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Nephrotic Syndrome

Nephrotic syndrome presents with protein in the urine. The most common story would be somebody between one and 12. So a three-year-old would be the peak age. Mom wakes up, sees the baby wake up at six in the morning with swollen shut eyes. It’s a panic call that you get, but until you see the kid on examination, around noon, the boys is found to have no periorbital edema but has 3+ pitting edema of the legs and impressive scrotal edema and ascites. So that’s, as I mentioned, dependent edema; gone down. He had had small amounts of diarrhea the previous day, but mom doesn’t know if he has had his usual amount of urine as well, because she didn’t know to look for that.

Next, on lab exam, urine shows 4+ protein. There is no blood. Then he gets blood tests and the serum albumin is 1.6. I don’t want to scare you with 0.8 or 0.6, but that you can also find. Low albumin levels, cholesterol can be as high as 500, 600. Those are the cholesterols we see with nephrotics. And the sodium is low, 127. The sodium either because it’s really low or it’s pseudohyponatremia more likely from the hyperlipidemia. So that’s not always the real sodium, but you get electrolytes because this kid with the low volume can already have some degree of renal failure.

He’s admitted to the hospital, not necessarily but in this case, to get IV albumin followed by Lasix once a day; 1 per kg of the albumin and 2 per kg of the Lasix and over the next three days the patient has a very good diuresis, pleural effusions and scrotal edema resolves and the mom is taught how to dipstick the urine and he is discharged home.

So this is a typical story of a kid with minimal change nephrotic syndrome. We don’t have to biopsy this child to know that it’s minimal change. The diagnosis is by the age, the response to treatment, and the relapse that will happen more than likely, after … we don’t know exactly when but more than likely in the next few months this kid will have a relapse. That’s minimal change. You don’t have to biopsy to make the diagnosis.

So the treatment … I think we have all realized what the definition of nephrotic syndrome with proteinuria and the hypoalbuminemia, edema and hypercholesterolemia and the causes; most commonly, minimal change. There is a minimal change that now is not completely minimal. I mean, it is still minimal but not no findings at all, but there is on immunofluorescence something that’s IgM deposits. We are not sure whether it is an entity in itself. It’s still called minimal change with IgM deposits, but it seems like these patients don’t respond as well as pure minimal change. The other causes are much less common; focal segmental glomerular sclerosis, MPGN, membranous and congenital nephrotic syndrome.

I talked about this, clinical presentation. I didn’t mention that they can have such bad edema that there can be skin breakdown with oozing of fluid, such as in the scrotal area, the vulvar area in girls, and that would require admission and IV albumin to try and mobilize the fluids a little bit, out of the interstitium back into the vascular tree. Blood pressure is normal or low. We talked about it. The diarrhea, I mentioned because they can have intestinal edema, intestinal mucosal edema.

Okay, another common complication, perhaps the most common nowadays, is thrombotic events, thrombosis. They are very hyper-coagulable, nephrotics, and they can have thrombotic emboli or just deep vein thrombosis. Any nephrotic shouldn’t have deep vein sticks or arterial sticks. They have a very high incidence of thrombotic events. The urine has massive proteinuria and we don’t have to do a 24-hour collection because we can just dipstick; 4+ equals nephrotic range proteinuria. You don’t really have to do a 24-hour collection to waste time. You start treatment, so this will be our indication of nephrotic range.

Blood tests, we already talked about. Now I talked about pseudohyponatremia but also there is hypocalcemia in the calcium that is measured, only because the albumin that the calcium is bound to is low. So there is this calculation. For every 1 gram of albumin below normal, to increase the calcium by 0.8. You know that calculation? Say an albumin is 4 and in the child it is 1.

We already talked about the complications. Infections, not only the primary peritonitis but any infection. They are much more prone to infections because they lose also other complements, IgG’s etc. Hypovolemia, thrombosis. They can have acute renal failure. It’s not common but it can happen, and when it is very long-standing and not treated they can have malnutrition.

The treatment is prednisone, that’s the drug of choice as we know; 2 per kilo per day, or 60 mg per meter square per day for six or four weeks. We’ve gone between the four and six weeks for different reasons, but four weeks would be okay. Daily, even with a good response within a week, you continue for a whole month and then every other day for another month.

There is no evidence that one way or the other is better. We teach the parents to check the urine and we have a sheet. They write down the proteinuria and the medicine dose and we get the sheet back the next time when we see them, and you see how it has responded. You don’t see the response so quickly in the urine dipsticks because they can spill 10 grams of protein a day in the beginning, that’s 4+ on the dipstick. They then go down to 2 grams for a day and it’s still 4+ on the dipstick. So they’ve improved a lot. What you see first is the diuresis really and edema going away. So that’s how they respond. Most of them will respond within two weeks, and then the rest will respond within a month. And 93% will respond.