case 13 - tiredness Flashcards
what main conditions can cause tiredness?
blood-related = anaemia, underactive thyroid, coeliac disease, diabetes, glandular fever
head-related = depression, anxiety
sleep-related = chronic fatigue syndrome, sleep apnoea, restless legs syndrome
what’s the difference between tiredness and fatigue?
tiredness = can be relieved by sleep and rest
fatigue = overwhelming tiredness that cannot be relieved by sleep and rest
what type of anaemias are associated with tiredness?
most commonly, iron-deficiency anaemia (type of microcytic anaemia)
also, vitamin B12 or folate deficiency anaemia (type of macrocytic anaemia)
who is at a high risk of developing iron-deficiency anaemia?
women with heavy periods (menorrhagia)
pregnant women
what is the most common cause of anaemia in men and postmenopausal women?
problems with the stomach and intestines
e.g. ulcer OR taking NSAIDs
why and how can NSAIDs cause anaemia?
decrease the activity of blood platelets = decreased clot formation
= increased risk of bleeding and ulcer formation
= can lead to anaemia
what is an ulcer?
a localised breach/sore (gap, erosion) in the surface continuity of the skin or mucous membrane (stomach, small intestine, oesophagus)
besides anaemia, which (opposite) blood condition can cause tiredness?
haemochromatosis
what is haemochromatosis?
rare inherited condition that affect men and women between 30-60
build-up of iron in the body leading to iron-overload
(deposition in the liver, joint pancreas etc)
who does haemochromatosis affect most?
men and women between 30-60
what is sleep apnoea?
a condition where your throat narrows or closes during sleep and repeatedly interrupts your breathing
what does sleep apnoea result in?
loud snoring
decrease in blood oxygen levels
what is the main symptoms/impact of sleep apnoea?
waking up often during the night
feeling exhausted the next day (due to disrupted sleep)
who is affected by sleep apnoea the most?
overweight middle-aged men
what factors worsen sleep apnoea?
increased alcohol and smoking
what is an underactive thyroid?
too little thyroid hormone (thyroxine) in your body
due to reduced production by the thyroid gland
besides tiredness, what are the additional symptoms of an underactive thyroid?
weight gain
aching muscles
dry skin
what is an underactive thyroid alternatively known as?
hypothyroidism
how can an underactive thyroid be diagnosed?
blood test (to test TSH, T4 levels)
who is most likely to be affect by hypothyroidism?
women as they get older
who is most likely to be affected by hypothyroidism?
women as they get older
what is coeliac disease?
autoimmune condition wherein the immune system overreacts to the gluten ingested in the diet
(i.e. small intestine is hypersensitive to gluten = leading to difficulty in digesting food)
what is gluten?
a protein in wheat, barley and rye
(helps foods maintain their shape, acting as a glue that holds food together)
which foods are gluten-rich?
can be found in foods like pasta, bread, cakes and cereals
besides tiredness, what are the symptoms of coeliac disease?
diarrhoea
anaemia
bloating
weight loss
how is coeliac disease diagnosed?
blood test (specific)
what is chronic fatigue syndrome?
severe and disabling fatigue that goes on for at least 4 months
what is chronic fatigue alternatively known as?
myalgic encephalomyelitis
how long does ME usually last for?
at least four months
besides tiredness, what are the other symptoms of ME?
muscle or joint pain as well
which diabetes is tiredness a symptom of?
type 1 and type 2 diabetes both
besides tiredness, what are the symptoms of diabetes (type 1)?
polydipsia
polyuria
nocturia
weight loss
what is glandular fever?
a common viral infection that causes fatigue, along with fever, sore throat and swollen glands
besides tiredness, what are the symptoms of glandular fever?
fever
sore throat
swollen glands
who is most affected by glandular fever?
teenagers and young adults
how long does glandular fever last?
symptoms usually clear up in 4-6 weeks but fatigue can linger for several more months
how and why can depression cause tiredness?
core symptoms = anergia, anhedonia, low mood
can also cause disruption to sleep + early waking up = more tiredness during the day
what is restless legs syndrome?
an overwhelming urge to move your legs, which can keep you awake at night
what are the symptoms of restless legs syndrome?
an overwhelming urge to move legs at night
unpleasant crawling sensation
deep ache in legs
legs may jerk spontaneously through the night
why can restless legs syndrome lead to tiredness?
the urge to move/jerk legs or the deep ache of the leg muscles at night is so overwhelming = can keep people awake at night
= leading to tiredness
how can anxiety lead to tiredness?
constant uncontrollable feelings of anxiety that are so strong they interfere with their daily life
what is GAD?
generalised anxiety disorder
long-term condition that causes you to feel uncontrollably anxious about a wide range of situations and issues, rather than one specific event
who is most commonly affected by GAD?
common condition that affects women slightly more than men
besides tiredness, what else do people with GAD experience?
feelings of anxiety and irritability
to the nearest 10%, what percentage of patients who present to a GP with fatigue have a diagnosis made?
approx 66%
to the nearest 10%, what percentage of patients who present to a GP have a condition that is detected on blood tests?
approx <10%
= highlights the importance of a good, comprehensive history and a good physical examination
how many GP consultations are due to fatigue?
approx 7%
name four other possible differential diagnoses
jet lag disorder
pregnancy
(chronic) heart failure
insomnia
vitamin D deficiency
( + many other reasons = lack of sleep, insomnia, medication, stress etc)
what is important to consider when thinking of possible differential diagnoses?
need to think of frequency e.g. common to rare AND consequence e.g. less serious (e.g. nutritional deficiencies) to very serious (e.g. cancers)
how do you narrow down to fewer/a maximum of two differential diagnoses?
by asking more questions
(i.e. taking a more comprehensive history)
which of the following blood tests would be ordered to investigate hypothyroidism?
FBC
U&E
vitamin D
TFTs
HbA1c
CRP
coeliac screen
autoimmune screen
EBV serology
FBC (full blood count)
U&E (urea & electrolytes)
vitamin D
TFTs (thyroid function tests)
HbA1c
why would a FBC be done to investigate tiredness?
to test for classic signs of anaemia, haematological malignancy and WBC levels for signs of infection
why would a U&E be done to investigate tiredness?
look at electrolyte abnormalities and eGFR
why would a vitamin D test be done to investigate tiredness?
to test for signs of vitamin D deficiency
why would TFTs be done to investigate tiredness?
to test for possible hypothyroidism
why would HbA1c be done to investigate tiredness?
family history of diabetes and to test for abnormal glucose levels
why wouldn’t an autoimmune screen be done to investigate tiredness?
can be an extensive test that requires loads of time and effort so much justificatio is needed before requesting one
what do the following blood test results indicate and why?
indicate primary hypothyroidism due to the reduced fT3 and fT4 levels and the elevated TSH levels
what are the symptoms of hypothyroidism?
explain the mechanism of action of primary hypothyroidism, using the HPA axis
decreased production of thyroid hormones by the thyroid gland causes a compensatory increase of TSH due to the negative feedback loop
what is primary hypothyroidism?
low levels of blood thyroid hormone due to destruction of the thyroid gland
(destruction can be due to autoimmunity, surgery, radiation, medication etc)
what is secondary hypothyroidism?
either, more commonly, when the pituitary produces insufficient TSH
or
less commonly, when the hypothalamus produces insufficient thyrotropin-releasing hormone (TRH) = sometimes referred to as tertiary hypothyroidism
what would be the expected TFT results for a patient with primary hypothyroidism?
low fT3 and fT4
elevated TSH
what would be the expected TFT results for a patient with secondary hypothyroidism?
low fT3 and fT4
low TSH
differentiate between primary and secondary hypothyroidism
primary = due to direct damage to the pituitary gland
secondary = due to pituitary or hypothalamic damage/disease
what is tertiary hypothyroidism?
when the hypothalamus produces insufficient thyrotropin-releasing hormone (TRH)
reducing TSH and therefore fT3 and fT4 production downstream
what is the most common type of autoimmune hypothyroidism?
Hashimoto’s thyroiditis
how can you differentiate between secondary and tertiary hypothyroidism?
practically impossible to do so as TRH levels are immeasurable (as it is in the portal circulation, not the systemic circulation)
so cannot tell if TSH levels are low due to hypothalamic/pituitary disease
= both fall under the category of secondary hypothyroidism sometimes
name the immune cells
eosinophils
basophils
neutrophils
macrophages
dendritic cells
natural killer (NK) cells
B lymphocytes
T lymphocytes
name the antigen-presenting cells
macrophages
dendritic cells
B cells