Pathology Part 1 Flashcards
Achondroplasia
An autosomal dominant disorder associated with short stature. It is caused by a mutation in the fibroblast growth factor receptor 3 (FGFR-3) gene.
Features of Achondroplasia
> Short limbs with shortened fingers > Large head with frontal bossing > Narrow foramen magnum > Midface hypoplasia with a flattened nasal bridge > 'Trident' hands > Lumbar lordosis
Rhizomelia
Short limbs
Brachydactyly
Shortened fingers
Risk factors for Achondroplasia
Advancing parental age at the time of conception
Treatment for Achondroplasia
No specific therapy
Some individuals benefit from limb lengthening procedures - involves application of Ilizarov frames and targeted bone fractures
Acute epiglottitis
Acute epiglottitis is rare but serious infection characterized by swelling and inflammation of the epiglottis.
What is the main cause of Acute epiglottitis?
Haemophilus influenzae type B
What vaccine has a caused a decrease in Acute epiglottitis?
Haemophilus influenzae type B vaccine (HiB vaccine)
Features of Acute epiglottitis
- rapid onset
- high temperature, generally unwell
- stridor
- drooling of saliva
- ‘tripod’ position: the patient finds it easier to breathe if they are leaning forward and extending their neck in a seated position
Stridor
A high-pitched sound that is heard best with inspiration. Caused by an obstruction or narrowing in upper airway.
Diagnosis of Acute epiglottitis
Direct visualization (only by senior/airway trained staff)
Why is acute epiglottitis only examined by senior/airway trained staff?
Due to the risk of acute airway obstruction
Treatment of Acute epiglottitis
- Immediate senior involvement
- endotracheal intubation to protect the airway
- Oxygen therapy
- Intravenous antibiotics
Acute lymphoblastic leukaemia
The most common malignancy affecting children and accounts for 80% of childhood leukaemias.
Features of Acute lymphoblastic leukaemia
Features of bone marrow failure:
- anaemia: lethargy and pallor
- neutropaenia: frequent or severe infections
- thrombocytopenia: easy bruising, petechiae
Additional features of Acute lymphoblastic leukaemia besides bone marrow failure
> bone pain > splenomegaly > hepatomegaly > fever is present in up to 50% of new cases > testicular swelling
Why is fever a presenting feature in up to 50% of new cases of Acute lymphoblastic leukaemia?
Represents infection or constitutional symptom
Poor prognostic factors for Acute lymphoblastic leukaemia
- age < 2 years or > 10 years
- WBC > 20 * 109/l at diagnosis
- T or B cell surface markers
- non-Caucasian
- male sex
What age does testicular torsion usually occur?
Most common around puberty
What age does irreducible inguinal hernia usually occur?
Most common in children < 2 years old
What age does epididymitis usually occur?
Rare in prepubescent children
Alpha-thalassaemia
Inherited condition which causes a deficiency of alpha chains in haemoglobin
What is the sex determining gene present on the Y chromosome?
SRY gene - which causes differentiation of the gonad into a testis
What happens if the SRY gene is absent on the Y chromosome?
If absent (i.e. in a female) then the gonads differentiate to become ovaries
What is the most common cause of Ambiguous genitalia in newborns?
Congenital adrenal hyperplasia
Apgar score
Used to assess the health of a newborn baby
What are the categories present in the APGAR score?
Pulse Respiratory effect Colour Muscle tone Reflex irritability
Acute appendicitis features
- Central abdominal pain - radiates to the right iliac fossa
- Low-grade pyrexia
- Minimal vomiting
What age group is acute appendicitis uncommon?
Under 4 years old but in this group often presents with perforation
Features of severe asthma attack in children
> SpO2 < 92% > PEF 33-50% best or predicted > Too breathless to talk or feed > HR over 125 (>5 years) > HR over 140 (1-5 years) > RR over 30 breaths/min (>5 years) > RR over 40 (1-5 years) > Use of accessory neck muscles
Features of Life-threatening asthma attack in children
> SpO2 <92% > PEF <33% best or predicted > Silent chest > Poor respiratory effort > Agitation > Altered consciousness > Cyanosis
Features of Moderate asthma attack in children
> SpO2 > 92%
No clinical features of severe asthma
PEF > 50% best or predicted in children >5 years old
Management of severe/life-threatening asthma attack in children
Transferred immediately to hospital.
Management of mild/moderate asthma attacks in children
- Give a beta-2 agonist via a spacer (for a child < 3 years use a close-fitting mask)
- Give 1 puff every 30-60 seconds up to a maximum of 10 puffs
- If symptoms are not controlled repeat beta-2 agonist and refer to hospital
- Steroid therapy should be given to all children with an asthma exacerbation - should be given for 3-5 days
Asthma management of children 5 to 16 years old
- Short-acting beta agonist (SABA)
- SABA + paediatric low-dose ICS
- SABA + paediatric low-dose ICS + (LTRA)
- SABA + paediatric low-dose ICS + (LABA)
- SABA + switch ICS/LABA to a MART, that includes a paediatric low-dose ICS
- SABA + paediatric moderate-dose ICS + MART
Asthma management of children under 5 years old
- Short-acting beta agonist (SABA)
- SABA + an 8-week trial of paediatric MODERATE- (ICS)
- SABA + paediatric low-dose ICS + (LTRA)
- Stop the LTRA and refer to asthma specialist
What should be done after a child under 5 years old has been given a SABA + an 8-week trial of paediatric MODERATE-dose inhaled corticosteroid (ICS) for asthma management?
After 8-weeks stop the ICS and monitor the child’s symptoms:
if symptoms did not resolve during the trial period, review whether an alternative diagnosis is likely
if symptoms resolved then reoccurred within 4 weeks of stopping ICS treatment, restart the ICS at a paediatric low dose as first-line maintenance therapy
if symptoms resolved but reoccurred beyond 4 weeks after stopping ICS treatment, repeat the 8‑week trial of a paediatric moderate dose of ICS
Maintenance and reliever therapy (MART)
A form of combined ICS and LABA treatment in which a single inhaler, containing both ICS and a fast-acting LABA, is used for both daily maintenance therapy and the relief of symptoms as required
What is a low dose paediatric ICS?
<= 200 micrograms budesonide or equivalent = paediatric low dose
What is a paediatric moderate dose ICS?
200 micrograms - 400 micrograms budesonide or equivalent = paediatric moderate dose
What is a paediatric high dose ICS?
> 400 micrograms budesonide or equivalent= paediatric high dose.
ADHD
DSM-V defines ADHD as a condition incorporating features relating to inattention and/or hyperactivity/impulsivity that are persistent. Like many paediatric conditions, there has to be an element of developmental delay.
Diagnosis of ADHD by DSM-V criteria
For children up to the age of 16 years, six of these features have to be present; in those aged 17 or over, the threshold is five features.
What are the symptoms of Inattention in ADHD?
Does not follow through on instructions
Reluctant to engage in mentally-intense tasks
Easily distracted
Finds it difficult to sustain tasks
Finds it difficult to organise tasks or activities
Often forgetful in daily activities
Often loses things necessary for tasks or activities
Often does not seem to listen when spoken to directly
What are the symptoms of Hyperactivity/Impulsivity in ADHD?
Unable to play quietly
Talks excessively
Does not wait their turn easily
Will spontaneously leave seat when expected to sit
Is often ‘on the go’
Often interruptive or intrusive to others
Will answer before a question has been finished
WIll run & climb where not appropriate
When is drug therapy given in ADHD?
As a last resort and is only available to those aged 5 years or more.
Methylphenidate
Drug used in ADHD - A CNS stimulant which primarily acts as a dopamine/norepinephrine reuptake inhibitor.
Methylphenidate side effects
Abdominal pain, nausea and dyspepsia.
In children, weight and height should be monitored every 6 months
Drugs available for management of ADHD
Methylphenidate
Lisdexamfetamine
Dexamfetamine
What should be done before giving drug therapy in ADHD?
All of these drugs are potentially cardiotoxic.
Perform a baseline ECG before starting treatment, and refer to a cardiologist if there is any significant past medical history or family history, or any doubt or ambiguity.
Autism spectrum disorder (ASD)
A neurodevelopmental condition characterized by qualitative impairment in social interaction and communication as well as repetitive stereotyped behaviour, interests, and activities. Symptoms are usually present during early childhood, but may be manifested later.
Pharmacological interventions for Autism spectrum disorder
SSRIs: helpful to reduce symptoms like repetitive stereotyped behaviour, anxiety, and aggression
Antipsychotic drugs: useful to reduce symptoms like aggression, self-injury.
Methylphenidate: for attention deficit hyperactivity disorder (ADHD).
Biliary atresia
Involves either obliteration or discontinuity within the extrahepatic biliary system, which results in an obstruction in the flow of bile.
This results in a neonatal presentation of cholestasis in the first few weeks of life.
The three types of Biliary atresia
Type 1
Type 2
Type 3
Type 1 Biliary atresia
The proximal ducts are patent, however, the common duct is obliterated
Type 2 Biliary atresia
There is atresia of the cystic duct and cystic structures are found in the porta hepatis
Type 3 Biliary atresia
There is atresia of the left and right ducts to the level of the porta hepatis, this occurs in >90% of cases of biliary atresia
Symptoms of Biliary atresia
Patients typically present in the first few weeks of life with:
> Jaundice extending beyond the physiological two weeks
> Dark urine and pale stools
> Appetite and growth disturbance, however, may be normal in some cases
Complications of Biliary atresia
Unsuccessful anastomosis formation
Progressive liver disease
Cirrhosis with eventual hepatocellular carcinoma
Definitive management of Biliary atresia
Surgical intervention is the only definitive treatment
Investigations for Biliary atresia
Serum bilirubin Liver function tests (LFTs) Serum alpha 1-antitrypsin Sweat chloride test Ultrasound of the biliary tree and liver Percutaneous liver biopsy with intraoperative cholangioscopy
Diagnostic markers for Biliary atresia
Total bilirubin may be normal, whereas conjugated bilirubin is abnormally high
Serum bile acids and aminotransferases are usually raised
Ultrasound of the biliary tree and liver: May show distension and tract abnormalities
Bronchiolitis
A condition characterised by acute bronchiolar inflammation. Respiratory syncytial virus (RSV) is the pathogen in 75-80% of cases.
Causative agent for Bronchiolitis
Respiratory syncytial virus (RSV)
Epidemiology of Bronchiolitis
> Most common cause of a serious LRT infection in < 1yr olds.
> Maternal IgG provides protection to newborns against RSV
> Higher incidence in winter
Symptoms of Bronchiolitis
> coryzal symptoms precede:
dry cough
increasing breathlessness
wheezing, fine inspiratory crackles (not always present)
feeding difficulties associated with increasing dyspnoea are often the reason for hospital admission
Symptoms requiring immediate referral to hospital (emergency).
- apnoea (observed or reported)
- child looks seriously unwell to a professional
- severe respiratory distress, for example grunting, marked chest recession, or a respiratory rate of over 70 breaths/minute
- central cyanosis
- persistent oxygen saturation of less than 92%
Investigation for Bronchiolitis
immunofluorescence of nasopharyngeal secretions may show RSV
Management of Bronchiolitis
- Humidified oxygen if the oxygen saturations are persistently < 92%
- Nasogastric feeding if children cannot take enough fluid/feed by mouth
Caput succedaneum
Describes oedema of the scalp at the presenting part of the head, typically the vertex.
This may be due to mechanical trauma of the initial portion of the scalp pushing through the cervix in a prolonged delivery or secondary to the use of ventouse (vacuum) delivery
Caput succedaneum features
> Soft, puffy swelling due to localised oedema
crosses suture lines
Resolves within days
Present at birth
Cephalohaematoma
Seen as a swelling on the newborns head. It typically develops several hours after delivery and is due to bleeding between the periosteum and skull.
How long does it take for a Cephalohaematoma to resolve?
Up to 3 months
Most common site for Cephalohaematoma
Parietal region
Difference in presentation of Cephalohaematoma and Caput succedaneum
Caput succedaneum - present at birth
Cephalohaematoma - develops 2-3 hours after birth
Features of Cephalohaematoma
> Does not cross suture lines
Takes months to resolve
Develops several hours after birth
Cerebral palsy
May be defined as a disorder of movement and posture due to a non-progressive lesion of the motor pathways in the developing brain.
Causes of Cerebral palsy
Antenatal (80%): e.g. cerebral malformation and congenital infection (rubella, toxoplasmosis, CMV)
Intrapartum (10%): birth asphyxia/trauma
Postnatal (10%): intraventricular haemorrhage, meningitis, head-trauma
Cerebral palsy features
- abnormal tone early infancy
- delayed motor milestones
- abnormal gait
- feeding difficulties
- learning difficulties (60%)
- epilepsy (30%)
- squints (30%)
- hearing impairment (20%)
Chickenpox and Shingles
Chickenpox is caused by primary infection with varicella zoster virus.
Shingles is a reactivation of the dormant virus in dorsal root ganglion
Common complications of chickenpox
Secondary bacterial infection of the lesions
Whilst this commonly may manifest as a single infected lesion/small area of cellulitis, in a small number of patients invasive group A streptococcal soft tissue infections may occur resulting in necrotizing fasciitis
Complications (rare) for chickenpox
pneumonia
encephalitis
disseminated haemorrhagic chickenpox
arthritis, nephritis and pancreatitis
Chickenpox route of transmission
Spread via the respiratory route
Can be caught from someone with shingles
incubation period = 10-21 days
Infectivity period for Chicken pox
= 4 days before rash, until 5 days after the rash first appeared*
Features of chickenpox
- fever initially
- itchy, rash starting on head/trunk before spreading.
- Initially macular then papular then vesicular
- systemic upset is usually mild
Mumps
Fever, malaise, muscular pain
Parotitis (‘earache’, ‘pain on eating’): unilateral initially then becomes bilateral in 70%
Parotitis
Inflammation of parotid glands - earache and ‘pain on eating’
Rubella
Rash: pink maculopapular, initially on face before spreading to whole body,
usually fades by the 3-5 day
Lymphadenopathy: suboccipital and postauricular
Erythema infectiosum
Also known as fifth disease or ‘slapped-cheek syndrome’
Caused by parvovirus B19
Lethargy, fever, headache
‘Slapped-cheek’ rash spreading to proximal arms and extensor surfaces
Hand, foot and mouth disease
Caused by the coxsackie A16 virus
Mild systemic upset: sore throat, fever
Vesicles in the mouth and on the palms and soles of the feet
Patau syndrome (trisomy 13)
Microcephalic, small eyes
Cleft lip/palate
Polydactyly
Scalp lesions
Edward’s syndrome (trisomy 18)
Micrognathia
Low-set ears
Rocker bottom feet
Overlapping of fingers
Micrognathia
A term for a lower jaw that is smaller than normal.
Microcephalic
A condition where a baby’s head is much smaller than expected.
Macrocephaly
The measurement around the widest part of the head) that is greater than the 98th percentile on the growth chart.
Pierre-Robin syndrome
Micrognathia
Posterior displacement of the tongue (may result in upper airway obstruction)
Cleft palate
Prader-Willi syndrome
Hypotonia
Hypogonadism
Obesity
William’s syndrome
Short stature Learning difficulties Friendly, extrovert personality Transient neonatal hypercalcaemia Supravalvular aortic stenosis
Cause of Cleft Lip
Results from failure of the fronto-nasal and maxillary processes to fuse
Cause of Cleft palate
Results from failure of the palatine processes and the nasal septum to fuse
Most common congenital deformity affecting the orofacial structures
Cleft lip and palate
Management of cleft lip and palate
Cleft lip is repaired earlier than cleft palate
Cleft palates are typically repaired between 6-12 months of age
Coeliac disease
Caused by sensitivity to the protein gluten. Repeated exposure leads to villous atrophy which in turn causes malabsorption. Children normally present before the age of 3 years, following the introduction of cereals into the diet
Coeliac disease
Caused by sensitivity to the protein gluten. Repeated exposure leads to villous atrophy which in turn causes malabsorption. Children normally present before the age of 3 years, following the introduction of cereals into the diet
Coeliac disease
Caused by sensitivity to the protein gluten. Repeated exposure leads to villous atrophy which in turn causes malabsorption.
Features of Coeliac disease in children
> failure to thrive
diarrhoea
abdominal distension
older children may present with anaemia
many cases are not diagnosed to adulthood
Diagnosis of Coeliac disease
Jejunal biopsy showing subtotal villous atrophy
anti-endomysial and anti-gliadin antibodies are useful screening tests
Antibodies in Coeliac disease
anti-endomysial and anti-gliadin antibodies