Glucose in Urine

Is glucose present in normal urine?

Normal urine contains no glucose because the kidneys are able to reclaim all of the filtered glucose back into the bloodstream.

What does glucose in urine mean?

'Glucose in urine' is glycosuria or glucosuria, and refers to the excretion of glucose into the urine.

What are the causes of glucose present in urine?

Glycosuria can be due to:
1. Diabetes mellitus (most common)
2. Intrinsic problem with glucose reabsorption in kidneys (rare)

Glycosuria is nearly always caused by elevated blood glucose levels, most commonly due to untreated diabetes mellitus. Excess glucose in the blood spills over and exits in urine.

Rarely, glycosuria is due to an intrinsic problem with glucose reabsorption within the kidneys themselves, a condition termed renal glycosuria.

What causes osmotic diuresis?

Glucose is an osmotic molecule - it attracts water. Glycosuria leads to excessive water loss into the urine with resultant dehydration, a process called osmotic diuresis.

Explain the filtration of glucose in the kidney.

Blood is filtered by millions of nephrons, the functional units that comprise the kidneys. In each nephron, blood flows from the arteriole into the glomerulus, a tuft of leaky capillaries. The Bowman's capsule surrounds each glomerulus, and collects the filtrate that the glomerulus forms.

The filtrate contains waste products (e.g. urea), electrolytes (e.g. sodium, potassium, chloride), amino acids, and glucose.

Explain the reabsorption of glucose in the kidney.

The filtrate passes into the renal tubules of the kidney. In the first part of the renal tubule, the proximal tubule, glucose is reabsorbed from the filtrate, across the tubular epithelium and into the bloodstream.

The proximal tubule can only reabsorb a limited amount of glucose. When the blood glucose level exceeds about 8.9-10.0 mmol/L (160 – 180 mg/dL), the proximal tubule becomes overwhelmed and begins to excrete glucose in the urine.

What happens when blood glucose exceeds the renal threshold for glucose?

Glucose will be excreted into urine; glucose appears in urine; glucose can be detected in urine.

What is the renal threshold of glucose?

The point at which high glucose exceeds the renal threshold of glucose (RTG) causes it to overflow into urine.

The average renal threshold of glucose is 8.9-10.0 mmol/L (160-180 mg/dL).

It varies in individuals and in different physiological states; it is lowered in pregnancy and in children.

What is the renal threshold for glucose in children and pregnant women?

Children and pregnant women, may have a low RTG (less than ~7 mmol/L or 126 mg/dL glucose in blood to have glucosuria).

What are the other conditions where glucosuria may occur?

Glucosuria can occur temporarily from:

1. emotional stress or pain, 
2. hyperthyroidism, 
3. alimentary hyperglycemia, and 
4. meningitis.

What is renal glycosuria?

If the RTG is so low that even normal blood glucose levels produce the condition, it is referred to as renal glycosuria.

What is the urine dipstick test?

The urine dipstick test is a convenient urine test where a reagent test strip is used and dipped in freshly voided urine for the detection of pH, specific gravity (S.G.), protein, ketone, glucose, hemoglobin, red blood cells (rbc), white blood cells (wbc), and others.

Different dipsticks test for different things or combinations in urine.

The urine dipstick test is often used for OSCEs, a type of practical examination format that is used in medical schools.

What is the relationship between glucose detected by dipstick and blood/plasma glucose levels?

External links:
http://wiki.answers.com/Q/How_do_you_lower_blood_glucose#slide=4
http://www.elmhurst.edu/~chm/vchembook/624diabetes.html
http://en.wikipedia.org/wiki/Glycosuria

Blood Glucose: Fasting vs. Random

Synonyms:
Random Blood Glucose (RBG)
Random Blood Sugar (RBS)
Random glucose
Random sugar
Blood sugar
Blood glucose


Introduction

A blood glucose test measures the amount of a type of sugar, called glucose, in your blood.

The random glucose test is blood glucose level determined on a non fasting sample, taken randomly from a non fasting subject. This test is also called random blood glucose (RBG).

It assumes a recent meal and therefore has higher reference values than the fasting glucose test. The fasting glucose test is called fasting blood glucose (FBG) or fasting plasma glucose (FPG) since plasma is usually used for the determination of glucose, whether random or fasting.

Regulation of blood glucose

Glucose comes from carbohydrate foods (eg rice, pasta, bread, roti canai, mee goreng, pisang goreng, ubi, karipap, nasi lemak, etc). It is the main source of energy used by the body, and lasts 4 hours after normal food intake.

Glucose levels in the blood is controlled by insulin. Insulin is a hormone that helps the body's cells use the glucose found in the blood. Insulin is produced in the pancreas and released into the blood when the amount of glucose in the blood rises, for example, after you have eaten (postprandial).

Normally, your blood glucose levels increase slightly after you eat. This increase causes your pancreas to release insulin so that your blood glucose levels do not get too high (hyperglycaemia). Blood glucose levels that remain high over time can damage your eyes, kidneys, nerves, and blood vessels. These are referred to as complications of hyperglycemia, which occurs in long-standing diabetes or chronic diabetes.

Types of glucose determinations

There are several different types of blood glucose tests or glucose determinations. There are reasons why some tests are chosen over others. Some tests require fasting blood samples, while others do not and patients do not need to fast (as for random blood glucose).

1. Fasting blood sugar (FBS)
2. 2-hour postprandial (2HPP) blood sugar
3. Random blood sugar (RBS)
4. Oral glucose tolerance test (OGTT)
5. Glycohemoglobin A1c (HbA1c, A1c, A1C)

Why is blood glucose determined?

Blood glucose tests are done to:

1. Check for pre-diabetes and diabetes.
2. Monitor treatment of diabetes.
3. Check for diabetes that occurs during pregnancy (gestational diabetes).
4. Determine if an abnormally low blood sugar level (hypoglycemia) is present. A test to measure blood levels of insulin and a protein called C-peptide may be done along with a blood glucose test to determine the cause of hypoglycemia. To learn more, see the topic C-Peptide.

What is fasting blood glucose?

Fasting blood sugar (FBS) measures blood glucose after you have not eaten for at least 8 hours. It is often the first test done to check for pre-diabetes and diabetes.

What is 2HPP?

2-hour postprandial blood sugar measures blood glucose exactly 2 hours after you start eating a meal. This is not a test used to diagnose diabetes. It is part of a modified OGTT (see OGTT).

What are Normal Blood Glucose Levels?

The amount of glucose in your blood changes throughout the day and night. Your levels will change depending upon when, what and how much you have eaten, and whether or not you have exercised.

Normal Blood Sugars

A normal fasting (no food for eight hours) blood sugar level is between 70 and 99 mg/dL.
A normal blood sugar level two hours after eating is less than 140 mg/dL.

Reference values

The reference values for a "normal" random glucose test in an average adult are 79 - 140 mg/dl (4.4 - 7.8 mmol/L), between 140 - 200 mg/dl is considered pre-diabetes, and > 200 mg/dl is considered diabetes according to ADA guidelines (patients should visit the doctor or a clinic for additional tests. However, a random glucose of > 200 mg/dl does not necessarily mean patients are diabetic).

Conversion units for glucose

http://www.soc-bdr.org/conversion_glucose_mg_dl_to_mmol_l/index_en.html

What is hypoglycemia?

Hypoglycemia is low levels of glucose in blood.

A test to measure blood levels of insulin and a protein called C-peptide may be done along with a blood glucose test to determine the cause of hypoglycemia.

What to do when your blood glucose is too low.

You can eat 3 dried dates and drink some water to bring up your blood glucose levels. You can also drink glucose solution.

What is random blood glucose?

This test is also called a casual blood glucose test, but this term is hardly used.

Random blood sugar (RBS) measures blood glucose regardless of when you last ate.

Blood sample is taken randomly (untimed) from a non fasting patient. The patient does not have to fast when coming to the clinic or hospital.

Since blood glucose levels fluctuates throughout the day, several random measurements may be taken throughout the day.

Random testing is useful because glucose levels in healthy people do not vary widely throughout the day.

Blood glucose levels that vary widely may mean a problem.

What is pre-diabetes?

Pre-diabetes is a condition before full-fledged diabetes occurs. It is a temporary and transient period. It is a reversible condition and diabetes will disappear.

Patients who are diagnosed with pre-diabetes are at high risk of developing diabetes. You can prevent or delay diabetes by increasing physical activity, eating healthy foods, and maintaining or losing weight or obtaining normal weight.

What is impaired fasting glucose?

In pre-diabetes, patients have impaired fasting glucose levels. This means the cells in the body have become resistant and the cells can no longer take up glucose (glucose uptake becomes nil).

Pre-diabetes is also called impaired fasting glucose (IFG).

If left untreated IFG patients progress to become diabetic. At IFG stage, things are reversible. Pre-diabetes is reversible. Diabetes has no cure but it can be controlled.

How is pre-diabetes diagnosed?

Pre-diabetes is diagnosed by any one of the following:

1. A fasting blood glucose in between 100-125 mg/dL
2. An A1c between 5.7 - 6.4 percent
3. Any glucose value between 140 mg/dL and 199 mg/dL during a two-hour 75g oral glucose tolerance test. [The US uses 75g glucose load. We use 100g glucose load in Malaysia.]

What is an OGTT?

An oral glucose tolerance test (OGTT) is a series of blood glucose measurements taken after you drink a sweet liquid that contains glucose (eg 100g glucose mixed in a glass of water).

The OGTT is used to diagnose pre-diabetes and diabetes.

When is OGTT performed?

1. The OGTT is commonly used to diagnose diabetes that occurs during pregnancy (gestational diabetes or gestational diabetes mellitus, GDM). This test is not commonly used to diagnose diabetes in a person who is not pregnant. 
2. OGTT is also conducted with a hormone test (eg growth hormone, GH) in patients who have abnormally large features (gigantism, acromegaly). In acromegaly, OGTT is abnormal and glucose does not suppress the growth hormone levels.

What is a modified OGTT?

A modified OGTT is shorter and easier for doctors to do for their patients. 

A modified OGTT has only 2 values - before glucose intake and 2 hours after glucose intake (2HPP).

A 2HPP is part of a modified OGTT. 

How do you use glucose readings to diagnose diabetes?

Diabetes is diagnosed by ANY ONE of the following:

1. Two consecutive fasting blood glucose tests that are equal to or greater than 126 mg/dL
2. Any random blood glucose that is greater than 200 mg/dL
3. An A1c test that is equal to or greater than 6.5 percent. 
4. A two-hour oral glucose tolerance test with any value over 200 mg/dL
5. Sometimes you may have symptoms of fatigue, excessive urination or thirst, or unplanned weight loss. However, often people have no symptoms of high blood glucose and find a diabetes diagnosis surprising.

What is the criteria for diagnosing diabetes?

Criteria for Diagnosing Diabetes

(American Diabetes Association's criteria)

To be diagnosed with diabetes, you must meet one of the following criteria:

1. Have symptoms of diabetes (increased thirst, increased urination, and unexplained weight loss) and a blood sugar level equal to or greater than 200 milligrams per deciliter (mg/dL). The blood sugar test is done at any time, without regard for when you last ate (random plasma glucose test or random blood sugar test).
2. Have a fasting blood sugar level that is equal to or greater than 126 mg/dL. A fasting blood sugar test (fasting plasma glucose) is done after not eating or drinking anything but water for 8 hours.
3. Have a 2-hour oral glucose tolerance test (OGTT) result that is equal to or greater than 200 mg/dL. An OGTT is most commonly done to check for diabetes that occurs with pregnancy (gestational diabetes).
4. Have a hemoglobin A1c (HbA1c) that is 6.5% or higher.
5. The diagnosis of diabetes needs to be confirmed by repeating the same blood sugar test or doing a different test on another day.

What is A1c?

A1c is an easy blood test that gives a three month average of blood sugars. It indicates the amount of glycosylation that has occurred in the past 3 months. It tells the doctor whether patients controlled their diet or otherwise.

Glycohemoglobin A1c measures how much sugar (glucose) is stuck to red blood cells. 

This test can be used to diagnose diabetes.  

HbA1C or just A1C is an abbreviation for glycosylated hemoglobin. The blood levels of HbA1C can identify average blood glucose levels for an individual over approximately 120 days, the life span of a red blood cell.

It also shows how well your diabetes has been controlled in the last 2 to 3 months and whether your diabetes medicine needs to be changed.

What is normal A1c?

If patients controlled their blood glucose levels, HbA1c is less than 7%.
If patients did not control their blood glucose levels, HbA1c is greater than 7%.

What is eAG?

The result of your A1c test can be used to estimate your average blood sugar level. This is called your estimated average glucose, or eAG.


External links:
http://www.webmd.com/diabetes/blood-glucose
https://www.virginiamason.org/WhatareNormalBloodGlucoseLevels
http://en.wikipedia.org/wiki/Random_glucose_test
http://diabetescenter.blogspot.com/2008/07/renal-threshold-for-glucose.html

Lung Function Tests

http://www.webmd.com/lung/lung-function-tests

http://www.webmd.com/lung/bronchoscopy-16978

http://www.advanceweb.com/web/AstraZeneca/focus_on_asthma_copd_issue5_Bronchodilator/issue5.html

http://www.lung.org/lung-disease/bronchiectasis/

http://www.webmd.com/asthma/guide/peak-flow-meter

http://www.webmd.com/a-to-z-guides/blood-culture

http://www.nlm.nih.gov/medlineplus/ency/article/003804.htm

Osmolarity vs. Osmolality and Osmotic Gap

OSMOLARITY

Osmolarity:
- is an estimation of the osmolar concentration of plasma
- is proportional to the number of particles per litre of solution
- is a calculated value (from a formula or an equation)
- is derived from the values determined for Na+, K+, urea and glucose concentrations
- is expressed as mmol/L
- is unreliable in various conditions:
   - hyperlipidaemia in nephrotic syndrome (pseudohyponatraemia)
   - hyperproteinaemia

Calculation of osmolarity:

The following equations can be used to calculate osmolarity:

Equation 1:

Calculated osmolarity = 2 (Na+) + 2 (K+) + Glucose + Urea (all in mmol/L)

The doubling of sodium accounts for chloride, its main associated anion.
The exclusion of potassium is because K+ values are too small compared to sodium.

Equation 2:

Calculated osmolarity = 2 (Na+) + Glucose + Urea (all in mmol/L)

The doubling of sodium accounts for the negative ions associated with sodium (mainly chloride).
The exclusion of potassium is because the values are too small compared to sodium.

Normal values for osmolarity:

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OSMOLALITY

Osmolality:
- is an estimation of the osmolar concentration of plasma
- is proportional to the number of particles per kilogram of solvent
- is expressed as mOsmol/kg (the SI unit is mmol/kg but mOsmol/kg is still widely used).
- is measured by clinical laboratories using an osmometer. There are 2 types:
  - a freezing-point depression osmometer
  - a vapour-pressure depression osmometer

Normal values for osmolality:

Normal osmolality of extracellular fluid (ECF) is 280-295 mOsmol/kg.

Uses of osmolality:
- it provides a snapshot of the number of solutes present in the blood (serum), urine, or stool
- it is ordered to help evaluate the body's water balance
- it is ordered to find out its ability to produce and concentrate urine
- it is used to help investigate low sodium levels (hyponatremia)
- it is used to detect the presence of toxins such as methanol and ethylene glycol (see osmotic particles)
- it is used to monitor osmotically active drug therapies such as mannitol, used to treat cerebral edema.
- it is also ordered to help monitor the effectiveness of treatment for any conditions found to be affecting a person's osmolality.


OSMOTIC PARTICLES

Osmotic particles attract or "pull" water:

1. Sodium, glucose, and urea account for the majority of the osmotically active particles in the blood.
2. Extraneous osmotically active substances are ethanol, ethylene glycol, mannitol, methanol, or other toxins.

OSMOTIC GAP

Osmotic gap:
- is also called osmolal gap
- is an arbitrary measure of the difference between the actual osmolality (measured by the laboratory) and the calculated osmolarity

Normal values for osmotic gap:

Osmotic gap is normally less than 10-15 mOsmol/kg (refer local laboratory for range).

Increased values for osmotic gap:

Where the osmotic gap is increased, it indicates the presence of other osmotically active solutes which are not taken into account in the calculated osmolality - eg, in methanol or ethylene glycol ingestion. Victims commit suicide by drinking methanol. Ethylene glycol is radiator fluid for cars. Victims accidentally drink ethylene glycol.

Typical causes of an increased osmolar gap:

acetone, decreased serum water, ethanol, ethylene glycol, glycerol, hyperlipidemia, hyperproteinemia, isopropyl alcohol,laboratory error, sorbitol


OSMOMETER

So far we have used the Gonotec Osmomat 3000 osmometer (freezing-point depression). It requires a small amount of sample (50 microlitres). There are tubes for smaller volumes (15 microlitres).

http://www.gonotec.com/products/osmomat-3000

External links:
http://www.patient.co.uk/doctor/osmolality-osmolarity-and-fluid-homeostasis
http://labtestsonline.org/understanding/analytes/osmolality/tab/test
http://www.rnceus.com/renal/renalosmo.html
http://www.globalrph.com/anion_gap_review.htm
http://www.wolflabs.co.uk/laboratory-products/osmometers/osmomat-3000/10092120
http://pdfs.wolflabs.co.uk/service/Gonotec_Osmometer_3000_manual.pdf
http://camblab.info/wp/wp-content/uploads/2014/03/mod_200plus.gif

Pituitary Gland

Biochemistry

THEORY

FUNCTIONS OF PITUITARY HORMONES

Hormones secreted from the pituitary gland help control the following body processes:
1. Growth
2. Blood pressure
3. Some aspects of pregnancy and childbirth including stimulation of uterine contractions during childbirth
4. Breast milk production
5. Sex organ functions in both males and females
6. Thyroid gland function
7. The conversion of food into energy (metabolism)
8. Water and osmolarity regulation in the body
9. Water balance via the control of reabsorption of water by the kidneys
10. Temperature regulation
11. Pain relief

DISEASES INVOLVING THE PITUITARY GLAND

Some of the diseases involving the pituitary gland are:
1. Central diabetes insipidus caused by a deficiency of vasopressin.
2. Gigantism and acromegaly caused by an excess of growth hormone. --- PBL Ph2 Yr2 MD Wk1 Topic1
3. Hypothyroidism caused by a deficiency of thyroid-stimulating hormone.
4. Hyperpituitarism, the increased (hyper) secretion of one or more of the hormones normally produced by the pituitary gland.
5. Hypopituitarism, the decreased (hypo) secretion of one or more of the hormones normally produced by the pituitary gland.
6. Panhypopituitarism a decreased secretion of most of the pituitary hormones.
7. Pituitary tumours.
8. Pituitary adenomas, noncancerous tumors that occur in the pituitary gland.

GROWTH HORMONE (GH)

GH is growth hormone, or somatotropin
GH is a single polypeptide chain containing 191 amino acids.
GH has structural similarity with prolactin and human placental lactogen.
GH is synthesised by acidophils (somatotropic cells) of anterior pituitary.
GH has a circadian rhythm;
- plasma concentration of GH is less than 2 ng/ml during day time,
- with secretory peak appearing 3 hr after meals.
- maximum level of GH is seen during deep sleep;
- this peak is required for anabolic and repair process.

GH secretion is regulated by the balance between GHRH and GHIH (somatostatin).
The regulation of secretion is predominantly inhibitory.
Hypoglycemia stimulates GH secretion.
Hyperglycemia suppresses GH secretion.

The metabolic effect of GH is partly mediated by somatomedin.
Somatomedin is also known as insulin-like growth factor-1 (IGF-1).
The growth of long bones is stimulated by IGF-1.
IGF-1 level is almost always raised in acromegaly.
A single plasma level of IGF-1 reflects mean 24-hour GH level and is useful in diagnosis.

GH increases the uptake of amino acids by cells.
GH enhances protein synthesis, and produces positive nitrogen balance.
The anti-insulin effect of GH causes lipolysis and hyperglycemia.
The overall effect of GH is to stimulate growth of soft tissues, cartilage and bone.
GH is anabolic.

Excess secretion by GH secreting tumour, leads to
- gigantism in children
- acromegaly in adults.

Deficiency of GH secretion in early childhood results in pituitary dwarfism.
Dwarfism may also result from congenital deficiency of GH due to end organ resistance.
Dwarfism is treated by giving GH produced by recombinant technology.

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PRACTICAL

SERUM GH

The samples are collected during sleep and also during waking hours to assess the circadian rhythm.

Random plasma GH is elevated.

GH SUPPRESSION TEST (glucose suppression test)

Basis of the GH suppression test:
Dynamic tests like stimulation of secretion by insulin induced hypoglycemia and inhibition by hyperglycemia are undertaken to arrive at a diagnosis.

Procedure:
Measure plasma glucose and GH during a standard OGTT.

Interpretation:
(i) In normal person:
Normally in healthy individuals, oral administration of 100 g glucose causes a reduction of the GH level to <5 br="" ml.="" ng=""> (ii) In acromegaly:
Acromegalics (with GH excess) fail to suppress GH level. In acromegaly, the GH levels may decrease, increase or show no change. However, they do not decrease to less than 5 ng/ml and this lack of response establishes the diagnosis. High GH levels are sustained in acromegalics.

(iii) Patient:
In this patient, the GH level is not suppressed (ie sustained) and remained high during the test, Therefore, patient suffers from acromegaly.

BLOOD GLUCOSE

Check if patient is diabetic.
Check for hyperglycaemia.

RBS is high (>11.1 mmol/L) - patient has hyperglycaemia most likely due to diabetes mellitus as patient is symptomatic with lethargy, polyuria and polydipsia.

OGTT

Oral glucose tolerance test (OGTT). Administer 100 g glucose solution (dissolve in a glass of water).

HBA1C

Glycosylated haemoglobin (HbA1c) provides an index of the average blood glucose concentration over the last 6 weeks (lifespan of Hb molecules).

URINALYSIS (urine dipstick test)

Test urine for sugar, ketones and protein.
Urine sugar - check for glycosuria (in polyuria and polydipsia)
Urine ketone - check for ketonuria which occurs in diabetic ketonuria
Urine protein - check for proteinuria (renal involvement in diabetes)

Urine sugar is positive - glycosuria is not diagnostic of diabetes but indicates the need for further investigation.

Urine protein is negative - indicates there is no renal involvement as diabetic nephropathy.

Urine ketone is negative - indicates patient does not have ketoacidosis.

UREA, CREATININE and ELECTROLYTES (renal profile)

Serum urea, creatinine and electrolytes - to check for renal status as patient has polyuria.

Serum sodium and potassium are normal - indicate that patient does not have hypoadrenalism, hypothyroidism (hyponatraemia), or diabetes insipidus (hypernatraemia).

Serum urea - decreased serum urea in acromegaly.

Serum creatinine - increased serum creatitine in gigantism and acromegaly.

CALCIUM

Serum calcium - high with hypercalciuria in acromegaly. Matches with renal stone formation.

Hypercalciuria and hyperphosphaturia are observed in acromegalic patients. It is well known that acromegaly is associated with the disturbances of Ca and PO4 metabolism, and consequently with an increased risk of Ca stones.

ENZYMES

Heart muscle enzyme:
Creatinine kinase (CK) - elevated in myopathy

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Abnormal findings

ENT / ORL-HNS:
Coarse facies - Increased level of GH causes thickening of the soft tissues, overgrowth of the malar, frontal and facial bones combined with prognathism to produce the coarse facial features called acromegalic facies.
Facial and infraorbital puffiness - ?
Broad nose
Big ear

Dentistry:
Widening of the teeth / interdental separation
Prognathism - widely spaced teeth

Speech Pathology:
Large tongue
Thick lips
Deep voice

Medicine:
Hypertension - investigate further
CXR
ECG
Echocardiogram
Urinalysis
Fasting blood for lipids and glucose
Serum urea, creatinine and electrolytes

Cardiology:
Heart failure
Proximal myopathy

Ophthalmology:
Visual field examination
Visual field testing by Goldmann perimetry - it can assess any visual field defect as upper temporal quarantonopias and bitemporal hemianopias. Perimetry can also assess the tujour size.
Papilloedema - increased intracranial pressure from the pituitary tumour causes edema of the optic disc.

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Endocrinology

Pituitary
- anatomy of the pituitary gland
- hormones released by the anterior lobe of pituitary: GH, ACTH, LH, FSH, TSH, aMSH (intermediate lobe), PRL, bLPH
- hormones released by the posterior lobe of pituitary: ADH, oxytocin
- processes involved in the release of these hormones
- biological functions of these hormones
- control mechanisms that affect hormone production, release and function
- types of pituitary tumours
- hyperfunction, hypofunction

Assessment of anterior pituitary reserve or function - as patient may have hypopituitarism:
Basal LH
FSH
Testosterone
ACTH
Cortisol
Free/Total T4
TSH

Triple Stimulation Test
LHRH/GnRH, TRH, insulin tolerance test (ITT) can be done to assess the function of the anterior pituitary. Early LH failure can occur

followed by hypothyroidism and hypoadrenalism.

Hypothyroidism (free/total T4 is low with a low or normal TSH level) must be excluded since this is a cause of hyperprolactinaemia.

Serum prolactin
Mild to moderate hyperprolactinaemia occurs in pituitary tumour.
Pituitary tumour is suspected if patient has papilloedema, indicating increased intracranial pressure from a pituitary tumour.

Serum prolactin - is due to hyperprolactinaemia that can result from a pituitary tumour, which is evident from the CT scan of the brain.

Endocrinology/Medicine:
Galactorrhoea
Edema plus other signs of hypopituitarism
Goitre

-----

Patient workup:

History
Physical examination
Presenting clinical features
Pathological features
Radiological features
Laboratory investigations
Deduce possible patient problem

-----

Medicine

Pathophysiology of:
I. Pituitary hypersecretion:
   - Gigantism
   - Acromegaly - face, hands **
   - Prolactin-induced infertility
   - Craniopharyngioma
   - Cushing's disease
II. Pituitary hyposecretion:
   - Pituitary dwarfism
   - Panhypopituitarism
   - Diabetes insipidus

-----

Radiology

Imaging studies:

Skull X-ray - enlargement/widening of the pituitary fossa, double flooring, calcification

MRI scan of the pituitary - to rule out suspicion of a pituitary tumour as patient has history of headache and papilloedema.

Lateral X-ray of the heel - assessment of soft tissue thickness by measuring heel pad thickness.

X-ray of hand - Large hands, thickened and bulky with blunt spade-like fingers (similar findings in the toes - spade-like feet)
Large hands and sweaty - The hands enlarge from increased soft tissue growth. Sebaceous activity increases causing excessive sweating.
Increased joint space due to hypertrophy of cartilage, cortical thickening with result in squared appearance of the metacarpals.
Small exostoses in the areas of tendons and ligament insertion and are obvious in the head of the metacarpals.
Tufting of the terminal phalanges producing an "arrow-head" appearance.

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Possible complications:

Cardiovascular problems - CAD, related to HPT and DM
Arthritis - occurs prematurely in spine and weght-bearing joints (hips, knees)
Malignancy - colon cancer is increased.

Arthropathy - disease of the joints
Tight rings - excessive fat

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Treatment and Management

Surgery - vi transphenoid/transfrontal route

Radiotherapy

Medical therapy - using a somatostatin analogue (octreotide) or dopamine agonist (bromocriptine).

Principles of hormone replacement therapy (HRT) in pituitary dysfunction

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Further Reading

Basic and Clinical Endocrinology. Francis S. Greenspan. Acromegaly and gigantism. Clinical findings on page 119.

Steven WJ Lamberts. Non-functioning pituitary tumours and hypopituitarism. Medicine International on Endocrine Diseases. No. 38

Volume 11, 1997, pages 1-4.

JAH Wass. Acromegaly. Medicine International on Endocrine Diseases. No 38 Volume 11, 1997, pages 5-6.
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Videos

http://umm.edu/health/medical/ency/animations/pituitary-gland

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Research & Case Studies

http://www.eje-online.org/content/162/6/1035.full


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Websites

http://www.chronolab.com/point-of-care/index.php?option=com_content&view=article&id=388&Itemid=63

http://www.rnceus.com/renal/renalcreat.html