significant hematuria
> 50 rbc per microliter of urine
Define hematuria
at least 5 rbc per microliter of urine
When does the GFR of a child approach adult values?
at 3 yrs old
Between GFR and BUN, which value is affected by state of hydration and nitrogen balance? Which value is primarily influenced by the level of glomerular function?
GFR: affected by glomerular function
BUN: hydration and nitrogen balance
The most common cause of gross hematuria
bacterial urinary tract infection
Presentation with gross hematuria is usually within 1-2 days after the onset of an apparent viral upper respiratory tract infection and typically resolves within 5 days
immunoglobulin A (IgA) nephropathy
Chronic infection that is the most common cause of membranous nephropathy worldwide
MALARIA
Nephropathy presenting in the 2nd decade of life, commonly as nephrotic syndrome. Microscopic hematuria present, some have hypertension, sometimes associated with renal vein thrombosis. Normal C3.
Membranous nephropathy
Most common etiology of secondary membranous nephropathy
SLE or chronic infections (chronic hepB, congenital syphilis, malaria)
PSGN and MPGN both have similar clinical presentations. MPGN can present as acute nephritic syndrome (hematuria, hypertension, renal insufficiency) or nephrotic syndrome. C3 is low in both diseases. How can the two be differentiated?
PSGN usually +ASO, with hx of strep infection, C3 level low but resolves in 6-8 wks
MPGN C3 persists beyond 2 mos. In this case, renal bx is warranted for a histopathologic diagnosis
the most common small vessel vasculitis in childhood. It is characterized by a purpuric rash and commonly accompanied by arthritis and abdominal pain
Henoch-Schonlein purpura (HSP)
What is the histopathologic hallmark of crescentic GN?
crescents in glomeruli
Characterized by pulmonary hemorrhage and glomerulonephritis
usually presents as hemoptysis and acute nephritic syndrome with hematuria, proteinuria, and hypertension
Goodpasture disease
One of the most common causes of community-acquired acute kidney failure in young children, characterized by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and renal insufficiency, usually occuring after an acute gastrointestinal illness (~3wks after onset of GI illness; acute or bloody diarrhea)
Hemolytic-Uremic syndrome
What is the most common form of HUS?
HUS caused by toxin-producing Escherichia coli (shiga toxin of Shigella or verotoxin of E. coli ) that cause prodromal acute enteritis
Bilateral flank mass in a patient with oligohydramnios, pulmonary hypoplasia, and hypertension and absence of renal cysts by sonography of parents
Autosomal recessive polycystic kidney disease
What is the most common cause of persistent proteinuria in school-aged children and adolescents?
orthostatic proteinuria
Triad of clinical findings characteristic of nephrotic syndrome
hypoalbuminemia edema hyperlipidemia - nephrotic range proteinuria: >2-3 UPr:UCr - protein excretion of >40 mg/m2/24hr
What is the hallmark of idiopathic nephrotic syndrome?
Extensive effacement of podocyte foot processes
Among the idiopathic nephrotic syndromes which one usually does not present with hypertension and gross hematuria
Minimal change nephrotic syndrome
Subset of patients that relapse while on alternate day steroid therapy or within 28 days of completing a successful course of prednisone therapy
steroid dependent
Patients who respond well to steroid therapy but relapse >=4 times in 12 mos
frequent relapsed
Patients who fail to respond to steroid therapy within 8 wks of therapy
steroid resistant
What are the most common organisms causing spontaneous bacterial peritonitis in children with nephrotic syndrome?
S. pneumoniae and E. coli