GOOD MORNING

BARDET-BIEDL SYNDROME

By:

Dr.Mehul D JaniMaxillofacial surgeon

Case presentation• Name

• Age/sex:18/M• Address:• Case no:• Contact no:+

• Chief complaint: pain in upper front teeth region since last 15 days.

• H/O/P/I: relatively asymptomatic before 15 days. Than he started feeling dull aching continuous pain which gradually increased in frequency and intensity and reached present state.

History:

• No significant family history• Medical history: H/O ratinitis pigmentosa

(since birth),*• Personal history: diet:veg.Bowel/bladder/sleep/appetite: not altered Marital status : unmarried No adverse habits

History:

• Local examination:Non vital tooth:11Pain on percussion:

present irt 11

Radiograph adv: IOPA irt 11,12OCCLUSAL OPG

• Provisional Diagnosis: radicular cyst I.R.T 11.

• Treatment Done: root canal treatment I.R.T 11 followed by apicectomy and enucleation of lesion I.R.T 11.

• On the base of histopathologic examination final diagnosis was granulation tissue irt 11,12.

What Is Special In

This Case ??

partial blindness since birth.(ratinitis pigmentosa)

Postaxial polyductility

High arch plate

Patient has characteristic

features:

Hypogonadism

Mental retardation

Central obesity

Patient has characteristic

features:

Differential diagnosis

ORO

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DIG

ITAL

SYD

ROM

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LAU

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ROM

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BARD

ET-B

IED

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is an autosomal

recessive condition characterised

by rod-cone dystrophy, postaxial polydactyly,central obesity, mental retardation,

hypogonadism, and renal dysfunction.

in which retinal pigmentary

degeneration, mental retardation, and hypogonadism

occur in conjunction with progressive

distal muscle weakness,

but without polydactyly.

for a variety of different genetic disorders that result in malformations of the mouth, teeth, jaw, facial bones, hands, and feet.It has no.of clinical features like……*

On the basis of clinical criterias our patient has:

BARDET-BIEDL syndrome.*

“BARDET-BIEDL syndrome”Introduction

• Bardet-Biedl syndrome (BBS) is an autosomal recessive condition with a wide spectrum of clinical features.

• BBS was first described by Bardet and Biedl in the 1920.• The principal manifestations are

a. rod-cone dystrophy (sometimes called atypical retinitis pigmentosa) ,

b. postaxial polydactyly,c. central obesity,

d. mental retardation, e. hypogonadism, and f. renal dysfunction.*

“BARDET-BIEDL syndrome” Genetics• BBS is genetically

heterogeneous, J Med Genet 1999;36:437–446

with four different location on following genes. BBS1 (11q13), BBS2 (16q22), BBS3 (3p13), and BBS4 (15q21

Düzce Tıp Fakültesi Dergisi 2008; 3:60-63

Linkage analysis studies have so far identified eight distinct loci responsible for the syndrome BBS1(11q13) , BBS2(16q21),BBS3(3p13)-(p12), BBS4(15q22)-(3q23),BBS5(2q31), BBS6( 20p12), BBS7(4q27), BBS8( 14q32).

Diagnostic Criteria&

Clinical Manifestations

• Rod-cone dystrophy• Polydactyly• Obesity • Learning Disabilities• Hypogonadism in male• Renal anomalies

Primary features

Rod – Cone Dystrophy (ratinitis pigmantosa-RP)

• RP is defined as an inherited retinal condition that gradually leads to visual field loss and retinal degeneration.

• RP is not caused by infection, but is an inherited condition.*

• Most commonly X-linked dominant 46% of the cases.

• X- linked recessive inheritance is least common,amounting to 8%.

• Autosomal dominant inheritance isfound in 19% and

• recessive in 19%.

• There are two main cell types within the retina: rods and cones.*

• In RP, the rod cells and eventually the cone cells stop working, causing vision loss.

ROD>CONE

SIGNS AND SYMPTOMS

• Typically include trouble seeing at night ( Nyctalopia) and/or loss of side vision.• In early stages, the quality of vision generally remains

the same, while the field of vision is reduced. This produces “TUNNEL VISION.” As RP progresses, visual clarity, or visual acuity, may also decrease.

• Both eyes are usually affected in a similar way.

TUNNEL VISION*

Testing For Retinitis Pigmentosa

• Visual Acuity Testing :

Testing For Retinitis Pigmentosa

• Visual Field Testing :

Normal Visual Field Retinitis Pigmentosa

Testing For Retinitis Pigmentosa• Electro-retinogram (ERG): This tests rod and cone function,

and is important for confirming a diagnosis of RP.*

Testing For Retinitis Pigmentosa• Fundus photographs — Using a

special camera, doctor can photograph the fundus, or back of the eye. The testing is relatively fast, but requires that the eyes be dilated.

• Optical Coherence Tomography — This test captures cross sectional images of the retina. It measures the thickness of the retina and can identify retinal abnormalities. The device scans the retina surface with light to obtain images.

• Fluorescein Angiogram*

Normal Fundus

R.P Fundus

Associated With Syndrome:

• Usher's Syndrome*• Lawrence-Moon-• Bardet-Biedl Syndrome**• Bassen-Kornzweig disease***• Refsum's disease (Autosomal recessive)****• Kearns-Sayre syndrome*****

Treatment • RP is incurable rather than untreatable.

Patient can always be helped by careful refraction, cataract extraction when indicated, treatment of macular edema *and Vitamin A supplements+.

• Retinal Transplantation’• Retinal prosthesis (ASR)**• sub retinal gene therapy****

Polydactyly • Congenital malformations of

the limbs are among the most frequent congenital anomalies found in humans, and they preferentially affect the distal part, the hand or foot.

• Polydactyly is a Genetic disorder of the seventh chromosome which results in extra fingers or toes. Polydactyly actually means “Extra Digits.”

Polydactyly was discovered by Tyler Steven

Hayden

• There aren’t necessarily symptoms that come with the

disorder other than the obvious extra fingers and toes.

Polydactyly

Post – Axial

Pre-Axial

Central

Forms

Post - axial

Pre - axial

How Is It Inherited?

• Polydactyly can occur by itself as a mutation. It is also a disorder that is passed from parent to child. When it is inherited, it is known as an Autosomal dominant gene. The disorder is located on one of the short legs of chromosome 7.

Statistically Speaking…

Some races and genders are more likely to get Polydactyly than others.

White Male- 3.3/1000 birthsWhite Female- 0.6/1000 birthsBlack Male- 13.5/1000 birthsBlack Female- 11.1/1000

Tests, Cures, and Treatment.

• There are no test to tell you whether or not you are a carrier. If you have the disease, then

you are a carrier. There are no cures for this disorder. The only treatment is surgical

removal.

Hypogonadism • Hypogonadism can be described as diminished functional activity

of the gonads – the testes and ovaries in males and females, respectively – that may result in diminished sex hormone

biosynthesis and impaired gamete production and/or regulation.

• Low androgen (e.g., testosterone) levels are referred to as hypoandrogenism and low estrogen (e.g., estradiol) as

hypoestrogenism, and may occur as symptoms of hypogonadism in both sexes, but are generally only diagnosed in males and females

respectively.

CLASSIFICATION: Hypogonadism

Primary Secondary

hypogonadism

Congenital*

Aquired Hypogonadism

Hormonal Fertility

Symptoms • Girls with Hypogonadism will not begin

menstruating and it may affect their height and breast development. Onset in women after puberty causes cessation of menstruation, lowered libido, loss of body hair.

• In boys it causes impaired muscle and beard development and reduced height. In men it can cause reduced body hair and beard, enlarged breasts, loss of muscle, and sexual difficulties.

Treatment

• Male Hypogonadism is most often treated with testosterone replacement therapy (TRT)*.

• For women, estrogen and progesterone are replaced.

Obesity

• Obesity is a major problem in this syndrome and is one of the most frequent reasons for medical consultation.

• It is present in 75% of patients. • Excess weight gain does not usually begin until 1-2 years

of age. • The cause is unknown but the mechanism of obesity

appears to be a complex combination of hyperphagia and altered disposal of calories.

• Definition: excessive weight that may impair

health

• How do we measure If someone is obese?– Body Mass Index (BMI)= ( Weight in Kilograms / ( Height in Meters ) x ( Height in Meters ) )

(92/1.63*1.63)=34.62kg/m2

Obesity

• Simple equation…when you eat more than you use.it is stored in your body as “fat”. – Causes

• Global shift in how we eat• Western diet of processed

food• Higher sugar, fat and

calories in what we eat• Less nutrients• Reduced intake of

vitamins and minerals

Obesity -Cause

• With more people gaining too much weight. there are health issues to be consider like – Cardiovascular disease– Diabetes type 2– Musculoskeletal disorders – Cancers-endometrial, cervical and

colon– Infertility – Gallstones – Premature death and disability

What does obesity do to our bodies?

• The only treatment is to :

Nutrition counts! – Nutrition is

everything! Healthy foods, fruits, vegetables,

– a colorful diet is best!

– Low sugar, low fat– Play an hour a day!

Obesity –Treatment WHO states:

Fruits and vegetables need to be part of the daily diet to prevent disease such as obesity and noncommunicable disease

WHO recommends at least 400 gms of fruit and vegetables each day…This will prevent chronic disease related to overweight and obesity

Heart diseaseDiabetesCancers

• It is well known that obesity is preventable. It is caused by eating more than we need…so how can we prevent obesity? – Each of us can…according to WHO

• Have a balance of energy and healthy weight• Limit how much fat we eat…we need to eat

some..but not too much. • Increase fruits and vegetables• Limit sugars• Increase exercise to at least 30-60 minutes per day

on most days!

Obesity –Essential Understanding

Renal abnormalities • Renal abnormalities can lead to life-

threatening problems. • Some patients have structural abnormalities in

the form of dysplastic kidneys with irregular contour and cystic dilatation of collecting ducts and calyces.

• About 15% develop symptomatic renal impairment, with 5% going into end-stage renal failure.

Harnett JD, Green JS, Cramer BC, et al. The spectrum of renal disease in Laurence-Moon-Biedl syndrome. N Engl J Med 1988; 319: 615-618.

Initial investigation and follow uprecommendations for a person with

Bardet-Biedl syndrome

investigations

• Electroretinogram (ERG)• Renal ultrasound• ECG & echocardiogram• molecular testing• CT/MRI brain scan/renal• Electroencephalogram (EEG)• Statementing of educational

needs• Registration of blindness• Speech assessment & therapy

Follow up

• Six monthly• Urine analysis

• Annually• Blood pressure• Urea & creatinine levels

jmg.bmj.com on December 17, 2013

Treatment

• There is not a specific treatment for BBS.• Literature says that treatment should be

symptomatic.• There are no contra-indications of this

syndrome for surgical and non surgical management of other symptomatic diseases.

J Med Genet 1999;36:437–446

THANK YOU