Physiology Case Studies
a) Hemophilla : Hemophilia A (classic hemophilia), is caused by the deficiency of Factor VIII.
Hemophilia B (also called Christmas disease, for the name of the family the disorder was first
observed in), is caused by the deficiency of factor IX.
b) Similarly to most recessive sex-linked, X chromosome disorders, haemophilia is more likely
to occur in males rather than females. This is because females have two X chromosomes
while males have only on lacking a 'back up' copy for the defective gene meaning, the
defective gene is guaranteed to manifest in any male who carries it.
c) Yes there are chances of the boy’s sister being a carrier- Females have two X chromosomes,
while males have one X and one Y chromosome. A female carrier of hemophilia has
the haemophilia gene on one of her X chromosomes. When a hemophilia carrier female is
pregnant, there is a 50/50 chance that the hemophilia gene will be passed on. If the gene is
passed on to a son, he will have the disease. If the gene is passed on to a daughter, she will
be a carrier.
d) There is no definite cure for haemophilia as it is a genetic disorder , it can be controlled with
regular infusions of the deficient clotting factor, i.e. factor VIII in haemophilia A or factor IX in
a) Patient suffering from diabetes mellitus type 2.
b) Polyuria is a condition usually defined as excessive or abnormally large production and
passage of urine. Polydipsia refers to excessive thirst. Polyuria and polydipsia are due to
osmotic diuresis secondary to sustained hyperglycemia Results in loss of glucose,
water, and electrolytes. It may reflect decreased fluid intake, increased urine output, or
excessive loss of water and salt. Polyphagia (increased hunger) initially due to depletion of
water, glycogen, and triglycerides. Then due to reduced muscle mass as amino acids are
diverted to form glucose, and ketone bodies.
c) Diabetes mellitus type 2 is due to non response in insulin not due to the lack of insulin.
Presence of insulin in blood decreases lipolysis which causes a decrease in ketone bodies
production in body as a consequent there is no ketone bodies released in urine. It indicates
patient is not suffering from diabetic ketoacidosis (DKA). DKA results from an absolute
shortage of insulin; in response the body switches to burning fatty acids and producing
acidic ketone bodies that cause most of the symptoms and complications.
a) Ovulation test and fertility monitors are designed to predict ovulation by detecting LH (or
Luteinizing Hormone) or measuring the basal body temperature. There is a slight fall in basal
body temperature prior to ovulation. And , the temperature increases after ovulation.
b) Pregnancy tests determine pregnancy through the detection of the hormone hCG (Human
Chorionic Gonadotropin) in a woman's urine.
c) i. Ovulation tests work by detecting luteinizing hormone (LH) in a woman's urine. Just
preceding ovulation, women experience an "LH surge" - a sudden, dramatic, and brief rise in
the level of luteinizing hormone. A positive result on an ovulation test means that the woman
will most likely become fertile over the next three days - with peak fertility at 36 hours
following the LH surge. Second test: measurement of basal body temperature after ovulation
shows an increase in temperature due to thermogenic effect of progesterone.
ii. Pregnancy tests determine pregnancy through the detection of the hormone hCG (Human
Chorionic Gonadotropin) in a woman's urine. Human Chorionic Gonadotropin (hCG) is a
glycoprotein hormone secreted by the developing placenta shortly after fertilization. The
appearance of hCG soon after conception - and its subsequent rise in concentration during
early gestational growth - make it an excellent marker for the early detection of pregnancy.
d) Follow the safe period ( rhythm method ) or advised to use oral contraceptives to control
a) i. The patient showed an increased BMR (+40 %). This may due to several factors like high
level of stress or thyroid hormones in the body.
ii. The serum cholesterol of the patient are 100 mg% which in a normal range.
iii. The normal pulse rate at rest averages about 72/min, .the patient showed a high basal
rate (120/min) (tachycardia).
b) The patient may be suffering from thyrotoxicosis. Due to sustained palpitations may be
accompanied by tachycardia, dyspnoea on exertion, weight loss despite high appetite,
diarhea, tremors, nervousness, diaphoresis and heart intolerance.
c) Investigate for serum T3, T4 and TSH.
a) From the above statement, the patient can be related to cushing’s syndrome. Cushing’s
syndrome is a hormonal disorder caused by prolonged exposure of the body’s tissues to high
levels of the hormone cortisol. Sometimes called hypercortisolism.
Symptoms are :
• severe fatigue
• upper body obesity, a rounded face, increased fat around
the neck, and relatively slender arms and legs
• skin become fragile and thin, bruises easily, and heals poorly
• weak muscles
• reddish or pink stretch marks may appear on the abdomen,
thighs, buttocks, arms, and breasts
• high blood pressure
• high blood glucose
• increased thirst and urination
• irritability, anxiety, or depression
• a fatty hump between the shoulders
b) Increase amount of cortisol. Cortisol reduce the immune system’s inflammatory response.
c) The blood glucose value will increase. This is because of abnormal increase of glucocorticoid.
cortisol counteracts insulin, contributing to hyperglycemia by stimulation of
hepatic gluconeogenesis and inhibition of the peripheral utilization of glucose by decreasing
the translocation of glucose transporters to the cell membrane.
b) Increase serum calcium levels
c) decreased calcium excretion in urine
d) increased phosphate excretion in urine
e) extensive decalcification and, occasionally, large punched-out cystic areas of the bone that
are filled with osteoclasts.
Osteoporosis or fractures associated with hyperparathyroidism is caused by the
high parathyroid hormone secreted by overactive parathyroid gland(s). Excess parathyroid
hormone (PTH) acts indirectly on osteoclasts, which in turn leads to the removal of calcium
from the bones. Thus, the high calcium in the blood comes from the bones. .
a) From the biochemical test, it shows that the patient is having polyuria and polydipsia
because the urine that the patient passed out is more than the normal range which is 15 L in
24 hours rather than the normal output is 1.5 L/day and the patient also had excessive thirst
sensations. There is no sugar in urine, therefore the provisional diagnosis is Diabetes
b) Polyuria occurs because of complete or partial failure of ADH secretion or also known as
arginine vasopressin (AVP). It will cause decreased in renal water reabsorption by collecting
ducts, will leads to polyuria (diuresis of dilute urine)(up to 3-20 L/day). It will then stimulate
thirst and increased water intake (polydipsia).
c) Other conditions are Diabetes mellitus, kidney disease and adrenocortical dysfunction.
d) The treatment is administration of a synthetic analog of ADH, desmopressin that can be
given by injection, as nasal spray, or orally and rapidly restores urine output toward normal.
a) Endocrine causes for short stature:
• pituitary dwarf - due to growth hormone deficiency-secondary to decrease in GHRH
• hypothyroid dwarf - due to thyroid hormone deficiency
• cushing syndrome - due to excess of circulating glucocorticoids
b) Signs & symptoms:
PITUITARY DWARF HYPOTHYROID DWARF
(GHRH) (THYROID HORMONE)
Plumpness (fatness) Gross retardation of ‘mental’ and ‘physical’
Delicate extremities, body proportion according to Body proportion remains infatile
the chronological age
Delayed skeletal and dental development Earlier its onset, more severe is the delay inn
growth and skeletal maturation
Small genital Associated hypothyroidism features
a) It indicates the symptoms of myasthenia gravis where difficulty in breathing and swallowing is
present. The parenteral form (neostigmine methylsulphate) should be used.
Although myasthenia gravis may affect any voluntary muscle, muscles that control eye
and eyelid movement, facial expression, and swallowing are most frequently affected.
In most cases, the first noticeable symptom is weakness of the eye muscles. In others, difficulty in
swallowing and slurred speech may be the first signs. The degree of muscle weakness involved
in myasthenia gravis varies greatly among patients, ranging from a localized form, limited to eye
muscles (ocular myasthenia), to a severe or generalized form in which many muscles sometimes
including those that control breathing are affected. Symptoms, which vary in type and severity,
may include a drooping of one or both eyelids (ptosis), blurred or double vision (diplopia) due to
weakness of the muscles that control eye movements, unstable or waddling gait, weakness in
arms, hands, fingers, legs, and neck, a change in facial expression, difficulty in swallowing and
shortness of breath, and impaired speech (dysarthria).
b) Myasthenia gravis is caused by a defect in the transmission of nerve impulses to muscles. It
occurs when normal communication between the nerve and muscle is interrupted at the
neuromuscular junction - the place where nerve cells connect with the muscles they control.
Normally when impulses travel down the nerve, the nerve endings release a neurotransmitter
substance called acetylcholine. Acetylcholine travels through the neuromuscular junction and
binds to acetylcholine receptors which are activated and generate a muscle contraction.
In myasthenia gravis, antibodies block, alter, or destroy the receptors for acetylcholine at the
neuromuscular junction which prevents the muscle contraction from occurring. These antibodies
are produced by the body's own immune system. Thus, myasthenia gravis is an autoimmune
disease because the immune system which normally protects the body from foreign organisms -
mistakenly attacks itself.
c) Neostigmine is used to improve muscle tone in people with myasthenia gravis . By interfering
with the breakdown of acetylcholine, neostigmine indirectly stimulates both nicotinic and
muscarinic receptors. Unlike physostigmine, neostigmine has a quaternary nitrogen; hence, it is
more polar and does not enter the CNS. Its effect on skeletal muscle is greater than that of
physostigmine, and it can stimulate contractility before it paralyzes. Neostigmine has short
duration of action, usually thirty minutes to two hours. Neostigmine binds to the anionic site of
cholinesterase. The drug blocks the active site of acetylcholinesterase so the enzyme can no
longer break down the acetylcholine molecules before they reach the postsynaptic membrane
receptors. This allows for the threshold to be reached so a new impulse can be triggered in the
next neuron. In myasthenia gravis there are too few acetylcholine receptors so with the
acetylcholinesterase blocked, acetylcholine can bind to the few receptors and trigger a muscular
a) Costochondritis-Is the condition in which there is an inflammation or injury at the cartilage
joining the ribs to the sternum, costochondral.Which will then could lead to tenderness and
pain in the anterior chest wall. Costochondritis are closely related and most often confused
and interexchange with Tietze syndrome. However, one very big difference between these
two conditions is that Tietze syndrome does not have swelling at the injured/involved cartilage
of ribs.As the case states that there is only constrictive pain and no swelling stated,thus these
condition could be most probably due to Costochondritis. Pain radiating along the border of
ulnar is due to the many nerve branches away from the chest area. The severity of the pain is
proportional to the exertion is because any activity such as exercise or deep breathing will
stretch the inflamed cartilage, thus will cause significance pain.
b) ECG is normal, because this condition only mimics that of myocardial infarction, however it
has nothing related to heart diseases. Since the affected area is only the cartilage located
behind the sternum, no organs are involved. Thus, it signifies the heart is not affected and in
c) - Careful use of nonsteroidal anti-inflammatory medications.
- Local heat or ice might relieve the pain.
- Avoid unnecessary heavy exercises or activities.
a) Partial thickness of burn injury and may damage dorsal root ganglia and peripheral nerves.
b) It is because the touch receptors are not damage and only the pain and temperature
receptors are damage.
c) It is the dorsal root ganglia that sense pain and temperature.
d) It may be a disuse atrophy or damage of the peripheral nerves and nerve endings that
innervate the small muscles.
a) Hemorragic shock (hypovolumic shock) due to excessive loss of blood.
b) Extreme blood loss can lead to all the signs mention above. Hypotension and oliguria are the
highlight of shock. Vasoconstriction leads to cold clammy hand because shutting down the
blood in periphery will occur and all the remaining blood will be diverted to the major organs
like heart and kidneys. This also will cause pale, cold and extreme weakness. Restlessness
can be due to reflex tachycardia because of hypovolumia. It can progress to confusion.
c) Immediate treatment is infusion. Crystalloid solution and electrolyte to replace the amount of
blood loss. (Crystalloid solution is a hypertonic solution which will be used immediately for
a) The pain is due to increased secretion of gastric acid in the stomach. This may be a case of
peptic ulcer disease.
b) It is a substance to stimulate gastric acid secretion. Hence it is tested in this patient to
increase his stomach’s gastric secretion.
d) Duodenal ulcer pain usually occurs between meals when the stomach is empty and relieved
by food especially milk. Food would neutralise the acid in stomach.
e) Vagotomy will reduce the acidity of the stomach, by denervating the partial cells that produce
a) There is lesion on the neural pathway above the anterior horn cell or motor nuclei of the
cranial nerves and this cause the nerve fibers traveling from the anterior horn of the spinal
cord to the relevant muscle are affected. Because of these reasons the child has pain in the
back and neck and had a fever.
b) According to the symptoms and signs of the child, the lesion is the upper motor neuron
lesion, which is in contrast to a lower motor neuron lesion and it is caused by the lesion of the
neural pathway above the anterior horn cell or motor nuclei of the cranial nerves.
c) Diagnosis — hemiplegia.
Hemiplegia is a condition in which the limbs on one side of the body have severe weakness.
Hemiplegia is more severe than hemiparesis, where one half of the body has less marked
weakness. Hemiplegia may be congenital or acquired from an illness or stroke.
Hemiplegia is not an uncommon medical disorder. In elderly individuals, strokes are the most
common cause of hemiplegia. In children, the majority of cases of hemiplegia have no
identifiable cause and occur with a frequency of about one in every thousand births. Experts
indicate that the majority of cases of hemiplegia that occur up to the age of two should be
considered to be cerebral palsy until proven otherwise.
a) The patient has hemiplegia, paralysis of one side of the body.
b) Damage to Corticospinal tract(descending tract or motor tract) at the level of internal
capsule. Damage to the lenticulostriate arteries in the internal capsule.
a) It is a pernicious anemia which is one type of megaloblastic anemia.
b) It is caused by deficiency of vitamin B12 absorption. Vitamin B12 and folic acid are
essential for formation of red blood cell. From the investigation, the most important result
revealed is the presence of achlorhydria. Achlorhydria is where the production of gastric
acid in the stomach is absent. Gastric acid is important because it secrete together with
intrinsic factor (IF) by parietal cell. When there is less or no secretion of IF, Vitamin B12
cannot be absorbed and leads to pernicious anemia.
c) The treatment for pernicious anemia by two ways either by ingestion or by injection.
Ingestion of vitamin B12 tablet is done either orally or sublingual (under the tongue) and
both equally well absorb. Oral supplementation allows B12 to be absorbed in places other
than the terminal ileum (where B12 absorption usually takes place). However, if oral and
sublingual repletion of B12 is inadequate, the patient may require B12 injections, which are
usually given once a month, bypassing the need for gastrointestinal absorption altogether.
a) The patient is diagnosed with obstructive jaundice. This is caused by obstruction of bile duct
which prevents the passage of bile into intestine due gall stone or any tumor.
b) The stool are pale in colour due to the absence of stercobillinogen. The feaces contains
excess fat which indicate impairment of fat digestion and absorption in absence of bile. This
condition is known as steatorrhea.
c) Van den Bergh is a test to indentify in an increase in serum billirubin . As than the patients’s
serum billirubin is excessively high normal level (0.2 -1.0 mg/100day). Hence it gave a direct
a) The patient had incomplete transaction of spinal cord. Due to spinal shock, the patient
suffered from temporary quadriplegia.
b) The incomplete lesion of spinal cord at cervical level.
c) As there is no inhibitory effect of the descending tract (due to lesion of upper motor neuron),
It lead to the hyperactive reflexes for a stimulation.
d) Functional activity of urinary bladder recovers first during the recovery stage or stage of reflex
a) Anterior cord syndrome
b) Damage is in the Anterior column /portion of Spinal cord at thoracolumbar region
c) Touch sensation is intact because the tract that carries touch sensation is in the dorsal or
posterior white column.
d) Temperature and pain sensation is absent due to interruption of the spinothalamic tract.
a) The patients has a parkinson’s disease. It is characterized by tremor, a slowing of physical
movement (bradykinesia), muscles rigidity and monotonous speech.
b) It is a degenerative disorder of substantia nigra. The primary symptoms are the results of
decreased stimulation of the motor cortex by the basal ganglia, normally caused by the
insufficient formation and action of dopamine, which is produced in the dopaminergic
neurons of the brain (specifically the substantia nigra). Secondary symptoms may include
high level cognitive dysfunction and subtle language problems.
c) It is due to the loss of dopamine neurons in the substantia nigra. Dopamine is involved in
planning and programming of movements and act as muscle tone inhibition. Loss of
dopamine neuron unnatural stillness or frozen quality. Tremor may or may not be present.
d) Levodopa (or L-dopa) has been the most widely used treatment for over 30 years. L-dopa is
transformed into dopamine in the dopaminergic neurons by dopa-decarboxylase. Since motor
symptoms of PD are produced by a lack of dopamine in the substantia nigra the
administration of L-dopa temporarilly diminishes the motor symptomatology.
Carbidopa and benserazide are peripheral dopa decarboxylase inhibitors They help to
prevent the metabolism of L-dopa before it reaches the dopaminergic neurons and therefore
reduce side effects
Muscles and nerves that control the digestive process may be affected by PD, therefore, it is
common for patients to experience constipation and gastroparesis. A balanced diet is hence
recommended to help improve digestion. Diet should include high-fiber foods including whole
grain breads and cereals as well as fruits and vegetables and plenty of water, while it is
important to avoid caffeine and alcohol and iron salts. Excessive protein should also be
avoided because affects the absorption of Levodopa.
a) Provisional diagnosis is Tabes dorsalis; it is due to syphilis. There is degeneration of sensory
neurons and stabbing pains in the trunk and legs and unsteady gait and incontinence and
impotence. The degenerating nerves are in the dorsal columns (posterior columns) of
the spinal cord
b) Sensory tract- posterior column tract - fasciculus gracilis and fasciculus cuneatus
c) Incoordination of lower limbs while walking: The person having problem to sense of the
ground he touch, thus he need to see the place where he put his foot as this also have
relation with the loss of proprioception. This type of walk is known as the tabetic gait.
Loss of sense of position: The person already have problem in sensory system thus it give
effect on the sense of positioning the stimulus when the physician do the sensory test on him.
Altered muscle tone: Destruction of the sensory limb of the spindle reflex. The deep tendon
reflexes are also diminished or absent; for example, the "knee jerk" or patellar reflex may be
lacking (this is known as Westphal's sign).
a) Presence of albumin in urine shows nephrotic failure. Right ventricular hypertrophy and
elevated P wave show that patient is suffering from cardiac failure. Oliguria shows a kidney
b) Backward failure of the right ventricle leads to congestion of systemic capillaries. This
generates excess fluid accumulation in the body. This causes swelling in foot and ankle. In
progressively severe cases, ascites (fluid accumulation in the abdominal cavity causing
swelling) and hepatomegaly (enlargement of the liver) may develop. JVP is a good
approximation of right atrial pressure, which is a major determinant of right ventricular end
diastolic volume. The increased JVP is due to right sided heart failure.
c) Elevated P wave is because of Right sided heart failure, which is due to right ventricular
d) The patient suffered of elevated JVP, this causes the enlargement of right ventricular heart.
Elevated P wave is due to the increase in the atria depolarization before atrial contraction
a) Type of anemia does this patient have is Iron Deficiency Anemia.
b) Cause of the anemia is due to parasitic infection (by hook worm).This parasite cause
intestinal bleeding which lead to iron deficiency. The other possible cause is due to blood lost
during menses as this woman can be categorized in premenstrual woman.
c) For iron deficiency anemia, the main treatment is done by iron supplement.
d) Eosinophilia is caused by increase in eosinophil count due to allergic condition of parasitic