peds34 Flashcards
how does hypercholesterolemia happen in NS?
reduced plasma oncotic pressure induces increased hepatic production of plasma proteins, including lipoproteins; plasma lipid clearance is reduced because decr lipoprotein lipase in adipose tissue
clinical features of NS
edema following an URI; patients are predisposed to thrombosis;
patients with NS at risk for what?
thrombosis and infection with encapsulated organisms (strep pnumona) so may present with bacterial peritonitis, pneumonia, or sepsis
what does CBC show in NS
elevated hematocrit as a resut of hemoconcentration due to decr protein; platelet count may be elevated
why would you get a metabolic acidosis in NS?
renal tubular acidiosis
NS on renal u/s
enlarged kidneys
management of NS?
IV infusions of albumin to treat edema; no salt diet; steroids (or cyclophosphamide or cyclosporine if don’t respond); if child is febrile, do blood and urine culture and IV antibiotic if needed
prognosis of NS
mortality about 5%, usually from infection or thrombosis; mortality in kids who are steroid-resistant;
ESRD in NS kids?
the majority of kids who are steroid-resis develop but the majority of kids who are steroid sens do not develop
Hemolytic uremic syndrome
acute renal failure in the presence of microangiopathic hemolytic anemia and thrombocytopenia
two diff subtiypes of HUS
shiga toxin asociated and atypical HUS
most common HUS subtype seen in kids
shiga-toxin associated
most common pathogen to cause shiga-txin HUS
e coli
how does shiga toxin cause HUS
vascular endothelial injury, leads to platelet thrombi formation and renal ischemia
clinical features of shiga toxin hus?
diarrheal prodrome (often bloody and may be severe) followed by suden onset of hemolytic anemia, thrombocytopenia and acute renal failure
management of shiga toxin HUS
mostly supportive; transfusion for severe anemia and thrombocytopenia; anitbiotics not indicated
prognosis for shiga toxin HUS
generally good but poor prognostic indicators are high WBCs and prolonged oliguria;
if patients do die from shiga HUS, what do they die of?
complications of colitis lke toxic megacolon or from CNS complications like cerebral infarction
causes of atypical HUS
drugs (OCPs, cyclosporine, tacrolmus); inherited
clinical features of atypical HUS
same as shiga HUS but no diarrhe
treatment of atypical HUS
supportive
prognosis of atypical HUS
some patients have a chronic relapsing course; all patients with atypical HUS have a higher risk of progression to ESRD than shiga HUS
alport’s syndrome
progressive nephritis secondary to defects in type 4 collagen within the glomerular basement membrane
inheritance of alport
x linked dome
other non-renal manifestations of alports
hearing loss that begins in childhood and is progressive; ocular abnormalities
management of alport
ace inhib initially; eventually renal transplant
multcystic renal dysplasia
most common cause of renal mass in the newborn; most often unilateral
autosomal recess polycystic idney disease or infantile polycystic kidney disease
uncommon; cystic kidneys with severe htn; liver involvement (cirrhosis) w portal htn can be seen
infants with ARPKD may have in utero hx of
oligo hydramnios, leading to pulm hypoplasia
prognosis of ARPKD
progressive and ultimately all patients require renal transplant
Aut dom PKF or adult polycystic disease
common; presents in adulthood
prognosis for ADPKD
sever htn and renal insuff; require transplant
medullary sponge kidney
occurs sporadically or may have aut dom inheritance; patient maybe symp or asymptomatic
nephronophthisis-medullary cystic disease complex
juvenile form is aut recessive and leads to ESRD in childhood
malig htn
htn associated with evidence of end organ damage
essential htn
htn without a clear etiology
most htn in kids is secondary htn or essential htn?
secondary
most common causes of htn in neonates
renal artery embolus after umbilical artery catheter placement; coarctation of the aorta; congenital renal disease, renal artery stenosis
most common causes of htn in ages 1-12 yrs
renal disease and coarctation of aorta
most common cause of htn in adolescents
renal disease and essential htn
what fundoscopic findings indicate htn?
retinal hemorrhages, papilledema, arterial-venous nicking
how to identify renal artery stenosis
radioisotope renal scan w administration of captopril or renal angiography
captopril
ACE-inhib
renal tubular acidosis
inability of the kidney to maintain normal acid/base balance because of defects in biacrb conservation or bc of defects in excretion of H ions
younger kids RTA presentation
growth failure and vomitting, and sometimes w life threatening metabolic acidosis
older kids RTA
recurrent calculi, muscle weakness, bone pain, and myalgias
how can you get polyuria in RTA
some forms of RTA lead to nephrocalcinosis which gives you urinary concentrating defects
electrolyte presentation in RTA
hyperchloremic metabolic acidosis with a normal serum anion gap
calculate anion gap
Na+ K+- Cl
when is a pos URINE anion gap seen?
distal RTA
distal RTA (type 1)
inability of distal renal tubules to excrete H+
proximal RTA (type 2)
impaired bicarb reabsoprtion y the proximal renal tubules
RTA type 3
variant of type 1, complicated by proximal tubular bicarb wasting during infancy
type 4 RTA
transient acidosis in infants and kids; hyperkalemia is the hall mark
treatment for RTA
type 1- small doses of oral alkali; types 2 and 3- large doses of oral alkali
treamtnet for type 4 RTA
furosemid to lower serum potassium, oral alkali
diffuse tubular disorder
manifested by hypokalemia, hypophosphatemia, and aminoacidduria, think Fanconi syndrome
oliguria
less than 1 mL/kg/hr
renal osteodystrophy
bone disease secondary to renal failure
nutritional management in chronic kidney disease
avoid high phosphorous, high sodium, and high potassium foods; patients need oral phosphate binder and vit D analogs to prevent renal osteodystrophy
when is dialysis or transplant indicated?
when GFR is 5-10% of normal
preferred dialysis in kids
peritoneal dialysis; but kidney transplant is the preferred treatment in kids with esrd
most common cause of transplant loss
acute and chronic rejection, noncompliance with meds, technical problems during surgery, and recurrent disease
causes of bladder outlet obstruction?
posterior urethral valves (in males), polyps, or prune belly syndrome
prune belly syndrome
absence of rectus muscles, bladder outlet obstruction, and, in males, cryptochoridsm
most common abdominal mass in newborns
multicystic dysplastic kidney, which is usually associated with atretic ureter
vesicoureteral refleux
urine refluxing from the urinary bladder into the ureters and the renal collecting system
VUR is most commonly associated with what condition?
UTIs
VUR genetics?
aut dom inheritance with varibale expression
grades of VUR
grade 1- reflux into distal ureter; grade 2- into renal pelvis and calyces w/o dilation; grade 3 is into calyces w dilateion; grade 4 clubbed calyces; grae 5 gross dilation of entire system
diagnosis of VUR
voiding cystourethrogram, in which contrast is introduced into the urinary bladder and bladder and kidneys are imaged during voiding
management of VUR
low dose prophylactic antibiotics until kid outgrows the VUR; kids with grade 4 or 5 reflux should be referred to urologist
urolithiasis
uncommon in kids; but most common stones seen in childhood are calcium, uirc acid, cystein, and mag ammonium phosphate (struvite)
what conditions are associated with renal stones
hypercaliuria, hyperoxaluria, distal RTA, hyperuricosuria, cystinuria, UTI, hyperPTH
what can cause hyperoxaluria
can be inherited or secondary to enteric malabsorption (inflamm bowel disease)
how can hyperuriosuria occur?
during the treatment of leukemia or lymphoma, with Lesch-nyhan syndrome, or primary gout
lesch-nyhan syndrome
def in an enzyme that affects how your body breaks down purines
UTIs and gender
more common in boys until 6 months of age, then more common in girls
circumcison and UTIs
before 6 months, UTIs are 10x more common in uncircumcised boys than those who are circumcised
proteus causign URI
associated w high urinary pH
urinalysis findings suggestive of UTI
leukocytes (>5-10 WBC/hpf) and a pos nitirite or leukocyte esterase on dipstick
who should have an imaging eval with UTI? (renal u/s and voiding cystourethrogram)
pyelonephriitis, recurrent UTI, all males, all girls less than 4 with cystitis,
management for uti
empiric antibiotic therapy; neonatesadmitted to hospital for IV managemen; neonates alaso get low-dose prophylactic antibitoics for at least 3 months
duration of treatment of UTI
10 daysl but 14 days for pyelonephritis
renal vein thrombosis
unilateral flank mass
central vs peripheral hypotonia
central is UMN; peripheral is LMN
associated with peripheral hypotonia
decreased fetal movements and breech presentation
associated with central hypotonia
seizures in the neonatal period
consciousness in central vs peripheral hypotonia
central has an altered level of consciousness and incr DTRs, often w ankle clonus; perip- consciousness not affected but decr DTRs and muscle bulk
causes of hypotonia
systemic pathology (sepsis, etc.) or neural pathology
what imaging do you do when you suspect central hypotonia?
head CT
spinal muscular atrophy
anterior horn cell degeneration and infiltration of microglia and astrocytes; presents with hypotonia, weakness, and tongue fasciculations
second most common hereditary neuromuscular disorder
SMA
most common inherited neuromusc disorder
duchenne muscular dystrophy
types of spinal muscular atrophy
type 1 is infantile form with onset less than 6 mos; type 2 or intermediate form is onset 6-12 mos; type 3 or juvnile form with onset greater than 3 years
inheritance of spinal muscular atrophy
aut recessive
genetics of SMA
aut recessive, all three types caused by mutation in survival motor neuron gene (SMN1) on chrom 5
clinical features of SMA
weak cry, tongue fasciculations, and difficulty sucking and swallowing; bell shaped chest; frog leg poster; normal extraocular movements and norman sensory exam
what does muscle biopsy of kid with SMA show?
atrophy of muscle fibers that were innervated by the damaged azons
management of SMA
supportive
