAFLD

57. Summary
• What is NAFLD?
• Fat in the liver +/- inflammation and/or fibrosis
• How does NAFLD occur?
• Excess fat, insulin resistance, oxidative damage
• How big of a problem is this?
• HUGE!! 2nd leading cause of liver transplant in the U.S. and climbing.
• What populations are at higher risk?
• Those with obesity, diabetes, HLD, HTN, and of Hispanic heritage
• How can I diagnose NAFLD?
• Imaging. Diagnosing with NASH takes specialized tests.
• How do I manage my patients with NAFLD?
• Lifestyle modifications!! Weight loss is key.

58. • Dr CSN Vittal