Inborn Errors of Metabolism 1) Phenylketonuria 2) Alkaptonuria

1. INBORN ERRORS OF
METABOLISM
Phenylketonuria
Alkaptonuria
H.KALIMANI
I - M.SC., ZOOLOGY
HAJEE KARUTHA ROWTHER
HOWDIA COLLEGE
UTHAMAPALAYAM

2. INBORN ERRORS OFMETABOLISM
Form large class of genetic diseases
involving congenital disorders of metabolism.
The majority are due to the defects of single
genes that code for enzymes that facilitate
conversion of various substances into others.
In most of the disorders, problems arise due
to accumulation of substances which are toxic
or interfere with normal function or to the

3. effects of reduced ability to synthesize essential
compounds.
Inborn errors of metabolism are now often
referred to as congenital metabolic diseases or
inherited metabolic disorders.
The term inborn errors of metabolism was
coined by a British physician Archibald Garrod in
1908.

5. PHENYLKETONURIA
Phenylketonuria (commonly known as PKU)
is an inherited disorder that increases the levels
of a substances callled phenylalanine in the
blood & cerebrospinal fluid.
Phenylalanine is a building block of proteins
that is obtained through the diet.

6. If PKU is not treated, phenylalanine can build
up to harmful levels in the body, causing
intellectual disability and other serious health
problems.
Other name for this condition folling disease.

7. SIGNS & SYMPTOMS
PKU vary from mild to severe. The most
severe form of this disorder is known as classic
PKU.
Permanent intellectual disability
Seizures
Delayed development
Behavioral problems
Psychiatric disorders (ADHD/ADD, autism,
anxiety, depression, etc)

8. Untreated individuals may have a musty or
mouse-like odor (excess phenylalanine in the body)
Lighter skin and hair colour and also have
eczema.
Other characteristic medical problems include
heart defects or other heart problems, an
abnormally small head size (microcephaly).

9. Children suffering with this disease
phenylpyruvic idiots

10. FREQUENCY
The occurrence of PKU varies among ethnic
groups and geographic regions worldwide.
In the United States, PKU occurs in 10,000
to 15,000 newborns.
Severe signs and symptoms of classic PKU
are rarely seen.

11. GENETICS & INHERITANCE PATTERN &
PATHOPHYSIOLOGY

12. DIAGNOSIS & TREATMENT
Newborn screening ( blood taken from heel
of the juvenile or newborn after birth)
MEDICATION:
Sapropterin (kuvan)  helps to decrease the
phenylalanine level in the blood.
Excess phenylalanine is excreted by urine.
This is controlled by phenylalanine free diet.

13. ALKAPTONURIA
Alkaptonuria is a rare genetic metabolic
(organic acid) disorder characterized by the
accumulation of homogentisic acid in the body.
Affected individual lack enough functional
level of an enzyme required to breakdown
homogentisic acid.

14. SIGNS & SYMPTOMS
Ochronosis a build up of dark pigment in
connective tissues such as cartilage and skin,
is also characteristic of the disorder.
This blue-black pigmentation usually
appears after age 30.
People with alkaptonuria typically develop
arthritis, particularly in the spine and large
joints, beginning in early adulthood.

15. Other features of this condition can include
heart problems, kidney stones and prostate stone.
Dark spots in the sclera, thickened and darkened
cartilage in your ears.
Urine to turn black when exposed to air.

17. FREQUENCY
This condition is rare, affecting 1 in
2,50,000 to 1 million people worldwide.
Alkaptonuria is more common in certain
area of slovakia & dominican republic.

18. GENETICS & INHERITANCE PATTERN &
PATHOPHYSIOLOGY
AUTOSOMAL
RECESSIVE
PATTERN

19. PATHOPHYSIOLOGY
PATHOPHYSIOLOGY

20. DIAGNOSIS & TREATMENT
Gas chromatography trace the
homogentisic acid in urine.
Molecular genetic testing to check
mutated gene.
MEDICATION:
There is no particular treatment but doctor
recommend ascorbic acid & vitamin C, low
protein diet.

21. THANK YOU