Haematology/Oncology Flashcards
1
Q
What is the most common cause of microcytic and hypochromic anaemia?
A
Iron deficiency
2
Q
How do red cells appear if they are microcytic and hypochromic?
A
Small and pale (not enough stuff for the pillowcases)
3
Q
How is anaemia defined in children aged 12-14 years?
A
Hb below 120g/L
4
Q
What does the serum ferritin level need to be less than, to confirm iron deficiency?
A
15 micrograms/L
5
Q
What are the causes of iron deficiency anaemia?
A
- Dietary deficiency (poverty, fad diets, exclusive breast feeding >6 months)
- Malabsorption
- Increased loss
6
Q
What are the possible causes for malabsorption in children? (3)
A
- Coeliac disease
- IBD
- High cows milk intake - blocks iron absorption (protein enteropathy)
7
Q
What are the causes of increased blood loss in children that can lead to iron deficiency anaemia? (5)
A
- Meckel’s diverticulum
- Angiodysplasia
- Oesophagitis
- Adolescent girls starting puberty
- NSAIDs
8
Q
What are the symptoms of iron deficiency anaemia? (5)
A
- Pale skin
- Lack of energy
- Breathlessness
- Reduced cognitive and psychomotor performance
- Pica (rare)
9
Q
Why is iron deficiency anaemia a sign, not a diagnosis?
A
Because there is an underlying cause that will require treatment or modifying e.g. diet
10
Q
What is the treatment for iron deficiency anaemia?
A
1.5-2mg/kg iron per day (oral ferrous salt)
11
Q
How long do the ferrous salts need to be taken for and why?
A
3 months after Hb normalises to replenish body stores
12
Q
What are the iron-containing foods that should be encouraged as part of a healthy diet, particularly if someone has iron-deficiency anaemia? (9)
A
- Iron fortified formulas and breakfast cereals
- Meat
- Green vegetables
- Beans
- Egg yolk
- Foods rich in vitamin C (increase absorption of iron)
- Fish
- Apricots, prunes, raisins
- Oatmeal
13
Q
What is important to tell parents when they are giving their children iron supplements?
A
It is normal for their stools to be black
14
Q
What is the main cause of macrocytic anaemia?
A
B12 or folate deficiency
15
Q
What is the other name for vitamin B12?
A
Cobalamin
16
Q
What are the causes of B12 and folate deficiency? (5)
A
- Not enough B12 in the diet
- Intrinsic factor deficiency
- Folate deficiency
- Malabsorption e.g. coeliac disease, IBD
- Drugs e.g. phenytoin, valproate, trimethoprim
17
Q
How may folate or B12 deficiency present? (7)
A
- Pallor
- Fatigue
- Anorexia
- Glossitis
- Developmental delay
- Hypotonia
- Severe cases: subacute combined degeneration of the cord with paraethesia of hands/feet
18
Q
Where is the most common site of solid tumours in children?
A
Brain
19
Q
70-80% of childhood brain tumours occur where? (2)
A
- Infratentorial (region containing the cerebellum)
2. Midline
20
Q
What are the common types of brain tumours that occur in children? (4)
A
- Glial tumours
- Medulloblastoma
- Germ cell tumours
- Craniopharyngioma
21
Q
What % of all childhood malignancies are brain tumours?
A
25%
22
Q
How do infratentorial tumours present? (4)
A
- Raised ICP
- Headaches
- Vomiting
- Cerebellar ataxia
23
Q
How does supratentorial tumours present? (4)
A
- Raised ICP
- Focal neurology
- Hypothalamic/pituitary dysfunction
- Visual impairment
24
Q
Which age range is the most common for children to develop a brain tumour?
A
0-9 years
25
Which is the largest subgroup of brain tumours, accounting for 43% of all brain/CNS tumours?
Astrocytoma (a subgroup of the gliomas)
26
What % of astrocytomas are diagnosed as low grade?
76%
27
What is the name for a grade 1 astrocytoma? (also known as a low grade glioma)
Pilocytic astrocytoma
28
Why are they called pilocytic?
Because the cells are elongated and hair like
29
What are the characteristics of the grade 1 pilocytic astrocytomas?
They are slow growing, unlikely to spread and unlikely to return after being surgically removed
30
Where do pilocytic astrocytomas tend to grow?
In the cerebellum (but can also occur in the optic pathways)
31
Which condition is associated with pilocytic astrocytomas? - and what % of people with this condition will have one?
Neurofibromatosis type 1 (NF1) - affects 10%
32
In which location are the pilocytic astrocytomas associated with a higher mortality rate?
If they are located in the optic pathways - they are far less accessible, so harder to remove
33
What diagnostic imaging can be used to investigate brain tumours?
1. CT (is quick and can be used in emergency situation)
| 2. MRI (better tumour definition)
34
What can be done to treat raised intracranial pressure? (3)
1. Refer to paediatric neurosurgical unit
2. Control tumour swelling with high dose steroids (usually dexamethasone)
3. CSF drainage
35
Where are high grade gliomas typically located?
Supratentorial sites
36
In which age range are high grade gliomas more common?
Older children/teenagers
37
What is the median survival for a brainstem glioma?
<1 year
38
What is the name for the tumours that are high grade embyronal tumours, they are the most common malignant tumours, accounting for 15-20% of all childhood brain tumours?
Medulloblastoma
39
What is the age range most common for medulloblastomas to occur, and in which gender are they more common?
Ages 3 - 8, higher occurrence in males
40
What are the symptoms of a medulloblastoma? (6)
1. Abrupt onset of headaches, especially in the morning
2. Nausea/vomiting
3. Feeling extremely tired
4. Loss of balance and coordination
5. Abnormal eye movements
6. Blurry vision caused by swelling of the optic disc (papilloedema)
41
Where do medulloblastomas occur?
Cerebellum
42
Which genes are linked to brain tumours? (3)
1. RB1 (retinoblastoma gene)
2. NF1 and NF2
3. TSC1 (tuberous sclerosis)
43
Which brain tumour is detected by finding an absent or abnormal light reflex?
Retinoblastoma
44
In addition to an absent light reflex, how else may a retinoblastoma present in terms of eye pathology? (2)
1. Squint
| 2. Visual deterioration
45
When taking a paediatric history, what red flag questions are important to ask if suspecting cancer? (7)
1. Fevers
2. Night sweats
3. Anorexia
4. Weight loss
5. Pallor
6. Bruising
7. Abnormal bleeding
46
What is the most common malignancy in childhood?
Acute lymphoblastic leukaemia (ALL)
47
Where does ALL arise from?
Malignant proliferation of 'pre-B' (B cell origin) most commonly, but can also arise from T-cell precursors.
48
What % of all childhood malignancies does ALL account for?
25%
49
What is the common age range that ALL presents in?
2-6 years
50
What are the signs that may be present in children with ALL? (9)
Normally a relatively quick onset of:
1. Bone marrow expansion/lymphadenopathy
2. Petechiae
3. Testicular enlargement
4. Gum hypertrophy
5. Pallor
6. Abdominal distension due to hepatomegaly/splenomegaly
7. Tachycardia and flow murmur
8. Airway obstruction
9. Pleural effusion
51
What are the specific diagnostic tests for ALL?
1. Bone marrow: morphology, immunophenotype, cytogenetics
2. CSF : for cytospin
3. Clinical examination: inappropriate swelling of testes in males
4. CXR for mediastinal mass
52
What are the risk factors/genetic factors that can predispose a child to developing ALL?
1. Dizygotic twins have a four-fold increase in risk of leukaemia compared with the general population
2. Children with trisomy 21 have a 10/20 fold risk of developing ALL
3. Other chromosomal disorders e.g. Fanconi's anaemia
4. ALL is concordant in 25% of monozygotic twins within a year of the diagnosis of the first twin
53
What is the link between infections and ALL in early childhood?
There is a protective factors in young children being exposed to infections from a young age - if they are insulated from common infections the immune system may respond in an abnormal way when they encounter them at an older age - babies who attend daycare appear to have a decreased risk of developing ALL
54
What are the symptoms of ALL? (11)
1. Fatigue/dizziness/palpitations
2. Severe and unusual joint/bone pain - limp
3. Recurrent, severe infections
4. High temperatures
5. Left upper quadrant fullness
6. Dyspnoea
7. Headache, irritability, altered mental status, neck stiffness
8. Frequent nosebleeds, spontaneous bleeding
9. Unexplained weight loss
10. Night sweats
11. Pale skin
55
What are the differentials for ALL? (6)
1. Infections - EBV, parvovirus B19
2. Aplastic anaemia
3. Lymphoma
4. Metastatic cancer
5. Osteomyelitis
6. Juvenile idiopathic arthritis
56
What happens in ALL?
The bone marrow produces immature WBCs known as blast cells. As the number of blast cells increase, the number of RBCs and platelets decrease, causing symptoms of anaemia.
The blast cells are also less effective compared to mature WBCs, so more vulnerable to infections.
57
What is the four week induction treatment for ALL? (5)
1. Steroids (dexamethasone) throughout induction
2. Weekly IV vincristine
3. IV L-asparaginase
4. IV daunorubicin
5. Intrathecal cytarabine and methotrexate
- aim is to kill the leukaemia cells in the bone marrow, restore the balance of cells in the blood and resolve symptoms
58
What is the second stage of the standard treatment for ALL?
Consolidation CNS-directed therapy - aim is to kill any remaining leukaemia cells in the CNS
59
What is the maintenance medication used to prevent the leukaemia returning?
1. Daily 6-mercaptopruine (6MP), weekly oral methotrexate
2. 4-weekly vincristine IV bolus and oral methotrexate
3. 12 weekly IT methotrexate
-lasts for 2 - 3 years
60
What factors contribute to an adverse prognosis in ALL? (6)
1. Male gender
2. Age <2 years or >10 years
3. High WCC at diagnosis
4. Unfavourable cytogenetics e.g. philadelphia chromosome (t 9,22), AML1 amplification
5. Poor response to induction and failure to remit by day 28
6. High level of minimal residual disease
61
What is Burkitt's type lymphoma?
Mature B-cell ALL
62
What is the overall survival of ALL with current treatment?
80%
63
What is leukaemia?
A malignant proliferation of white cell precursors which occupy the bone marrow. These blast cells can also circulate in the blood and deposit in various tissues.
64
What will a blood test of a child with ALL show?
Markedly raised WCC, anaemia, thrombocytopenia
65
What will testing of the bone marrow show in someone with ALL?
The bone marrow will be replaced with leukaemic lymphoblasts
66
What is Henoch-Schonlein purpura?
A small vessel vasculitis associated with IgA immune complexes.
67
What are the presenting features of HSP? (5)
1. Characteristic skin rash
2. Arthralgia
3. Periarticular oedema
4. Abdominal pain
5. Glomerulonephritis
68
At what age range does HSP tend to occur?
Between 3 - 10 years
69
Which gender is HSP more common in?
Males (twice as common)
70
In which season does HSP tend to peak?
Winter months
71
What often precedes HSP?
URTI
72
Where does the characteristic HSP rash tend to develop?
Normally it is symmetrical and distributed across the buttocks and extensor surfaces of arms, legs and ankles. The trunk is usually spared unless lesions are induced by trauma.
73
How does the rash appear as it develops? i.e. maculopapular
It is initially urticarial then maculopapular and then purpuric
74
Where does the HSP associated arthralgia tend to occur?
The joint pain occurs in the knees and ankles with peri-articular oedema. The pain tends to resolve before the rash goes and the joints do not suffer any long term damage
75
In addition to colicky abdominal pain, what other GI symptoms can HSP cause? (2)
1. Intussusception
| 2. Haematemesis/melaena
76
In terms of the glomerulonephritis caused by HSP, what is present in urine in 80% of cases?
1. Proteinuria
| 2. Haematuria
77
What would indicate in someone with HSP, possible long-term damage to their kidneys? (4)
1. Heavy proteinuria
2. Oedema
3. Hypertension
4. Deteriorating renal function
78
What is sickle cell disease?
Sickle cell disease is abnormal shaped red blood cells during to inheritance of 2 beta-globin genes in which a single AA substitution of glutamine with valine occurs on codon 6.
79
What is the benefit of having heterozygous HbS (not HbSS)?
It protects against malaria
80
What is the problem with having sickle shaped RBCs?
The deformed shape means they form clusters which block blood vessels. It damages large and small blood vessels, and they can be sequestered in the liver and spleen and cause anaemia, intense pain, infections and other complications.
81
What exacerbates the risk of sickle cell RBCs becoming trapped in microcirculation and causing problems?
1. Low oxygen tension
2. Dehydration
3. Cold
82
What is sickle cell anaemia?
When the person has inherited HbS from both parents - homozygous sickle cell disease - HbSS - this is the most common and most severe type.
83
In addition to sickle cell anaemia HbSS, what are the other variants of sickle cell disease?
This means the person has inherited one HbS and one other haemoglobinopathy:
1. Hb C - causing Hb SC
2. Hb DPubjab - HbSDPunjab
3. Hb OArab - HbSOArab
4. Hb B-Thal - Hb Sickle beta-thalassaemia sickle cell disorder
84
What is the name for someone with one sickle haemoglobin and one normal haemoglobin?
Sickle cell trait or sickle cell carrier - HbAS
85
What is the indigence of sickle cell disease in England?
Estimated to affect 1 in 2000
86
In which ethnicity is sickle cell disease most common?
Black African and Black Caribbean people
87
What are the acute complications of sickle cell disease?
The acute complications are the consequences of 'sickling' of erythrocytes (sickle cell crisis), the causes of these include:
1. Intercurrent illness
2. Psychological stress
3. Cold temperatures
4. Pregnancy
5. Dehydration
6. Reduced oxygen in the blood due to high altitude, anaesthesia, exertion
88
What is an acute painful sickle cell crisis?
It usually starts with vague pain, often in the back of limb bones. There may be local warmth, tenderness, swelling and fever.
The pain is thought to be caused by vaso-occlusion by sickled erythrocytes, leading to ischaemic tissue damage and subsequent inflammation and pain.
89
What happens in an acute abdominal sickle crisis? - symptoms (9)
1. Abdominal pain
2. Distention
3. Rigidity
4. Diminished bowel sounds
5. Constipation
6. Hepatic infarction
7. Abscess
8. Hepatic/renal vein thrombosis
9. Mesenteric/colonic ischaemia
90
What is one of the most common infectious complications in people with sickle cell disease?
Osteomyelitis
91
What are the chronic complications associated with sickle cell disease? (12)
1. Chronic pain
2. Chronic anaemia
3. Chronic sickle lung
4. Cognitive impairment
5. Epilepsy (10-15% of people (10 times the incidence than in the general population))
6. Eye problems - neovacularisation, proliferative retinopathy, can lead to retinal detachment
7. Gallstones
8. Impaired nutrition
9. Leg ulcers
10. Priapism (89% of men will have at least one episode)
11. Pulmonary hypertension
12. Renal complications
92
When is sickle cell disease suspected?
If the person is in a high-risk group:
1. In a child age 9-18 months with painful dactylitis (painful swelling of the bones of the hands and feet).
2. Chronic shortening of a digit due to epiphyseal damage
3. Has a sudden severe infection
4. Presents with features of an acute crisis
5. Present with features of chronic complications of sickle cell disease
93
Which cancer is associated with the Philadelphia chromosome?
CML
94
At what age does CML peak?
<1 year
95
What % of childhood cancers does CML account for?
5%
96
Which of the acute leukaemia's is more common in children?
ALL
97
Which of the acute leukaemia's is more common in old people?
AML
98
What do the acute leukaemia's have in common - what do they disrupt?
The accumulation of blast cells interferes with the development and function of healthy white blood cells, red blood cells and platelets
99
What are the causes of ALL?
Either due to a chromosomal translocation or an abnormal chromosome number
100
What are the two chromosomal translocation that are commonly associated with ALL?
t(12;21)
| t(9;22)
101
How can ALL be further classified?
Can be either proliferation of pre-T cells or pre-B cells
102
Which condition is associated with both AML and CML?
Down syndrome
103
Acute leukaemia's share a similar pathogenesis, what is that? (2)
The mutations in the genes causes:
1. The precursor blood cells to lose their ability to differentiate into mature blood cells, this means they are stuck in the blast stage of development, and they don't function effectively.
2. It makes the blast cells divide uncontrollable and in the process take up a lot of space and nutrition in the bone marrow, this means that the other normal blood cells growing in the bone marrow get overcrowded, and the normal blood cells can't get the nutrition they need so its tough for them to survive, this causes cytopaenias - a reduction in the healthy number of blood cells
104
What happens when the blast cells have got so overcrowded in the bone marrow, and they spill out into the blood?
Sometimes they migrate to the thymus or lymph nodes, and settle there, causing these structures to enlarge
105
What are the symptoms of both AML and ALL and why? (6)
1. Fatigue (due to anaemia)
2. Easier bleeding (thrombocytopenia)
3. Increased infections (leukopenia)
4. Pain and tenderness in the bones (increased cell production)
5. Abdominal fullness (hepatosplenomegaly)
6. Pain in the lymph nodes (lymphadenopathy)
106
What would a blood film show for ALL?
Raised lymphoblasts
107
What are the range of blood cells that can be made from the myeloid line of haematopoietic stem cells? (4)
1. Red blood cells
2. Platelets (thrombocytes)
3. Monocytes
4. Granulocytes (neutrophils, basophils, eosinophils)
108
What are the cells that can be made from the lymphoid line of the haematopoietic stem cells? (3)
1. T-cells
2. B-cells
3. Natural kill cells
(all lymphocytes)
109
What causes chronic ML/LL?
chromosomal abnormalities in the haematopoietic stem cells which are destined to become leukocytes
110
What are the different type of chromosomal abnormalities? (3)
1. Deletion
2. Trisomy
3. Translocation
111
What causes CML?
Philadelphia chromosome
112
What causes CLL?
Chromosomal abnormalities that affect especially B cells
113
How does chronic ML/LL differ to acute ML/LL?
In chronic leukaemia's, the cells mature only partially, this is a distinct difference to acute leukaemia's in which the cells don't mature at all.
114
In chronic leukaemia's what is wrong with the partially mature cells?
They don't work effectively, in CML the cells start to divide too quickly, and in CLL the cells don't die as they should.
115
What happens in chronic leukaemia's if the either the CML cells are dividing too quickly or the CLL cells aren't dying as they should?
They will accumulate in the bone marrow and spill out. Just like in acute leukaemia's this result to the healthy cells being overcrowded by these immature cells, taking up the nutrients, and leads to:
1. Cytopenia (low blood cells)
2. Anaemia (low RBCs)
3. Thrombocytopenia (low platelets)
4. Leukopenia
116
What is wrong with the Philadelphia chromosome t(9;22), what fusion happens?
A chromosome 22 gene (BCR) sits next to a chromosome 9 gene (ABL). When they are combined it forms a fusion gene called BCR-ABL gene. These code for a protein also known as BCR-ABL protein.
117
The BCR-ABL protein activates which enzymes?
Tyrosine kinases
118
What are the 4 types of globin chains that can makes up haemoglobin?
1. Alpha
2. Beta
3. Delta
4. Gamma
119
What does the most common form of adult haemoglobin have in terms of the globin chains?
Two alpha and two beta chains
120
What do the majority of fetal haemoglobins have in terms of globin chains?
Two alpha and two gamma components.
121
What are the thalassaemias?
A group of recessively autosomal inherited conditions characterised by decreased or absence of synthesis of one of the two polypeptide chains (alpha or beta) that form the normal adult human haemoglobin molecule, which results in reduced haemoglobin in red cells, leading to anaemia.
122
What are the two types of thalassaemia?
Alpha and beta
123
What are the different classifications of thalassaemia, depending on severity?
Major, intermedia and minor
124
What % of people in the world have beta-thalassaemia and what % have alpa?
```
Beta = 1.5%
Alpha = 5%
```
125
Which chromosome has the alpha gene on it?
Chromosome 16
126
Which chromosome has the beta-globin gene?
Chromosome 11
127
Which type of alpha-thalassaemia would be clinically asymptomatic?
a,-/a,a (thalassaemia heterozygous)
128
Which alpha thalassaemia would result in slightly anaemia, low MCV
Homozygous - a,-/a,-
129
What is the genotype for HbH disease?
a,-/--
| resulting in anaemia, very low MCV and MCH, splenomegaly, and variable bone changes
130
What is alpha thalassaemia major, and what is the name for it?
Hb Bart's - genotype: -,-/-,-
| Severe non-immune intrauterine haemolytic anaemia. Hb Bart's hydrops fetalis, usually fatal
131
What is the beta-thalassaemia trait? (genotype)
-/B2
| Slightly anaemia, low MCV and MCH, clinically asymptomatic
132
When do signs of haemolytic anaemia (pallor, hepatosplenomegaly) occur in alpha and beta thalassaemia respectively?
Alpha t - at birth
| Beta t - several months after birth
133
Where is alpha-thalassaemia most prevalent?
Southeast Asia, Indian subcontinent and some parts of the Middle East
134
How is HbH disease defined in terms of alpha globin genes, and what can be seen on blood film stains?
HbH disease is deletion or inactivation of three alpha globins (oo/ao). It represents alpha thalassaemia intermedia, with mildly to moderately severe anaemia, splenomegaly, jaundice and abnormal RBC indices.
The blood film stains show Heinz bodies.
135
What do Heinz bodies represent?
B-chain tetramers - HbH is unstable and precipitates the erythrocyte, giving it the appearance of a golf ball
136
When do beta thalassaemia symptoms start to occur?
Anaemia starts when the gamma chain production cases and the beta chains fail to form in adequate numbers. This is usually in the latter part of the first year of life, but can be as late as 5 years old because of delay in stopping HbF production.
137
How does beta thalassaemia major in infancy present? (4)
1. Faltering growth/Failure to thrive
2. Vomiting feeds
3. Sleepiness
4. Irritability
138
What are the signs of thalassaemia if left untreated/undetected? (4)
1. Hepatosplenomegaly
2. Bony deformities
3. Marked pallor/slight to moderate jaundice
4. Exercise intolerance, cardiac flow murmur or heart failure secondary to severe anaemia
139
Thalassaemias cause microcytic anaemia. What are the other causes of microcytic anaemias?
1. Iron-deficiency anaemia
2. Sideroblastic anaemia
3. Anaemia of chronic disease
140
What are the differentials for thalassaemias?
1. Acute leukaemia (may require bone marrow aspiration to differentiate)
2. Diamond-Blackfan syndrome
141
What is fetal hydrops?
A condition defined as abnormal fluid accumulation in two or more fetal compartments. These may include ascites, pleural effusion, pericardial effusion and skin oedema. It may also be associated with polyhydramnios and placental oedema.
142
How is fetal hydrops traditionally classified?
Either immune or non-immune
143
What is the primary immune cause of hydrops?
Rhesus blood group isoimmunisation
144
What are the other haematological - haemolytic disorders, associated with fetal hydrops? (3)
1. G6PD
2. Glucose phosphate isomerase
3. Pyruvate kinase deficiency
145
What are the infective causes of fetal hydrops?
1. Parvovirus B19 (20% cases associated with maternal/fetal infection)
2. CMV
3. Syphilis
4. Herpes simplex
5. Toxoplasmosis
6. Hep B
7. Adenovirus
8. Coxsackievirus type B
146
What is Wilms' tumour?
It is a type of renal cancer in children, affecting approximately 80-85 children in the UK each year.
147
How does Wilms' tumour develop?
It develops from immature cells in the embryo. They usually disappear at birth, but in children with Wilms', cluster of primitive kidney cells called nephrogenic rests, can still be found.
148
Which other congenital malformations is Wilms' tumour associated with (in approximately 10% of children with Wilms')
1. Aniridia
2. Hemihypertrophy
3. Macroglossia
4. Beckwith-Wiedemann syndrome
They can be categorised into either 'overgrowth' or non 'overgrowth'
149
What are the signs/symptoms of Wilms' tumour? (5)
1. Distended abdomen
2. Haematuria
3. Abdominal pain
4. UTI
5. Hypertension
150
What exactly is a Wilms' tumour histologically?
An undifferentiated mesodermal tumour of the intermediate cell mass (primitive renal tubules and mesenchymal cells)
151
What investigations can be carried out in someone with a potential Wilms' tumour?
1. Renal USS
2. FBC, renal function and U&Es
3. Intravenous pyelogram
4. Renal angiography
5. CT and MRI scans
152
Which investigation should be avoided in someone with WIlms', as it can make the condition worse?
Transcutaneous renal biopsy
153
Where can Wilms' tumour metastases to, and so what investigation is important to do?
CT chest - lung metastases
154
What is the treatment for Wilms' tumour?
Nephrectomy with chemotherapy - vincristine, dactinomycin and doxorubicin - can be curative
155
What are the survival rates for Wilms' tumour, for both early stages, and then metastatic disease?
90% survival long-term, with 75% for those with metastatic spread
156
In a child (2 years old) with chronic diarrhoea, abdominal distension and failure to thrive, alongside an itchy, vesicular rash on his upper limbs. A blood film shows Howell-Jolly bodies and target cells. What is the most likely cause?
Splenic atrophy - Howell-Jolly bodies are basophilic nuclear remnants in the cytoplasm and are a sign of asplenism. Asplenism is associated with sickle cell disease and rarely, coeliac disease.
157
What is associated with a signet-ring on blood films?
Plasmodium falciparum infection - malaria.
| Features of malaria include abdominal pain, diarrhoea, headache and flu-like symptoms.
158
What are Heinz bodies on blood films associated with?
Glucose-6-dehydrogenase deficiency - G6PD, Heinz bodies are denatured haemoglobin aggregates the are found in the cytoplasm of red blood cells. Recessive carriers of the G6PD mutation are protected against malaria.
159
What are Reed-Sternberg cells associated with?
Hodgkin's lymphoma - classically they present with asymmetrical painless lymphadenopathy
160
What are the causes of red urine? (5)
1. Blood
2. Porphyrinuria
3. Methamoglobinaemia
4. Food ingestion (beetroots and blackberries)
5. Drug ingestion
161
Which anti-tuberculous drug causes red urine?
Rifampicin
162
What is stress haematuria?
It is AKA 'march haematuria' or 'exercise-induced haematuria', and occurs after vigorous forms of exercise. It is painless and of short duration.
163
A 16 year old girl who has recently started on the COCP presents a week later with abdominal pain, vomiting and blood in her urine. What is the most likely differential?
Porphyria - acute intermittent porphyria (attacks can also be induced by alcohol). The clinical features are caused by the accumulation of porphyrins (haemoglobin precursors).
