HYPOTHYROIDISM-HYPOTHYROIDISM- MANIFESTATIONS & MANIFESTATIONS & MANAGEMENTMANAGEMENT

HYPOTHYROIDISM-HYPOTHYROIDISM- MANIFESTATIONS & MANIFESTATIONS & MANAGEMENTMANAGEMENT

Dr. Sachin Verma MD, FICM, FCCS, ICFC

Fellowship in Intensive Care Medicine

Infection Control Fellows Course

Consultant Internal Medicine and Critical Care

Web:- http://www.medicinedoctorinchandigarh.com

Mob:- +91-7508677495

Thyroid

Pituitary

Hypothalamus

TRH (+)

TSH (+)

T3, T4 (-)

T3, T4 (-)

HyperthyroidismHyperthyroidism HypothyroidismHypothyroidism

Patients of Thyroid Disorders Present AsPatients of Thyroid Disorders Present As

With GoiterHypothyroid

Without Goiter

With GoiterHyperthyroid

Without GoiterEuthyroid With Goiter

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HypothyroidismHypothyroidismCauses

With GoiterHashimoto’s Thyroiditis

I2 deficiency goiter

Drug induced goiter

(Li, Amiodarone, PAS, ethionamide, Rifampicin)

Due to goitrogens

Riedel’s thyroiditis

Without GoiterHashimoto’s Thyroiditis

Post ablative(radioactive I 2)

After thyroidectomy

Congenital hypothyroidism

Secondary hypothyroidism

(Sheehan syndrome)

HYPOTHYROIDISMIODINE DEFICENCY is the most common

cause of hypothyroidism worldwide.

In Iodine sufficient areas, Autoimmune disease (HASHIMOTO’S THYROIDITIS) is most common.

HYPOTHYROIDISM HYPOTHYROIDISM Common presentation

Symptoms

Dry & coarse skin- 76%

Cold intolerance – 64%

Puffiness of face- 60%

Sweating- 54%

Wt gain-54%

Paresthesia - 52 %

Constipation- 50%

Aches & pains non specific

Signs

Ankle reflex absent- 77%

Bradycardia - 58%

Somnolence

Diastolic hypertension

Depression

Anemia

Menorrhagia

Infertility

HYPOTHYROIDISM HYPOTHYROIDISM Uncommon Presentations.Uncommon Presentations.

Hoarseness of voice

Deafness

Ascites

Pericardial & pleural effusion

Carpel tunnel syndrome

Impotence

Galactorrhoea & Amenorrhoea

Cardiac failure

Psychosis

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• Thyroid Disease Can Have Widespread Effects

Thyroid

• Increased LDL Cholesterol

• ElevatedTriglycerides

Liver

• Constipation

• Decreased GI

Activity

Intestines

• Decreased Fertility

• Menstrual Abnormalities

• May Harm Development of Infant

ReproductiveSystem

• Depression

• Decreased Concentration• General Lack of Interest

Brain

•Decreased Heart Rate

•Increased/DecreasedBlood Pressure

•Decreased CardiacOutput

Heart

• Decreased Function

• Fluid Retention and

Edema

Kidneys

HashimotoHashimoto’’s Thyroiditiss ThyroiditisIN USA

Above 50 years Female – 10% Hypothyroid

Above 60 years Male – 10% Hypothyroid

In India prevalence rate of Hypothyroid is quite high

but data is not available.

Hashimoto’s ThyroiditisHashimoto’s Thyroiditis

Commonest cause of hypothyroidism

Most of the patients never develop goitre

Symptoms develop very gradually

So difficult to Diagnose!

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Hashimoto’s ThyroiditisPainless Goiter/ No Goiter

InvestigationsT3 T4 TSHHigh titers of TPO ab. (almost 100%)

TreatmentLife long Thyroxin

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Viral ThyroiditisViral Thyroiditis

Painful Goiter (Usually small) , fever , sorethroat

Natural History:

Hyperthyroid 2 – 3 months

Hypothyroid 2-6 months

Euthyroid

Few Patients may remain Hypothyroid Life Long04/12/23 13

Viral Thyroiditis: TreatmentViral Thyroiditis: Treatment

Pain - Aspirin (600mg 4-6hrly) / NSAIDS

Steroids – 40- 60 mg/ day according to severity

Hyperthyroid – Propranolol

Hypothyroid – May require Thyroxin(50-100µgm)

Euthyroid – After 6 months – 1 year

No Drug Required

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POST-PARTUMPOST-PARTUM THYROIDITIS THYROIDITIS

Post-partum thyroiditis (PPT) is an autoimmune,

painless inflammation of the thyroid gland that

occurs within a year in 5% to 10% of all

pregnancies.

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Etiology and PathogenesisEtiology and Pathogenesis Microchimerism:

(Fetal cells in maternal blood)

The presence of residual fetal cells which get

attached to the maternal thyroid gland during

pregnancy, induces autoimmune reactions as

maternal immunosuppression is lost after delivery.

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Post Partum ThyroiditisPost Partum ThyroiditisNatural History:

Hyperthyroid 2 - 3 months

Hypothyroid 2 - 6 months

Euthyroid

25% of Postpartum Thyroiditis Patients will develop Hypothyroidism after 5-10 years of delivery

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Atypical Presentations of Atypical Presentations of Postpartum ThyroiditisPostpartum Thyroiditis

A Thyrotoxic phase followed by a return to

normal thyroid function

A Hypothyroid phase alone

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Initial tests for diagnosis of Initial tests for diagnosis of Thyroid DysfunctionThyroid Dysfunction

Primary Test

TSH

Additional Test

Free T4

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TSH raised (>3.5-5.5 according to the lab)

Free T4 decreased

Total T4 decreased

.

Free T3 May be normal in 25% cases of early hypothyroidism

Hypothyroidism: Initial Hypothyroidism: Initial DiagnosisDiagnosis

Thyroid Ultrasound

Relatively unimportant test

Sensitive tool to ascertain size and number of

thyroid nodules.

Important tool in the follow up of a thyroid nodule

if it is not to be operated

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Thyroid ScanThyroid Scan

WILL SHOW

UPTAKE

UPTAKE

NORMAL UPTAKE

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Thyroid ScanThyroid Scan

UPTAKE WITH GOITRE ( cold)

Thyroiditis, Thyroid carcinoma

DO FNAC

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Thyroid ScanThyroid Scan

UPTAKE WITH GOITRE (hot)

Graves’ Disease

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Thyroid ScanThyroid Scan

NORMAL UPTAKE WITH GOITRE

Colloid Goitre, Puberty Goitre, Adenoma

DO FNAC04/12/23 26

COMMON THYROID AUTOANTIBODIES*

ANTIGEN ANTIBODY

TSH receptor TSHRAb (TSH Receptor Antibody)

Thyroglobulin TgAb

Thyroid Peroxidase TPO Ab

* Williams’ textbook of Endocrinology: 10th edition; chapter, 10 pg 36

GROUP TPO Ab

General Population 8-10%

Graves Disease 50-80%

Autoimmune Thyroiditis 90-100%

Relatives of Patients 40-50%

Pregnant Women 14%

* Williams’ textbook of Endocrinology: chapter, 10 pg 361

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Dose of Levothyroxine depends on the degree of Hypothyroidism, Age & General health condition of the patient

Usually daily replacement dose is 1.6µgm/Kg body weight

Start with Low Dose

Treatment Of Hypothyroidism

If Dose Missed, What To Do???

One Dose Missed Take Two Tablets

Two Dose Missed Take Three Tablets

Three Dose Missed Take Regular Dose

Treatment Of Hypothyroidism

WHEN SHOULD I TAKE IT ??

EMPTY STOMACH 30 mins BEFORE CALORIC

MEAL

Treatment Of Hypothyroidism

Follow up of a case of HypothyroidismFollow up of a case of Hypothyroidism

Serum TSH levels should be measured after 6-8

weeks of therapy and dosages should be adjusted

accordingly

Target TSH levels should be between 1-2 mU/l

Once a stable TSH is achieved, it should be

estimated every year

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Follow up of a case of HypothyroidismFollow up of a case of Hypothyroidism

Patient on Thyroxine TSH NORMAL

WHAT SHOULD I DO??

Most of these patients are Hashimoto’s thyroiditis . They will require life long treatment Donot stop the Donot stop the drug drug Continue Thyroxine

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INTERPRETATION OF INTERPRETATION OF

THYROID FUNCTION TESTSTHYROID FUNCTION TESTS

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Situation 1

TSH Free T3 Free T4

Normal Normal Normal

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Diagnosis

Normal Euthyroid

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Situation 2

TSH Free T3 Free T4

High NormalNormal

/Decreased

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Diagnosis

SubClinical / Early Hypothyroidism

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Situation 3

TSH Free T3 Free T4

Increased Decreased Decreased

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Hypothyroidism

Diagnosis

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Situation 4

TSH Free T3 Free T4

Low High High

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Diagnosis

Hyperthyroidism

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Situation 5

TSH Free T3 Free T4

LowLow or Normal

Low

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Diagnosis

Secondary HypothyroidismOr Sheehan’s

Syndrome 04/12/23 44

SHEEHAN’S SYNDROME Female

Excessive blood loss during delivery

No lactation amenorrhoea

Weakness,lethargic, anemia Depigmentation of areola, Shiny

skin Loss of pubic & axillary hair Low B.P.

SHEEHAN’S SYNDROMETreatment Hormone replacement therapy including

glucocorticoid (prednisone 5+2.5 mg/d), Thyroxine (75-150µgm/d)

If lady wants periods- estrogen & progesterone preparations can be given.

GOAL To maintain T4 level in the upper half of range

TSH CANNOT BE USED TO MONITOR THERAPY

During pregnancy requirement of thyroxin

increases by 25-50µg/d during pregnancy

Even on mild Thyroxin hormone deficiency

there are chances of low IQ and developmental

delay of the child

Hypothyroid And pregnancyHypothyroid And pregnancy

Hypothyroid And pregnancyHypothyroid And pregnancyThyroid Hormone exists in two forms :

Free (Active) & Bound (with thyroxine binding globuline).

In Pregnancy increased Estrogen, increases TBG which in turn increases Total T4 & T3 level

However Free T4, Free T4 REMAINS NORMAL.

SO Free T4 should be used in the treatment and follow up during pregnancy & not total T4

Hypothyroidism In ElderlyHypothyroidism In ElderlyIn Patients Above 60 Rule Out Coronary

Artery Disease

If Coronary Artery Disease Present Or Suspected:

Start Thyroxine With Low Dose And Then Increase The Dose Gradually Otherwise Angina May Precipitate.

50

Myxedema ComaPrecipitating factors :

Infection, trauma, stroke, cardiovascular, hemorrhage drug overdose, diuretics

Signs and Symptoms :

Usually older age presenting as : Mental confusion, hypothermia,

bradycardia, ↓ Na, ↓ glucose, ↑ CO2, ↓ WBC, ↓ Hct, ↑ CPK

↓ EKG voltage

Myxedema ComaTreatment

ICU transfer,

IV levothyroxine 500 µg bolus followed by 50-100µg/d (same dose can be given through NG tube),

antibiotics, ventilation, hydrocortisone IV, passive warming, careful volume management

As T4 to T3 conversion is impaired so leothyronine is recommended but has a potential to provoke arrythmias.

Myxedema Madness.When being crazy is not in your head BUT IN THYROID

Delirium With Auditory Hallucinations & Paranoid Delusions

Takes The Form Of Psycotic Depression Or Pure Psycosis.

No Cognitive Impairement

Treatment- Thyroxine

Thank YouThank You

Sick Euthyroid SyndromeAny acute, severe illness can cause abnormalities of

circulating TSH or Thyroid hormone levels in the absence of underlying Thyroid disease.

Major cause - Release of cytokine IL-6

Most common pattern ---- LOW T3 SNDROME---- in total & unbound

T3 levels with normal T4

& TSH T4 T3 rT3De iodination

LOW T4 SYNDROME ----

1. Very sick patient may exhibit a dramatic fall in Total T3 & T4

2. Poor prognosis

In Acute Liver disease initially Total T3 & T4 levels due to TBG release; these levels become subnormal as the disease progress

Renal disease is often accompanied by low T3 levels

In early stages of HIV T3 & T4 levels rises,. T3 levels falls with progression to AIDS , but TSH remains normal

Sick Euthyroid Syndrome

Diagnosis is supported by

History of thyroid disease Previous thyroid function tests

History of Drugs that may affect thyroid hormones

Measurement of rT3 together with FT3 , FT4 and TSH

ONLY RESOLUTION OF TESTS WITH CLINICAL RECOVERY CAN ESTABLISH THIS DISORDER

Sick Euthyroid Syndrome