W07 - PAEDS: Allergies (Paeds); Paed Nephrology; Paed Sx; Paed Urology Flashcards
Describe the pathophysiological mechanisms of IgE mediated allergy
Histamine , Tryptase, Hydrolase
Later biphasic reaction: Secreted inflammatory mediators – Prostaglandins, Leukotrienes, PAF, Cytokines
HISTAMINE:
Bronchial smooth muscle contraction
Vasodilation
Separation of endothelial cells (responsible for hives)
Pain and itching
TRIGGERS:
Food
Environmental Allergen
Drug
Sting / Bite
Idiopathic
Recognise the presenting features suggestive of IgE medicated food allergy and be able to elicit an allergy focussed history
Mild/moderate
Severe: +airway, bronchispasm, hypoT
Formulate and justify a diagnosis of IgE Mediated allergy
- previous reactions
- atopy
- FHx
- Response to Tx
- Co-existing asthma? - bronchospasm exacerbation
Be able to identify and select appropriate investigations to aid diagnosis of suspected food allergy
SKIN PRICK TESTING
- strong negative predictor
SPECIFIC IgE
- no risk of reaction,
- unreliable in eczema
- delay
ORAL FOOD CHALLENGE
GOLD STANDARD
daycase procedure, double blind controlled.
Identify and describe the management for the prevention and treatment of food allergy
Avoidance of triggers
H1- Antihistamine (2nd or 3rd generation)
- PYRITON
- CHLORPHENAMINE
(1st gen sedating)
(2nd or 3rd are non-sedating)
High Dose Antihistamines +/- second antihistamine
Leukotriene Antagonist
Corticosteroids (3-5 days)
Tranexamic Acid
Anti IgE Monoclonal antibody (Omalizumab) in children over 7 years of age
Hereditary angioedema
C4 and C1 Esterase Inhibitor Dysfunction
Signs of anaphylaxis
Laryngeal Oedema
Hypotension/collapse
Bronchospasm
Feeling of impending doom
Onset usually in minutes
- onset around 60mins, faster = worse prognosis
- 20% have biphasic reaction 1-8 hrs later therefore need steroids and hospital admission
RF for anaphylaxis
Asthma (poorly controlled)
Stress
Exercise
Viral infection
Alcohol
Mgmt for Anaphylaxis
EPIPEN
Adult 0.3mg / 0.5mg, Junior 0.15mg
Education on use home/school
1st line treatment of anaphylaxis
Early use is associated with better outcomes
Potential interaction with B-blockers and tricyclics
ACTIONS:
Reverses peripheral vasodilation
Increases peripheral vascular resistance
Improves BP and coronary perfusion
Decreases angiooedema
Causes bronchodilation
Decreases release of inflammatory mediators
- hx of severe reaction, trace amounts
- cvd, resp, co-existing asthma comorbidities
Food Allergies
RF: existing allergies, atopy
Peanut:
> avoid
> immuno rx?, Palforzia
Egg:
67% grow out of it by 5yo
> promote re-introduction, egg ladder
Milk:
D&V, confusion, infants = histamine
D&V, eczema, bloating bleeding, irritability = non-histamine, non-IgE MOST COMMON
Fruit & Veg Allergy
Oral Allergy Syndrome
Cross reactivity of tree/plant pollens and foods
Causes mainly oral symptoms - itching, mouth swelling, tongue discomfort etc…
Birch - kiwi, apple, pear, nectarines
Alder - celery, pear, apple, cherry
Ragweed - watermelon, banana, cucumber
NEPHROTIC SYNDROME in paeds
*proteinuria, intravascular depletion,
* glomerular disease
* Interaction between lymphocytes (T and B cells) and podocytes
- hypoalbuminemia = oedema
- frothy urine
- minimal change most prevalent
- followed by Focal segmental glomerulosclerosis (FSGS)
> PREDNISOLONE
!cushings
Investigating glomerular disease
i. DIPSTIC
ii. PROTEIN:CREATININE
iii. 24hr urine (gold standard)
NEPHRITIC SYNDROME in paeds
- haematuria, intravascular overload
- glomerular disease
- fluid overload, JVP, oedema
- increased creatinine
- hyponatremia, hyperk.
Acquired Glomreulopathy in paeds
PODOCYTE implicated in Minimal Change Disease
BASEMENT MEMBRANE implicated in Post Infectious Glomerulonephritis
ENDOTHELIAL CELL implicated in PIGN, Haemolkytic Uremic Syndrome
MESANGIAL CELL implicated in
IgA Vasculitis
* common in children
+STEROID RESISTANT NEPHROTIC SYNDROME: genetic factor, podocyte loss, progressive inflammation and sclerosis
Congenital Glomerulopathy
*rare, layer involved
PODOCYTE DYSFUNCTION
BASEMENT MEMBRANE PROTEIN DYSFUNCTION
ENDOTHELIAL VASCULAR DYSFUNCTION
Considerations for steroid therapy in paeds
Behaviour
Mood lability
Sleep disturbance
*infection risk: varicella status, pneumococcal vax, abx prophylaxis
Acute post-infectious glomerulonephritis
Group Strep A, beta hemolytic
throat, skin
- ag mimicry produces Ab-Ag complexes = TYPE 3 HYPERSENSITIVITY
= AKI
*self-limiting
* bacterial culture!
> Abx
Support renal functions
Diuretics
IgA Nephropathy
Most common glomerulonephritis
1-2 days after URTI
Usually older children and adults
Recurrent macroscopic haematuria
Chronic microscopic haematuria
Varying degree of proteinuria
- biopsy confirms: IgA, IgG, C3 deposits
> ACEi - mild disease, proteinuria
imm suppr.
Mesangial Deposits of IgA, IgG, and C3 on immunostaining are suggestive of which glomerular disease?
IgA Nephropathy
HSP IgA Vasculitis
HENOCH SCHONLEIN PURPURA
* VASCULITIS (most common childhood vasculitis): palpable purpura
+ abdo pain
+ renal involvement
+ arthritis
+ BIOPSY
5-15yrs
associated with sensitivity vs nephrotic/nephritic IgAN, but still nephritic in picture
post viral trigger or drug trigger
4-6w duration
> symptomtic
glucocorticoid rx: improve GI involvement
imm suppr.
LT hypertension and proteinuria screening
PSGN Vs IgAN
Latency
Imm complexes in PSGN biopsy
* both nephritic
In addition, PSGN classically presents with hypocomplementemia, and if the patient undergoes a renal biopsy there is evidence of an immune complex-mediated process. In contrast, IgA Nephropathy shows normal serologic values (though IgA levels may be elevated in about a third of patients) and the renal biopsy will show mesangial IgA deposition.
One of the most important distinctions can be made in taking a good history: In PSGN, glomerulonephritis typically does not set in until several weeks after the initial infection. In contrast, IgA Nephropathy may present with so-called “synpharyngitic glomerulonephritis”–pharyngitis and glomerulonephritis at the same time.
AKI Hallmarks & Approach
hallmarks:
Anuria/oliguria (<0.5ml/kg/hr) - havent pissed for more than 8hrs
Hypertension with fluid overload
Rapid rise in plasma creatinine - 1.5x+ rise
injury resulting in retention and failure to filter
> MONITOR: BP, urine, wt
MAINTAIN: hydration, electrolytes, balance
MINIMISE: drugs
Pre-Renal AKI Causes
Perfusion
Intrinsic renal causes AKI
Glomerular disease
- haemolytic
- glomerulonephritis
Tubular injury
- necrosis dt hypoperfusion
- drugs
IInterstitial nephritis
- NSAID, AuImm
Post-Renal causes AKI
obstructive
HUS
1) haemolysis
- packed cell volume less than 30%
2) thrombocytopenia
* typically post-diarrhoea dt e coli toxin or shiga toxin = vascular dmg = pro-thrombotic state
bloody diarrhoea emergency in children
3) AKI
-serum creatinine raised
> early volume expansion
CKD in paeds
55% dt congenital anomalies of the kidneys and urinary tract =
- reflux nephropathy
- dysplasia
- obstructive
17% genetic, can be confounding to congenital abn
+ turner
+ trisomy21
+ prune belly syndrome
+ branchio-oto renal
CKD Stages
CKD 2 - 60-89
CKD3a - 45 - 59
CKD3b - 30 - 44
CKD 4 - 15 - 29
CKD 5 / ESRD - 0 - 15
UTI in paeds
neonates
- fever, vom, lethargy, irritability
- poor feeding
child
+abdo pain / loin pain / tenderness
+ malaise
*fever = pyelonephritis
- urine specimen
- dipstix unreliable <2yo
- microscopy = pyuria, bacturia
- culture
!risk of vescico-ureteric reflux
! in combination = risk of scarring
Stages of vescico-ureteric reflux
1-ureter only
2-ureter, pelvis, calyces
3-dilatation ureter
4-Moderate dilatation of ureter
± pelvis ±tortuous ureter, obliteration of fornices
5-gross dilatation/tortuosity,
no papillary impression in calyces
Investigating urinary scarring for paeds
USS
DMSA - isotope: scarring/function
MAG3 scan: dynamic
Mgmt of urinary tract infections in paeds
lower tract
> 3d oral abx
upper tract / pyelonephritis
> 7-10d abx
- fluids, hygiene, constipation
- manage voiding issues
CKD assessment & considerations
BP
- doppler goldtandard under 5yo
* ramipril common for CKD4 for 3-18yo
Bladder size
Metabolic Bone Disease
low activation of D3
> phosphate binders
> vitamin d suppl.
> growth hormone
Atherosclerosis RF
Anemia
WHO Pain Ladder
paracetamol
ibuprofen
weak opiod
strong opiod
mesenteric lymphadenitis
viral intestinal infection is the usual cause of mesenteric lymphadenitis, also known as mesenteric adenitis. It mainly affects children and teens
high temperature
URTI often
not “unwell”
Malrotation
Malrotation is an abnormality of the bowel, which happens while the baby is developing in the womb. Volvulus is a complication of malrotation and occurs when the bowel twists so the blood supply to that part of the bowel is cut off. This can be a life threatening problem.
*fairy liquid green vomit
> sx emergency
Intrussuscepton
the inversion of one portion of the intestine within another.
“intussusception is the most common cause of bowel obstruction in those 3 months to 6 years of age”
*bilious vomiting
bloody mucous PR, red currant jelly stool
*colic and dying spells, 4s caap refill
*USS target sign
> pneumostatic reduction
laparatomy
Umbillical hernia
- umbillical swelling
- worse w/ crying
- easily reducible
*spont. closure by 4yrs
repair w/ compl.
Abdo Wall Defects
GASTROSCHISIS
* expsure of gut, assoc. w/ atresia
> delayed closure
> total parenteral nutrition
EXOMPHALOS
umbilical defect w/ covered viscera
associated anomalies
> 1º / delayed closure
Hernias in Paeds
inguinal = lump/groin swelling that goes away, overall happy child and feeding
m>f, common in prems.
*incarcerated = bulge remains w/ relaxation: organs
<1yr = urgent, repair
1yr+ = elective repair
Hydrocele in Paeds
scrotal swelling, bluish colour, painless
*common in newborns, strain/crying/evening
> conservative until 5yrs
Cryptorchidism
testis cannot be manipulated into the bottom half of the scrotum
* true undescended
* retractile testis / ascending
> orchidopexy
Non-rectractile foreskin
reucrrent balanitis, pinhole meatus
* struggling to pass urine
* lichen sclerosus
> circumcision
Testicular Torsion
testicular pain, red scrotum,asymmetry, acute
> surgical correction
(6-8 hr to recover scrotum)
Vs
TORSION APPENDIX TESTIS: scrotum red, NO ASYMMETRY, blue spot seen, tender
> pain mgmt
UTI
must prevent renal scarring => HT = tx!
*screen all <6mos, atypical, recurrent
pyuria, systemic upset
USS, renography: MAG3 (drainage, function), DMSA (scarring), micturating cystourethrogram (MCUG)
What grade of VUR is the following on scan and what is the mgmt of VUR:
tortuous ureter with moderate dilatation
blunting of fornices but preserved papillary impressions
Grade 4 out of 5
grade 1: reflux limited to the ureter
grade 2: reflux up to the renal pelvis
grade 3: mild dilatation of ureter and pelvicalyceal system
5 = severe dilation, loss of fornices and papillary impressions
> conservative
abx prophylaxis until toilet trained
- TRIMETHOPRIM
STING: injection = reduction of ureteric orifice size
ureteric reimplantation
Hypospadias
MEatus on the ventral aspect of the penis
- anterior
- middle
-posterior
- US, karyotype
> surgical repositioning
