Approach to hematuria (pediatrics): Clinical sciences

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Introduction0:00–0:37

Hematuria is the presence of microscopic or macroscopic blood in the urine. Healthy kidneys filter blood by removing waste products while retaining important molecules and blood elements.
While kidneys that have lost their filtering ability allow red blood cells or RBC S to pass into the urine hematuria can be benign and transient.
While in other cases, kidney damage causes persistent hematuria which can be categorized as glomerular or nonglomerular in origin.

Urine Dipstick0:37–2:14

When a pediatric patient presents with hematuria, your first step is to obtain a urine dipstick to confirm the presence of blood.
Here's a clinical pearl to keep in mind at first glance, pink or red urine is suspicious for hematuria. But if a urine dipstick is negative for blood, be sure to consider other causes of discolored urine such as beet ingestion, rifAMPin use in porphyria due to oxidation of porphyrins or build up of urate crystal precipitation in newborns.
Ok. If the urine dipstick is positive for blood, obtain a focused history and physical examination and order a urinalysis with microscopy to assess the quantity of RBC S.
If microscopy reveals more than five RBC S per high power field, you can confirm an abnormal amount of blood in the urine.
Now, here's a clinical pearl. If your patient presents with discolored urine that tests positive for blood on a urine dipstick, but no RBC S are seen on urine microscopy.
Evaluate for myoglobinuria and hemoglobinuria. Myoglobinuria can be seen in conditions like rhabdomyolysis, extreme exercise or myopathies in which myoglobin is excreted in the urine due to increased skeletal muscle breakdown.
On the other hand, hemoglobinuria is caused by rapid hemolysis which results in the excretion of hemoglobin in the urine.
In this case, your patient may also be anemic or appear jaundiced. Once you confirm the presence of rbcs on urine microscopy repeat the urinalysis twice more.

Transient hematuria2:14–2:39

One week apart, if the hematuria resolves, meaning the repeat urinalysis reveals no RBC S, you can diagnose transient hematuria which could be related to conditions such as fever, exercise, trauma or a urinary tract infection.
On the flip side. If the repeat urinalysis with microscopy continues to be positive for RBC S diagnose persistent hematuria.

Persistent hematuria2:39–2:58

This is defined as more than 4 to 6 weeks of ongoing hematuria in the absence of exercise, menses or trauma. Next, assess for Nephritic syndrome.

Glomerular source2:58–3:24

Nephritic syndrome is characterized by cola or tea colored urine and a decrease in urine output. While the physical examination reveals elevated BP and edema.
Take another look at the urinalysis and microscopy and you're likely to see RBC casts and possibly proteinuria. If these findings are present diagnose nephritic syndrome, then assess for an underlying cause of glomerulonephritis begin your workup by ordering additional labs.

Workup3:24–4:37

Labs include serum creatinine complements, C three and C four antistreptolysin O or A so titer as well as serum iga and galactose deficient iga.
One additionally, don't forget to check autoantibodies. More specifically cytoplasmic anti neutrophil cytoplasmic antibody or C anca perinuclear antineutrophil cytoplasmic antibody or P anca anti glomerular basement membrane or anti GBM antibody antinuclear antibody or A N A anti double stranded DNA anti DS DNA antibody and anti Smith antibody.
You should also consider obtaining a renal biopsy and evaluating the specimen using light microscopy, immunofluorescence and electron microscopy as well as H and E and pas stains.
Your next step is to assess for a history of a recent infection. Ok.

Poststreptococcal glomerulonephritis4:37–5:38

Let's start by discussing patients who had a recent group, a streptococcal infection. This should make you consider post streptococcal glomerulonephritis.
Labs usually reveal a low C three normal C four and positive aso titer based on these findings diagnosed post streptococcal glomerulonephritis while a kidney biopsy is not generally indicated to make this diagnosis.
But if it is performed immunofluorescence will show a granular appearance from the IDG I GM and C three deposits, which is referred to as lumpy bumpy or starry sky.
Now, here's a high yield fact, although treating strep pharyngitis with penicillin can prevent strep complications such as rheumatic fever and the spread of nephritogenic streptococci.
Keep in mind that it does not prevent post streptococcal glomerulonephritis. Ok.
Now, let's say your patient has a recent viral U RI instead here, consider iga nephropathy. Labs may reveal elevated levels of galactose deficient iga one and serum iga as well as an increased IGA to C three ratio.

IgA nephropathy5:38–6:04

If the renal biopsy with immunofluorescence reveals mesangial iga immune deposits, diagnose iga nephropathy. All right, let's say your patient did not have a recent acute infection.

Alport syndrome6:04–7:05

You will then want to assess for hearing loss for patients who have sensory neural hearing loss. Consider Alport Syndrome.
Your patient might have a family history of deafness and renal failure. Lab findings are usually nonspecific.
So use a renal biopsy to confirm the diagnosis. Electron microscopy will reveal glomerular basement membrane splitting as well as thinning and thickening of the glomerular basement membrane with a basket weave appearance.
Additionally, immunofluorescence will show the absence of the type four collagen chain. With these findings, you can diagnose Alport syndrome.
Here's a clinical Pearl Output syndrome can also be diagnosed from a skin biopsy which demonstrates the absence of type four collagen or through genetic testing, which may reveal the col four A five mutation.

ANCA Associated Vasculitis7:05–8:00

Now, let's go back and discuss cases where hearing is intact, hear, assess for hemoptysis. First, let's look at patients where hemoptysis is present.
Let's say that the labs are anchor positive and the renal biopsy with light microscopy reveals segmental necrotizing glomerulonephritis and immunofluorescence shows negative or minimal immunoglobulin and complement deposition if so consider anca associated vasculitis.
Next, assess the anca staining pattern on biopsy. If the pattern is C anca positive diagnose granulomatosis with polyangiitis or GPA formerly known as Wegner granulomatosis.
On the flip side, if the biopsy is P anca positive diagnose microscopic polyangiitis or MP going back to cases of hemoptysis.

Anti-GBM disease8:00–9:43

Now, let's say that the labs are positive for anti GBM antibody. If renal biopsy with immunofluorescence reveals a linear appearance of IgG deposition along the glomerular basement membrane diagnose anti GBM disease.
All right, if your patient does not have hemoptysis, consider immune complex mediated glomerulonephritis. These patients may present with a history of a chronic infection like hepatitis B or C or a chronic condition like an autoimmune disease.
Labs might demonstrate a low C three and C four and ana anti double strand DNA and anti Smith antibodies might be positive.
You will want to assess the renal biopsy if H and E PA S and silver stains under light microscopy reveal mesangial hypercellularity and basement membrane thickening, often described as a tram tract pattern.
Diagnose membranoproliferative glomerulonephritis. On the other hand, if the biopsy under light microscopy reveals a wire loop glomerular capillary appearance, diagnose diffuse proliferative glomerulonephritis.
Now, here's a clinical pearl. Any patient with glomerulonephritis can present with or rapidly develop progressive crescentic glomerulonephritis.
On renal biopsy, you can identify this by the presence of glomerular crescent. This condition has a poor prognosis and can lead to renal failure if left untreated.

Nonglomerular source of hematuria9:43–10:09

Now, let's back up and consider cases of hematuria where there are no signs of nephritic syndrome. These cases are often due to congenital or neoplastic processes or due to hypercalciuria or kidney stone or hypoperfusion.
So, next, assess for an abdominal mass. Ok.
Starting with cases where an abdominal mass is palpated. This raises concern for a congenital or neoplastic process to obtain a renal ultrasound and assess for pain if the patient doesn't have pain, consider a Wilms tumor affected Children are typically under five years of age and the physical exam may reveal an elevated BP if the ultrasound reveals a large heterogeneous solid renal mass with smooth margins with or without vascular involvement, diagnose Wilms tumor.

Abdominal mass palpated10:09–10:20

Wilms tumor10:20–10:45

Polycystic kidney disease10:45–11:46

All right, moving on to cases where patients have abdominal or flank pain. If so, consider polycystic kidneys or hydronephrosis.
Let's start with polycystic kidney disease affected individuals might report increased thirst, frequent urination, poor feeding and poor growth and their family history might be positive for polycystic kidney disease.
Physical examination may reveal elevated BP if the ultrasound shows an enlarged kidney with cysts in the medulla and cortex, diagnose polycystic kidney disease.
Now, another clinical pearl polycystic kidney disease can be inherited in either an autosomal recessive or autosomal dominant pattern.
While the autosomal recessive pattern is known as infantile cystic renal disease and affects the liver as well as the kidneys.
The more common autosomal dominant polycystic kidney disease usually presents in adulthood. Ok.

Structural abnormalities11:46–12:09

Now, let's discuss patients with hydronephrosis due to a structural abnormality. These patients commonly present with a history of urinary tract infections.
If the ultrasound shows hydronephrosis, you can diagnose a structural abnormality of the urinary tract such as ureteropelvic junction, obstruction, and ureterovesical junction obstruction.

No abdominal mass palpated12:09–12:59

Ok. Now, let's go back to where we assessed for an abdominal mass and discuss cases where no mass is palpated.
Next, assess for pain. First, let's start with cases where there is no pain.
Here, consider hypercalciuria, which simply means there's excess calcium excreted in the urine. This can be associated with a family history of nephrolithiasis.
If the renal ultrasound reveals diffusely echogenic pyramids with or without shadowing, your next step is to order a 24 hour urine collection, then assess the calcium excretion by calculating a calcium to creatinine ratio.
If the ratio is elevated, you can diagnose hypercalciuria going back. Now, let's discuss cases of hematuria with no abdominal mass but there is associated abdominal or flank pain.

Nephrolithiasis12:59–13:43

Here, consider a kidney stone or renal hypoperfusion. Next order a renal ultrasound, starting with nephrolithiasis, affected individuals may report a reduced fluid intake while their physical examination might reveal costovertebral angle tenderness.
If the renal ultrasound shows echogenic foci with acoustic shadowing and a characteristic twinkle artifact. When assessed with Doppler flow diagnose nephrolithiasis on the flip side, your patient's pain may be due to nutcracker syndrome which occurs when the left renal vein is compressed between the aorta and the superior mesenteric artery.

Nutcracker syndrome13:43–14:27

These patients will often report that their pain radiates to the posterior medial thigh or buttock. The pain might also become worse while sitting, standing, walking or riding in a shaking vehicle.
If the ultrasound reveals a reduced caliber of the left renal vein or beak sign as it crosses between the aorta and superior mesenteric artery with dilatation of the renal vein at the renal hilum diagnosed nutcracker syndrome.

Review14:27–15:39

All right, as a quick recap. If a patient presents with hematuria, first repeat a urinalysis.
If the RBC S resolve on repeat tests, diagnose transient hematuria, which can be from various conditions like fever and exercise.
On the other hand, if the hematuria continues to be present, diagnose persistent hematuria, next, evaluate for nephritic syndrome.
If nephritic syndrome is present, consider causes like post streptococcal glomerulonephritis, iga nephropathy, Alport syndrome, GPA MPA, anti GBM disease, membranoproliferative glomerulonephritis or diffuse proliferative glomerulonephritis.
On the flip side, if there is no Nephritic syndrome, consider causes of abdominal masses like a Wilms, tumor polycystic kidney disease or urinary tract structural abnormalities or if there's no abdominal mass causes like hypercalciuria, nephrolithiasis or Nutcracker Syndrome.